DVT/VTE

Due to the underlying mechanism of atrial fibrillation (Afib), clots can form within the left atrial appendage. Clots that become dislodged may lead to ischemic stroke and possibly death. The 2023 guidelines for atrial fibrillation from the American College of Cardiology and American Heart Association recommend anticoagulation therapy for patients with an Afib diagnosis and a CHA₂DS₂-VASc (congestive heart failure, hypertension, age ≥ 75 years, diabetes, stroke/vascular disease, age 65 to 74 years, and female sex) score pertinent for ≥ 1 non–sex-related factor (score ≥ 2 for women; ≥ 1 for men) to prevent stroke-related complications. The CHA₂DS₂-VASc score is a 9-point scoring tool based on comorbidities and conditions that increase risk of stroke in patients with Afib. Each value correlates to an annualized stroke risk percentage that increases as the score increases.

In clinical practice, patients meeting these thresholds are indicated for anticoagulation and are considered for indefinite use unless ≥ 1 of the following conditions are present: bleeding risk outweighs the stroke prevention benefit, Afib is episodic (< 48 hours) or a nonpharmacologic intervention, such as a left atrial appendage occlusion (LAAO) device is present.¹

In patients with a diagnosed venous thromboembolism (VTE), such as deep vein thrombosis or pulmonary embolism, anticoagulation is used to treat the current thrombosis and prevent embolization that can ultimately lead to death. The 2021 guideline for VTE from the American College of Chest Physicians identifies certain risk factors that increase risk for VTE and categorizes them as transient or persistent. Transient risk factors include hospitalization > 3 days, major trauma, surgery, cast immobilization, hormone therapy, pregnancy, or prolonged travel > 8 hours. Persistent risk factors include malignancy, thrombophilia, and certain medications.

The guideline recommends therapy durations based on event frequency, the presence and classification of provoking risk factors, and bleeding risk. As the risk of recurrent thrombosis and other potential complications is greatest in the first 3 to 6 months after a diagnosed event, at least 3 months anticoagulation therapy is recommended following VTE diagnosis. At the 3-month mark, all regimens are suggested to be re-evaluated and considered for extended treatment duration if the event was unprovoked, recurrent, secondary to a persistent risk factor, or low bleed risk.²Anticoagulation is an important guideline-recommended pharmacologic intervention for various disease states, although its use is not without risks. The Institute for Safe Medication Practices has classified oral anticoagulants as high-alert medications. This designation was made because anticoagulant medications have the potential to cause harm when used or omitted in error and lead to life-threatening bleed or thrombotic complications.³Anticoagulation stewardship ensures that anticoagulation therapy is appropriately initiated, maintained, and discontinued when indicated. Because of the potential for harm, anticoagulation stewardship is an important part of Afib and VTE management. Pharmacists can help verify and evaluate anticoagulation therapies. Research suggests that pharmacist-led anticoagulation stewardship efforts may play a role in ensuring safer patient outcomes.⁴The purpose of this quality improvement (QI) study was to implement pharmacist-led anticoagulation stewardship practices at Veterans Affairs Phoenix Health Care System (VAPHCS) to identify veterans with Afib not currently on anticoagulation, as well as to identify veterans with a history of VTE events who have completed a sufficient treatment duration.

Methods

Anticoagulation stewardship efforts were implemented in 2 cohorts of patients: those with Afib who may be indicated to initiate anticoagulation, and those with a history of VTE events who may be indicated to consider anticoagulation discontinuation. Patient records were reviewed using a standardized note template, and recommendations to either initiate or discontinue anticoagulation therapy were documented. The VAPHCS Research Service reviewed this study and determined that it was not research and was exempt from institutional review board review.

Atrial Fibrillation Cohort

A population health dashboard created by the Stroke Prevention in Atrial Fibrillation/Flutter Targeting the uNTreated: a focus on health care disparities (SPAFF-TNT-D) national VA study team was used to identify veterans at VAPHCS with a diagnosis of Afib without an active VA prescription for an anticoagulant. The dashboard filtered and produced data points from the medical record that correlated to the components of the CHA₂DS₂-VASc score. All veterans identified by the dashboard with scores of 7 or 8 were included. No patients had a score of 9. Comprehensive chart reviews of available VA and non–VA-provided care records were conducted by the investigators, and a standardized note template designed by the SPAFF-TNT-D team (eAppendix 1) was used to document findings within the electronic health record (EHR). If anticoagulation was deemed to be indicated, the assigned primary care practitioner (PCP) as listed in the EHR was alerted to the note by the investigators for further evaluation and consideration of prescribing anticoagulation.

Venous Thromboembolism Cohort

VAPHCS pharmacy informatics pulled data that included veterans with documented VTE and an active VA anticoagulant prescription between November 2022 and November 2023. Veterans were reviewed in chronological order based on when the anticoagulant prescription was written. All veterans were included until an equal number of charts were reviewed in both the Afib and VTE cohorts. Comprehensive chart review of available VA- and non–VA-provided care records was conducted by the investigators, and a standardized note template as designed by the investigators (eAppendix 2) was used to document findings within the EHR. If the duration of anticoagulation therapy was deemed sufficient, the assigned anticoagulation clinical pharmacist practitioner (CPP) was alerted to the note by the investigators for further evaluation and consideration of discontinuing anticoagulation.

EHR reviews were conducted in October and November 2023 and lasted about 10 to 20 minutes per patient. To evaluate completeness and accuracy of the documented findings within the EHR, both investigators reviewed and cosigned the completed note template and verified the correct PCP was alerted to the recommendation for appropriate continuity of care. Results were reviewed in March 2024.

Outcomes

Atrial fibrillation cohort. The primary outcome was the number of veterans with Afib who were recommended to start anticoagulation therapy. Additional outcomes evaluated included the number of interventions completed, action taken by PCPs in response to the provided recommendation, and reasons provided by the investigators for not recommending initiation of anticoagulation therapy in specific veteran cases.

Venous thromboembolism cohort. The primary outcome was the number of veterans with a history of VTE events recommended to discontinue anticoagulation therapy. Additional outcomes included number of interventions completed, action taken by the anticoagulation CPP in response to the provided recommendation, and reasons provided by the investigators for not recommending discontinuation of anticoagulation therapy in specific veteran cases.

Analysis

Sample size was determined by the inclusion criteria and was not designed to attain statistical power. Data embedded in the Afib cohort standardized note template, also known as health factors, were later used for data analysis. Recommendations in the VTE cohort were manually tracked and recorded by the investigators. Results for this study were analyzed using descriptive statistics.

Results

A total of 114 veterans were reviewed and included in this study: 57 in each cohort. Seven recommendations were made regarding anticoagulation initiation for patients with Afib and 7 were made for anticoagulation discontinuation for patients with VTE (Table 1).

In the Afib cohort, 1 veteran was successfully initiated on anticoagulation therapy and 1 veteran was deemed appropriate for initiation of anticoagulation but was not reachable. Of the 5 recommendations with no action taken, 4 PCPs acknowledged the alert with no further documentation, and 1 PCP deferred the decision to cardiology with no further documentation. In the VTE cohort, 3 veterans successfully discontinued anticoagulation therapy and 2 veterans were further evaluated by the anticoagulation CPP and deemed appropriate to continue therapy based on potential for malignancy. Of the 2 recommendations with no action taken, 1 anticoagulation CPP acknowledged the alert with no further documentation and 1 anticoagulation CPP suggested further evaluation by PCP with no further documentation.

In the Afib cohort, a nonpharmacologic approach was defined as documentation of a LAAO device. An inaccurate diagnosis was defined as an Afib diagnosis being used in a previous visit, although there was no further confirmation of diagnosis via chart review. Veterans classified as already being on anticoagulation had documentation of non–VA-written anticoagulant prescriptions or receiving a supply of anticoagulants from a facility such as a nursing home. Anticoagulation was defined as unfavorable if a documented risk/benefit conversation was found via EHR review. Anticoagulation was defined as not indicated if the Afib was documented as transient, episodic, or historical (Table 2).

In the VTE cohort, no recommendations for discontinuation were made for veterans indicated to continue anticoagulation due to a concurrent Afib diagnosis. Chronic or recurrent events were defined as documentation of multiple VTE events and associated dates in the EHR. Persistent risk factors included malignancy or medications contributing to hypercoagulable states. Thrombophilia was defined as having documentation of a diagnosis in the EHR. An unprovoked event was defined as VTE without any documented transient risk factors (eg, hospitalization, trauma, surgery, cast immobilization, hormone therapy, pregnancy, or prolonged travel). Anticoagulation had already been discontinued in 1 veteran after the data were collected but before chart review occurred (Table 3).

Discussion

Pharmacy-led indication reviews resulted in appropriate recommendations for anticoagulation use in veterans with Afib and a history of VTE events. Overall, 12.3% of chart reviews in each cohort resulted in a recommendation being made, which was similar to the rate found by Koolian et al.⁵ In that study, 10% of recommendations were related to initiation or interruption of anticoagulation. This recommendation category consisted of several subcategories, including “suggesting therapeutic anticoagulation when none is currently ordered” and “suggesting anticoagulation cessation if no longer indicated,” but specific numerical prevalence was not provided.⁵

Online dashboard use allowed for greater population health management and identification of veterans with Afib who were not on active anticoagulation, providing opportunities to prevent stroke-related complications. Wang et al completed a similarly designed study that included a population health tool to identify patients with Afib who were not on anticoagulation and implemented pharmacist-led chart review and facilitation of recommendations to the responsible clinician. This study reviewed 1727 patients and recommended initiation of anticoagulation therapy for 75 (4.3%).⁶ The current study had a higher percentage of patients with recommendations for changes despite its smaller size.

Evaluating the duration of therapy for anticoagulation in veterans with a history of VTE events provided an opportunity to reduce unnecessary exposure to anticoagulation and minimize bleeding risks. Using a chart review process and standardized note template enabled the documentation of pertinent information that could be readily reviewed by the PCP. This process is a step toward ensuring VAPHCS PCPs provide guideline-recommended care and actively prevent stroke and bleeding complications. Adoption of this process into the current VAPHCS Anticoagulation Clinic workflow for review of veterans with either Afib or VTE could lead to more EHRs being reviewed and recommendations made, ultimately improving patient outcomes. 

Therapeutic interventions based on the recommendations were completed for 1 of 7 veterans (14%) and 3 of 7 veterans (43%) in the Afib and VTE cohorts, respectively. The prevalence of completed interventions in this anticoagulation stewardship study was higher than those in Wang et al, who found only 9% of their recommendations resulted in PCPs considering action related to anticoagulation, and only 4% were successfully initiated.⁶

In the Afib cohort, veterans identified by the dashboard with a CHA₂DS₂-VASc of 7 or 8 were prioritized for review. Reviewing these veterans ensured that patients with the highest stroke risk were sufficiently evaluated and started on anticoagulation as needed to reduce stroke-related complications. In contrast, because these veterans had higher CHA₂DS₂-VASc scores, they may have already been evaluated for anticoagulation in the past and had a documented rationale for not being placed on anticoagulation (LAAO device placement was the most common rationale). Focusing on veterans with a lower CHA₂DS₂-VASc score such as 1 for men or 2 for women could potentially include more opportunities for recommendations. Although stroke risk may be lower in this population compared with those with higher CHA₂DS₂-VASc scores, guideline-recommended anticoagulation use may be missed for these patients. 

In the VTE cohort, veterans with an anticoagulant prescription written 12 months before data collection were prioritized for review. Reviewing these veterans ensured that anticoagulation therapy met guideline recommendations of at least 3 months, with potential for extended duration upon further evaluation by a provider at that time. Based on collected results, most veterans were already reevaluated and had documented reasons why anticoagulation was still indicated; concurrent Afib was most common followed by chronic or recurrent VTE. Reviewing veterans with more recent prescriptions just over the recommended 3-month duration could potentially include more opportunities for recommendations to be made. It is more likely that by 3 months another PCP had not already weighed in on the duration of therapy, and the anticoagulation CPP could ensure a thorough review is conducted with guideline-based recommendations.

Most published literature on anticoagulation stewardship efforts is focused on inpatient management and policy changes, or concentrate on attributes of therapy such as appropriate dosing and drug interactions. This study highlighted that gaps in care related to anticoagulation use and discontinuation are present in the VAPHCS population and can be appropriately addressed via pharmacist-led indication reviews. Future studies designed to focus on initiating anticoagulation where appropriate, and discontinuing where a sufficient treatment period has been completed, are warranted to minimize this gap in care and allow health systems to work toward process changes to ensure safe and optimized care is provided for the patients they serve.

Limitations

In the Afib cohort, 5 of 7 recommendations (71%) had no further action taken by the PCP, which may represent a barrier to care. In contrast, 2 of 7 recommendations (29%) had no further action in the VTE cohort. It is possible that the difference can be attributed to the anticoagulation CPP receiving VTE alerts and PCPs receiving Afib alerts. The anticoagulation CPP was familiar with this QI study and may have better understood the purpose of the chart review and the need to provide a timely response. PCPs may have been less likely to take action because they were unfamiliar with the anticoagulation stewardship initiative and standardized note template or overwhelmed by too many EHR alerts.

The lack of PCP response to a virtual alert or message also was observed by Wang et al, whereas Koolian et al reported higher intervention completion rates, with verbal recommendations being made to the responsible clinicians. To further ensure these pertinent recommendations for anticoagulation initiation in veterans with Afib are properly reviewed and evaluated, future research could include intentional follow-up with the PCP regarding the alert, PCP-specific education about the anticoagulation stewardship initiative and the role of the standardized note template, and collaboration with PCPs to identify alternative ways to relay recommendations in a way that would ensure the completion of appropriate and timely review.

Conclusions

This study identified gaps in care related to anticoagulation needs in the VAPHCS veteran population. Utilizing a standardized indication review process allows pharmacists to evaluate anticoagulant use for both appropriate indication and duration of therapy. Providing recommendations via chart review notes and alerting respective PCPs and CPPs results in veterans receiving safe and optimized care regarding their anticoagulation needs.

Due to the underlying mechanism of atrial fibrillation (Afib), clots can form within the left atrial appendage. Clots that become dislodged may lead to ischemic stroke and possibly death. The 2023 guidelines for atrial fibrillation from the American College of Cardiology and American Heart Association recommend anticoagulation therapy for patients with an Afib diagnosis and a CHA₂DS₂-VASc (congestive heart failure, hypertension, age ≥ 75 years, diabetes, stroke/vascular disease, age 65 to 74 years, and female sex) score pertinent for ≥ 1 non–sex-related factor (score ≥ 2 for women; ≥ 1 for men) to prevent stroke-related complications. The CHA₂DS₂-VASc score is a 9-point scoring tool based on comorbidities and conditions that increase risk of stroke in patients with Afib. Each value correlates to an annualized stroke risk percentage that increases as the score increases.

In clinical practice, patients meeting these thresholds are indicated for anticoagulation and are considered for indefinite use unless ≥ 1 of the following conditions are present: bleeding risk outweighs the stroke prevention benefit, Afib is episodic (< 48 hours) or a nonpharmacologic intervention, such as a left atrial appendage occlusion (LAAO) device is present.¹

In patients with a diagnosed venous thromboembolism (VTE), such as deep vein thrombosis or pulmonary embolism, anticoagulation is used to treat the current thrombosis and prevent embolization that can ultimately lead to death. The 2021 guideline for VTE from the American College of Chest Physicians identifies certain risk factors that increase risk for VTE and categorizes them as transient or persistent. Transient risk factors include hospitalization > 3 days, major trauma, surgery, cast immobilization, hormone therapy, pregnancy, or prolonged travel > 8 hours. Persistent risk factors include malignancy, thrombophilia, and certain medications.

The guideline recommends therapy durations based on event frequency, the presence and classification of provoking risk factors, and bleeding risk. As the risk of recurrent thrombosis and other potential complications is greatest in the first 3 to 6 months after a diagnosed event, at least 3 months anticoagulation therapy is recommended following VTE diagnosis. At the 3-month mark, all regimens are suggested to be re-evaluated and considered for extended treatment duration if the event was unprovoked, recurrent, secondary to a persistent risk factor, or low bleed risk.²Anticoagulation is an important guideline-recommended pharmacologic intervention for various disease states, although its use is not without risks. The Institute for Safe Medication Practices has classified oral anticoagulants as high-alert medications. This designation was made because anticoagulant medications have the potential to cause harm when used or omitted in error and lead to life-threatening bleed or thrombotic complications.³Anticoagulation stewardship ensures that anticoagulation therapy is appropriately initiated, maintained, and discontinued when indicated. Because of the potential for harm, anticoagulation stewardship is an important part of Afib and VTE management. Pharmacists can help verify and evaluate anticoagulation therapies. Research suggests that pharmacist-led anticoagulation stewardship efforts may play a role in ensuring safer patient outcomes.⁴The purpose of this quality improvement (QI) study was to implement pharmacist-led anticoagulation stewardship practices at Veterans Affairs Phoenix Health Care System (VAPHCS) to identify veterans with Afib not currently on anticoagulation, as well as to identify veterans with a history of VTE events who have completed a sufficient treatment duration.

Methods

Anticoagulation stewardship efforts were implemented in 2 cohorts of patients: those with Afib who may be indicated to initiate anticoagulation, and those with a history of VTE events who may be indicated to consider anticoagulation discontinuation. Patient records were reviewed using a standardized note template, and recommendations to either initiate or discontinue anticoagulation therapy were documented. The VAPHCS Research Service reviewed this study and determined that it was not research and was exempt from institutional review board review.

Atrial Fibrillation Cohort

A population health dashboard created by the Stroke Prevention in Atrial Fibrillation/Flutter Targeting the uNTreated: a focus on health care disparities (SPAFF-TNT-D) national VA study team was used to identify veterans at VAPHCS with a diagnosis of Afib without an active VA prescription for an anticoagulant. The dashboard filtered and produced data points from the medical record that correlated to the components of the CHA₂DS₂-VASc score. All veterans identified by the dashboard with scores of 7 or 8 were included. No patients had a score of 9. Comprehensive chart reviews of available VA and non–VA-provided care records were conducted by the investigators, and a standardized note template designed by the SPAFF-TNT-D team (eAppendix 1) was used to document findings within the electronic health record (EHR). If anticoagulation was deemed to be indicated, the assigned primary care practitioner (PCP) as listed in the EHR was alerted to the note by the investigators for further evaluation and consideration of prescribing anticoagulation.

Venous Thromboembolism Cohort

VAPHCS pharmacy informatics pulled data that included veterans with documented VTE and an active VA anticoagulant prescription between November 2022 and November 2023. Veterans were reviewed in chronological order based on when the anticoagulant prescription was written. All veterans were included until an equal number of charts were reviewed in both the Afib and VTE cohorts. Comprehensive chart review of available VA- and non–VA-provided care records was conducted by the investigators, and a standardized note template as designed by the investigators (eAppendix 2) was used to document findings within the EHR. If the duration of anticoagulation therapy was deemed sufficient, the assigned anticoagulation clinical pharmacist practitioner (CPP) was alerted to the note by the investigators for further evaluation and consideration of discontinuing anticoagulation.

EHR reviews were conducted in October and November 2023 and lasted about 10 to 20 minutes per patient. To evaluate completeness and accuracy of the documented findings within the EHR, both investigators reviewed and cosigned the completed note template and verified the correct PCP was alerted to the recommendation for appropriate continuity of care. Results were reviewed in March 2024.

Outcomes

Atrial fibrillation cohort. The primary outcome was the number of veterans with Afib who were recommended to start anticoagulation therapy. Additional outcomes evaluated included the number of interventions completed, action taken by PCPs in response to the provided recommendation, and reasons provided by the investigators for not recommending initiation of anticoagulation therapy in specific veteran cases.

Venous thromboembolism cohort. The primary outcome was the number of veterans with a history of VTE events recommended to discontinue anticoagulation therapy. Additional outcomes included number of interventions completed, action taken by the anticoagulation CPP in response to the provided recommendation, and reasons provided by the investigators for not recommending discontinuation of anticoagulation therapy in specific veteran cases.

Analysis

Sample size was determined by the inclusion criteria and was not designed to attain statistical power. Data embedded in the Afib cohort standardized note template, also known as health factors, were later used for data analysis. Recommendations in the VTE cohort were manually tracked and recorded by the investigators. Results for this study were analyzed using descriptive statistics.

Results

A total of 114 veterans were reviewed and included in this study: 57 in each cohort. Seven recommendations were made regarding anticoagulation initiation for patients with Afib and 7 were made for anticoagulation discontinuation for patients with VTE (Table 1).

In the Afib cohort, 1 veteran was successfully initiated on anticoagulation therapy and 1 veteran was deemed appropriate for initiation of anticoagulation but was not reachable. Of the 5 recommendations with no action taken, 4 PCPs acknowledged the alert with no further documentation, and 1 PCP deferred the decision to cardiology with no further documentation. In the VTE cohort, 3 veterans successfully discontinued anticoagulation therapy and 2 veterans were further evaluated by the anticoagulation CPP and deemed appropriate to continue therapy based on potential for malignancy. Of the 2 recommendations with no action taken, 1 anticoagulation CPP acknowledged the alert with no further documentation and 1 anticoagulation CPP suggested further evaluation by PCP with no further documentation.

In the Afib cohort, a nonpharmacologic approach was defined as documentation of a LAAO device. An inaccurate diagnosis was defined as an Afib diagnosis being used in a previous visit, although there was no further confirmation of diagnosis via chart review. Veterans classified as already being on anticoagulation had documentation of non–VA-written anticoagulant prescriptions or receiving a supply of anticoagulants from a facility such as a nursing home. Anticoagulation was defined as unfavorable if a documented risk/benefit conversation was found via EHR review. Anticoagulation was defined as not indicated if the Afib was documented as transient, episodic, or historical (Table 2).

In the VTE cohort, no recommendations for discontinuation were made for veterans indicated to continue anticoagulation due to a concurrent Afib diagnosis. Chronic or recurrent events were defined as documentation of multiple VTE events and associated dates in the EHR. Persistent risk factors included malignancy or medications contributing to hypercoagulable states. Thrombophilia was defined as having documentation of a diagnosis in the EHR. An unprovoked event was defined as VTE without any documented transient risk factors (eg, hospitalization, trauma, surgery, cast immobilization, hormone therapy, pregnancy, or prolonged travel). Anticoagulation had already been discontinued in 1 veteran after the data were collected but before chart review occurred (Table 3).

Discussion

Pharmacy-led indication reviews resulted in appropriate recommendations for anticoagulation use in veterans with Afib and a history of VTE events. Overall, 12.3% of chart reviews in each cohort resulted in a recommendation being made, which was similar to the rate found by Koolian et al.⁵ In that study, 10% of recommendations were related to initiation or interruption of anticoagulation. This recommendation category consisted of several subcategories, including “suggesting therapeutic anticoagulation when none is currently ordered” and “suggesting anticoagulation cessation if no longer indicated,” but specific numerical prevalence was not provided.⁵

Online dashboard use allowed for greater population health management and identification of veterans with Afib who were not on active anticoagulation, providing opportunities to prevent stroke-related complications. Wang et al completed a similarly designed study that included a population health tool to identify patients with Afib who were not on anticoagulation and implemented pharmacist-led chart review and facilitation of recommendations to the responsible clinician. This study reviewed 1727 patients and recommended initiation of anticoagulation therapy for 75 (4.3%).⁶ The current study had a higher percentage of patients with recommendations for changes despite its smaller size.

Evaluating the duration of therapy for anticoagulation in veterans with a history of VTE events provided an opportunity to reduce unnecessary exposure to anticoagulation and minimize bleeding risks. Using a chart review process and standardized note template enabled the documentation of pertinent information that could be readily reviewed by the PCP. This process is a step toward ensuring VAPHCS PCPs provide guideline-recommended care and actively prevent stroke and bleeding complications. Adoption of this process into the current VAPHCS Anticoagulation Clinic workflow for review of veterans with either Afib or VTE could lead to more EHRs being reviewed and recommendations made, ultimately improving patient outcomes. 

Therapeutic interventions based on the recommendations were completed for 1 of 7 veterans (14%) and 3 of 7 veterans (43%) in the Afib and VTE cohorts, respectively. The prevalence of completed interventions in this anticoagulation stewardship study was higher than those in Wang et al, who found only 9% of their recommendations resulted in PCPs considering action related to anticoagulation, and only 4% were successfully initiated.⁶

In the Afib cohort, veterans identified by the dashboard with a CHA₂DS₂-VASc of 7 or 8 were prioritized for review. Reviewing these veterans ensured that patients with the highest stroke risk were sufficiently evaluated and started on anticoagulation as needed to reduce stroke-related complications. In contrast, because these veterans had higher CHA₂DS₂-VASc scores, they may have already been evaluated for anticoagulation in the past and had a documented rationale for not being placed on anticoagulation (LAAO device placement was the most common rationale). Focusing on veterans with a lower CHA₂DS₂-VASc score such as 1 for men or 2 for women could potentially include more opportunities for recommendations. Although stroke risk may be lower in this population compared with those with higher CHA₂DS₂-VASc scores, guideline-recommended anticoagulation use may be missed for these patients. 

In the VTE cohort, veterans with an anticoagulant prescription written 12 months before data collection were prioritized for review. Reviewing these veterans ensured that anticoagulation therapy met guideline recommendations of at least 3 months, with potential for extended duration upon further evaluation by a provider at that time. Based on collected results, most veterans were already reevaluated and had documented reasons why anticoagulation was still indicated; concurrent Afib was most common followed by chronic or recurrent VTE. Reviewing veterans with more recent prescriptions just over the recommended 3-month duration could potentially include more opportunities for recommendations to be made. It is more likely that by 3 months another PCP had not already weighed in on the duration of therapy, and the anticoagulation CPP could ensure a thorough review is conducted with guideline-based recommendations.

Most published literature on anticoagulation stewardship efforts is focused on inpatient management and policy changes, or concentrate on attributes of therapy such as appropriate dosing and drug interactions. This study highlighted that gaps in care related to anticoagulation use and discontinuation are present in the VAPHCS population and can be appropriately addressed via pharmacist-led indication reviews. Future studies designed to focus on initiating anticoagulation where appropriate, and discontinuing where a sufficient treatment period has been completed, are warranted to minimize this gap in care and allow health systems to work toward process changes to ensure safe and optimized care is provided for the patients they serve.

Limitations

In the Afib cohort, 5 of 7 recommendations (71%) had no further action taken by the PCP, which may represent a barrier to care. In contrast, 2 of 7 recommendations (29%) had no further action in the VTE cohort. It is possible that the difference can be attributed to the anticoagulation CPP receiving VTE alerts and PCPs receiving Afib alerts. The anticoagulation CPP was familiar with this QI study and may have better understood the purpose of the chart review and the need to provide a timely response. PCPs may have been less likely to take action because they were unfamiliar with the anticoagulation stewardship initiative and standardized note template or overwhelmed by too many EHR alerts.

The lack of PCP response to a virtual alert or message also was observed by Wang et al, whereas Koolian et al reported higher intervention completion rates, with verbal recommendations being made to the responsible clinicians. To further ensure these pertinent recommendations for anticoagulation initiation in veterans with Afib are properly reviewed and evaluated, future research could include intentional follow-up with the PCP regarding the alert, PCP-specific education about the anticoagulation stewardship initiative and the role of the standardized note template, and collaboration with PCPs to identify alternative ways to relay recommendations in a way that would ensure the completion of appropriate and timely review.

Conclusions

This study identified gaps in care related to anticoagulation needs in the VAPHCS veteran population. Utilizing a standardized indication review process allows pharmacists to evaluate anticoagulant use for both appropriate indication and duration of therapy. Providing recommendations via chart review notes and alerting respective PCPs and CPPs results in veterans receiving safe and optimized care regarding their anticoagulation needs.

Due to the underlying mechanism of atrial fibrillation (Afib), clots can form within the left atrial appendage. Clots that become dislodged may lead to ischemic stroke and possibly death. The 2023 guidelines for atrial fibrillation from the American College of Cardiology and American Heart Association recommend anticoagulation therapy for patients with an Afib diagnosis and a CHA₂DS₂-VASc (congestive heart failure, hypertension, age ≥ 75 years, diabetes, stroke/vascular disease, age 65 to 74 years, and female sex) score pertinent for ≥ 1 non–sex-related factor (score ≥ 2 for women; ≥ 1 for men) to prevent stroke-related complications. The CHA₂DS₂-VASc score is a 9-point scoring tool based on comorbidities and conditions that increase risk of stroke in patients with Afib. Each value correlates to an annualized stroke risk percentage that increases as the score increases.

In clinical practice, patients meeting these thresholds are indicated for anticoagulation and are considered for indefinite use unless ≥ 1 of the following conditions are present: bleeding risk outweighs the stroke prevention benefit, Afib is episodic (< 48 hours) or a nonpharmacologic intervention, such as a left atrial appendage occlusion (LAAO) device is present.¹

In patients with a diagnosed venous thromboembolism (VTE), such as deep vein thrombosis or pulmonary embolism, anticoagulation is used to treat the current thrombosis and prevent embolization that can ultimately lead to death. The 2021 guideline for VTE from the American College of Chest Physicians identifies certain risk factors that increase risk for VTE and categorizes them as transient or persistent. Transient risk factors include hospitalization > 3 days, major trauma, surgery, cast immobilization, hormone therapy, pregnancy, or prolonged travel > 8 hours. Persistent risk factors include malignancy, thrombophilia, and certain medications.

The guideline recommends therapy durations based on event frequency, the presence and classification of provoking risk factors, and bleeding risk. As the risk of recurrent thrombosis and other potential complications is greatest in the first 3 to 6 months after a diagnosed event, at least 3 months anticoagulation therapy is recommended following VTE diagnosis. At the 3-month mark, all regimens are suggested to be re-evaluated and considered for extended treatment duration if the event was unprovoked, recurrent, secondary to a persistent risk factor, or low bleed risk.²Anticoagulation is an important guideline-recommended pharmacologic intervention for various disease states, although its use is not without risks. The Institute for Safe Medication Practices has classified oral anticoagulants as high-alert medications. This designation was made because anticoagulant medications have the potential to cause harm when used or omitted in error and lead to life-threatening bleed or thrombotic complications.³Anticoagulation stewardship ensures that anticoagulation therapy is appropriately initiated, maintained, and discontinued when indicated. Because of the potential for harm, anticoagulation stewardship is an important part of Afib and VTE management. Pharmacists can help verify and evaluate anticoagulation therapies. Research suggests that pharmacist-led anticoagulation stewardship efforts may play a role in ensuring safer patient outcomes.⁴The purpose of this quality improvement (QI) study was to implement pharmacist-led anticoagulation stewardship practices at Veterans Affairs Phoenix Health Care System (VAPHCS) to identify veterans with Afib not currently on anticoagulation, as well as to identify veterans with a history of VTE events who have completed a sufficient treatment duration.

Methods

Anticoagulation stewardship efforts were implemented in 2 cohorts of patients: those with Afib who may be indicated to initiate anticoagulation, and those with a history of VTE events who may be indicated to consider anticoagulation discontinuation. Patient records were reviewed using a standardized note template, and recommendations to either initiate or discontinue anticoagulation therapy were documented. The VAPHCS Research Service reviewed this study and determined that it was not research and was exempt from institutional review board review.

Atrial Fibrillation Cohort

A population health dashboard created by the Stroke Prevention in Atrial Fibrillation/Flutter Targeting the uNTreated: a focus on health care disparities (SPAFF-TNT-D) national VA study team was used to identify veterans at VAPHCS with a diagnosis of Afib without an active VA prescription for an anticoagulant. The dashboard filtered and produced data points from the medical record that correlated to the components of the CHA₂DS₂-VASc score. All veterans identified by the dashboard with scores of 7 or 8 were included. No patients had a score of 9. Comprehensive chart reviews of available VA and non–VA-provided care records were conducted by the investigators, and a standardized note template designed by the SPAFF-TNT-D team (eAppendix 1) was used to document findings within the electronic health record (EHR). If anticoagulation was deemed to be indicated, the assigned primary care practitioner (PCP) as listed in the EHR was alerted to the note by the investigators for further evaluation and consideration of prescribing anticoagulation.

Venous Thromboembolism Cohort

VAPHCS pharmacy informatics pulled data that included veterans with documented VTE and an active VA anticoagulant prescription between November 2022 and November 2023. Veterans were reviewed in chronological order based on when the anticoagulant prescription was written. All veterans were included until an equal number of charts were reviewed in both the Afib and VTE cohorts. Comprehensive chart review of available VA- and non–VA-provided care records was conducted by the investigators, and a standardized note template as designed by the investigators (eAppendix 2) was used to document findings within the EHR. If the duration of anticoagulation therapy was deemed sufficient, the assigned anticoagulation clinical pharmacist practitioner (CPP) was alerted to the note by the investigators for further evaluation and consideration of discontinuing anticoagulation.

EHR reviews were conducted in October and November 2023 and lasted about 10 to 20 minutes per patient. To evaluate completeness and accuracy of the documented findings within the EHR, both investigators reviewed and cosigned the completed note template and verified the correct PCP was alerted to the recommendation for appropriate continuity of care. Results were reviewed in March 2024.

Outcomes

Atrial fibrillation cohort. The primary outcome was the number of veterans with Afib who were recommended to start anticoagulation therapy. Additional outcomes evaluated included the number of interventions completed, action taken by PCPs in response to the provided recommendation, and reasons provided by the investigators for not recommending initiation of anticoagulation therapy in specific veteran cases.

Venous thromboembolism cohort. The primary outcome was the number of veterans with a history of VTE events recommended to discontinue anticoagulation therapy. Additional outcomes included number of interventions completed, action taken by the anticoagulation CPP in response to the provided recommendation, and reasons provided by the investigators for not recommending discontinuation of anticoagulation therapy in specific veteran cases.

Analysis

Sample size was determined by the inclusion criteria and was not designed to attain statistical power. Data embedded in the Afib cohort standardized note template, also known as health factors, were later used for data analysis. Recommendations in the VTE cohort were manually tracked and recorded by the investigators. Results for this study were analyzed using descriptive statistics.

Results

A total of 114 veterans were reviewed and included in this study: 57 in each cohort. Seven recommendations were made regarding anticoagulation initiation for patients with Afib and 7 were made for anticoagulation discontinuation for patients with VTE (Table 1).

In the Afib cohort, 1 veteran was successfully initiated on anticoagulation therapy and 1 veteran was deemed appropriate for initiation of anticoagulation but was not reachable. Of the 5 recommendations with no action taken, 4 PCPs acknowledged the alert with no further documentation, and 1 PCP deferred the decision to cardiology with no further documentation. In the VTE cohort, 3 veterans successfully discontinued anticoagulation therapy and 2 veterans were further evaluated by the anticoagulation CPP and deemed appropriate to continue therapy based on potential for malignancy. Of the 2 recommendations with no action taken, 1 anticoagulation CPP acknowledged the alert with no further documentation and 1 anticoagulation CPP suggested further evaluation by PCP with no further documentation.

In the Afib cohort, a nonpharmacologic approach was defined as documentation of a LAAO device. An inaccurate diagnosis was defined as an Afib diagnosis being used in a previous visit, although there was no further confirmation of diagnosis via chart review. Veterans classified as already being on anticoagulation had documentation of non–VA-written anticoagulant prescriptions or receiving a supply of anticoagulants from a facility such as a nursing home. Anticoagulation was defined as unfavorable if a documented risk/benefit conversation was found via EHR review. Anticoagulation was defined as not indicated if the Afib was documented as transient, episodic, or historical (Table 2).

In the VTE cohort, no recommendations for discontinuation were made for veterans indicated to continue anticoagulation due to a concurrent Afib diagnosis. Chronic or recurrent events were defined as documentation of multiple VTE events and associated dates in the EHR. Persistent risk factors included malignancy or medications contributing to hypercoagulable states. Thrombophilia was defined as having documentation of a diagnosis in the EHR. An unprovoked event was defined as VTE without any documented transient risk factors (eg, hospitalization, trauma, surgery, cast immobilization, hormone therapy, pregnancy, or prolonged travel). Anticoagulation had already been discontinued in 1 veteran after the data were collected but before chart review occurred (Table 3).

Discussion

Pharmacy-led indication reviews resulted in appropriate recommendations for anticoagulation use in veterans with Afib and a history of VTE events. Overall, 12.3% of chart reviews in each cohort resulted in a recommendation being made, which was similar to the rate found by Koolian et al.⁵ In that study, 10% of recommendations were related to initiation or interruption of anticoagulation. This recommendation category consisted of several subcategories, including “suggesting therapeutic anticoagulation when none is currently ordered” and “suggesting anticoagulation cessation if no longer indicated,” but specific numerical prevalence was not provided.⁵

Online dashboard use allowed for greater population health management and identification of veterans with Afib who were not on active anticoagulation, providing opportunities to prevent stroke-related complications. Wang et al completed a similarly designed study that included a population health tool to identify patients with Afib who were not on anticoagulation and implemented pharmacist-led chart review and facilitation of recommendations to the responsible clinician. This study reviewed 1727 patients and recommended initiation of anticoagulation therapy for 75 (4.3%).⁶ The current study had a higher percentage of patients with recommendations for changes despite its smaller size.

Evaluating the duration of therapy for anticoagulation in veterans with a history of VTE events provided an opportunity to reduce unnecessary exposure to anticoagulation and minimize bleeding risks. Using a chart review process and standardized note template enabled the documentation of pertinent information that could be readily reviewed by the PCP. This process is a step toward ensuring VAPHCS PCPs provide guideline-recommended care and actively prevent stroke and bleeding complications. Adoption of this process into the current VAPHCS Anticoagulation Clinic workflow for review of veterans with either Afib or VTE could lead to more EHRs being reviewed and recommendations made, ultimately improving patient outcomes. 

Therapeutic interventions based on the recommendations were completed for 1 of 7 veterans (14%) and 3 of 7 veterans (43%) in the Afib and VTE cohorts, respectively. The prevalence of completed interventions in this anticoagulation stewardship study was higher than those in Wang et al, who found only 9% of their recommendations resulted in PCPs considering action related to anticoagulation, and only 4% were successfully initiated.⁶

In the Afib cohort, veterans identified by the dashboard with a CHA₂DS₂-VASc of 7 or 8 were prioritized for review. Reviewing these veterans ensured that patients with the highest stroke risk were sufficiently evaluated and started on anticoagulation as needed to reduce stroke-related complications. In contrast, because these veterans had higher CHA₂DS₂-VASc scores, they may have already been evaluated for anticoagulation in the past and had a documented rationale for not being placed on anticoagulation (LAAO device placement was the most common rationale). Focusing on veterans with a lower CHA₂DS₂-VASc score such as 1 for men or 2 for women could potentially include more opportunities for recommendations. Although stroke risk may be lower in this population compared with those with higher CHA₂DS₂-VASc scores, guideline-recommended anticoagulation use may be missed for these patients. 

In the VTE cohort, veterans with an anticoagulant prescription written 12 months before data collection were prioritized for review. Reviewing these veterans ensured that anticoagulation therapy met guideline recommendations of at least 3 months, with potential for extended duration upon further evaluation by a provider at that time. Based on collected results, most veterans were already reevaluated and had documented reasons why anticoagulation was still indicated; concurrent Afib was most common followed by chronic or recurrent VTE. Reviewing veterans with more recent prescriptions just over the recommended 3-month duration could potentially include more opportunities for recommendations to be made. It is more likely that by 3 months another PCP had not already weighed in on the duration of therapy, and the anticoagulation CPP could ensure a thorough review is conducted with guideline-based recommendations.

Most published literature on anticoagulation stewardship efforts is focused on inpatient management and policy changes, or concentrate on attributes of therapy such as appropriate dosing and drug interactions. This study highlighted that gaps in care related to anticoagulation use and discontinuation are present in the VAPHCS population and can be appropriately addressed via pharmacist-led indication reviews. Future studies designed to focus on initiating anticoagulation where appropriate, and discontinuing where a sufficient treatment period has been completed, are warranted to minimize this gap in care and allow health systems to work toward process changes to ensure safe and optimized care is provided for the patients they serve.

Limitations

In the Afib cohort, 5 of 7 recommendations (71%) had no further action taken by the PCP, which may represent a barrier to care. In contrast, 2 of 7 recommendations (29%) had no further action in the VTE cohort. It is possible that the difference can be attributed to the anticoagulation CPP receiving VTE alerts and PCPs receiving Afib alerts. The anticoagulation CPP was familiar with this QI study and may have better understood the purpose of the chart review and the need to provide a timely response. PCPs may have been less likely to take action because they were unfamiliar with the anticoagulation stewardship initiative and standardized note template or overwhelmed by too many EHR alerts.

The lack of PCP response to a virtual alert or message also was observed by Wang et al, whereas Koolian et al reported higher intervention completion rates, with verbal recommendations being made to the responsible clinicians. To further ensure these pertinent recommendations for anticoagulation initiation in veterans with Afib are properly reviewed and evaluated, future research could include intentional follow-up with the PCP regarding the alert, PCP-specific education about the anticoagulation stewardship initiative and the role of the standardized note template, and collaboration with PCPs to identify alternative ways to relay recommendations in a way that would ensure the completion of appropriate and timely review.

Conclusions

This study identified gaps in care related to anticoagulation needs in the VAPHCS veteran population. Utilizing a standardized indication review process allows pharmacists to evaluate anticoagulant use for both appropriate indication and duration of therapy. Providing recommendations via chart review notes and alerting respective PCPs and CPPs results in veterans receiving safe and optimized care regarding their anticoagulation needs.

After the American Academy of Pediatrics (AAP) began recommending vitamin K shots for newborns in 1961, infant bleeding as a result of vitamin K deficiency plummeted. The life-threatening disorder is so rare that some parents now question the need for injections to safeguard against it.

The situation amounts to “a failure of our success,” Ivan Hand, MD, a coauthor of a new AAP statement on vitamin K, told this news organization. Much like diseases that can be prevented with vaccines, vitamin K deficiency bleeding isn’t top of mind for parents. “It’s not something they’re aware of or afraid of,” he said.

In 2019, however, the AAP listed public education about the importance of the shots in its 10 most important priorities.

The policy update urges clinicians to bone up on the benefits and perceived risks of vitamin K deficiency, which is essential for clotting, and to “strongly advocate” for the shot in discussions with parents who may get competing messages from their social circles, the internet, and other health care professionals.

Dr. Hand, director of neonatology at NYC Health + Hospitals Kings County, Brooklyn, said clinicians walk a line between educating and alienating parents who favor natural birth processes. “We’re hoping that by talking to the families and answering their questions and explaining the risks, parents will accept vitamin K as a necessary treatment for their babies,” he said.

Vitamin K does not easily pass through the placenta and is not plentiful in breast milk, the preferred nutrition source for newborns. It takes months for babies to build their stores through food and gut bacteria.

Infants who do not receive vitamin K at birth are 81 times more likely to develop late-onset vitamin K deficiency bleeding, which occurs a week to 6 months after birth, according to the Centers for Disease Control and Prevention. One in five babies with the disorder dies, and about half have bleeding in the skull that can lead to brain damage.
 

New dosing for premature infants

The AAP’s new statement, published in the journal Pediatrics, reaffirms the administration of a 1-mg intramuscular dose for infants weighing more than 1,500 grams, or about 3 lb 5 oz, within 6 hours of birth. For premature infants who weigh less, the guidance recommends an intramuscular dose of 0.3 to 0.5 mg/kg.

The group notes that oral preparations of vitamin K have proven less effective because of malabsorption and challenges with adhering to dosing regimens.

The document also warns that breastfed babies can experience vitamin K deficiency bleeding even if they have received the shot, because concentration of vitamin K often wanes before a baby starts eating solid food. The disorder “should be considered when evaluating bleeding in the first 6 months of life, even in infants who received prophylaxis, and especially in exclusively breastfed infants,” it states.

Accounts of parental refusals date back to 2013, when the CDC reported four cases of deficiency bleeding in Tennessee. The infants’ parents said they declined vitamin K because they worried about increased risk of leukemia, thought the injection was unnecessary, or wanted to minimize the baby’s exposure to “toxins.” Leukemia concern stemmed from a 1992 report linking vitamin K to childhood cancer, an association that did not hold up in subsequent studies.

More recent research has documented parental concerns about preservatives and injection pain as well as distrust of medical and public health authorities. Some parents have been accused of neglect for refusing to allow their babies to receive the shots.  

Phoebe Danziger, MD, a pediatrician and writer in rural Michigan who has studied parental refusal of standard-of-care interventions, called the document a “welcome update” to the AAP’s last statement on the topic, in 2003. She told this news organization that lower dosing for premature infants may reassure some vitamin K–hesitant parents who worry about one-size-fits-all dosing.

But Dr. Danziger added that “evidence is lacking to support the claim that pediatricians can really move the needle on parental hesitancy and refusal simply through better listening and more persuasive counseling.” She said the AAP should do more to address “the broader social climate of mistrust and misinformation” that fuels refusal.

Dr. Hand and Dr. Danziger have disclosed no relevant financial relationships.

A version of this article first appeared on Medscape.com.

After the American Academy of Pediatrics (AAP) began recommending vitamin K shots for newborns in 1961, infant bleeding as a result of vitamin K deficiency plummeted. The life-threatening disorder is so rare that some parents now question the need for injections to safeguard against it.

The situation amounts to “a failure of our success,” Ivan Hand, MD, a coauthor of a new AAP statement on vitamin K, told this news organization. Much like diseases that can be prevented with vaccines, vitamin K deficiency bleeding isn’t top of mind for parents. “It’s not something they’re aware of or afraid of,” he said.

In 2019, however, the AAP listed public education about the importance of the shots in its 10 most important priorities.

The policy update urges clinicians to bone up on the benefits and perceived risks of vitamin K deficiency, which is essential for clotting, and to “strongly advocate” for the shot in discussions with parents who may get competing messages from their social circles, the internet, and other health care professionals.

Dr. Hand, director of neonatology at NYC Health + Hospitals Kings County, Brooklyn, said clinicians walk a line between educating and alienating parents who favor natural birth processes. “We’re hoping that by talking to the families and answering their questions and explaining the risks, parents will accept vitamin K as a necessary treatment for their babies,” he said.

Vitamin K does not easily pass through the placenta and is not plentiful in breast milk, the preferred nutrition source for newborns. It takes months for babies to build their stores through food and gut bacteria.

Infants who do not receive vitamin K at birth are 81 times more likely to develop late-onset vitamin K deficiency bleeding, which occurs a week to 6 months after birth, according to the Centers for Disease Control and Prevention. One in five babies with the disorder dies, and about half have bleeding in the skull that can lead to brain damage.
 

New dosing for premature infants

The AAP’s new statement, published in the journal Pediatrics, reaffirms the administration of a 1-mg intramuscular dose for infants weighing more than 1,500 grams, or about 3 lb 5 oz, within 6 hours of birth. For premature infants who weigh less, the guidance recommends an intramuscular dose of 0.3 to 0.5 mg/kg.

The group notes that oral preparations of vitamin K have proven less effective because of malabsorption and challenges with adhering to dosing regimens.

The document also warns that breastfed babies can experience vitamin K deficiency bleeding even if they have received the shot, because concentration of vitamin K often wanes before a baby starts eating solid food. The disorder “should be considered when evaluating bleeding in the first 6 months of life, even in infants who received prophylaxis, and especially in exclusively breastfed infants,” it states.

Accounts of parental refusals date back to 2013, when the CDC reported four cases of deficiency bleeding in Tennessee. The infants’ parents said they declined vitamin K because they worried about increased risk of leukemia, thought the injection was unnecessary, or wanted to minimize the baby’s exposure to “toxins.” Leukemia concern stemmed from a 1992 report linking vitamin K to childhood cancer, an association that did not hold up in subsequent studies.

More recent research has documented parental concerns about preservatives and injection pain as well as distrust of medical and public health authorities. Some parents have been accused of neglect for refusing to allow their babies to receive the shots.  

Phoebe Danziger, MD, a pediatrician and writer in rural Michigan who has studied parental refusal of standard-of-care interventions, called the document a “welcome update” to the AAP’s last statement on the topic, in 2003. She told this news organization that lower dosing for premature infants may reassure some vitamin K–hesitant parents who worry about one-size-fits-all dosing.

But Dr. Danziger added that “evidence is lacking to support the claim that pediatricians can really move the needle on parental hesitancy and refusal simply through better listening and more persuasive counseling.” She said the AAP should do more to address “the broader social climate of mistrust and misinformation” that fuels refusal.

Dr. Hand and Dr. Danziger have disclosed no relevant financial relationships.

A version of this article first appeared on Medscape.com.

After the American Academy of Pediatrics (AAP) began recommending vitamin K shots for newborns in 1961, infant bleeding as a result of vitamin K deficiency plummeted. The life-threatening disorder is so rare that some parents now question the need for injections to safeguard against it.

The situation amounts to “a failure of our success,” Ivan Hand, MD, a coauthor of a new AAP statement on vitamin K, told this news organization. Much like diseases that can be prevented with vaccines, vitamin K deficiency bleeding isn’t top of mind for parents. “It’s not something they’re aware of or afraid of,” he said.

In 2019, however, the AAP listed public education about the importance of the shots in its 10 most important priorities.

The policy update urges clinicians to bone up on the benefits and perceived risks of vitamin K deficiency, which is essential for clotting, and to “strongly advocate” for the shot in discussions with parents who may get competing messages from their social circles, the internet, and other health care professionals.

Dr. Hand, director of neonatology at NYC Health + Hospitals Kings County, Brooklyn, said clinicians walk a line between educating and alienating parents who favor natural birth processes. “We’re hoping that by talking to the families and answering their questions and explaining the risks, parents will accept vitamin K as a necessary treatment for their babies,” he said.

Vitamin K does not easily pass through the placenta and is not plentiful in breast milk, the preferred nutrition source for newborns. It takes months for babies to build their stores through food and gut bacteria.

Infants who do not receive vitamin K at birth are 81 times more likely to develop late-onset vitamin K deficiency bleeding, which occurs a week to 6 months after birth, according to the Centers for Disease Control and Prevention. One in five babies with the disorder dies, and about half have bleeding in the skull that can lead to brain damage.
 

New dosing for premature infants

The AAP’s new statement, published in the journal Pediatrics, reaffirms the administration of a 1-mg intramuscular dose for infants weighing more than 1,500 grams, or about 3 lb 5 oz, within 6 hours of birth. For premature infants who weigh less, the guidance recommends an intramuscular dose of 0.3 to 0.5 mg/kg.

The group notes that oral preparations of vitamin K have proven less effective because of malabsorption and challenges with adhering to dosing regimens.

The document also warns that breastfed babies can experience vitamin K deficiency bleeding even if they have received the shot, because concentration of vitamin K often wanes before a baby starts eating solid food. The disorder “should be considered when evaluating bleeding in the first 6 months of life, even in infants who received prophylaxis, and especially in exclusively breastfed infants,” it states.

Accounts of parental refusals date back to 2013, when the CDC reported four cases of deficiency bleeding in Tennessee. The infants’ parents said they declined vitamin K because they worried about increased risk of leukemia, thought the injection was unnecessary, or wanted to minimize the baby’s exposure to “toxins.” Leukemia concern stemmed from a 1992 report linking vitamin K to childhood cancer, an association that did not hold up in subsequent studies.

More recent research has documented parental concerns about preservatives and injection pain as well as distrust of medical and public health authorities. Some parents have been accused of neglect for refusing to allow their babies to receive the shots.  

Phoebe Danziger, MD, a pediatrician and writer in rural Michigan who has studied parental refusal of standard-of-care interventions, called the document a “welcome update” to the AAP’s last statement on the topic, in 2003. She told this news organization that lower dosing for premature infants may reassure some vitamin K–hesitant parents who worry about one-size-fits-all dosing.

But Dr. Danziger added that “evidence is lacking to support the claim that pediatricians can really move the needle on parental hesitancy and refusal simply through better listening and more persuasive counseling.” She said the AAP should do more to address “the broader social climate of mistrust and misinformation” that fuels refusal.

Dr. Hand and Dr. Danziger have disclosed no relevant financial relationships.

A version of this article first appeared on Medscape.com.

Antithrombotic therapy in clinically stable, nonhospitalized COVID-19 patients does not offer protection against adverse cardiovascular or pulmonary events, new randomized clinical trial results suggest.

Bruce Jancin/MDedge News

Antithrombotic therapy has proven useful in acutely ill inpatients with COVID-19, but in this study, treatment with aspirin or apixaban (Eliquis) did not reduce the rate of all-cause mortality, symptomatic venous or arterial thromboembolism, myocardial infarction, stroke, or hospitalization for cardiovascular or pulmonary causes in patients ill with COVID-19 but who were not hospitalized.

“Among symptomatic, clinically stable outpatients with COVID-19, treatment with aspirin or apixaban compared with placebo did not reduce the rate of a composite clinical outcome,” the authors conclude. “However, the study was terminated after enrollment of 9% of participants because of a primary event rate lower than anticipated.”

The study, which was led by Jean M. Connors, MD, Brigham and Women’s Hospital, Boston, was published online October 11 in JAMA.

The ACTIV-4B Outpatient Thrombosis Prevention Trial was a randomized, adaptive, double-blind, placebo-controlled trial that sought to compare anticoagulant and antiplatelet therapy among 7,000 symptomatic but clinically stable outpatients with COVID-19.

The trial was conducted at 52 sites in the U.S. between Sept. 2020 and June 2021, with final follow-up this past August 5, and involved minimal face-to-face interactions with study participants.

Patients were randomized in a 1:1:1:1 ratio to aspirin (81 mg orally once daily; n = 164 patients), prophylactic-dose apixaban (2.5 mg orally twice daily; n = 165), therapeutic-dose apixaban (5 mg orally twice daily; n = 164), or placebo (n = 164) for 45 days.

The primary endpoint was a composite of all-cause mortality, symptomatic venous or arterial thromboembolism, myocardial infarction, stroke, or hospitalization for cardiovascular or pulmonary cause.

The trial was terminated early this past June by the independent data monitoring committee because of lower than anticipated event rates. At the time, just 657 symptomatic outpatients with COVID-19 had been enrolled.

The median age of the study participants was 54 years (Interquartile Range [IQR] 46-59); 59% were women.

The median time from diagnosis to randomization was 7 days, and the median time from randomization to initiation of study medications was 3 days.

The trial’s primary efficacy and safety analyses were restricted to patients who received at least one dose of trial medication, for a final number of 558 patients.

Among these patients, the primary endpoint occurred in 1 patient (0.7%) in the aspirin group, 1 patient (0.7%) in the 2.5 mg apixaban group, 2 patients (1.4%) in the 5-mg apixaban group, and 1 patient (0.7%) in the placebo group.

The researchers found that the absolute risk reductions compared with placebo for the primary outcome were 0.0% (95% confidence interval not calculable) in the aspirin group, 0.7% (95% confidence interval, -2.1% to 4.1%) in the prophylactic-dose apixaban group, and 1.4% (95% CI, -1.5% to 5%) in the therapeutic-dose apixaban group.

No major bleeding events were reported.

The absolute risk differences compared with placebo for clinically relevant nonmajor bleeding events were 2% (95% CI, -2.7% to 6.8%) in the aspirin group, 4.5% (95% CI, -0.7% to 10.2%) in the prophylactic-dose apixaban group, and 6.9% (95% CI, 1.4% to 12.9%) in the therapeutic-dose apixaban group.

Safety and efficacy results were similar in all randomly assigned patients.

The researchers speculated that a combination of two demographic shifts over time may have led to the lower than anticipated rate of events in ACTIV-4B.

“First, the threshold for hospital admission has markedly declined since the beginning of the pandemic, such that hospitalization is no longer limited almost exclusively to those with severe pulmonary distress likely to require mechanical ventilation,” they write. “As a result, the severity of illness among individuals with COVID-19 and destined for outpatient care has declined.”

“Second, at least within the U.S., where the trial was conducted, individuals currently being infected with SARS-CoV-2 tend to be younger and have fewer comorbidities when compared with individuals with incident infection at the onset of the pandemic,” they add.

Further, COVID-19 testing was quite limited early in the pandemic, they note, “and it is possible that the anticipated event rates based on data from registries available at that time were overestimated because the denominator (that is, the number of infected individuals overall) was essentially unknown.”
 

Robust evidence

“The ACTIV-4B trial is the first randomized trial to generate robust evidence about the effects of antithrombotic therapy in outpatients with COVID-19,” Otavio Berwanger, MD, PhD, director of the Academic Research Organization, Hospital Israelita Albert Einstein, Sao Paulo-SP, Brazil, told this news organization.

“It should be noted that this was a well-designed trial with low risk of bias. On the other hand, the main limitation is the low number of events and, consequently, the limited statistical power,” said Dr. Berwanger, who wrote an accompanying editorial.

The ACTIV-4B trial has immediate implications for clinical practice, he added.

“In this sense, considering the neutral results for major cardiopulmonary outcomes, the use of aspirin or apixaban for the management of outpatients with COVID-19 should not be recommended.”

ACTIV-4B also provides useful information for the steering committees of other ongoing trials of antithrombotic therapy for patients with COVID-19 who are not hospitalized, Dr. Berwanger added.

“In this sense, probably issues like statistical power, outcome choices, recruitment feasibility, and even futility would need to be revisited. And finally, lessons learned from the implementation of an innovative, pragmatic, and decentralized trial design represent an important legacy for future trials in cardiovascular diseases and other common conditions,” he said.

The study was funded by the National Institutes of Health, and the National Heart, Lung, and Blood Institute. Dr. Connors reports financial relationships with Bristol-Myers Squibb, Pfizer, Abbott, Alnylam, Takeda, Roche, and Sanofi. Dr. Berwanger reports financial relationships with AstraZeneca, Amgen, Servier, Bristol-Myers Squibb, Bayer, Novartis, Pfizer, and Boehringer Ingelheim.

A version of this article first appeared on Medscape.com.

Antithrombotic therapy in clinically stable, nonhospitalized COVID-19 patients does not offer protection against adverse cardiovascular or pulmonary events, new randomized clinical trial results suggest.

Bruce Jancin/MDedge News

Antithrombotic therapy has proven useful in acutely ill inpatients with COVID-19, but in this study, treatment with aspirin or apixaban (Eliquis) did not reduce the rate of all-cause mortality, symptomatic venous or arterial thromboembolism, myocardial infarction, stroke, or hospitalization for cardiovascular or pulmonary causes in patients ill with COVID-19 but who were not hospitalized.

“Among symptomatic, clinically stable outpatients with COVID-19, treatment with aspirin or apixaban compared with placebo did not reduce the rate of a composite clinical outcome,” the authors conclude. “However, the study was terminated after enrollment of 9% of participants because of a primary event rate lower than anticipated.”

The study, which was led by Jean M. Connors, MD, Brigham and Women’s Hospital, Boston, was published online October 11 in JAMA.

The ACTIV-4B Outpatient Thrombosis Prevention Trial was a randomized, adaptive, double-blind, placebo-controlled trial that sought to compare anticoagulant and antiplatelet therapy among 7,000 symptomatic but clinically stable outpatients with COVID-19.

The trial was conducted at 52 sites in the U.S. between Sept. 2020 and June 2021, with final follow-up this past August 5, and involved minimal face-to-face interactions with study participants.

Patients were randomized in a 1:1:1:1 ratio to aspirin (81 mg orally once daily; n = 164 patients), prophylactic-dose apixaban (2.5 mg orally twice daily; n = 165), therapeutic-dose apixaban (5 mg orally twice daily; n = 164), or placebo (n = 164) for 45 days.

The primary endpoint was a composite of all-cause mortality, symptomatic venous or arterial thromboembolism, myocardial infarction, stroke, or hospitalization for cardiovascular or pulmonary cause.

The trial was terminated early this past June by the independent data monitoring committee because of lower than anticipated event rates. At the time, just 657 symptomatic outpatients with COVID-19 had been enrolled.

The median age of the study participants was 54 years (Interquartile Range [IQR] 46-59); 59% were women.

The median time from diagnosis to randomization was 7 days, and the median time from randomization to initiation of study medications was 3 days.

The trial’s primary efficacy and safety analyses were restricted to patients who received at least one dose of trial medication, for a final number of 558 patients.

Among these patients, the primary endpoint occurred in 1 patient (0.7%) in the aspirin group, 1 patient (0.7%) in the 2.5 mg apixaban group, 2 patients (1.4%) in the 5-mg apixaban group, and 1 patient (0.7%) in the placebo group.

The researchers found that the absolute risk reductions compared with placebo for the primary outcome were 0.0% (95% confidence interval not calculable) in the aspirin group, 0.7% (95% confidence interval, -2.1% to 4.1%) in the prophylactic-dose apixaban group, and 1.4% (95% CI, -1.5% to 5%) in the therapeutic-dose apixaban group.

No major bleeding events were reported.

The absolute risk differences compared with placebo for clinically relevant nonmajor bleeding events were 2% (95% CI, -2.7% to 6.8%) in the aspirin group, 4.5% (95% CI, -0.7% to 10.2%) in the prophylactic-dose apixaban group, and 6.9% (95% CI, 1.4% to 12.9%) in the therapeutic-dose apixaban group.

Safety and efficacy results were similar in all randomly assigned patients.

The researchers speculated that a combination of two demographic shifts over time may have led to the lower than anticipated rate of events in ACTIV-4B.

“First, the threshold for hospital admission has markedly declined since the beginning of the pandemic, such that hospitalization is no longer limited almost exclusively to those with severe pulmonary distress likely to require mechanical ventilation,” they write. “As a result, the severity of illness among individuals with COVID-19 and destined for outpatient care has declined.”

“Second, at least within the U.S., where the trial was conducted, individuals currently being infected with SARS-CoV-2 tend to be younger and have fewer comorbidities when compared with individuals with incident infection at the onset of the pandemic,” they add.

Further, COVID-19 testing was quite limited early in the pandemic, they note, “and it is possible that the anticipated event rates based on data from registries available at that time were overestimated because the denominator (that is, the number of infected individuals overall) was essentially unknown.”
 

Robust evidence

“The ACTIV-4B trial is the first randomized trial to generate robust evidence about the effects of antithrombotic therapy in outpatients with COVID-19,” Otavio Berwanger, MD, PhD, director of the Academic Research Organization, Hospital Israelita Albert Einstein, Sao Paulo-SP, Brazil, told this news organization.

“It should be noted that this was a well-designed trial with low risk of bias. On the other hand, the main limitation is the low number of events and, consequently, the limited statistical power,” said Dr. Berwanger, who wrote an accompanying editorial.

The ACTIV-4B trial has immediate implications for clinical practice, he added.

“In this sense, considering the neutral results for major cardiopulmonary outcomes, the use of aspirin or apixaban for the management of outpatients with COVID-19 should not be recommended.”

ACTIV-4B also provides useful information for the steering committees of other ongoing trials of antithrombotic therapy for patients with COVID-19 who are not hospitalized, Dr. Berwanger added.

“In this sense, probably issues like statistical power, outcome choices, recruitment feasibility, and even futility would need to be revisited. And finally, lessons learned from the implementation of an innovative, pragmatic, and decentralized trial design represent an important legacy for future trials in cardiovascular diseases and other common conditions,” he said.

The study was funded by the National Institutes of Health, and the National Heart, Lung, and Blood Institute. Dr. Connors reports financial relationships with Bristol-Myers Squibb, Pfizer, Abbott, Alnylam, Takeda, Roche, and Sanofi. Dr. Berwanger reports financial relationships with AstraZeneca, Amgen, Servier, Bristol-Myers Squibb, Bayer, Novartis, Pfizer, and Boehringer Ingelheim.

A version of this article first appeared on Medscape.com.

Antithrombotic therapy in clinically stable, nonhospitalized COVID-19 patients does not offer protection against adverse cardiovascular or pulmonary events, new randomized clinical trial results suggest.

Bruce Jancin/MDedge News

Antithrombotic therapy has proven useful in acutely ill inpatients with COVID-19, but in this study, treatment with aspirin or apixaban (Eliquis) did not reduce the rate of all-cause mortality, symptomatic venous or arterial thromboembolism, myocardial infarction, stroke, or hospitalization for cardiovascular or pulmonary causes in patients ill with COVID-19 but who were not hospitalized.

“Among symptomatic, clinically stable outpatients with COVID-19, treatment with aspirin or apixaban compared with placebo did not reduce the rate of a composite clinical outcome,” the authors conclude. “However, the study was terminated after enrollment of 9% of participants because of a primary event rate lower than anticipated.”

The study, which was led by Jean M. Connors, MD, Brigham and Women’s Hospital, Boston, was published online October 11 in JAMA.

The ACTIV-4B Outpatient Thrombosis Prevention Trial was a randomized, adaptive, double-blind, placebo-controlled trial that sought to compare anticoagulant and antiplatelet therapy among 7,000 symptomatic but clinically stable outpatients with COVID-19.

The trial was conducted at 52 sites in the U.S. between Sept. 2020 and June 2021, with final follow-up this past August 5, and involved minimal face-to-face interactions with study participants.

Patients were randomized in a 1:1:1:1 ratio to aspirin (81 mg orally once daily; n = 164 patients), prophylactic-dose apixaban (2.5 mg orally twice daily; n = 165), therapeutic-dose apixaban (5 mg orally twice daily; n = 164), or placebo (n = 164) for 45 days.

The primary endpoint was a composite of all-cause mortality, symptomatic venous or arterial thromboembolism, myocardial infarction, stroke, or hospitalization for cardiovascular or pulmonary cause.

The trial was terminated early this past June by the independent data monitoring committee because of lower than anticipated event rates. At the time, just 657 symptomatic outpatients with COVID-19 had been enrolled.

The median age of the study participants was 54 years (Interquartile Range [IQR] 46-59); 59% were women.

The median time from diagnosis to randomization was 7 days, and the median time from randomization to initiation of study medications was 3 days.

The trial’s primary efficacy and safety analyses were restricted to patients who received at least one dose of trial medication, for a final number of 558 patients.

Among these patients, the primary endpoint occurred in 1 patient (0.7%) in the aspirin group, 1 patient (0.7%) in the 2.5 mg apixaban group, 2 patients (1.4%) in the 5-mg apixaban group, and 1 patient (0.7%) in the placebo group.

The researchers found that the absolute risk reductions compared with placebo for the primary outcome were 0.0% (95% confidence interval not calculable) in the aspirin group, 0.7% (95% confidence interval, -2.1% to 4.1%) in the prophylactic-dose apixaban group, and 1.4% (95% CI, -1.5% to 5%) in the therapeutic-dose apixaban group.

No major bleeding events were reported.

The absolute risk differences compared with placebo for clinically relevant nonmajor bleeding events were 2% (95% CI, -2.7% to 6.8%) in the aspirin group, 4.5% (95% CI, -0.7% to 10.2%) in the prophylactic-dose apixaban group, and 6.9% (95% CI, 1.4% to 12.9%) in the therapeutic-dose apixaban group.

Safety and efficacy results were similar in all randomly assigned patients.

The researchers speculated that a combination of two demographic shifts over time may have led to the lower than anticipated rate of events in ACTIV-4B.

“First, the threshold for hospital admission has markedly declined since the beginning of the pandemic, such that hospitalization is no longer limited almost exclusively to those with severe pulmonary distress likely to require mechanical ventilation,” they write. “As a result, the severity of illness among individuals with COVID-19 and destined for outpatient care has declined.”

“Second, at least within the U.S., where the trial was conducted, individuals currently being infected with SARS-CoV-2 tend to be younger and have fewer comorbidities when compared with individuals with incident infection at the onset of the pandemic,” they add.

Further, COVID-19 testing was quite limited early in the pandemic, they note, “and it is possible that the anticipated event rates based on data from registries available at that time were overestimated because the denominator (that is, the number of infected individuals overall) was essentially unknown.”
 

Robust evidence

“The ACTIV-4B trial is the first randomized trial to generate robust evidence about the effects of antithrombotic therapy in outpatients with COVID-19,” Otavio Berwanger, MD, PhD, director of the Academic Research Organization, Hospital Israelita Albert Einstein, Sao Paulo-SP, Brazil, told this news organization.

“It should be noted that this was a well-designed trial with low risk of bias. On the other hand, the main limitation is the low number of events and, consequently, the limited statistical power,” said Dr. Berwanger, who wrote an accompanying editorial.

The ACTIV-4B trial has immediate implications for clinical practice, he added.

“In this sense, considering the neutral results for major cardiopulmonary outcomes, the use of aspirin or apixaban for the management of outpatients with COVID-19 should not be recommended.”

ACTIV-4B also provides useful information for the steering committees of other ongoing trials of antithrombotic therapy for patients with COVID-19 who are not hospitalized, Dr. Berwanger added.

“In this sense, probably issues like statistical power, outcome choices, recruitment feasibility, and even futility would need to be revisited. And finally, lessons learned from the implementation of an innovative, pragmatic, and decentralized trial design represent an important legacy for future trials in cardiovascular diseases and other common conditions,” he said.

The study was funded by the National Institutes of Health, and the National Heart, Lung, and Blood Institute. Dr. Connors reports financial relationships with Bristol-Myers Squibb, Pfizer, Abbott, Alnylam, Takeda, Roche, and Sanofi. Dr. Berwanger reports financial relationships with AstraZeneca, Amgen, Servier, Bristol-Myers Squibb, Bayer, Novartis, Pfizer, and Boehringer Ingelheim.

A version of this article first appeared on Medscape.com.

The incidence of venous thromboembolism (VTE) in nonhospitalized patients with COVID-19 was not significantly different from patients without the infectious disease, according to a new study published in JAMA Internal Medicine.

Design Cells/Getty Images

National Institutes of Health guidelines recommend blood thinners to prevent blood clots in patients hospitalized with COVID-19. However, the new study provides more insight on the best treatment approach for COVID-19 outpatients.

“[COVID-19’s] rapid global progression and impact has caused us to make and modify treatment decisions at a pace that we never have in modern medicine,” study author Nareg Roubinian, MD, an investigator at Kaiser Permanente, Oakland, Calif., said in an interview.

“As with other potential therapies for COVID-19, blood thinners need to be prospectively studied in a clinical trial to determine if they improve patient outcomes,” Dr. Roubinian added.

The increased risk of blood clots in patients hospitalized with COVID-19 has been a major issue throughout the pandemic. In fact, one study published in November 2020 found that more than half of patients hospitalized with the illness have prothrombotic antiphospholipid (aPL) autoantibodies in their blood, which could contribute to venous and arterial thromboembolism.

Although it was clear many hospitalized patients diagnosed with COVID-19 were developing more clots, researchers of the current study were not sure if this trend would also be seen in outpatients.

“Most people with COVID-19 do not need to be hospitalized, and we needed to know how often patients outside the hospital were having blood clots,” said Dr. Roubinian.

For the study, Dr. Roubinian and colleagues examined data on 220,588 patients who were members of Kaiser Permanente Northern California health plan and were tested for COVID-19 between Feb. 25 and Aug. 31, 2020. They then reported on the 30-day incidence of outpatient and hospital-associated blood clots following the COVID-19 diagnosis. Patients who were asymptomatic at the time of testing or had received anticoagulants within the last year were excluded.

“We knew from other studies that patients with COVID-19 often get sicker in the first few weeks after infection. What we didn’t know was whether COVID-19 patients were developing blood clots but not pneumonia or were developing blood clots at the same time as they developed pneumonia,” said Dr. Roubinian, an intensive care doctor with the Permanente Medical Group in Oakland, Calif. “Following the patients for 30 days allowed us to focus on the time period from infection to when blood clots were most likely to develop.”

Researchers found that of the cohort who took the COVID-19 test, 11.8% had a positive result. Within 30 days of the COVID-19 test, 0.8% of patients with a positive result were diagnosed with VTE compared to 0.5% of those who received a negative test result. They also found that viral testing took place in an outpatient setting for 59.1% of the patients with a positive viral test who later developed VTE. Of those patients, 76.1% had to be hospitalized.

Dr. Roubinian said he was surprised to see that the blood clotting in outpatients with COVID-19 was similar in frequency to what he saw in patients without the infection.

“Our findings suggest that blood clots do occur in COVID-19 patients but not on a scale where we need to put all or many COVID outpatients on blood thinners,” he said. “As with other potential therapies for COVID-19, blood thinners need to be prospectively studied in a clinical trial to determine if they improve patient outcomes.”

In December 2020, three trials investigating the risk and benefits of increased levels of anticoagulation in hospitalized COVID-19 patients were paused because of safety issues. The trials would have enrolled critically ill COVID-19 patients for whom therapeutic doses of anticoagulation drugs showed no benefit.

Anticoagulants are associated with bleeding risks, including prolonged nosebleeds and vomiting or coughing up blood.

Instead of prescribing the routine use of thromboprophylactic drugs to COVID-19 outpatients, Dr. Roubinian believes it would be helpful to learn how to determine whether a patient at risk of becoming sick or being hospitalized would benefit from being treated with such drugs.

Dr. Roubinian reported receiving grants from the National Institutes of Health and the National Heart, Lung, and Blood Institute during the conduct of the study.
 

The incidence of venous thromboembolism (VTE) in nonhospitalized patients with COVID-19 was not significantly different from patients without the infectious disease, according to a new study published in JAMA Internal Medicine.

Design Cells/Getty Images

National Institutes of Health guidelines recommend blood thinners to prevent blood clots in patients hospitalized with COVID-19. However, the new study provides more insight on the best treatment approach for COVID-19 outpatients.

“[COVID-19’s] rapid global progression and impact has caused us to make and modify treatment decisions at a pace that we never have in modern medicine,” study author Nareg Roubinian, MD, an investigator at Kaiser Permanente, Oakland, Calif., said in an interview.

“As with other potential therapies for COVID-19, blood thinners need to be prospectively studied in a clinical trial to determine if they improve patient outcomes,” Dr. Roubinian added.

The increased risk of blood clots in patients hospitalized with COVID-19 has been a major issue throughout the pandemic. In fact, one study published in November 2020 found that more than half of patients hospitalized with the illness have prothrombotic antiphospholipid (aPL) autoantibodies in their blood, which could contribute to venous and arterial thromboembolism.

Although it was clear many hospitalized patients diagnosed with COVID-19 were developing more clots, researchers of the current study were not sure if this trend would also be seen in outpatients.

“Most people with COVID-19 do not need to be hospitalized, and we needed to know how often patients outside the hospital were having blood clots,” said Dr. Roubinian.

For the study, Dr. Roubinian and colleagues examined data on 220,588 patients who were members of Kaiser Permanente Northern California health plan and were tested for COVID-19 between Feb. 25 and Aug. 31, 2020. They then reported on the 30-day incidence of outpatient and hospital-associated blood clots following the COVID-19 diagnosis. Patients who were asymptomatic at the time of testing or had received anticoagulants within the last year were excluded.

“We knew from other studies that patients with COVID-19 often get sicker in the first few weeks after infection. What we didn’t know was whether COVID-19 patients were developing blood clots but not pneumonia or were developing blood clots at the same time as they developed pneumonia,” said Dr. Roubinian, an intensive care doctor with the Permanente Medical Group in Oakland, Calif. “Following the patients for 30 days allowed us to focus on the time period from infection to when blood clots were most likely to develop.”

Researchers found that of the cohort who took the COVID-19 test, 11.8% had a positive result. Within 30 days of the COVID-19 test, 0.8% of patients with a positive result were diagnosed with VTE compared to 0.5% of those who received a negative test result. They also found that viral testing took place in an outpatient setting for 59.1% of the patients with a positive viral test who later developed VTE. Of those patients, 76.1% had to be hospitalized.

Dr. Roubinian said he was surprised to see that the blood clotting in outpatients with COVID-19 was similar in frequency to what he saw in patients without the infection.

“Our findings suggest that blood clots do occur in COVID-19 patients but not on a scale where we need to put all or many COVID outpatients on blood thinners,” he said. “As with other potential therapies for COVID-19, blood thinners need to be prospectively studied in a clinical trial to determine if they improve patient outcomes.”

In December 2020, three trials investigating the risk and benefits of increased levels of anticoagulation in hospitalized COVID-19 patients were paused because of safety issues. The trials would have enrolled critically ill COVID-19 patients for whom therapeutic doses of anticoagulation drugs showed no benefit.

Anticoagulants are associated with bleeding risks, including prolonged nosebleeds and vomiting or coughing up blood.

Instead of prescribing the routine use of thromboprophylactic drugs to COVID-19 outpatients, Dr. Roubinian believes it would be helpful to learn how to determine whether a patient at risk of becoming sick or being hospitalized would benefit from being treated with such drugs.

Dr. Roubinian reported receiving grants from the National Institutes of Health and the National Heart, Lung, and Blood Institute during the conduct of the study.
 

The incidence of venous thromboembolism (VTE) in nonhospitalized patients with COVID-19 was not significantly different from patients without the infectious disease, according to a new study published in JAMA Internal Medicine.

Design Cells/Getty Images

National Institutes of Health guidelines recommend blood thinners to prevent blood clots in patients hospitalized with COVID-19. However, the new study provides more insight on the best treatment approach for COVID-19 outpatients.

“[COVID-19’s] rapid global progression and impact has caused us to make and modify treatment decisions at a pace that we never have in modern medicine,” study author Nareg Roubinian, MD, an investigator at Kaiser Permanente, Oakland, Calif., said in an interview.

“As with other potential therapies for COVID-19, blood thinners need to be prospectively studied in a clinical trial to determine if they improve patient outcomes,” Dr. Roubinian added.

The increased risk of blood clots in patients hospitalized with COVID-19 has been a major issue throughout the pandemic. In fact, one study published in November 2020 found that more than half of patients hospitalized with the illness have prothrombotic antiphospholipid (aPL) autoantibodies in their blood, which could contribute to venous and arterial thromboembolism.

Although it was clear many hospitalized patients diagnosed with COVID-19 were developing more clots, researchers of the current study were not sure if this trend would also be seen in outpatients.

“Most people with COVID-19 do not need to be hospitalized, and we needed to know how often patients outside the hospital were having blood clots,” said Dr. Roubinian.

For the study, Dr. Roubinian and colleagues examined data on 220,588 patients who were members of Kaiser Permanente Northern California health plan and were tested for COVID-19 between Feb. 25 and Aug. 31, 2020. They then reported on the 30-day incidence of outpatient and hospital-associated blood clots following the COVID-19 diagnosis. Patients who were asymptomatic at the time of testing or had received anticoagulants within the last year were excluded.

“We knew from other studies that patients with COVID-19 often get sicker in the first few weeks after infection. What we didn’t know was whether COVID-19 patients were developing blood clots but not pneumonia or were developing blood clots at the same time as they developed pneumonia,” said Dr. Roubinian, an intensive care doctor with the Permanente Medical Group in Oakland, Calif. “Following the patients for 30 days allowed us to focus on the time period from infection to when blood clots were most likely to develop.”

Researchers found that of the cohort who took the COVID-19 test, 11.8% had a positive result. Within 30 days of the COVID-19 test, 0.8% of patients with a positive result were diagnosed with VTE compared to 0.5% of those who received a negative test result. They also found that viral testing took place in an outpatient setting for 59.1% of the patients with a positive viral test who later developed VTE. Of those patients, 76.1% had to be hospitalized.

Dr. Roubinian said he was surprised to see that the blood clotting in outpatients with COVID-19 was similar in frequency to what he saw in patients without the infection.

“Our findings suggest that blood clots do occur in COVID-19 patients but not on a scale where we need to put all or many COVID outpatients on blood thinners,” he said. “As with other potential therapies for COVID-19, blood thinners need to be prospectively studied in a clinical trial to determine if they improve patient outcomes.”

In December 2020, three trials investigating the risk and benefits of increased levels of anticoagulation in hospitalized COVID-19 patients were paused because of safety issues. The trials would have enrolled critically ill COVID-19 patients for whom therapeutic doses of anticoagulation drugs showed no benefit.

Anticoagulants are associated with bleeding risks, including prolonged nosebleeds and vomiting or coughing up blood.

Instead of prescribing the routine use of thromboprophylactic drugs to COVID-19 outpatients, Dr. Roubinian believes it would be helpful to learn how to determine whether a patient at risk of becoming sick or being hospitalized would benefit from being treated with such drugs.

Dr. Roubinian reported receiving grants from the National Institutes of Health and the National Heart, Lung, and Blood Institute during the conduct of the study.
 

Deep vein thrombosis (DVT) is a frequently encountered medical condition with about 1 in 1,000 adults diagnosed annually.^1,2 Up to one-half of patients who receive a diagnosis will experience long-term complications in the affected limb.¹ Anticoagulation is the treatment of choice for DVT in the absence of any contraindications.³ Thrombolytic therapies (eg, systemic thrombolysis, catheter-directed thrombolysis with or without thrombectomy) historically have been reserved for patients who present with phlegmasia cerulea dolens (PCD), a severe condition involving venous obstruction within the extremities that causes impaired arterial blood supply and cyanosis that can lead to limb loss and death.⁴

The role of thrombolytic therapy is less clear in patients without PCD who present with extensive or symptomatic lower extremity DVT that causes significant pain, edema, and functional disability. Proximal lower extremity DVT (thrombus above the knee and above the popliteal vein) and particularly those involving the iliac or common femoral vein (ie, iliofemoral DVT) carry a significant risk of recurrent thromboembolism as well as postthrombotic syndrome (PTS), a complication of DVT resulting in chronic leg pain, edema, skin discoloration, and venous ulcers.⁵There is a lack of established standards of care for treating severely symptomatic or extensive proximal DVT without PCD. There are currently no specific treatment recommendations in the major guidelines for this subset of patients.

The goal of thrombolytic therapy is to prevent thrombus propagation, recurrent thromboembolism, and PTS, in addition to providing more rapid pain relief and improvement in limb function. Catheter-directed thrombolysis is preferred over systemic thrombolysis when used for DVT treatment because it is associated with less major bleeding complications and noninferior clinical outcomes.⁶ Catheter-directed thrombolysis is a minimally invasive endovascular treatment using a wire catheter combination to traverse the thrombus under fluoroscopic guidance through which a thrombolytic drug is infused over a specified duration (usually 24 to 72 hours).⁷

Catheter-directed thrombolysis can be combined with catheter-directed thrombectomy using the same endovascular technique. This combination is called a pharmacomechanical thrombectomy or a pharmacomechanical thromobolysis and can offer more rapid removal of thrombus and decreased infusion times of thrombolytic drug.⁸ Pharmacomechanical thrombolysis is a relatively new technique, so the choice of thrombolytic therapy will depend on procedural expertise and resource availability. Early interventional radiology consultation (or vascular surgery in some centers) can assist in determining appropriate candidates for thrombolytic therapies. Here we present 2 cases of extensive symptomatic DVT successfully treated with catheter-directed pharmacomechanical thrombolysis.

Case 1

A 61-year-old male current smoker with a history of obesity and hypertension presented to the West Los Angeles Veterans Affairs Medical Center emergency department (ED) with 2 days of progressive pain and swelling in the right lower extremity (RLE) after sustaining a calf injury the preceding week. The patient rated pain as 9 on a 10-point scale and reported no other symptoms. He reported no prior history of venous thromboembolism (VTE) or family history of thrombophilia.

A physical examination was notable for stable vital signs and normal cardiopulmonary examination. There was extensive RLE edema below the knee with tenderness to palpation and shiny taut skin. The neurovascular examination of the RLE was normal. Laboratory studies were notable only for a mild leukocytosis. Compression ultrasound with Doppler of the RLE demonstrated an acute thrombus of the right femoral vein extending to the popliteal vein.

The patient was prescribed enoxaparin 90 mg every 12 hours for anticoagulation. After 36 hours of anticoagulation, he continued to experience severe RLE pain and swelling limiting ambulation. Interventional radiology was consulted, and catheter-directed pharmacomechanical thrombolysis of the RLE was pursued given the persistence of significant symptoms. Intraprocedure venogram demonstrated thrombi filling the entirety of the right femoral and popliteal veins (Figure 1A). This was treated with catheter-directed pulse-spray thrombolysis with 12 mg of tissue plasminogen activator (tPA).

Case 2

A male aged 78 years with a history of hypertension, hyperlipidemia, and benign prostatic hypertrophy presented to the ED with 10 days of progressive pain and swelling in the left lower extremity (LLE). The patient noted decreased mobility over recent months and was using a front wheel walker while recovering from surgical repair of a hamstring tendon injury. He reported taking a transcontinental flight around the same time that his LLE pain began. The patient reported no prior history of VTE or family history of thrombophilia.

A physical examination was notable for stable vital signs with a normal cardiopulmonary examination. There was extensive LLE edema up to the proximal thigh without erythema or cyanosis, and his skin was taut and tender. Neurovascular examination of the LLE was normal. Laboratory studies were unremarkable. Compression ultrasonography with Doppler of the LLE demonstrated an extensive acute occlusive thrombus within the left common femoral, entire left femoral, and left popliteal veins.

After evaluating the patient, the Vascular Surgery service did not feel there was evidence of compartment syndrome nor PCD. The patient received unfractionated heparin anticoagulation therapy and the LLE was elevated continuously. After 24 hours of anticoagulation therapy, the patient continued to have significant pain and was unable to ambulate. The case was presented in a joint Interventional Radiology/Vascular Surgery conference and the decision was made to pursue pharmacomechanic thrombolysis given the significant extent of thrombotic burden.

Discussion

Anticoagulation is the preferred therapy for most patients with acute uncomplicated lower extremity DVT. PCD is the only widely accepted indication for thrombolytic therapy in patients with acute lower extremity DVT. However, in the absence of PCD, management of complicated DVT where there are either significant symptoms, extensive clot burden, or proximal location is less clear due to the paucity of clinical data. For example, in the case of iliofemoral DVT, thrombosis of the iliofemoral region is associated with an increased risk of pulmonary embolism, limb malperfusion, and PTS when compared with other types of DVT.^5,6Furthermore, despite the use of anticoagulant therapy, PTS develops within 2 years in about half of patients with proximal DVT, which can progress to major disability and impaired quality of life.⁹

Earlier retrospective observational studies in patients with acute DVT found that the addition of either systemic thrombolysis or catheter-directed thrombolysis to anticoagulation increased rates of clot lysis but did not lead to a reduction in clinical outcomes such as recurrent thromboembolism, mortality, or the rate of PTS.^10-12 Additionally, both systemic thrombolytic therapy and catheter-directed thrombolytic therapy were associated with higher rates of major bleeding. However, these studies included all patients with acute DVT without selecting for criteria, such as proximal location of DVT, severe symptoms, or extensive clot burden. Because thrombolytic therapy is proven to provide more rapid and immediate clot lysis (whereas conventional anticoagulation prevents thrombus extension and recurrence but does not dissolve the clot), it is reasonable to suggest that a subpopulation of patients with extensive or symptomatic DVT may benefit from immediate clot lysis, thereby restoring limb perfusion and avoiding limb gangrene while preserving venous function and preventing PTS.

Mixed Study Results

The 2012 CaVenT study is one of the few randomized controlled trials to assess outcomes comparing conventional anticoagulation alone to anticoagulation with catheter-directed thrombolysis in patients with acute lower extremity DVT.¹³ Study patients did not undergo catheter-directed mechanical thrombectomy. Patients in this study consisted solely of those with first-time iliofemoral DVT. Long-term outcomes at 24-month follow-up showed that additional catheter-directed thrombolysis reduced the risk of PTS when compared with those who were treated with anticoagulation alone (41.1% vs 55.6%, P = .047). The difference in PTS corresponded to an absolute risk reduction of 14.4% (95% CI, 0.2-27.9), and the number needed to treat was 7 (95% CI, 4-502). There was a clinically relevant bleeding complication rate of 8.9% in the thrombolysis group with none leading to a permanently impaired outcome.

These results could not be confirmed by a more recent randomized control trial in 2017 conducted by Vedantham and colleagues.¹⁴ In this trial, patients with acute proximal DVT (femoral and iliofemoral DVT) were randomized to receive either anticoagulation alone or anticoagulation plus pharmacomechanical thrombolysis. In the pharmacomechanic thrombolysis group, the overall incidence of PTS and recurrent VTE was not reduced over the 24-month follow-up period. Those who developed PTS in the pharmacomechanical thrombolysis group had lower severity scores, as there was a significant reduction in moderate-to-severe PTS in this group. There also were more early major bleeds in the pharmacomechanic thrombolysis group (1.7%, with no fatal or intracranial bleeds) when compared with the control group; however, this bleeding complication rate was much less than what was noted in the CaVenT study. Additionally, there was a significant decrease in both lower extremity pain and edema in the pharmacomechanical thrombolysis group at 10 days and 30 days postintervention.

Given the mixed results of these 2 randomized controlled trials, further studies are warranted to clarify the role of thrombolytic therapies in preventing major events such as recurrent VTE and PTS, especially given the increased risk of bleeding observed with thrombolytic therapies. The 2016 American College of Chest Physicians guidelines recommend anticoagulation as monotherapy vs thrombolytics, systemic or catheter-directed thrombolysis as designated treatment modalities.³ These guidelines are rated “Grade 2C”, which reflect a weak recommendation based on low-quality evidence. While these recommendations do not comment on additional considerations, such as DVT clot burden, location, or severity of symptoms, the guidelines do state that patients who attach a high value to the prevention of PTS and a lower value to the risk of bleeding with catheter-directed therapy are likely to choose catheter-directed therapy over anticoagulation alone.

Case Studies Analyses

In our first case presentation, pharma-comechanic thrombolysis was pursued because the patient presented with severesymptoms and did not experience any symptomatic improvement after 36 hours of anticoagulation. It is unclear whether a longer duration of anticoagulation might have improved the severity of his symptoms. When considering the level of pain, edema, and inability to ambulate, thrombolytic therapy was considered the most appropriate choice for treatment. Pharmacomechanic thrombolysis was successful, resulting in complete clot lysis, significant decrease in pain and edema with total recovery of ambulatory abilities, no bleeding complications, and prevention of any potential clinical deterioration, such as phlegmasia cerulea dolens. The patient is now 12 months postprocedure without symptoms of PTS or recurrent thromboembolic events. Continued follow-up that monitors the development of PTS will be necessary for at least 2 years postprocedure.

In the second case, our patient experienced some improvement in pain after 24 hours of anticoagulation alone. However, considering the extensive proximal clot burden involving the entire femoral and common femoral veins, the treatment teams believed it was likely that this patient would experience a prolonged recovery time and increased morbidity on anticoagulant therapy alone. Pharmacomechanic thrombolysis was again successful with almost immediate resolution of pain and edema, and recovery of ambulatory abilities on postprocedure day 1. The patient is now 6 months postprocedure without any symptoms of PTS or recurrent thromboembolic events.

In both case presentations, the presenting symptoms, methods of treatment, and immediate symptomatic improvement postintervention were similar. The patient in Case 2 had more extensive clot burden, a more proximal location of clot, and was classified as having an iliofemoral DVT because the thrombus included the common femoral vein; the decision for intervention in this case was more weighted on clot burden and location rather than on the significant symptoms of severe pain and difficulty with ambulation seen in Case 1. However, it is noteworthy that in Case 2 our patient also experienced significant improvement in pain, swelling, and ambulation postintervention. Complications were minimal and limited to Case 2 where our patient experienced mild asymptomatic hematuria likely related to the catheter-directed tPA that resolved spontaneously within hours and did not cause further complications. Additionally, it is likely that the length of hospital stay was decreased significantly in both cases given the rapid improvement in symptoms and recovery of ambulatory abilities.

High-Risk Patients

Given the successful treatment results in these 2 cases, we believe that there is a subset of higher-risk patients with severe symptomatic proximal DVT but without PCD that may benefit from the addition of thrombolytic therapies to anticoagulation. These patients may present with significant pain, difficulty ambulating, and will likely have extensive proximal clot burden. Immediate thrombolytic intervention can achieve rapid symptom relief, which, in turn, can decrease morbidity by decreasing length of hospitalization, improving ambulation, and possibly decreasing the incidence or severity of future PTS. Positive outcomes may be easier to predict for those with obvious features of pain, edema, and difficulty ambulating, which may be more readily reversed by rapid clot reversal/removal.

These patients should be considered on a case-by-case basis. For example, the severity of pain can be balanced against the patient’s risk factors for bleeding because rapid thrombus lysis or immediate thrombus removal will likely reduce the pain. Patients who attach a high value to functional quality (eg, both patients in this case study experienced significant difficulty ambulating), quicker recovery, and decreased hospitalization duration may be more likely to choose the addition of thrombolytic therapies over anticoagulation alone and accept the higher risk of bleed. A scoring system with inclusion/exclusion criteria such as location of clot, bleeding history, age, and pain can create an individualized approach for each patient. Future studies also could consider using a detailed pretreatment symptom-severity score (similar to the Likert pain scale and calf circumference measurements used by Vedantham and colleagues¹⁴) and assess whether higher symptom-severity patients are more likely to benefit from the addition of thrombolytic therapies to anticoagulation. Positive outcomes can be assessed for the short-term such as pain severity, ability to ambulate, and length of hospitalization. Additionally, it would be important to determine whether there is a correlation with severity of pain on presentation and future PTS incidence or severity—a positive correlation would lend further support toward using thrombolytic therapies in those with severe symptomatic DVT.

Finally, additional studies involving variations in methodology should be examined, including whether pharmacomechanic thrombolysis may be safer in terms of bleeding than catheter-directed thrombolysis alone, as suggested by the lower bleeding rates seen in the pharmacomechanic study by Vedantham and colleagues when compared with the CaVenT study.^13,14 Patients in the CaVenT study received an infusion of 20 mg of alteplase over a maximum of 96 hours. Patients in the pharmacomechanic study by Vedanthem and colleagues received either a rapid pulsed delivery of alteplase over a single procedural session (as in our 2 cases) or a maximum of 30 hours of alteplase infusion (total alteplase dose < 35 mg) followed by thrombus removal. It is possible that the lower incidence of major bleeds observed in the study by Vedanthem and colleagues is a result of the decreased exposure to thrombolytic agents.

Conclusions

There is a relative lack of high-quality data examining thrombolytic therapies in the setting of acute lower extremity DVT. Recent studies have prioritized evaluation of the posttreatment incidence of PTS, recurrent thromboembolism, and risk of bleeding caused by thrombolytic therapies. Results are mixed thus far, and further studies are necessary to clarify a more definitive role for thrombolytic therapies, particularly in established higher-risk populations with proximal DVT. In this case series, we highlighted 2 patients with extensive proximal DVT burden with significant symptoms who experienced almost complete resolution of symptoms immediately following thrombolytic therapies. We postulate that even in the absence of PCD, there is a subset of patients with severe symptoms in the setting of acute proximal lower extremity DVT that clearly benefit from thrombolytic therapies.

Deep vein thrombosis (DVT) is a frequently encountered medical condition with about 1 in 1,000 adults diagnosed annually.^1,2 Up to one-half of patients who receive a diagnosis will experience long-term complications in the affected limb.¹ Anticoagulation is the treatment of choice for DVT in the absence of any contraindications.³ Thrombolytic therapies (eg, systemic thrombolysis, catheter-directed thrombolysis with or without thrombectomy) historically have been reserved for patients who present with phlegmasia cerulea dolens (PCD), a severe condition involving venous obstruction within the extremities that causes impaired arterial blood supply and cyanosis that can lead to limb loss and death.⁴

The role of thrombolytic therapy is less clear in patients without PCD who present with extensive or symptomatic lower extremity DVT that causes significant pain, edema, and functional disability. Proximal lower extremity DVT (thrombus above the knee and above the popliteal vein) and particularly those involving the iliac or common femoral vein (ie, iliofemoral DVT) carry a significant risk of recurrent thromboembolism as well as postthrombotic syndrome (PTS), a complication of DVT resulting in chronic leg pain, edema, skin discoloration, and venous ulcers.⁵There is a lack of established standards of care for treating severely symptomatic or extensive proximal DVT without PCD. There are currently no specific treatment recommendations in the major guidelines for this subset of patients.

The goal of thrombolytic therapy is to prevent thrombus propagation, recurrent thromboembolism, and PTS, in addition to providing more rapid pain relief and improvement in limb function. Catheter-directed thrombolysis is preferred over systemic thrombolysis when used for DVT treatment because it is associated with less major bleeding complications and noninferior clinical outcomes.⁶ Catheter-directed thrombolysis is a minimally invasive endovascular treatment using a wire catheter combination to traverse the thrombus under fluoroscopic guidance through which a thrombolytic drug is infused over a specified duration (usually 24 to 72 hours).⁷

Catheter-directed thrombolysis can be combined with catheter-directed thrombectomy using the same endovascular technique. This combination is called a pharmacomechanical thrombectomy or a pharmacomechanical thromobolysis and can offer more rapid removal of thrombus and decreased infusion times of thrombolytic drug.⁸ Pharmacomechanical thrombolysis is a relatively new technique, so the choice of thrombolytic therapy will depend on procedural expertise and resource availability. Early interventional radiology consultation (or vascular surgery in some centers) can assist in determining appropriate candidates for thrombolytic therapies. Here we present 2 cases of extensive symptomatic DVT successfully treated with catheter-directed pharmacomechanical thrombolysis.

Case 1

A 61-year-old male current smoker with a history of obesity and hypertension presented to the West Los Angeles Veterans Affairs Medical Center emergency department (ED) with 2 days of progressive pain and swelling in the right lower extremity (RLE) after sustaining a calf injury the preceding week. The patient rated pain as 9 on a 10-point scale and reported no other symptoms. He reported no prior history of venous thromboembolism (VTE) or family history of thrombophilia.

A physical examination was notable for stable vital signs and normal cardiopulmonary examination. There was extensive RLE edema below the knee with tenderness to palpation and shiny taut skin. The neurovascular examination of the RLE was normal. Laboratory studies were notable only for a mild leukocytosis. Compression ultrasound with Doppler of the RLE demonstrated an acute thrombus of the right femoral vein extending to the popliteal vein.

The patient was prescribed enoxaparin 90 mg every 12 hours for anticoagulation. After 36 hours of anticoagulation, he continued to experience severe RLE pain and swelling limiting ambulation. Interventional radiology was consulted, and catheter-directed pharmacomechanical thrombolysis of the RLE was pursued given the persistence of significant symptoms. Intraprocedure venogram demonstrated thrombi filling the entirety of the right femoral and popliteal veins (Figure 1A). This was treated with catheter-directed pulse-spray thrombolysis with 12 mg of tissue plasminogen activator (tPA).

Case 2

A male aged 78 years with a history of hypertension, hyperlipidemia, and benign prostatic hypertrophy presented to the ED with 10 days of progressive pain and swelling in the left lower extremity (LLE). The patient noted decreased mobility over recent months and was using a front wheel walker while recovering from surgical repair of a hamstring tendon injury. He reported taking a transcontinental flight around the same time that his LLE pain began. The patient reported no prior history of VTE or family history of thrombophilia.

A physical examination was notable for stable vital signs with a normal cardiopulmonary examination. There was extensive LLE edema up to the proximal thigh without erythema or cyanosis, and his skin was taut and tender. Neurovascular examination of the LLE was normal. Laboratory studies were unremarkable. Compression ultrasonography with Doppler of the LLE demonstrated an extensive acute occlusive thrombus within the left common femoral, entire left femoral, and left popliteal veins.

After evaluating the patient, the Vascular Surgery service did not feel there was evidence of compartment syndrome nor PCD. The patient received unfractionated heparin anticoagulation therapy and the LLE was elevated continuously. After 24 hours of anticoagulation therapy, the patient continued to have significant pain and was unable to ambulate. The case was presented in a joint Interventional Radiology/Vascular Surgery conference and the decision was made to pursue pharmacomechanic thrombolysis given the significant extent of thrombotic burden.

Discussion

Anticoagulation is the preferred therapy for most patients with acute uncomplicated lower extremity DVT. PCD is the only widely accepted indication for thrombolytic therapy in patients with acute lower extremity DVT. However, in the absence of PCD, management of complicated DVT where there are either significant symptoms, extensive clot burden, or proximal location is less clear due to the paucity of clinical data. For example, in the case of iliofemoral DVT, thrombosis of the iliofemoral region is associated with an increased risk of pulmonary embolism, limb malperfusion, and PTS when compared with other types of DVT.^5,6Furthermore, despite the use of anticoagulant therapy, PTS develops within 2 years in about half of patients with proximal DVT, which can progress to major disability and impaired quality of life.⁹

Earlier retrospective observational studies in patients with acute DVT found that the addition of either systemic thrombolysis or catheter-directed thrombolysis to anticoagulation increased rates of clot lysis but did not lead to a reduction in clinical outcomes such as recurrent thromboembolism, mortality, or the rate of PTS.^10-12 Additionally, both systemic thrombolytic therapy and catheter-directed thrombolytic therapy were associated with higher rates of major bleeding. However, these studies included all patients with acute DVT without selecting for criteria, such as proximal location of DVT, severe symptoms, or extensive clot burden. Because thrombolytic therapy is proven to provide more rapid and immediate clot lysis (whereas conventional anticoagulation prevents thrombus extension and recurrence but does not dissolve the clot), it is reasonable to suggest that a subpopulation of patients with extensive or symptomatic DVT may benefit from immediate clot lysis, thereby restoring limb perfusion and avoiding limb gangrene while preserving venous function and preventing PTS.

Mixed Study Results

The 2012 CaVenT study is one of the few randomized controlled trials to assess outcomes comparing conventional anticoagulation alone to anticoagulation with catheter-directed thrombolysis in patients with acute lower extremity DVT.¹³ Study patients did not undergo catheter-directed mechanical thrombectomy. Patients in this study consisted solely of those with first-time iliofemoral DVT. Long-term outcomes at 24-month follow-up showed that additional catheter-directed thrombolysis reduced the risk of PTS when compared with those who were treated with anticoagulation alone (41.1% vs 55.6%, P = .047). The difference in PTS corresponded to an absolute risk reduction of 14.4% (95% CI, 0.2-27.9), and the number needed to treat was 7 (95% CI, 4-502). There was a clinically relevant bleeding complication rate of 8.9% in the thrombolysis group with none leading to a permanently impaired outcome.

These results could not be confirmed by a more recent randomized control trial in 2017 conducted by Vedantham and colleagues.¹⁴ In this trial, patients with acute proximal DVT (femoral and iliofemoral DVT) were randomized to receive either anticoagulation alone or anticoagulation plus pharmacomechanical thrombolysis. In the pharmacomechanic thrombolysis group, the overall incidence of PTS and recurrent VTE was not reduced over the 24-month follow-up period. Those who developed PTS in the pharmacomechanical thrombolysis group had lower severity scores, as there was a significant reduction in moderate-to-severe PTS in this group. There also were more early major bleeds in the pharmacomechanic thrombolysis group (1.7%, with no fatal or intracranial bleeds) when compared with the control group; however, this bleeding complication rate was much less than what was noted in the CaVenT study. Additionally, there was a significant decrease in both lower extremity pain and edema in the pharmacomechanical thrombolysis group at 10 days and 30 days postintervention.

Given the mixed results of these 2 randomized controlled trials, further studies are warranted to clarify the role of thrombolytic therapies in preventing major events such as recurrent VTE and PTS, especially given the increased risk of bleeding observed with thrombolytic therapies. The 2016 American College of Chest Physicians guidelines recommend anticoagulation as monotherapy vs thrombolytics, systemic or catheter-directed thrombolysis as designated treatment modalities.³ These guidelines are rated “Grade 2C”, which reflect a weak recommendation based on low-quality evidence. While these recommendations do not comment on additional considerations, such as DVT clot burden, location, or severity of symptoms, the guidelines do state that patients who attach a high value to the prevention of PTS and a lower value to the risk of bleeding with catheter-directed therapy are likely to choose catheter-directed therapy over anticoagulation alone.

Case Studies Analyses

In our first case presentation, pharma-comechanic thrombolysis was pursued because the patient presented with severesymptoms and did not experience any symptomatic improvement after 36 hours of anticoagulation. It is unclear whether a longer duration of anticoagulation might have improved the severity of his symptoms. When considering the level of pain, edema, and inability to ambulate, thrombolytic therapy was considered the most appropriate choice for treatment. Pharmacomechanic thrombolysis was successful, resulting in complete clot lysis, significant decrease in pain and edema with total recovery of ambulatory abilities, no bleeding complications, and prevention of any potential clinical deterioration, such as phlegmasia cerulea dolens. The patient is now 12 months postprocedure without symptoms of PTS or recurrent thromboembolic events. Continued follow-up that monitors the development of PTS will be necessary for at least 2 years postprocedure.

In the second case, our patient experienced some improvement in pain after 24 hours of anticoagulation alone. However, considering the extensive proximal clot burden involving the entire femoral and common femoral veins, the treatment teams believed it was likely that this patient would experience a prolonged recovery time and increased morbidity on anticoagulant therapy alone. Pharmacomechanic thrombolysis was again successful with almost immediate resolution of pain and edema, and recovery of ambulatory abilities on postprocedure day 1. The patient is now 6 months postprocedure without any symptoms of PTS or recurrent thromboembolic events.

In both case presentations, the presenting symptoms, methods of treatment, and immediate symptomatic improvement postintervention were similar. The patient in Case 2 had more extensive clot burden, a more proximal location of clot, and was classified as having an iliofemoral DVT because the thrombus included the common femoral vein; the decision for intervention in this case was more weighted on clot burden and location rather than on the significant symptoms of severe pain and difficulty with ambulation seen in Case 1. However, it is noteworthy that in Case 2 our patient also experienced significant improvement in pain, swelling, and ambulation postintervention. Complications were minimal and limited to Case 2 where our patient experienced mild asymptomatic hematuria likely related to the catheter-directed tPA that resolved spontaneously within hours and did not cause further complications. Additionally, it is likely that the length of hospital stay was decreased significantly in both cases given the rapid improvement in symptoms and recovery of ambulatory abilities.

High-Risk Patients

Given the successful treatment results in these 2 cases, we believe that there is a subset of higher-risk patients with severe symptomatic proximal DVT but without PCD that may benefit from the addition of thrombolytic therapies to anticoagulation. These patients may present with significant pain, difficulty ambulating, and will likely have extensive proximal clot burden. Immediate thrombolytic intervention can achieve rapid symptom relief, which, in turn, can decrease morbidity by decreasing length of hospitalization, improving ambulation, and possibly decreasing the incidence or severity of future PTS. Positive outcomes may be easier to predict for those with obvious features of pain, edema, and difficulty ambulating, which may be more readily reversed by rapid clot reversal/removal.

These patients should be considered on a case-by-case basis. For example, the severity of pain can be balanced against the patient’s risk factors for bleeding because rapid thrombus lysis or immediate thrombus removal will likely reduce the pain. Patients who attach a high value to functional quality (eg, both patients in this case study experienced significant difficulty ambulating), quicker recovery, and decreased hospitalization duration may be more likely to choose the addition of thrombolytic therapies over anticoagulation alone and accept the higher risk of bleed. A scoring system with inclusion/exclusion criteria such as location of clot, bleeding history, age, and pain can create an individualized approach for each patient. Future studies also could consider using a detailed pretreatment symptom-severity score (similar to the Likert pain scale and calf circumference measurements used by Vedantham and colleagues¹⁴) and assess whether higher symptom-severity patients are more likely to benefit from the addition of thrombolytic therapies to anticoagulation. Positive outcomes can be assessed for the short-term such as pain severity, ability to ambulate, and length of hospitalization. Additionally, it would be important to determine whether there is a correlation with severity of pain on presentation and future PTS incidence or severity—a positive correlation would lend further support toward using thrombolytic therapies in those with severe symptomatic DVT.

Finally, additional studies involving variations in methodology should be examined, including whether pharmacomechanic thrombolysis may be safer in terms of bleeding than catheter-directed thrombolysis alone, as suggested by the lower bleeding rates seen in the pharmacomechanic study by Vedantham and colleagues when compared with the CaVenT study.^13,14 Patients in the CaVenT study received an infusion of 20 mg of alteplase over a maximum of 96 hours. Patients in the pharmacomechanic study by Vedanthem and colleagues received either a rapid pulsed delivery of alteplase over a single procedural session (as in our 2 cases) or a maximum of 30 hours of alteplase infusion (total alteplase dose < 35 mg) followed by thrombus removal. It is possible that the lower incidence of major bleeds observed in the study by Vedanthem and colleagues is a result of the decreased exposure to thrombolytic agents.

Conclusions

There is a relative lack of high-quality data examining thrombolytic therapies in the setting of acute lower extremity DVT. Recent studies have prioritized evaluation of the posttreatment incidence of PTS, recurrent thromboembolism, and risk of bleeding caused by thrombolytic therapies. Results are mixed thus far, and further studies are necessary to clarify a more definitive role for thrombolytic therapies, particularly in established higher-risk populations with proximal DVT. In this case series, we highlighted 2 patients with extensive proximal DVT burden with significant symptoms who experienced almost complete resolution of symptoms immediately following thrombolytic therapies. We postulate that even in the absence of PCD, there is a subset of patients with severe symptoms in the setting of acute proximal lower extremity DVT that clearly benefit from thrombolytic therapies.

Deep vein thrombosis (DVT) is a frequently encountered medical condition with about 1 in 1,000 adults diagnosed annually.^1,2 Up to one-half of patients who receive a diagnosis will experience long-term complications in the affected limb.¹ Anticoagulation is the treatment of choice for DVT in the absence of any contraindications.³ Thrombolytic therapies (eg, systemic thrombolysis, catheter-directed thrombolysis with or without thrombectomy) historically have been reserved for patients who present with phlegmasia cerulea dolens (PCD), a severe condition involving venous obstruction within the extremities that causes impaired arterial blood supply and cyanosis that can lead to limb loss and death.⁴

The role of thrombolytic therapy is less clear in patients without PCD who present with extensive or symptomatic lower extremity DVT that causes significant pain, edema, and functional disability. Proximal lower extremity DVT (thrombus above the knee and above the popliteal vein) and particularly those involving the iliac or common femoral vein (ie, iliofemoral DVT) carry a significant risk of recurrent thromboembolism as well as postthrombotic syndrome (PTS), a complication of DVT resulting in chronic leg pain, edema, skin discoloration, and venous ulcers.⁵There is a lack of established standards of care for treating severely symptomatic or extensive proximal DVT without PCD. There are currently no specific treatment recommendations in the major guidelines for this subset of patients.

The goal of thrombolytic therapy is to prevent thrombus propagation, recurrent thromboembolism, and PTS, in addition to providing more rapid pain relief and improvement in limb function. Catheter-directed thrombolysis is preferred over systemic thrombolysis when used for DVT treatment because it is associated with less major bleeding complications and noninferior clinical outcomes.⁶ Catheter-directed thrombolysis is a minimally invasive endovascular treatment using a wire catheter combination to traverse the thrombus under fluoroscopic guidance through which a thrombolytic drug is infused over a specified duration (usually 24 to 72 hours).⁷

Catheter-directed thrombolysis can be combined with catheter-directed thrombectomy using the same endovascular technique. This combination is called a pharmacomechanical thrombectomy or a pharmacomechanical thromobolysis and can offer more rapid removal of thrombus and decreased infusion times of thrombolytic drug.⁸ Pharmacomechanical thrombolysis is a relatively new technique, so the choice of thrombolytic therapy will depend on procedural expertise and resource availability. Early interventional radiology consultation (or vascular surgery in some centers) can assist in determining appropriate candidates for thrombolytic therapies. Here we present 2 cases of extensive symptomatic DVT successfully treated with catheter-directed pharmacomechanical thrombolysis.

Case 1

A 61-year-old male current smoker with a history of obesity and hypertension presented to the West Los Angeles Veterans Affairs Medical Center emergency department (ED) with 2 days of progressive pain and swelling in the right lower extremity (RLE) after sustaining a calf injury the preceding week. The patient rated pain as 9 on a 10-point scale and reported no other symptoms. He reported no prior history of venous thromboembolism (VTE) or family history of thrombophilia.

A physical examination was notable for stable vital signs and normal cardiopulmonary examination. There was extensive RLE edema below the knee with tenderness to palpation and shiny taut skin. The neurovascular examination of the RLE was normal. Laboratory studies were notable only for a mild leukocytosis. Compression ultrasound with Doppler of the RLE demonstrated an acute thrombus of the right femoral vein extending to the popliteal vein.

The patient was prescribed enoxaparin 90 mg every 12 hours for anticoagulation. After 36 hours of anticoagulation, he continued to experience severe RLE pain and swelling limiting ambulation. Interventional radiology was consulted, and catheter-directed pharmacomechanical thrombolysis of the RLE was pursued given the persistence of significant symptoms. Intraprocedure venogram demonstrated thrombi filling the entirety of the right femoral and popliteal veins (Figure 1A). This was treated with catheter-directed pulse-spray thrombolysis with 12 mg of tissue plasminogen activator (tPA).

Case 2

A male aged 78 years with a history of hypertension, hyperlipidemia, and benign prostatic hypertrophy presented to the ED with 10 days of progressive pain and swelling in the left lower extremity (LLE). The patient noted decreased mobility over recent months and was using a front wheel walker while recovering from surgical repair of a hamstring tendon injury. He reported taking a transcontinental flight around the same time that his LLE pain began. The patient reported no prior history of VTE or family history of thrombophilia.

A physical examination was notable for stable vital signs with a normal cardiopulmonary examination. There was extensive LLE edema up to the proximal thigh without erythema or cyanosis, and his skin was taut and tender. Neurovascular examination of the LLE was normal. Laboratory studies were unremarkable. Compression ultrasonography with Doppler of the LLE demonstrated an extensive acute occlusive thrombus within the left common femoral, entire left femoral, and left popliteal veins.

After evaluating the patient, the Vascular Surgery service did not feel there was evidence of compartment syndrome nor PCD. The patient received unfractionated heparin anticoagulation therapy and the LLE was elevated continuously. After 24 hours of anticoagulation therapy, the patient continued to have significant pain and was unable to ambulate. The case was presented in a joint Interventional Radiology/Vascular Surgery conference and the decision was made to pursue pharmacomechanic thrombolysis given the significant extent of thrombotic burden.

Discussion

Anticoagulation is the preferred therapy for most patients with acute uncomplicated lower extremity DVT. PCD is the only widely accepted indication for thrombolytic therapy in patients with acute lower extremity DVT. However, in the absence of PCD, management of complicated DVT where there are either significant symptoms, extensive clot burden, or proximal location is less clear due to the paucity of clinical data. For example, in the case of iliofemoral DVT, thrombosis of the iliofemoral region is associated with an increased risk of pulmonary embolism, limb malperfusion, and PTS when compared with other types of DVT.^5,6Furthermore, despite the use of anticoagulant therapy, PTS develops within 2 years in about half of patients with proximal DVT, which can progress to major disability and impaired quality of life.⁹

Earlier retrospective observational studies in patients with acute DVT found that the addition of either systemic thrombolysis or catheter-directed thrombolysis to anticoagulation increased rates of clot lysis but did not lead to a reduction in clinical outcomes such as recurrent thromboembolism, mortality, or the rate of PTS.^10-12 Additionally, both systemic thrombolytic therapy and catheter-directed thrombolytic therapy were associated with higher rates of major bleeding. However, these studies included all patients with acute DVT without selecting for criteria, such as proximal location of DVT, severe symptoms, or extensive clot burden. Because thrombolytic therapy is proven to provide more rapid and immediate clot lysis (whereas conventional anticoagulation prevents thrombus extension and recurrence but does not dissolve the clot), it is reasonable to suggest that a subpopulation of patients with extensive or symptomatic DVT may benefit from immediate clot lysis, thereby restoring limb perfusion and avoiding limb gangrene while preserving venous function and preventing PTS.

Mixed Study Results

The 2012 CaVenT study is one of the few randomized controlled trials to assess outcomes comparing conventional anticoagulation alone to anticoagulation with catheter-directed thrombolysis in patients with acute lower extremity DVT.¹³ Study patients did not undergo catheter-directed mechanical thrombectomy. Patients in this study consisted solely of those with first-time iliofemoral DVT. Long-term outcomes at 24-month follow-up showed that additional catheter-directed thrombolysis reduced the risk of PTS when compared with those who were treated with anticoagulation alone (41.1% vs 55.6%, P = .047). The difference in PTS corresponded to an absolute risk reduction of 14.4% (95% CI, 0.2-27.9), and the number needed to treat was 7 (95% CI, 4-502). There was a clinically relevant bleeding complication rate of 8.9% in the thrombolysis group with none leading to a permanently impaired outcome.

These results could not be confirmed by a more recent randomized control trial in 2017 conducted by Vedantham and colleagues.¹⁴ In this trial, patients with acute proximal DVT (femoral and iliofemoral DVT) were randomized to receive either anticoagulation alone or anticoagulation plus pharmacomechanical thrombolysis. In the pharmacomechanic thrombolysis group, the overall incidence of PTS and recurrent VTE was not reduced over the 24-month follow-up period. Those who developed PTS in the pharmacomechanical thrombolysis group had lower severity scores, as there was a significant reduction in moderate-to-severe PTS in this group. There also were more early major bleeds in the pharmacomechanic thrombolysis group (1.7%, with no fatal or intracranial bleeds) when compared with the control group; however, this bleeding complication rate was much less than what was noted in the CaVenT study. Additionally, there was a significant decrease in both lower extremity pain and edema in the pharmacomechanical thrombolysis group at 10 days and 30 days postintervention.

Given the mixed results of these 2 randomized controlled trials, further studies are warranted to clarify the role of thrombolytic therapies in preventing major events such as recurrent VTE and PTS, especially given the increased risk of bleeding observed with thrombolytic therapies. The 2016 American College of Chest Physicians guidelines recommend anticoagulation as monotherapy vs thrombolytics, systemic or catheter-directed thrombolysis as designated treatment modalities.³ These guidelines are rated “Grade 2C”, which reflect a weak recommendation based on low-quality evidence. While these recommendations do not comment on additional considerations, such as DVT clot burden, location, or severity of symptoms, the guidelines do state that patients who attach a high value to the prevention of PTS and a lower value to the risk of bleeding with catheter-directed therapy are likely to choose catheter-directed therapy over anticoagulation alone.

Case Studies Analyses

In our first case presentation, pharma-comechanic thrombolysis was pursued because the patient presented with severesymptoms and did not experience any symptomatic improvement after 36 hours of anticoagulation. It is unclear whether a longer duration of anticoagulation might have improved the severity of his symptoms. When considering the level of pain, edema, and inability to ambulate, thrombolytic therapy was considered the most appropriate choice for treatment. Pharmacomechanic thrombolysis was successful, resulting in complete clot lysis, significant decrease in pain and edema with total recovery of ambulatory abilities, no bleeding complications, and prevention of any potential clinical deterioration, such as phlegmasia cerulea dolens. The patient is now 12 months postprocedure without symptoms of PTS or recurrent thromboembolic events. Continued follow-up that monitors the development of PTS will be necessary for at least 2 years postprocedure.

In the second case, our patient experienced some improvement in pain after 24 hours of anticoagulation alone. However, considering the extensive proximal clot burden involving the entire femoral and common femoral veins, the treatment teams believed it was likely that this patient would experience a prolonged recovery time and increased morbidity on anticoagulant therapy alone. Pharmacomechanic thrombolysis was again successful with almost immediate resolution of pain and edema, and recovery of ambulatory abilities on postprocedure day 1. The patient is now 6 months postprocedure without any symptoms of PTS or recurrent thromboembolic events.

In both case presentations, the presenting symptoms, methods of treatment, and immediate symptomatic improvement postintervention were similar. The patient in Case 2 had more extensive clot burden, a more proximal location of clot, and was classified as having an iliofemoral DVT because the thrombus included the common femoral vein; the decision for intervention in this case was more weighted on clot burden and location rather than on the significant symptoms of severe pain and difficulty with ambulation seen in Case 1. However, it is noteworthy that in Case 2 our patient also experienced significant improvement in pain, swelling, and ambulation postintervention. Complications were minimal and limited to Case 2 where our patient experienced mild asymptomatic hematuria likely related to the catheter-directed tPA that resolved spontaneously within hours and did not cause further complications. Additionally, it is likely that the length of hospital stay was decreased significantly in both cases given the rapid improvement in symptoms and recovery of ambulatory abilities.

High-Risk Patients

Given the successful treatment results in these 2 cases, we believe that there is a subset of higher-risk patients with severe symptomatic proximal DVT but without PCD that may benefit from the addition of thrombolytic therapies to anticoagulation. These patients may present with significant pain, difficulty ambulating, and will likely have extensive proximal clot burden. Immediate thrombolytic intervention can achieve rapid symptom relief, which, in turn, can decrease morbidity by decreasing length of hospitalization, improving ambulation, and possibly decreasing the incidence or severity of future PTS. Positive outcomes may be easier to predict for those with obvious features of pain, edema, and difficulty ambulating, which may be more readily reversed by rapid clot reversal/removal.

These patients should be considered on a case-by-case basis. For example, the severity of pain can be balanced against the patient’s risk factors for bleeding because rapid thrombus lysis or immediate thrombus removal will likely reduce the pain. Patients who attach a high value to functional quality (eg, both patients in this case study experienced significant difficulty ambulating), quicker recovery, and decreased hospitalization duration may be more likely to choose the addition of thrombolytic therapies over anticoagulation alone and accept the higher risk of bleed. A scoring system with inclusion/exclusion criteria such as location of clot, bleeding history, age, and pain can create an individualized approach for each patient. Future studies also could consider using a detailed pretreatment symptom-severity score (similar to the Likert pain scale and calf circumference measurements used by Vedantham and colleagues¹⁴) and assess whether higher symptom-severity patients are more likely to benefit from the addition of thrombolytic therapies to anticoagulation. Positive outcomes can be assessed for the short-term such as pain severity, ability to ambulate, and length of hospitalization. Additionally, it would be important to determine whether there is a correlation with severity of pain on presentation and future PTS incidence or severity—a positive correlation would lend further support toward using thrombolytic therapies in those with severe symptomatic DVT.

Finally, additional studies involving variations in methodology should be examined, including whether pharmacomechanic thrombolysis may be safer in terms of bleeding than catheter-directed thrombolysis alone, as suggested by the lower bleeding rates seen in the pharmacomechanic study by Vedantham and colleagues when compared with the CaVenT study.^13,14 Patients in the CaVenT study received an infusion of 20 mg of alteplase over a maximum of 96 hours. Patients in the pharmacomechanic study by Vedanthem and colleagues received either a rapid pulsed delivery of alteplase over a single procedural session (as in our 2 cases) or a maximum of 30 hours of alteplase infusion (total alteplase dose < 35 mg) followed by thrombus removal. It is possible that the lower incidence of major bleeds observed in the study by Vedanthem and colleagues is a result of the decreased exposure to thrombolytic agents.

Conclusions

There is a relative lack of high-quality data examining thrombolytic therapies in the setting of acute lower extremity DVT. Recent studies have prioritized evaluation of the posttreatment incidence of PTS, recurrent thromboembolism, and risk of bleeding caused by thrombolytic therapies. Results are mixed thus far, and further studies are necessary to clarify a more definitive role for thrombolytic therapies, particularly in established higher-risk populations with proximal DVT. In this case series, we highlighted 2 patients with extensive proximal DVT burden with significant symptoms who experienced almost complete resolution of symptoms immediately following thrombolytic therapies. We postulate that even in the absence of PCD, there is a subset of patients with severe symptoms in the setting of acute proximal lower extremity DVT that clearly benefit from thrombolytic therapies.

Heparin is the anticoagulant of choice when a rapid anticoagulant is indicated: Onset of action is immediate when administered IV as a bolus.¹ The major anticoagulant effect of heparin is mediated by heparin/antithrombin (AT) interaction. Heparin/AT inactivates factor IIa (thrombin) and factors Xa, IXa, XIa, and XIIa. Heparin is approved for multiple indications, such as venous thromboembolism (VTE) treatment and prophylaxis of medical and surgical patients; stroke prevention in atrial fibrillation (AF); acute coronary syndrome (ACS); vascular and cardiac surgeries; and various interventional procedures (eg, diagnostic angiography and percutaneous coronary intervention [PCI]). It also is used as an anticoagulant in blood transfusions, extracorporeal circulation, and for maintaining patency of central vascular access devices (CVADs).

About 60% of the crude heparin used to manufacture heparin in the US originates in China, derived from porcine mucosa. African swine fever, a contagious virus with no cure, has eliminated about 25% to 35% of China’s pig population, or about 150 million pigs. In July 2019, members of the US House of Representatives Committee on Energy and Commerce sent a letter to the US Food and Drug Administration asking for details on the potential impact of African swine fever on the supply of heparin.²

The US Department of Veterans Affairs (VA) heath care system is currently experiencing a shortage of heparin vials and syringes. It is unclear when resolution of this shortage will occur as it could resolve within several weeks or as late as January 2020.³ Although vials and syringes are the current products that are affected, it is possible the shortage may eventually include IV heparin bags as well.

Since the foremost objective of VA health care providers is to provide timely access to medications for veterans, strategies to conserve unfractionated heparin (UfH) must be used since it is a first-line therapy where few evidence-based alternatives exist. Conservation strategies may include drug rationing, therapeutic substitution, and compounding of needed products using the limited stock available in the pharmacy.⁴ It is important that all staff are educated on facility strategies in order to be familiar with alternatives and limit the potential for near misses, adverse events, and provider frustration.

In shortage situations, the VA-Pharmacy Benefits Management (PBM) defers decisions regarding drug preservation, processes to shift to viable alternatives, and the best practice for safe transitions to local facilities and their subject matter experts.⁵ At the VA Tennessee Valley Healthcare System, a 1A, tertiary, dual campus health care system, a pharmacy task force has formed to track drug shortages impacting the facility’s efficiencies and budgets. This group communicates with the Pharmacy and Therapeutics committee about potential risks to patient care and develops shortage briefs (following an SBAR [situation, background, assessment, recommendation] design) generally authored and championed by at least 1 clinical pharmacy specialist and supervising physicians who are field experts. Prior to dissemination, the SBAR undergoes a rapid peer-review process.

To date, VA PBM has not issued specific guidance on how pharmacists should proceed in case of a shortage. However, we recommend strategies that may be considered for implementation during a potential UfH shortage. For example, pharmacists can use therapeutic alternatives for which best available evidence suggests no disadvantage.⁴ The Table lists alternative agents according to indication and patient-specific considerations that may preclude use. Existing UfH products may also be used for drug compounding (eg, use current stock to provide an indicated aliquot) to meet the need of prioritized patients.⁴ In addition, we suggest prioritizing current UfH/heparinized saline for use for the following groups of patients⁴:

• Emergent/urgent cardiac surgery^1,6;
• Hemodialysis patients^1,7-9 for which the low-molecular-weight heparin (LMWH) dalteparin is deemed inappropriate or the patient is not monitored in the intensive care unit for regional citrate administration;
• VTE prophylaxis for patients with epidurals or chest tubes for which urgent invasive management may occur, recent cardiac or neurosurgery, or for patients with a creatine clearance < 15 mL/min or receiving hemodialysis^10-12;
• Vascular surgery (eg, limb ischemia) and interventions (eg, carotid stenting, endarterectomy)^13,14;
• Mesenteric ischemia (venous thrombosis) with a potential to proceed to laparotomy¹⁵;
• Critically ill patients with arterial lines for which normal saline is deemed inappropriate for line flushing¹⁶;
• Electrophysiology procedures (eg, AF ablation)¹⁷; and
• Contraindication to use of a long-acting alternative listed in the table or a medical necessity exists for using a rapidly reversible agent. Examples for this category include but are not limited to recent gastrointestinal bleeding, central nervous system lesion, and select neurologic diagnoses (eg, cerebral venous sinus thrombosis with hemorrhage, thrombus in vertebral basilar system or anterior circulation, intraparenchymal hemorrhage plus mechanical valve, medium to large cardioembolic stroke with intracardiac thrombus).

Conclusion

The UfH drug shortage represents a significant threat to public health and is a major challenge for US health care systems, including the Veterans Health Administration. Overreliance on a predominant source of crude heparin has affected multiple UfH manufacturers and products. Current alternatives to UfH include low-molecular-weight heparins, IV direct thrombin inhibitors, and SC fondaparinux, with selection supported by guidelines or evolving literature. However, the shortage has the potential to expand to other injectables, such as dalteparin and enoxaparin, and severely limit care for veterans. It is vital that clinicians rapidly address the current shortage by creating a plan to develop efficient and equitable access to UfH, continue to assess supply and update stakeholders, and select evidence-based alternatives while maintaining focus on efficacy and safety.

Acknowledgments

The authors thank Ashley Yost, PharmD, for her coordination of the multidisciplinary task force assigned to efficiently manage the heparin drug shortage. This material is the result of work supported with resources and the use of facilities at the VA Tennessee Valley Healthcare System in Nashville, Tennessee.

Heparin is the anticoagulant of choice when a rapid anticoagulant is indicated: Onset of action is immediate when administered IV as a bolus.¹ The major anticoagulant effect of heparin is mediated by heparin/antithrombin (AT) interaction. Heparin/AT inactivates factor IIa (thrombin) and factors Xa, IXa, XIa, and XIIa. Heparin is approved for multiple indications, such as venous thromboembolism (VTE) treatment and prophylaxis of medical and surgical patients; stroke prevention in atrial fibrillation (AF); acute coronary syndrome (ACS); vascular and cardiac surgeries; and various interventional procedures (eg, diagnostic angiography and percutaneous coronary intervention [PCI]). It also is used as an anticoagulant in blood transfusions, extracorporeal circulation, and for maintaining patency of central vascular access devices (CVADs).

About 60% of the crude heparin used to manufacture heparin in the US originates in China, derived from porcine mucosa. African swine fever, a contagious virus with no cure, has eliminated about 25% to 35% of China’s pig population, or about 150 million pigs. In July 2019, members of the US House of Representatives Committee on Energy and Commerce sent a letter to the US Food and Drug Administration asking for details on the potential impact of African swine fever on the supply of heparin.²

The US Department of Veterans Affairs (VA) heath care system is currently experiencing a shortage of heparin vials and syringes. It is unclear when resolution of this shortage will occur as it could resolve within several weeks or as late as January 2020.³ Although vials and syringes are the current products that are affected, it is possible the shortage may eventually include IV heparin bags as well.

Since the foremost objective of VA health care providers is to provide timely access to medications for veterans, strategies to conserve unfractionated heparin (UfH) must be used since it is a first-line therapy where few evidence-based alternatives exist. Conservation strategies may include drug rationing, therapeutic substitution, and compounding of needed products using the limited stock available in the pharmacy.⁴ It is important that all staff are educated on facility strategies in order to be familiar with alternatives and limit the potential for near misses, adverse events, and provider frustration.

In shortage situations, the VA-Pharmacy Benefits Management (PBM) defers decisions regarding drug preservation, processes to shift to viable alternatives, and the best practice for safe transitions to local facilities and their subject matter experts.⁵ At the VA Tennessee Valley Healthcare System, a 1A, tertiary, dual campus health care system, a pharmacy task force has formed to track drug shortages impacting the facility’s efficiencies and budgets. This group communicates with the Pharmacy and Therapeutics committee about potential risks to patient care and develops shortage briefs (following an SBAR [situation, background, assessment, recommendation] design) generally authored and championed by at least 1 clinical pharmacy specialist and supervising physicians who are field experts. Prior to dissemination, the SBAR undergoes a rapid peer-review process.

To date, VA PBM has not issued specific guidance on how pharmacists should proceed in case of a shortage. However, we recommend strategies that may be considered for implementation during a potential UfH shortage. For example, pharmacists can use therapeutic alternatives for which best available evidence suggests no disadvantage.⁴ The Table lists alternative agents according to indication and patient-specific considerations that may preclude use. Existing UfH products may also be used for drug compounding (eg, use current stock to provide an indicated aliquot) to meet the need of prioritized patients.⁴ In addition, we suggest prioritizing current UfH/heparinized saline for use for the following groups of patients⁴:

• Emergent/urgent cardiac surgery^1,6;
• Hemodialysis patients^1,7-9 for which the low-molecular-weight heparin (LMWH) dalteparin is deemed inappropriate or the patient is not monitored in the intensive care unit for regional citrate administration;
• VTE prophylaxis for patients with epidurals or chest tubes for which urgent invasive management may occur, recent cardiac or neurosurgery, or for patients with a creatine clearance < 15 mL/min or receiving hemodialysis^10-12;
• Vascular surgery (eg, limb ischemia) and interventions (eg, carotid stenting, endarterectomy)^13,14;
• Mesenteric ischemia (venous thrombosis) with a potential to proceed to laparotomy¹⁵;
• Critically ill patients with arterial lines for which normal saline is deemed inappropriate for line flushing¹⁶;
• Electrophysiology procedures (eg, AF ablation)¹⁷; and
• Contraindication to use of a long-acting alternative listed in the table or a medical necessity exists for using a rapidly reversible agent. Examples for this category include but are not limited to recent gastrointestinal bleeding, central nervous system lesion, and select neurologic diagnoses (eg, cerebral venous sinus thrombosis with hemorrhage, thrombus in vertebral basilar system or anterior circulation, intraparenchymal hemorrhage plus mechanical valve, medium to large cardioembolic stroke with intracardiac thrombus).

Conclusion

The UfH drug shortage represents a significant threat to public health and is a major challenge for US health care systems, including the Veterans Health Administration. Overreliance on a predominant source of crude heparin has affected multiple UfH manufacturers and products. Current alternatives to UfH include low-molecular-weight heparins, IV direct thrombin inhibitors, and SC fondaparinux, with selection supported by guidelines or evolving literature. However, the shortage has the potential to expand to other injectables, such as dalteparin and enoxaparin, and severely limit care for veterans. It is vital that clinicians rapidly address the current shortage by creating a plan to develop efficient and equitable access to UfH, continue to assess supply and update stakeholders, and select evidence-based alternatives while maintaining focus on efficacy and safety.

Acknowledgments

The authors thank Ashley Yost, PharmD, for her coordination of the multidisciplinary task force assigned to efficiently manage the heparin drug shortage. This material is the result of work supported with resources and the use of facilities at the VA Tennessee Valley Healthcare System in Nashville, Tennessee.

Heparin is the anticoagulant of choice when a rapid anticoagulant is indicated: Onset of action is immediate when administered IV as a bolus.¹ The major anticoagulant effect of heparin is mediated by heparin/antithrombin (AT) interaction. Heparin/AT inactivates factor IIa (thrombin) and factors Xa, IXa, XIa, and XIIa. Heparin is approved for multiple indications, such as venous thromboembolism (VTE) treatment and prophylaxis of medical and surgical patients; stroke prevention in atrial fibrillation (AF); acute coronary syndrome (ACS); vascular and cardiac surgeries; and various interventional procedures (eg, diagnostic angiography and percutaneous coronary intervention [PCI]). It also is used as an anticoagulant in blood transfusions, extracorporeal circulation, and for maintaining patency of central vascular access devices (CVADs).

About 60% of the crude heparin used to manufacture heparin in the US originates in China, derived from porcine mucosa. African swine fever, a contagious virus with no cure, has eliminated about 25% to 35% of China’s pig population, or about 150 million pigs. In July 2019, members of the US House of Representatives Committee on Energy and Commerce sent a letter to the US Food and Drug Administration asking for details on the potential impact of African swine fever on the supply of heparin.²

The US Department of Veterans Affairs (VA) heath care system is currently experiencing a shortage of heparin vials and syringes. It is unclear when resolution of this shortage will occur as it could resolve within several weeks or as late as January 2020.³ Although vials and syringes are the current products that are affected, it is possible the shortage may eventually include IV heparin bags as well.

Since the foremost objective of VA health care providers is to provide timely access to medications for veterans, strategies to conserve unfractionated heparin (UfH) must be used since it is a first-line therapy where few evidence-based alternatives exist. Conservation strategies may include drug rationing, therapeutic substitution, and compounding of needed products using the limited stock available in the pharmacy.⁴ It is important that all staff are educated on facility strategies in order to be familiar with alternatives and limit the potential for near misses, adverse events, and provider frustration.

In shortage situations, the VA-Pharmacy Benefits Management (PBM) defers decisions regarding drug preservation, processes to shift to viable alternatives, and the best practice for safe transitions to local facilities and their subject matter experts.⁵ At the VA Tennessee Valley Healthcare System, a 1A, tertiary, dual campus health care system, a pharmacy task force has formed to track drug shortages impacting the facility’s efficiencies and budgets. This group communicates with the Pharmacy and Therapeutics committee about potential risks to patient care and develops shortage briefs (following an SBAR [situation, background, assessment, recommendation] design) generally authored and championed by at least 1 clinical pharmacy specialist and supervising physicians who are field experts. Prior to dissemination, the SBAR undergoes a rapid peer-review process.

To date, VA PBM has not issued specific guidance on how pharmacists should proceed in case of a shortage. However, we recommend strategies that may be considered for implementation during a potential UfH shortage. For example, pharmacists can use therapeutic alternatives for which best available evidence suggests no disadvantage.⁴ The Table lists alternative agents according to indication and patient-specific considerations that may preclude use. Existing UfH products may also be used for drug compounding (eg, use current stock to provide an indicated aliquot) to meet the need of prioritized patients.⁴ In addition, we suggest prioritizing current UfH/heparinized saline for use for the following groups of patients⁴:

• Emergent/urgent cardiac surgery^1,6;
• Hemodialysis patients^1,7-9 for which the low-molecular-weight heparin (LMWH) dalteparin is deemed inappropriate or the patient is not monitored in the intensive care unit for regional citrate administration;
• VTE prophylaxis for patients with epidurals or chest tubes for which urgent invasive management may occur, recent cardiac or neurosurgery, or for patients with a creatine clearance < 15 mL/min or receiving hemodialysis^10-12;
• Vascular surgery (eg, limb ischemia) and interventions (eg, carotid stenting, endarterectomy)^13,14;
• Mesenteric ischemia (venous thrombosis) with a potential to proceed to laparotomy¹⁵;
• Critically ill patients with arterial lines for which normal saline is deemed inappropriate for line flushing¹⁶;
• Electrophysiology procedures (eg, AF ablation)¹⁷; and
• Contraindication to use of a long-acting alternative listed in the table or a medical necessity exists for using a rapidly reversible agent. Examples for this category include but are not limited to recent gastrointestinal bleeding, central nervous system lesion, and select neurologic diagnoses (eg, cerebral venous sinus thrombosis with hemorrhage, thrombus in vertebral basilar system or anterior circulation, intraparenchymal hemorrhage plus mechanical valve, medium to large cardioembolic stroke with intracardiac thrombus).

Conclusion

The UfH drug shortage represents a significant threat to public health and is a major challenge for US health care systems, including the Veterans Health Administration. Overreliance on a predominant source of crude heparin has affected multiple UfH manufacturers and products. Current alternatives to UfH include low-molecular-weight heparins, IV direct thrombin inhibitors, and SC fondaparinux, with selection supported by guidelines or evolving literature. However, the shortage has the potential to expand to other injectables, such as dalteparin and enoxaparin, and severely limit care for veterans. It is vital that clinicians rapidly address the current shortage by creating a plan to develop efficient and equitable access to UfH, continue to assess supply and update stakeholders, and select evidence-based alternatives while maintaining focus on efficacy and safety.

Acknowledgments

The authors thank Ashley Yost, PharmD, for her coordination of the multidisciplinary task force assigned to efficiently manage the heparin drug shortage. This material is the result of work supported with resources and the use of facilities at the VA Tennessee Valley Healthcare System in Nashville, Tennessee.

MADRID – The risks of specific manifestations of antiphospholipid syndrome and systemic lupus erythematosus are linked to the types and levels of antiphospholipid antibodies, according to study findings presented at the European Congress of Rheumatology.

Sara Freeman/MDedge News

Spanish researchers found that the number of antiphospholipid (aPL) antibodies present was important for the development of antiphospholipid syndrome (APS) and that lupus anticoagulant (LA) was the major aPL antibody linked to systemic lupus erythematosus (SLE)–related organ involvement.

“aPL [antibodies] has been extensively associated with an increased risk of thrombosis and poor pregnancy outcomes, mainly in patients with primary APS,” study investigator Leyre Riancho-Zarrabeitia, MD, PhD, explained in an interview ahead of the congress.

“Moreover, aPL [antibody] positivity in SLE has been proposed to be associated with higher damage accrual and with certain manifestations such as valvular heart disease, pulmonary hypertension, and neuropsychiatric manifestations,” she added.

Anticardiolipin antibodies – notably IgG rather than IgM isotypes – also seemed to play an important role in APS and SLE manifestations, Dr. Riancho-Zarrabeitia, of Hospital Sierrallana, Instituto De Investigación Marqués De Valdecilla, and the University of Cantabria (Spain), noted during her oral presentation.

She reported data on 3,651 patients included in the RELESSER registry between October 2011 and August 2012. This large, multicenter, hospital-based registry retrospectively collects immunologic, clinical and demographic data from unselected adult patients with SLE who are attending 45 Spanish rheumatology services within the country’s national health system.

Over one-third (37.5%) of patients, who had a mean age of 47 years and were mostly (90%) women, were positive for aPL. The most frequent aPL detected was IgG anticardiolipin (aCL) antibodies, seen in 25% of patients, followed by LA in 24%, and IgM aCL in 20%.

Of the aPL-positive patients, 20.6% were positive for only one antibody, 12.1% were positive for two antibodies, and 4.8% were positive for three antibodies.

“All types of aPL were associated with classic APS manifestations,” Dr. Riancho-Zarrabeitia said. The associations were strongest for thrombotic events, such as arterial and venous small-vessel thrombosis and recurrent early pregnancy losses.

aCL antibodies conferred the highest risk for arterial thrombosis, she noted (odds ratio, 5.7), whereas LA conferred the highest risk for venous thrombosis (OR, 4.7). Both IgG and IgM isotypes were associated with thrombotic events, fetal death and recurrent pregnancy loss, but the association was stronger with the IgG isotypes.

Having more than one aPL was particularly associated with a higher risk of these APS manifestations. For example, when one antibody was present the OR for arterial thrombosis was 4.45, but when two or more aPL were detected, the ORs rose to 9.23 and 15.6, respectively.

aCL and LA also were associated with thrombocytopenia and hemolytic anemia, with ORs of around 1-2 and 2-3 respectively. There also were antibody associations with cognitive impairments.

Similar results were seen in patients with SLE. “aPL [antibody] positivity in SLE patients influenced the risk for thrombotic and obstetric manifestations,” Dr. Riancho-Zarrabeitia said. LA and aCL were associated with an increased risk of neuropsychiatric manifestations, and LA was linked to an increased risk for renal disease.

The risk for specific SLE manifestations was again higher with IgG isotypes of aCL, notably an increased risk for cardiac and respiratory events.

While increased antibody numbers generally led to a higher risk of complications, the risk for cutaneous manifestations decreased.

“The load of aPL [antibodies] confers a higher risk for APS,” Dr. Riancho-Zarrabeitia said during her conclusion. “Regarding systemic lupus erythematosus, the number of positive antibodies is directly associated with neurological and ophthalmological manifestations, and inversely associated with cutaneous manifestations.”

What these findings show, said Dr. Riancho-Zarrabeitia in the precongress interview, is that individuals who test positive for aPL antibodies need careful monitoring to prevent and treat severe manifestations. “The next step would be to confirm our findings with a prospective study.”

Dr. Riancho-Zarrabeitia has received travel grants from AbbVie, Pfizer, UCB, Merck, GlaxoSmithKline, Amgen, and Roche.

SOURCE: Riancho-Zarrabeitia L et al. Ann Rheum Dis. Jun 2019;78(Suppl 2):136-7. Abstract OP0124. doi: 10.1136/annrheumdis-2019-eular.2485.

MADRID – The risks of specific manifestations of antiphospholipid syndrome and systemic lupus erythematosus are linked to the types and levels of antiphospholipid antibodies, according to study findings presented at the European Congress of Rheumatology.

Sara Freeman/MDedge News

Spanish researchers found that the number of antiphospholipid (aPL) antibodies present was important for the development of antiphospholipid syndrome (APS) and that lupus anticoagulant (LA) was the major aPL antibody linked to systemic lupus erythematosus (SLE)–related organ involvement.

“aPL [antibodies] has been extensively associated with an increased risk of thrombosis and poor pregnancy outcomes, mainly in patients with primary APS,” study investigator Leyre Riancho-Zarrabeitia, MD, PhD, explained in an interview ahead of the congress.

“Moreover, aPL [antibody] positivity in SLE has been proposed to be associated with higher damage accrual and with certain manifestations such as valvular heart disease, pulmonary hypertension, and neuropsychiatric manifestations,” she added.

Anticardiolipin antibodies – notably IgG rather than IgM isotypes – also seemed to play an important role in APS and SLE manifestations, Dr. Riancho-Zarrabeitia, of Hospital Sierrallana, Instituto De Investigación Marqués De Valdecilla, and the University of Cantabria (Spain), noted during her oral presentation.

She reported data on 3,651 patients included in the RELESSER registry between October 2011 and August 2012. This large, multicenter, hospital-based registry retrospectively collects immunologic, clinical and demographic data from unselected adult patients with SLE who are attending 45 Spanish rheumatology services within the country’s national health system.

Over one-third (37.5%) of patients, who had a mean age of 47 years and were mostly (90%) women, were positive for aPL. The most frequent aPL detected was IgG anticardiolipin (aCL) antibodies, seen in 25% of patients, followed by LA in 24%, and IgM aCL in 20%.

Of the aPL-positive patients, 20.6% were positive for only one antibody, 12.1% were positive for two antibodies, and 4.8% were positive for three antibodies.

“All types of aPL were associated with classic APS manifestations,” Dr. Riancho-Zarrabeitia said. The associations were strongest for thrombotic events, such as arterial and venous small-vessel thrombosis and recurrent early pregnancy losses.

aCL antibodies conferred the highest risk for arterial thrombosis, she noted (odds ratio, 5.7), whereas LA conferred the highest risk for venous thrombosis (OR, 4.7). Both IgG and IgM isotypes were associated with thrombotic events, fetal death and recurrent pregnancy loss, but the association was stronger with the IgG isotypes.

Having more than one aPL was particularly associated with a higher risk of these APS manifestations. For example, when one antibody was present the OR for arterial thrombosis was 4.45, but when two or more aPL were detected, the ORs rose to 9.23 and 15.6, respectively.

aCL and LA also were associated with thrombocytopenia and hemolytic anemia, with ORs of around 1-2 and 2-3 respectively. There also were antibody associations with cognitive impairments.

Similar results were seen in patients with SLE. “aPL [antibody] positivity in SLE patients influenced the risk for thrombotic and obstetric manifestations,” Dr. Riancho-Zarrabeitia said. LA and aCL were associated with an increased risk of neuropsychiatric manifestations, and LA was linked to an increased risk for renal disease.

The risk for specific SLE manifestations was again higher with IgG isotypes of aCL, notably an increased risk for cardiac and respiratory events.

While increased antibody numbers generally led to a higher risk of complications, the risk for cutaneous manifestations decreased.

“The load of aPL [antibodies] confers a higher risk for APS,” Dr. Riancho-Zarrabeitia said during her conclusion. “Regarding systemic lupus erythematosus, the number of positive antibodies is directly associated with neurological and ophthalmological manifestations, and inversely associated with cutaneous manifestations.”

What these findings show, said Dr. Riancho-Zarrabeitia in the precongress interview, is that individuals who test positive for aPL antibodies need careful monitoring to prevent and treat severe manifestations. “The next step would be to confirm our findings with a prospective study.”

Dr. Riancho-Zarrabeitia has received travel grants from AbbVie, Pfizer, UCB, Merck, GlaxoSmithKline, Amgen, and Roche.

SOURCE: Riancho-Zarrabeitia L et al. Ann Rheum Dis. Jun 2019;78(Suppl 2):136-7. Abstract OP0124. doi: 10.1136/annrheumdis-2019-eular.2485.

MADRID – The risks of specific manifestations of antiphospholipid syndrome and systemic lupus erythematosus are linked to the types and levels of antiphospholipid antibodies, according to study findings presented at the European Congress of Rheumatology.

Sara Freeman/MDedge News

Spanish researchers found that the number of antiphospholipid (aPL) antibodies present was important for the development of antiphospholipid syndrome (APS) and that lupus anticoagulant (LA) was the major aPL antibody linked to systemic lupus erythematosus (SLE)–related organ involvement.

“aPL [antibodies] has been extensively associated with an increased risk of thrombosis and poor pregnancy outcomes, mainly in patients with primary APS,” study investigator Leyre Riancho-Zarrabeitia, MD, PhD, explained in an interview ahead of the congress.

“Moreover, aPL [antibody] positivity in SLE has been proposed to be associated with higher damage accrual and with certain manifestations such as valvular heart disease, pulmonary hypertension, and neuropsychiatric manifestations,” she added.

Anticardiolipin antibodies – notably IgG rather than IgM isotypes – also seemed to play an important role in APS and SLE manifestations, Dr. Riancho-Zarrabeitia, of Hospital Sierrallana, Instituto De Investigación Marqués De Valdecilla, and the University of Cantabria (Spain), noted during her oral presentation.

She reported data on 3,651 patients included in the RELESSER registry between October 2011 and August 2012. This large, multicenter, hospital-based registry retrospectively collects immunologic, clinical and demographic data from unselected adult patients with SLE who are attending 45 Spanish rheumatology services within the country’s national health system.

Over one-third (37.5%) of patients, who had a mean age of 47 years and were mostly (90%) women, were positive for aPL. The most frequent aPL detected was IgG anticardiolipin (aCL) antibodies, seen in 25% of patients, followed by LA in 24%, and IgM aCL in 20%.

Of the aPL-positive patients, 20.6% were positive for only one antibody, 12.1% were positive for two antibodies, and 4.8% were positive for three antibodies.

“All types of aPL were associated with classic APS manifestations,” Dr. Riancho-Zarrabeitia said. The associations were strongest for thrombotic events, such as arterial and venous small-vessel thrombosis and recurrent early pregnancy losses.

aCL antibodies conferred the highest risk for arterial thrombosis, she noted (odds ratio, 5.7), whereas LA conferred the highest risk for venous thrombosis (OR, 4.7). Both IgG and IgM isotypes were associated with thrombotic events, fetal death and recurrent pregnancy loss, but the association was stronger with the IgG isotypes.

Having more than one aPL was particularly associated with a higher risk of these APS manifestations. For example, when one antibody was present the OR for arterial thrombosis was 4.45, but when two or more aPL were detected, the ORs rose to 9.23 and 15.6, respectively.

aCL and LA also were associated with thrombocytopenia and hemolytic anemia, with ORs of around 1-2 and 2-3 respectively. There also were antibody associations with cognitive impairments.

Similar results were seen in patients with SLE. “aPL [antibody] positivity in SLE patients influenced the risk for thrombotic and obstetric manifestations,” Dr. Riancho-Zarrabeitia said. LA and aCL were associated with an increased risk of neuropsychiatric manifestations, and LA was linked to an increased risk for renal disease.

The risk for specific SLE manifestations was again higher with IgG isotypes of aCL, notably an increased risk for cardiac and respiratory events.

While increased antibody numbers generally led to a higher risk of complications, the risk for cutaneous manifestations decreased.

“The load of aPL [antibodies] confers a higher risk for APS,” Dr. Riancho-Zarrabeitia said during her conclusion. “Regarding systemic lupus erythematosus, the number of positive antibodies is directly associated with neurological and ophthalmological manifestations, and inversely associated with cutaneous manifestations.”

What these findings show, said Dr. Riancho-Zarrabeitia in the precongress interview, is that individuals who test positive for aPL antibodies need careful monitoring to prevent and treat severe manifestations. “The next step would be to confirm our findings with a prospective study.”

Dr. Riancho-Zarrabeitia has received travel grants from AbbVie, Pfizer, UCB, Merck, GlaxoSmithKline, Amgen, and Roche.

SOURCE: Riancho-Zarrabeitia L et al. Ann Rheum Dis. Jun 2019;78(Suppl 2):136-7. Abstract OP0124. doi: 10.1136/annrheumdis-2019-eular.2485.

NEW ORLEANS – The incidence of pulmonary embolism diagnosed in hospitalized U.S. patients nearly doubled during the period 2004-2015 based on data collected by the National Inpatient Sample.

During 2004-2015 the incidence of all diagnosed pulmonary embolism (PE), based on discharge diagnoses, rose from 5.4 cases/1,000 hospitalized patients in 2004 to 9.7 cases/1,000 hospitalized patients in 2015, an 80% increase, Joshua B. Goldberg, MD said at the annual meeting of the American College of Cardiology. The incidence of major PE – defined as a patient who needed vasopressor treatment, mechanical ventilation, or had nonseptic shock – rose from 7.9% of all hospitalized PE diagnoses in 2004 to 9.7% in 2015, a 23% relative increase.

Mitchel L. Zoler/MDedge News

The data also documented a shifting pattern of treatment for all hospitalized patients with PE, and especially among patients with major PE. During the study period, treatment with systemic thrombolysis for all PE rose nearly threefold, and catheter-directed therapy began to show a steady rise in use from 0.2% of all patients in 2011 (and before) to 1% of all patients by 2015. Surgical intervention remained lightly used throughout, with about 0.2% of all PE patients undergoing surgery annually.

Most of these intervention options focused on patients with major PE. Among patients in this subgroup with more severe disease, use of one of these three types of interventions rose from 6% in 2004 to 12% in 2015, mostly driven by a rise in systemic thrombolysis, which jumped from 3% of major PE in 2004 to 9% in 2015. However, the efficacy of systemic thrombolysis in patients with major PE remains suspect. In 2004, 39% of patients with major PE treated with systemic thrombolysis died in hospital; in 2015 the number was 47%. “The data don’t support using systemic thrombolysis to treat major PE; the mortality is high,” noted Dr. Goldberg, a cardiothoracic surgeon at Westchester Medical Center in Valhalla, N.Y.

Although catheter-directed therapy began to be much more widely used in U.S. practice starting in about 2015, during the period studied its use for major PE held fairly steady at roughly 2%-3%, but this approach also showed substantial shortcomings for the major PE population. These sicker patients treated with catheter-directed therapy had 37% mortality in 2004 and a 31% mortality in 2015, a difference that was not statistically significant. In general, PE patients enrolled in the catheter-directed therapy trials were not as sick as the major PE patients who get treated with surgery in routine practice, Dr. Goldberg said in an interview.

The data showed much better performance using surgery, although only 1,237 patients of the entire group of 713,083 PE patients studied in the database underwent surgical embolectomy. Overall, in-hospital mortality in these patients was 22%, but in a time trend analysis, mortality among all PE patients treated with surgery fell from 32% in 2004 to 14% in 2015; among patients with major PE treated with surgery, mortality fell from 52% in 2004 to 21% in 2015.

Dr. Goldberg attributed the success of surgery in severe PE patients to the definitive nature of embolectomy and the concurrent use of extracorporeal membrane oxygenation that helps stabilize acutely ill PE patients. He also cited refinements that surgery underwent during the 2004-2015 period based on the experience managing chronic thromboembolic pulmonary hypertension, including routine use of cardiopulmonary bypass during surgery. “Very high risk [PE] patients should go straight to surgery, unless the patient is at high risk for surgery because of conditions like prior sternotomy or very advanced age, in which case catheter-directed therapy may be a safer option, he said. He cited a recent 5% death rate after surgery at his center among patients with major PE who did not require cardiopulmonary resuscitation.

The database Dr. Goldberg and his collaborator reviewed included 12,735 patients treated by systemic thrombolysis, and 2,595 treated by catheter-directed therapy. Patients averaged 63 years old. The most common indicator of major PE was mechanical ventilation, used on 8% of all PE patients in the study. Non-septic shock occurred in 2%, and just under 1% needed vasopressor treatment.

Published guidelines on PE management from several medical groups are “vague and have numerous caveats,” Dr. Goldberg said. He is participating in an update to the 2011 PE management statement from the American College of Cardiology and American Heart Association (Circulation. 2011 April 26;123[16]:1788-1830).

The study received no commercial funding. Dr. Goldberg had no disclosures.

mzoler@mdedge.com

SOURCE: Haider A et al. J Amer Coll Cardiol. 2019 March;73:9[suppl 1]: doi: 10.1016/S0735-1097(19)32507-0

NEW ORLEANS – The incidence of pulmonary embolism diagnosed in hospitalized U.S. patients nearly doubled during the period 2004-2015 based on data collected by the National Inpatient Sample.

During 2004-2015 the incidence of all diagnosed pulmonary embolism (PE), based on discharge diagnoses, rose from 5.4 cases/1,000 hospitalized patients in 2004 to 9.7 cases/1,000 hospitalized patients in 2015, an 80% increase, Joshua B. Goldberg, MD said at the annual meeting of the American College of Cardiology. The incidence of major PE – defined as a patient who needed vasopressor treatment, mechanical ventilation, or had nonseptic shock – rose from 7.9% of all hospitalized PE diagnoses in 2004 to 9.7% in 2015, a 23% relative increase.

Mitchel L. Zoler/MDedge News

The data also documented a shifting pattern of treatment for all hospitalized patients with PE, and especially among patients with major PE. During the study period, treatment with systemic thrombolysis for all PE rose nearly threefold, and catheter-directed therapy began to show a steady rise in use from 0.2% of all patients in 2011 (and before) to 1% of all patients by 2015. Surgical intervention remained lightly used throughout, with about 0.2% of all PE patients undergoing surgery annually.

Most of these intervention options focused on patients with major PE. Among patients in this subgroup with more severe disease, use of one of these three types of interventions rose from 6% in 2004 to 12% in 2015, mostly driven by a rise in systemic thrombolysis, which jumped from 3% of major PE in 2004 to 9% in 2015. However, the efficacy of systemic thrombolysis in patients with major PE remains suspect. In 2004, 39% of patients with major PE treated with systemic thrombolysis died in hospital; in 2015 the number was 47%. “The data don’t support using systemic thrombolysis to treat major PE; the mortality is high,” noted Dr. Goldberg, a cardiothoracic surgeon at Westchester Medical Center in Valhalla, N.Y.

Although catheter-directed therapy began to be much more widely used in U.S. practice starting in about 2015, during the period studied its use for major PE held fairly steady at roughly 2%-3%, but this approach also showed substantial shortcomings for the major PE population. These sicker patients treated with catheter-directed therapy had 37% mortality in 2004 and a 31% mortality in 2015, a difference that was not statistically significant. In general, PE patients enrolled in the catheter-directed therapy trials were not as sick as the major PE patients who get treated with surgery in routine practice, Dr. Goldberg said in an interview.

The data showed much better performance using surgery, although only 1,237 patients of the entire group of 713,083 PE patients studied in the database underwent surgical embolectomy. Overall, in-hospital mortality in these patients was 22%, but in a time trend analysis, mortality among all PE patients treated with surgery fell from 32% in 2004 to 14% in 2015; among patients with major PE treated with surgery, mortality fell from 52% in 2004 to 21% in 2015.

Dr. Goldberg attributed the success of surgery in severe PE patients to the definitive nature of embolectomy and the concurrent use of extracorporeal membrane oxygenation that helps stabilize acutely ill PE patients. He also cited refinements that surgery underwent during the 2004-2015 period based on the experience managing chronic thromboembolic pulmonary hypertension, including routine use of cardiopulmonary bypass during surgery. “Very high risk [PE] patients should go straight to surgery, unless the patient is at high risk for surgery because of conditions like prior sternotomy or very advanced age, in which case catheter-directed therapy may be a safer option, he said. He cited a recent 5% death rate after surgery at his center among patients with major PE who did not require cardiopulmonary resuscitation.

The database Dr. Goldberg and his collaborator reviewed included 12,735 patients treated by systemic thrombolysis, and 2,595 treated by catheter-directed therapy. Patients averaged 63 years old. The most common indicator of major PE was mechanical ventilation, used on 8% of all PE patients in the study. Non-septic shock occurred in 2%, and just under 1% needed vasopressor treatment.

Published guidelines on PE management from several medical groups are “vague and have numerous caveats,” Dr. Goldberg said. He is participating in an update to the 2011 PE management statement from the American College of Cardiology and American Heart Association (Circulation. 2011 April 26;123[16]:1788-1830).

The study received no commercial funding. Dr. Goldberg had no disclosures.

mzoler@mdedge.com

SOURCE: Haider A et al. J Amer Coll Cardiol. 2019 March;73:9[suppl 1]: doi: 10.1016/S0735-1097(19)32507-0

NEW ORLEANS – The incidence of pulmonary embolism diagnosed in hospitalized U.S. patients nearly doubled during the period 2004-2015 based on data collected by the National Inpatient Sample.

During 2004-2015 the incidence of all diagnosed pulmonary embolism (PE), based on discharge diagnoses, rose from 5.4 cases/1,000 hospitalized patients in 2004 to 9.7 cases/1,000 hospitalized patients in 2015, an 80% increase, Joshua B. Goldberg, MD said at the annual meeting of the American College of Cardiology. The incidence of major PE – defined as a patient who needed vasopressor treatment, mechanical ventilation, or had nonseptic shock – rose from 7.9% of all hospitalized PE diagnoses in 2004 to 9.7% in 2015, a 23% relative increase.

Mitchel L. Zoler/MDedge News

The data also documented a shifting pattern of treatment for all hospitalized patients with PE, and especially among patients with major PE. During the study period, treatment with systemic thrombolysis for all PE rose nearly threefold, and catheter-directed therapy began to show a steady rise in use from 0.2% of all patients in 2011 (and before) to 1% of all patients by 2015. Surgical intervention remained lightly used throughout, with about 0.2% of all PE patients undergoing surgery annually.

Most of these intervention options focused on patients with major PE. Among patients in this subgroup with more severe disease, use of one of these three types of interventions rose from 6% in 2004 to 12% in 2015, mostly driven by a rise in systemic thrombolysis, which jumped from 3% of major PE in 2004 to 9% in 2015. However, the efficacy of systemic thrombolysis in patients with major PE remains suspect. In 2004, 39% of patients with major PE treated with systemic thrombolysis died in hospital; in 2015 the number was 47%. “The data don’t support using systemic thrombolysis to treat major PE; the mortality is high,” noted Dr. Goldberg, a cardiothoracic surgeon at Westchester Medical Center in Valhalla, N.Y.

Although catheter-directed therapy began to be much more widely used in U.S. practice starting in about 2015, during the period studied its use for major PE held fairly steady at roughly 2%-3%, but this approach also showed substantial shortcomings for the major PE population. These sicker patients treated with catheter-directed therapy had 37% mortality in 2004 and a 31% mortality in 2015, a difference that was not statistically significant. In general, PE patients enrolled in the catheter-directed therapy trials were not as sick as the major PE patients who get treated with surgery in routine practice, Dr. Goldberg said in an interview.

The data showed much better performance using surgery, although only 1,237 patients of the entire group of 713,083 PE patients studied in the database underwent surgical embolectomy. Overall, in-hospital mortality in these patients was 22%, but in a time trend analysis, mortality among all PE patients treated with surgery fell from 32% in 2004 to 14% in 2015; among patients with major PE treated with surgery, mortality fell from 52% in 2004 to 21% in 2015.

Dr. Goldberg attributed the success of surgery in severe PE patients to the definitive nature of embolectomy and the concurrent use of extracorporeal membrane oxygenation that helps stabilize acutely ill PE patients. He also cited refinements that surgery underwent during the 2004-2015 period based on the experience managing chronic thromboembolic pulmonary hypertension, including routine use of cardiopulmonary bypass during surgery. “Very high risk [PE] patients should go straight to surgery, unless the patient is at high risk for surgery because of conditions like prior sternotomy or very advanced age, in which case catheter-directed therapy may be a safer option, he said. He cited a recent 5% death rate after surgery at his center among patients with major PE who did not require cardiopulmonary resuscitation.

The database Dr. Goldberg and his collaborator reviewed included 12,735 patients treated by systemic thrombolysis, and 2,595 treated by catheter-directed therapy. Patients averaged 63 years old. The most common indicator of major PE was mechanical ventilation, used on 8% of all PE patients in the study. Non-septic shock occurred in 2%, and just under 1% needed vasopressor treatment.

Published guidelines on PE management from several medical groups are “vague and have numerous caveats,” Dr. Goldberg said. He is participating in an update to the 2011 PE management statement from the American College of Cardiology and American Heart Association (Circulation. 2011 April 26;123[16]:1788-1830).

The study received no commercial funding. Dr. Goldberg had no disclosures.

mzoler@mdedge.com

SOURCE: Haider A et al. J Amer Coll Cardiol. 2019 March;73:9[suppl 1]: doi: 10.1016/S0735-1097(19)32507-0

A diagnostic algorithm adapted for use in pregnancy safely ruled out acute pulmonary embolism in nearly 500 women with suspected pulmonary embolism enrolled in a recent prospective study, investigators are reporting.

Using the adapted algorithm, there was only one deep-vein thrombosis (DVT) and no pulmonary embolism (PE) in follow-up among those women, according to the investigators, including senior author Menno V. Huisman, MD, PhD, of the department of thrombosis and hemostasis at Leiden (Netherlands) University Medical Center and his coauthors.

Courtesy Wikimedia Commons/Walter Serra, Giuseppe De Iaco, Claudio Reverberi, and Tiziano Gherli/Creative Commons License

The main advantage of the algorithm is that it averted CT pulmonary angiography in nearly 40% of patients, thus sparing radiation exposure to mother and fetus in many cases, the investigators added.

“Our algorithm provides solid evidence for the safe management of suspected PE in pregnant women, with selective use of CT pulmonary angiography,” Dr. Huisman and colleagues said in their March 21 report in the New England Journal of Medicine.

In a previous clinical trial, known as the YEARS study, a specialized diagnostic algorithm had a low incidence of failure in men and women with clinically suspected PE, as shown by a venous thromboembolism (VTE) rate of just 0.61% at 3 months and by use of CT pulmonary angiography that was 14 percentage points lower than with a conventional algorithmic approach.

For the current study, Dr. Huisman and his coinvestigators took the YEARS algorithm and adapted it for use in pregnant women with suspected PE presenting at 1 of 18 centers in the Netherlands, France, and Ireland.

Their adapted algorithm was based on the three criteria investigators said were most predictive in the YEARS trial, namely, clinical signs of symptoms of DVT, hemoptysis, and PE as the most likely diagnosis. Patients also underwent D-dimer testing, and if they had clinical signs and symptoms of DVT, underwent compression utrasonography of the symptomatic leg.

Pulmonary embolism was considered ruled out in patients who met none of the three YEARS criteria and had a D-dimer under 1,000 ng/mL, or if they met one to three YEARS criteria and had a D-dimer under 500 ng/mL. Otherwise, patients underwent CT pulmonary angiography and started anticoagulant treatment if results of that test indicated PE.

The primary endpoint of the study was the cumulative 3-month incidence of symptomatic VTE among patients with PE ruled out by this algorithm.

Of 498 patients participating in the study, 477 (96%) had a negative result on the adapted YEARS algorithm at baseline, while 20 (4.0%) received a diagnosis of PE, according to results of the study. One patient was lost to follow-up.

Of the 477 patients with negative results, 1 patient (0.21%) had a diagnosis of symptomatic DVT over the 3 months of follow-up, investigators reported, adding that there were no PE diagnoses over the follow-up period.

That patient with the DVT diagnosis met none of the three YEARS criteria and had a D-dimer level of 480 ng/mL, and so did not undergo CT pulmonary angiography, investigators said.

In the worst-case scenario, the VTE incidence would have been 0.42%, assuming the one patient lost to follow-up would have had a VTE diagnosis over the 3-month follow-up period, they added.

“These data meet the proposed criteria for assessing the safety of diagnostic methods in VTE, even in the context of a low baseline prevalence of disease,” Dr. Huisman and his colleagues wrote.

Overall, CT pulmonary angiography was avoided – avoiding potential radiation exposure-related harms– in 39% of the patients, the investigators said, noting that the proportion of women avoiding the diagnostic test decreased from 65% for those evaluated in the third trimester, 46% in the second trimester, and 32% in the third.

“This decreasing specificity can be explained by the physiological rise in the D-dimer level that commonly occurs during pregnancy,” said Dr. Huisman and his coauthors.

The study was supported by unrestricted grants from Leiden University Medical Center and 17 other participating hospitals. Many authors reported financial ties to the pharmaceutical industry.

SOURCE: van der Pol LM et al. N Engl J Med. 2019;380:1139-49

A diagnostic algorithm adapted for use in pregnancy safely ruled out acute pulmonary embolism in nearly 500 women with suspected pulmonary embolism enrolled in a recent prospective study, investigators are reporting.

Using the adapted algorithm, there was only one deep-vein thrombosis (DVT) and no pulmonary embolism (PE) in follow-up among those women, according to the investigators, including senior author Menno V. Huisman, MD, PhD, of the department of thrombosis and hemostasis at Leiden (Netherlands) University Medical Center and his coauthors.

Courtesy Wikimedia Commons/Walter Serra, Giuseppe De Iaco, Claudio Reverberi, and Tiziano Gherli/Creative Commons License

The main advantage of the algorithm is that it averted CT pulmonary angiography in nearly 40% of patients, thus sparing radiation exposure to mother and fetus in many cases, the investigators added.

“Our algorithm provides solid evidence for the safe management of suspected PE in pregnant women, with selective use of CT pulmonary angiography,” Dr. Huisman and colleagues said in their March 21 report in the New England Journal of Medicine.

In a previous clinical trial, known as the YEARS study, a specialized diagnostic algorithm had a low incidence of failure in men and women with clinically suspected PE, as shown by a venous thromboembolism (VTE) rate of just 0.61% at 3 months and by use of CT pulmonary angiography that was 14 percentage points lower than with a conventional algorithmic approach.

For the current study, Dr. Huisman and his coinvestigators took the YEARS algorithm and adapted it for use in pregnant women with suspected PE presenting at 1 of 18 centers in the Netherlands, France, and Ireland.

Their adapted algorithm was based on the three criteria investigators said were most predictive in the YEARS trial, namely, clinical signs of symptoms of DVT, hemoptysis, and PE as the most likely diagnosis. Patients also underwent D-dimer testing, and if they had clinical signs and symptoms of DVT, underwent compression utrasonography of the symptomatic leg.

Pulmonary embolism was considered ruled out in patients who met none of the three YEARS criteria and had a D-dimer under 1,000 ng/mL, or if they met one to three YEARS criteria and had a D-dimer under 500 ng/mL. Otherwise, patients underwent CT pulmonary angiography and started anticoagulant treatment if results of that test indicated PE.

The primary endpoint of the study was the cumulative 3-month incidence of symptomatic VTE among patients with PE ruled out by this algorithm.

Of 498 patients participating in the study, 477 (96%) had a negative result on the adapted YEARS algorithm at baseline, while 20 (4.0%) received a diagnosis of PE, according to results of the study. One patient was lost to follow-up.

Of the 477 patients with negative results, 1 patient (0.21%) had a diagnosis of symptomatic DVT over the 3 months of follow-up, investigators reported, adding that there were no PE diagnoses over the follow-up period.

That patient with the DVT diagnosis met none of the three YEARS criteria and had a D-dimer level of 480 ng/mL, and so did not undergo CT pulmonary angiography, investigators said.

In the worst-case scenario, the VTE incidence would have been 0.42%, assuming the one patient lost to follow-up would have had a VTE diagnosis over the 3-month follow-up period, they added.

“These data meet the proposed criteria for assessing the safety of diagnostic methods in VTE, even in the context of a low baseline prevalence of disease,” Dr. Huisman and his colleagues wrote.

Overall, CT pulmonary angiography was avoided – avoiding potential radiation exposure-related harms– in 39% of the patients, the investigators said, noting that the proportion of women avoiding the diagnostic test decreased from 65% for those evaluated in the third trimester, 46% in the second trimester, and 32% in the third.

“This decreasing specificity can be explained by the physiological rise in the D-dimer level that commonly occurs during pregnancy,” said Dr. Huisman and his coauthors.

The study was supported by unrestricted grants from Leiden University Medical Center and 17 other participating hospitals. Many authors reported financial ties to the pharmaceutical industry.

SOURCE: van der Pol LM et al. N Engl J Med. 2019;380:1139-49

A diagnostic algorithm adapted for use in pregnancy safely ruled out acute pulmonary embolism in nearly 500 women with suspected pulmonary embolism enrolled in a recent prospective study, investigators are reporting.

Using the adapted algorithm, there was only one deep-vein thrombosis (DVT) and no pulmonary embolism (PE) in follow-up among those women, according to the investigators, including senior author Menno V. Huisman, MD, PhD, of the department of thrombosis and hemostasis at Leiden (Netherlands) University Medical Center and his coauthors.

Courtesy Wikimedia Commons/Walter Serra, Giuseppe De Iaco, Claudio Reverberi, and Tiziano Gherli/Creative Commons License

The main advantage of the algorithm is that it averted CT pulmonary angiography in nearly 40% of patients, thus sparing radiation exposure to mother and fetus in many cases, the investigators added.

“Our algorithm provides solid evidence for the safe management of suspected PE in pregnant women, with selective use of CT pulmonary angiography,” Dr. Huisman and colleagues said in their March 21 report in the New England Journal of Medicine.

In a previous clinical trial, known as the YEARS study, a specialized diagnostic algorithm had a low incidence of failure in men and women with clinically suspected PE, as shown by a venous thromboembolism (VTE) rate of just 0.61% at 3 months and by use of CT pulmonary angiography that was 14 percentage points lower than with a conventional algorithmic approach.

For the current study, Dr. Huisman and his coinvestigators took the YEARS algorithm and adapted it for use in pregnant women with suspected PE presenting at 1 of 18 centers in the Netherlands, France, and Ireland.

Their adapted algorithm was based on the three criteria investigators said were most predictive in the YEARS trial, namely, clinical signs of symptoms of DVT, hemoptysis, and PE as the most likely diagnosis. Patients also underwent D-dimer testing, and if they had clinical signs and symptoms of DVT, underwent compression utrasonography of the symptomatic leg.

Pulmonary embolism was considered ruled out in patients who met none of the three YEARS criteria and had a D-dimer under 1,000 ng/mL, or if they met one to three YEARS criteria and had a D-dimer under 500 ng/mL. Otherwise, patients underwent CT pulmonary angiography and started anticoagulant treatment if results of that test indicated PE.

The primary endpoint of the study was the cumulative 3-month incidence of symptomatic VTE among patients with PE ruled out by this algorithm.

Of 498 patients participating in the study, 477 (96%) had a negative result on the adapted YEARS algorithm at baseline, while 20 (4.0%) received a diagnosis of PE, according to results of the study. One patient was lost to follow-up.

Of the 477 patients with negative results, 1 patient (0.21%) had a diagnosis of symptomatic DVT over the 3 months of follow-up, investigators reported, adding that there were no PE diagnoses over the follow-up period.

That patient with the DVT diagnosis met none of the three YEARS criteria and had a D-dimer level of 480 ng/mL, and so did not undergo CT pulmonary angiography, investigators said.

In the worst-case scenario, the VTE incidence would have been 0.42%, assuming the one patient lost to follow-up would have had a VTE diagnosis over the 3-month follow-up period, they added.

“These data meet the proposed criteria for assessing the safety of diagnostic methods in VTE, even in the context of a low baseline prevalence of disease,” Dr. Huisman and his colleagues wrote.

Overall, CT pulmonary angiography was avoided – avoiding potential radiation exposure-related harms– in 39% of the patients, the investigators said, noting that the proportion of women avoiding the diagnostic test decreased from 65% for those evaluated in the third trimester, 46% in the second trimester, and 32% in the third.

“This decreasing specificity can be explained by the physiological rise in the D-dimer level that commonly occurs during pregnancy,” said Dr. Huisman and his coauthors.

The study was supported by unrestricted grants from Leiden University Medical Center and 17 other participating hospitals. Many authors reported financial ties to the pharmaceutical industry.

SOURCE: van der Pol LM et al. N Engl J Med. 2019;380:1139-49

SEATTLE – HIV infection is associated with increased risk of recurrent venous thromboembolism, especially within 1 year of the initial episode. The finding, presented during a poster session at the Conference on Retroviruses & Opportunistic Infections, follows up on an earlier study that found that first-time VTE risk also is higher among HIV-positive individuals than in the general population.

Jim Kling/MDedge News

The conclusion about first-time VTE risk, published earlier this year in Lancet HIV, came from a comparison between the ATHENA (AIDS Therapy Evaluation in the Netherlands) cohort and European population-level of studies of VTE. It found a crude incidence of 2.33 VTE events per 1,000 person-years In HIV patients, with heightened odds when CD4 cell counts were below 200 cells/mcL (adjusted hazard ratio, 3.40).

The new work represents a follow-up and compared results from ATHENA (153 patients with HIV and first VTE) and the Dutch MEGA cohort (4,005 patients without HIV, with first VTE), which includes the general population. Overall, 26% of patients in the ATHENA cohort experienced a second VTE event, compared with 16% of the general population. At 1 year after anticoagulation withdrawal, HIV-positive individuals were at 67% increased risk (HR, 1.67). At 6-years after withdrawal, the relationship was not statistically significant (HR, 1.22).

Researchers also found that CD4 cell-count recovery was associated with lowered risk, with every 100 cell-count increase between initial VTE diagnosis and anticoagulant withdrawal linked to a 20% reduction in risk (HR, 0.80).

“The clinical question is: If it’s true you have an increased risk of recurrence, should you be continuing anticoagulant therapy longer in people with HIV? This poster doesn’t answer that question and you probably need a randomized, controlled trial to look at that,” Peter Reiss, MD, professor of medicine at Amsterdam University Medical Center, said in an interview during the conference.

In the absence of a clear answer, it’s sensible for clinicians to be aware of the potential increased risk, much as clinicians have internalized the increased risk of atherosclerotic vascular disease in HIV patients. “I think the publication [in Lancet HIV] as well as this poster suggest that on the venous side of things there may also be an accentuated risk,” said Dr. Reiss.

Heidi Crane, MD, a professor of medicine at the University of Washington, Seattle, presented a poster examining the underlying factors that may predispose HIV patients to first-time VTE events. Her team performed an adjudicated review of VTE cases among HIV patients at six institutions and found that the risk factors appeared to be distinct from those seen in the general population.

The traditional long plane ride was less common in this population, while factors such as injected drug use and pneumonia were more common. The VTE events occurred at a median age of 49 years; 30% of the patients had a detectable viral load. “We’re seeing a little more (VTE) than you might expect, and in a younger population than you might have guessed,” said Dr. Crane in an interview.

The most frequent predisposing risk factors were recent hospitalization (40%), infection (40%), or immobilization/bed rest (24%) within the past 90 days, and injectable drug use (22%). “It’s not just the traditional risk factors. Some HIV-specific risk factors are driving this,” said Dr. Crane.

She also aims to learn more about the specifics of risk factors, such as catheter-associated thromboses. The team is working to increase the sample size in order to parse out the relationships with specific outcomes.

In the meantime, the data further characterize the health challenges facing people living with HIV. “This is another example demonstrating that comorbid conditions among patients with HIV that are often considered age related occur at much younger ages in our population,” said Dr. Crane.

SOURCE: Rokx C et al. CROI 2019, Abstract 636; and Tenforde MW et al. CROI 2019, Abstract 637.

.

SEATTLE – HIV infection is associated with increased risk of recurrent venous thromboembolism, especially within 1 year of the initial episode. The finding, presented during a poster session at the Conference on Retroviruses & Opportunistic Infections, follows up on an earlier study that found that first-time VTE risk also is higher among HIV-positive individuals than in the general population.

Jim Kling/MDedge News

The conclusion about first-time VTE risk, published earlier this year in Lancet HIV, came from a comparison between the ATHENA (AIDS Therapy Evaluation in the Netherlands) cohort and European population-level of studies of VTE. It found a crude incidence of 2.33 VTE events per 1,000 person-years In HIV patients, with heightened odds when CD4 cell counts were below 200 cells/mcL (adjusted hazard ratio, 3.40).

The new work represents a follow-up and compared results from ATHENA (153 patients with HIV and first VTE) and the Dutch MEGA cohort (4,005 patients without HIV, with first VTE), which includes the general population. Overall, 26% of patients in the ATHENA cohort experienced a second VTE event, compared with 16% of the general population. At 1 year after anticoagulation withdrawal, HIV-positive individuals were at 67% increased risk (HR, 1.67). At 6-years after withdrawal, the relationship was not statistically significant (HR, 1.22).

Researchers also found that CD4 cell-count recovery was associated with lowered risk, with every 100 cell-count increase between initial VTE diagnosis and anticoagulant withdrawal linked to a 20% reduction in risk (HR, 0.80).

“The clinical question is: If it’s true you have an increased risk of recurrence, should you be continuing anticoagulant therapy longer in people with HIV? This poster doesn’t answer that question and you probably need a randomized, controlled trial to look at that,” Peter Reiss, MD, professor of medicine at Amsterdam University Medical Center, said in an interview during the conference.

In the absence of a clear answer, it’s sensible for clinicians to be aware of the potential increased risk, much as clinicians have internalized the increased risk of atherosclerotic vascular disease in HIV patients. “I think the publication [in Lancet HIV] as well as this poster suggest that on the venous side of things there may also be an accentuated risk,” said Dr. Reiss.

Heidi Crane, MD, a professor of medicine at the University of Washington, Seattle, presented a poster examining the underlying factors that may predispose HIV patients to first-time VTE events. Her team performed an adjudicated review of VTE cases among HIV patients at six institutions and found that the risk factors appeared to be distinct from those seen in the general population.

The traditional long plane ride was less common in this population, while factors such as injected drug use and pneumonia were more common. The VTE events occurred at a median age of 49 years; 30% of the patients had a detectable viral load. “We’re seeing a little more (VTE) than you might expect, and in a younger population than you might have guessed,” said Dr. Crane in an interview.

The most frequent predisposing risk factors were recent hospitalization (40%), infection (40%), or immobilization/bed rest (24%) within the past 90 days, and injectable drug use (22%). “It’s not just the traditional risk factors. Some HIV-specific risk factors are driving this,” said Dr. Crane.

She also aims to learn more about the specifics of risk factors, such as catheter-associated thromboses. The team is working to increase the sample size in order to parse out the relationships with specific outcomes.

In the meantime, the data further characterize the health challenges facing people living with HIV. “This is another example demonstrating that comorbid conditions among patients with HIV that are often considered age related occur at much younger ages in our population,” said Dr. Crane.

SOURCE: Rokx C et al. CROI 2019, Abstract 636; and Tenforde MW et al. CROI 2019, Abstract 637.

.

SEATTLE – HIV infection is associated with increased risk of recurrent venous thromboembolism, especially within 1 year of the initial episode. The finding, presented during a poster session at the Conference on Retroviruses & Opportunistic Infections, follows up on an earlier study that found that first-time VTE risk also is higher among HIV-positive individuals than in the general population.

Jim Kling/MDedge News

The conclusion about first-time VTE risk, published earlier this year in Lancet HIV, came from a comparison between the ATHENA (AIDS Therapy Evaluation in the Netherlands) cohort and European population-level of studies of VTE. It found a crude incidence of 2.33 VTE events per 1,000 person-years In HIV patients, with heightened odds when CD4 cell counts were below 200 cells/mcL (adjusted hazard ratio, 3.40).

The new work represents a follow-up and compared results from ATHENA (153 patients with HIV and first VTE) and the Dutch MEGA cohort (4,005 patients without HIV, with first VTE), which includes the general population. Overall, 26% of patients in the ATHENA cohort experienced a second VTE event, compared with 16% of the general population. At 1 year after anticoagulation withdrawal, HIV-positive individuals were at 67% increased risk (HR, 1.67). At 6-years after withdrawal, the relationship was not statistically significant (HR, 1.22).

Researchers also found that CD4 cell-count recovery was associated with lowered risk, with every 100 cell-count increase between initial VTE diagnosis and anticoagulant withdrawal linked to a 20% reduction in risk (HR, 0.80).

“The clinical question is: If it’s true you have an increased risk of recurrence, should you be continuing anticoagulant therapy longer in people with HIV? This poster doesn’t answer that question and you probably need a randomized, controlled trial to look at that,” Peter Reiss, MD, professor of medicine at Amsterdam University Medical Center, said in an interview during the conference.

In the absence of a clear answer, it’s sensible for clinicians to be aware of the potential increased risk, much as clinicians have internalized the increased risk of atherosclerotic vascular disease in HIV patients. “I think the publication [in Lancet HIV] as well as this poster suggest that on the venous side of things there may also be an accentuated risk,” said Dr. Reiss.

Heidi Crane, MD, a professor of medicine at the University of Washington, Seattle, presented a poster examining the underlying factors that may predispose HIV patients to first-time VTE events. Her team performed an adjudicated review of VTE cases among HIV patients at six institutions and found that the risk factors appeared to be distinct from those seen in the general population.

The traditional long plane ride was less common in this population, while factors such as injected drug use and pneumonia were more common. The VTE events occurred at a median age of 49 years; 30% of the patients had a detectable viral load. “We’re seeing a little more (VTE) than you might expect, and in a younger population than you might have guessed,” said Dr. Crane in an interview.

The most frequent predisposing risk factors were recent hospitalization (40%), infection (40%), or immobilization/bed rest (24%) within the past 90 days, and injectable drug use (22%). “It’s not just the traditional risk factors. Some HIV-specific risk factors are driving this,” said Dr. Crane.

She also aims to learn more about the specifics of risk factors, such as catheter-associated thromboses. The team is working to increase the sample size in order to parse out the relationships with specific outcomes.

In the meantime, the data further characterize the health challenges facing people living with HIV. “This is another example demonstrating that comorbid conditions among patients with HIV that are often considered age related occur at much younger ages in our population,” said Dr. Crane.

SOURCE: Rokx C et al. CROI 2019, Abstract 636; and Tenforde MW et al. CROI 2019, Abstract 637.

.