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The currently approved direct oral anticoagulants (DOACs) are increasingly used in clinical practice. Although serious bleeding risks are lower with DOACs than with vitamin K antagonists, bleeding remains the most frequent side effect. Andexanet alfa and idarucizumab are the currently approved specific reversal agents for oral factor (F)Xa inhibitors and dabigatran, respectively. Our prior guidance document was published in 2016, but with more information available on the utility and increased use of these reversal agents and other bleeding management strategies, we have updated this International Society on Thrombosis and Haemostasis guidance document on DOAC reversal. In this narrative review, we compare the mechanism of action of specific and nonspecific reversal agents, review the clinical data supporting their use, and provide guidance on when reversal is indicated. In addition, we briefly discuss the reversal of oral FXIa inhibitors, a new class of DOACs currently under clinical development., Competing Interests: Declaration of competing interests J.H.L.: Participation on Advisory or Steering Committees for Grifols, Octapharma, Takeda, and Werfen. J.R.S.: In-kind laboratory support from Diagnostica Stago. L.A.C.: L.A.C.’s research institution has received honoraria from Bayer, BMS-Pfizer Alliance, The Academy for Continued Advancement in Healthcare Education, Amag Pharmaceutical, LEO Pharma, Sanofi, Valeo Pharma, and Servier. L.A.C. holds a Tier 2 Research Chair from the University of Ottawa. J.M.C.: Participation on Scientific Advisory Boards and consulting for Abbott, Anthos, BMS, Pfizer, Roche, Sanofi, and Werfen; research funding from CSL Behring to the institution. J.D.: Serves on advisory committees for Pfizer, Sanofi, Leo Pharma, Bristol-Myers Squibb, and Janssen. E.L-L.: Lecture honoraria and advisory fees from Bayer AG, Boehringer Ingelheim, Bristol-Myers Squibb/Pfizer, Daiichi Sankyo, Portola, CSL Behring, Norgine, Roche, Leo, AstraZeneca, and Aspen; institutional research support from Bayer AG, Bristol-Myers Squibb/Pfizer, Daiichi Sankyo, Werfen, and CSL Behring. B.R.: Consultant for AbocaSRL on medical devices; Advisory Committee for Bayer AG. C.M.S.: Advisory for Norgine Pharma. D.S.: Honoraria for educational presentations and advisory fees paid indirectly to research institute from AstraZeneca, BMS-Pfizer, Roche, Servier. D.S. is supported by a Tier 2 Canada Research Chair in Anticoagulant Management of Cardiovascular Disease. J.I.W.: Consultant or member of Advisory Boards or Steering Committees for Anthos, Bayer, Boehringer Ingelheim, Bristol-Myers Squibb, Daiichi Sankyo, Johnson and Johnson, Merck, and Regeneron., (Copyright © 2024 International Society on Thrombosis and Haemostasis. Published by Elsevier Inc. All rights reserved.)

Background: Venous thromboembolism (VTE) is a major preventable cause of morbidity, disability, and mortality in subjects with cancer. A global appraisal of cancer-associated VTE education and awareness is not available., Objectives: To evaluate VTE-related education, awareness, and unmet needs from the perspective of people living with cancer using a quantitative and qualitative approach., Methods: This cross-sectional study used data from an online-based survey covering multidimensional domains of cancer-associated VTE. Data are presented descriptively. Potential differences across participant subgroups were explored., Results: Among 2262 patients with cancer from 42 countries worldwide, 55.3% received no VTE education throughout their cancer journey, and an additional 8.2% received education at the time of VTE diagnosis only, leading to 63.5% receiving no or inappropriately delayed education. When education was delivered, only 67.8% received instructions to seek medical attention in case of VTE suspicion, and 36.9% reported scarce understanding. One-third of participants (32.4%) felt psychologically distressed when becoming aware of the potential risks and implications connected with cancer-associated VTE. Most responders (78.8%) deemed VTE awareness highly relevant, but almost half expressed concerns about the quality of education received. While overall consistent, findings in selected survey domains appeared to numerically differ across age group, ethnicity, continent of residence, educational level, metastatic status, and VTE history., Conclusion: This study involving a large and diverse population of individuals living with cancer identifies important unmet needs in VTE-related education, awareness, and support across healthcare systems globally. These findings unveil multilevel opportunities to expedite patient-centered care in cancer-associated VTE prevention and management., Competing Interests: Declaration of competing interests N.P. reports a training fellowship from the International Society on Thrombosis and Haemostasis and research funding from International Network of VENous Thromboembolism Clinical Research Networks (INVENT) outside of the submitted work. I.M. reports research funding from Leo Pharma and BMS-Pfizer outside of the submitted work, and advisory board/honoraria from Bayer, BMS-Pfizer, Leo, and Sanofi. P.A. reports research funding from Novo Nordisk, Sanofi, and Spark Therapeutics outside of the submitted work. G.C.M. reports personal fees from Bayer and BMS-Pfizer outside the submitted work. N.V.E. received, outside of the submitted work, advisory board honoraria from Daiichi-Sankyo, Bayer, and Leo Pharma paid to his institution. A.L. reports lecture fees from Leo Pharma outside the submitted work. E.O. reports funding from Novo Nordisk outside the submitted work and Pfizer advisory board/honoraria. F.N.A. reports grant funding (IIS paid to university) from Daiichi-Sankyo, Leo Pharma, Sanofi, and Actelion, and consultancy for Boston Scientific, outside of the submitted work. H.C.O. received a training fellowship from the International Society on Thrombosis and Haemostasis. D.M. reports speaker fees from Leo Pharma, BMS, and Pfizer. C.A. reports personal fees from Bayer, BMS/Pfizer, Daiichi-Sankyo, and Sanofi outside the submitted work. L.A.C. reports that her research institution has received honoraria from Bayer, BMS-Pfizer Alliance, The Academy for Continued Advancement in Healthcare Education, Amag Pharmaceutical, Leo Pharma, Sanofi, Valeo Pharma, and Servier. S.B. received consultancy and speaker fees from Bayer, Concept Medical, Boston Scientific, and Inari outside of the submitted work. M.D.N. reports personal fees from Bayer, Daiichi-Sankyo, BMS-Pfizer, Leo Pharma, and Viatris outside the submitted work. The remaining authors report no relevant conflicts of interest to disclose., (Copyright © 2024 International Society on Thrombosis and Haemostasis. Published by Elsevier Inc. All rights reserved.)

Background: There are no clinical trials with a head-to-head comparison between the 2 most commonly used oral anticoagulants (apixaban and rivaroxaban) in patients with atrial fibrillation (AF). The comparative efficacy and safety between these drugs remain unclear, especially in older patients who are at the highest risk for stroke and bleeding., Objective: The purpose of this study was to compare the risk of major bleeding and thromboembolic events between apixaban and rivaroxaban in older patients with AF., Methods: We conducted a population-based retrospective cohort study of all adult patients (66 years or older) with AF in Ontario, Canada, who were treated with apixaban or rivaroxaban between April 1, 2011, and March 31, 2020. The primary safety outcome was major bleeding, and the primary efficacy outcome was thromboembolic events. Secondary outcomes included any bleeding. Rates and hazard ratios (HRs) were adjusted for baseline comorbidities with inverse probability of treatment weighting., Results: This study included 42,617 patients with AF treated with apixaban and 30,725 patients treated with rivaroxaban. After inverse probability of treatment weighting using the propensity score, patients in the apixaban and rivaroxaban groups were well balanced for baseline values of demographic characteristics, comorbidities, and medications; both groups had a similar mean age of 77.4 years, and 49.9% were female. At 1 year, the apixaban group had a lower risk for both major bleeding with an absolute risk reduction at 1 year of 1.1% (2.1% vs 3.2%; HR 0.65; 95% confidence interval [CI] 0.59-0.71]) and any bleeding (8.1% vs 10.9%; HR 0.73; 95% CI 0.69-0.77), with no difference in the risk for thromboembolic events (2.2% vs 2.2%; HR 1.02; 95% CI 0.92-1.13)., Conclusion: In patients with AF, 66 years or older, treatment with apixaban was associated with lower risk for major bleeding, with no difference in the risk for thromboembolic events compared with rivaroxaban., Competing Interests: Disclosures Dr Shurrab is supported by a Research Chair in Cardiovascular Health, Health Sciences North Research Institute, Sudbury, Ontario. Dr Tu is supported by the Chair in Family and Community Medicine Research in Primary Care at UHN Department of Family and Community Medicine and receives a Research Scholar Award from the Department of Family and Community Medicine at the University of Toronto. Dr Turakhia has received research grants from Bristol Myers Squibb, American Heart Association, Bayer, Gilead Sciences, and the Food and Drug Administration and consulting fees from Medtronic, Pfizer, Johnson & Johnson, and AliveCor. He owns equity in iRhythm, Connect America, Forward, Evidently, and PocketRN. Dr Turakhia is an employee of iRhythm Technologies Inc., which manufactures ambulatory electrocardiogram monitors, but this work was not supported by the company and was performed exclusively in his academic role. Dr Lopes has received research grants or contracts from Amgen, Bristol Myers Squibb, GlaxoSmithKline, Medtronic, Pfizer, and Sanofi-Aventis as well as funding for educational activities or lectures from Pfizer, Bristol Myers Squibb, Novo Nordisk, and AstraZeneca and funding for consulting from Bayer, Boehringer Ingelheim, Bristol Myers Squibb, Novo Nordisk, and AstraZeneca. Dr Castellucci’s research institution has received honoraria from Bayer, Bristol Myers Squibb–Pfizer Alliance, the ACADEMY for Continued Advancement in Healthcare Education, Amag Pharmaceutical, LEO Pharma, Sanofi, Valeo Pharma, and Servier. Dr Ko is supported by the Jack Tu Chair in Cardiovascular Outcomes Research, Sunnybrook Hospital, and the University of Toronto. The remaining authors have nothing to disclose., (Copyright © 2024 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background: Data on availability, affordability, and accessibility is key for the planning of global strategies to reduce the burden of venous thromboembolism (VTE)., Objectives: A survey was conducted for the 10th anniversary of World Thrombosis Day to assess the availability of VTE therapies worldwide and challenges in uniform implementation., Methods: We gathered information on the approval status, availability, utilization, occurrence of shortages, and spread of medical and interventional therapies for VTE. Furthermore, we collected information by accessing or contacting national or continental medicines agencies, manufacturers or distributors, and online drug repositories., Results: We obtained data from a total of 69 countries: 33 countries in Europe, 19 in Asia, 7 in the Americas, 9 in Africa, and 1 in Oceania. Unfractionated heparin, low-molecular-weight heparin, and vitamin K antagonists were available in almost all countries, but shortages were recorded in 13%, 19%, and 15% of them, respectively. Direct oral anticoagulants were available in approximately three-quarters of the surveyed countries. At least one parenteral medication for heparin-induced thrombocytopenia was available in 57% of countries and a shortage was reported in 9% of these. Shortage of thrombolytics was recorded in 50% of countries. Overall, at least one type of catheter-directed therapy system was approved for use in 77% of countries and available in 23% of surveyed institutions. Our findings revealed notable geographic disparities in the worldwide availability of VTE therapies, the access to which appeared to be limited by economic and geopolitical factors., Conclusion: We anticipate that this comprehensive information will play a pivotal role in highlighting the shortcomings of VTE therapies and the lack of homogeneous availability globally., Competing Interests: Declaration of competing interests C.A. received honoraria for lectures and participation in advisory boards from Bayer, BMS/Pfizer, Daiichi Sankyo, and Sanofi. L.A.C. research institution has received honoraria from Bayer, BMS-Pfizer Alliance, The Academy for Continued Advancement in Healthcare Education, Amag Pharmaceutical, LEO Pharma, Sanofi, Valeo Pharma, and Servier. L.A.C. holds a Tier 2 research Chair in Thrombosis and Anticoagulation Safety from the University of Ottawa. S.B. received institutional grants from Sanofi, Concept Medical, Bayer, Medtronic, Boston Scientific, Bard, Novartis, and Daiichi Sankyo and honoraria for advisory boards or lectures from Boston Scientific, Penumbra, Viatris, Bayer, Sanofi. S.A.M., R.M.F., G.C.M., E.V.D.P., M.D., M.C.G.E., L.H., P.S., C.M.S., and M.T.S. report no conflicts of interest., (Copyright © 2023 International Society on Thrombosis and Haemostasis. Published by Elsevier Inc. All rights reserved.)

Background: Patients hospitalized for COVID-19 are at high risk of thrombotic complications and organ failure, and often exhibit severe inflammation, which may contribute to hypercoagulability., Objectives: To determine whether patients hospitalized for COVID-19 experience differing frequencies of thrombotic and organ failure complications and derive variable benefits from therapeutic-dose heparin dependent on the extent of systemic inflammation and whether observed benefit from therapeutic-dose anticoagulation varies depending on the degree of systemic inflammation., Methods: We analyzed data from 1346 patients hospitalized for COVID-19 enrolled in the ATTACC and ACTIV-4a platforms who were randomized to therapeutic-dose heparin or usual care for whom levels of C-reactive protein (CRP) were reported at baseline., Results: Increased CRP was associated with worse patient outcomes, including a >98% posterior probability of increased organ support requirement, hospital length of stay, risk of 28-day mortality, and incidence of major thrombotic events or death (patients with CRP 40-100 mg/L or ≥100 mg/L compared to patients with CRP <40 mg/L). Patients with CRP 40 to 100 mg/L experienced the greatest degree of benefit from treatment with therapeutic doses of unfractionated or low molecular weight heparin compared with usual-care prophylactic doses. This was most significant for an increase in organ support-free days (odds ratio: 1.63; 95% confidence interval, 1.09-2.40; 97.9% posterior probability of beneficial effect), with trends toward benefit for other evaluated outcomes., Conclusion: Moderately ill patients hospitalized for COVID-19 with CRP between 40 mg/L and 100 mg/L derived the greatest benefit from treatment with therapeutic-dose heparin., (Crown Copyright © 2023 Published by Elsevier Inc. on behalf of International Society on Thrombosis and Haemostasis.)

Background: Acute kidney injury (AKI) in patients with COVID-19 is partly mediated by thromboinflammation. In noncritically ill patients with COVID-19, therapeutic-dose anticoagulation with heparin increased the probability of survival to hospital discharge with reduced use of cardiovascular or respiratory organ support., Objectives: We investigated whether therapeutic-dose heparin reduces the incidence of AKI or death in noncritically ill patients hospitalized for COVID-19., Methods: We report a prespecified secondary analysis of the ACTIV4a and ATTACC open-label, multiplatform randomized trial of therapeutic-dose heparin vs usual-care pharmacologic thromboprophylaxis on the incidence of severe AKI (≥2-fold increase in serum creatinine or initiation of kidney replacement therapy (KDIGO stage 2 or 3) or all-cause mortality in noncritically ill patients hospitalized for COVID-19. Bayesian statistical models were adjusted for age, sex, D-dimer, enrollment period, country, site, and platform., Results: Among 1922 enrolled, 23 were excluded due to pre-existing end stage kidney disease and 205 were missing baseline or follow-up creatinine measurements. Severe AKI or death occurred in 4.4% participants assigned to therapeutic-dose heparin and 5.5% assigned to thromboprophylaxis (adjusted relative risk [aRR]: 0.72; 95% credible interval (CrI): 0.47, 1.10); the posterior probability of superiority for therapeutic-dose heparin (relative risk < 1.0) was 93.6%. Therapeutic-dose heparin was associated with a 97.7% probability of superiority to reduce the composite of stage 3 AKI or death (3.1% vs 4.6%; aRR: 0.64; 95% CrI: 0.40, 0.99) compared to thromboprophylaxis., Conclusion: Therapeutic-dose heparin was associated with a high probability of superiority to reduce the incidence of in-hospital severe AKI or death in patients hospitalized for COVID-19., (© 2023 Published by Elsevier Inc. on behalf of International Society on Thrombosis and Haemostasis.)

Oral anticoagulation therapy has evolved beyond vitamin K antagonists to include oral direct thrombin inhibitors and factor Xa inhibitors. Collectively known as "direct oral anticoagulants," this class of medications represents the current standard of care for the prevention and treatment of common thrombotic disorders, including atrial fibrillation and venous thromboembolism. Medications that target factors XI/XIa and XII/XIIa are currently under investigation for several thrombotic and nonthrombotic conditions. Given that these emerging medications will likely have distinct risk-benefit profiles to the current direct oral anticoagulants, may have different routes of administration, and could be used for unique clinical conditions (e.g., hereditary angioedema), the International Society on Thrombosis and Haemostasis Subcommittee on Control of Anticoagulation assembled a writing group to make recommendations on the nomenclature of anticoagulant medications. With input from the broader thrombosis community, the writing group recommends that anticoagulant medications be described by the route of administration and specific targets (e.g., oral factor XIa inhibitor)., (Crown Copyright © 2023. Published by Elsevier Inc. All rights reserved.)

Direct oral anticoagulants (DOACs) account for most oral anticoagulant use. DOAC-associated bleeding events are commonly encountered in clinical practice and are associated with substantial morbidity and mortality. Both specific reversal agents and nonspecific hemostatic therapies, such as prothrombin complex concentrates, are used in the management of DOAC-associated bleeding. Measuring hemostatic efficacy and demonstrating a clinical impact from these therapies among studies of bleeding patients is challenging. Thrombin generation assays provide information on the total hemostatic potential of plasma, and have emerged as a promising modality to both measure the impact of DOACs on coagulation and to evaluate the effects of hemostatic therapies among patients with DOAC-associated bleeding. The mechanisms by which nonspecific hemostatic agents impact coagulation and thrombin generation in the context of DOAC therapy are unclear. As a result, we undertook a review of the literature using a systematic search strategy with the goal of summarizing the effects of DOACs on thrombin generation and the effects of both specific reversal agents and nonspecific hemostatic therapies on DOAC-altered thrombin generation parameters. We sought to identify clinical studies focusing on whether altered thrombin generation is associated with clinical bleeding and whether correction of altered thrombin generation parameters predicts improvements in clinical hemostasis. Lastly, we sought to outline future directions for the application of thrombin generation assays toward anticoagulation therapies and the question of anticoagulation reversal., Competing Interests: Declaration of competing interest J.R.S. has received research support in the form of in-kind contributions from Diagnostica Stago. L.A.C.’s research institute has received honoraria from Amag Pharmaceuticals, Bayer, BMS-Pfizer Alliance, the Academy, LEO Pharma, Sanofi, Servier, and Valeo. M.C. has received research funding from BMS, Leo Pharma, and Pfizer, as well as honoraria from Bayer, Sanofi, Servier, BMS, Leo Pharma, and Pfizer, with all payments made to his institution., (Copyright © 2022 International Society on Thrombosis and Haemostasis. Published by Elsevier Inc. All rights reserved.)

Background: Assessment of the case-fatality rate (CFR) of major bleeding on dual antiplatelet therapy (DAPT) may improve balancing risks and benefits of different durations of DAPT following percutaneous coronary intervention (PCI)., Objectives: To determine the CFR of major bleeding in patients on DAPT after PCI and to compare rates among different durations of DAPT., Methods: Medline, Embase, and CENTRAL were searched from inception to August 2021 for randomized trials that reported fatal bleeding among patients who were randomized to ≥1 month of DAPT following PCI. Summary estimates for CFRs of major bleeding were calculated using the random-effects inverse-variance method. Statistical heterogeneity was evaluated using the I 2 statistic., Results: Of 2777 citations obtained by the search, 15 (48%) of 31 potentially eligible studies were excluded because fatal bleeding was not reported, leaving 16 studies that were included in the analysis. Overall, there were 823 major bleeding events including 91 fatal events in 48,884 patients who were assigned to receive DAPT during study follow-up. The CFR of major bleeding was 10.8% (95% confidence interval [CI], 7.1-16.2; I 2  = 50%) in the entire study population, and 13.8% (95% CI, 6.5-27.1; I 2  = 28%), 11.2% (95% CI, 6.7-18.0; I 2  = 0%), and 5.8% (95% CI, 3.0-11.1; I 2  = 0%) in those on short-term (≤6 months; n  = 16,553), standard-term (12 months; n  = 19,453), and long-term DAPT (>12 months; n  = 10,238), respectively., Conclusion: Fatal bleeding is not reported in many studies evaluating DAPT after PCI. The CFR of major bleeding on DAPT is substantial and may be higher in the first 12 months of DAPT than during long-term DAPT., (© 2022 The Authors. Research and Practice in Thrombosis and Haemostasis published by Wiley Periodicals LLC on behalf of International Society on Thrombosis and Haemostasis (ISTH).)

Introduction: Venous thromboembolism (VTE) is a leading cause of cardiovascular morbidity and mortality. The majority of VTE events are hospital-associated. In 2008, the Epidemiologic International Day for the Evaluation of Patients at Risk for Venous Thromboembolism in the Acute Hospital Care Setting (ENDORSE) multinational cross-sectional study reported that only approximately 40% of medical patients at risk of VTE received adequate thromboprophylaxis., Methods: In our systematic review and meta-analysis, we aimed at providing updated figures concerning the use of thromboprophylaxis globally. We focused on: (a) the frequency of patients with an indication to thromboprophylaxis according with individual models; (b) the use of adequate thromboprophylaxis; and (c) reported contraindications to thromboprophylaxis. Observational nonrandomized studies or surveys focusing on medically ill patients were considered eligible., Results: After screening, we included 27 studies from 20 countries for a total of 137 288 patients. Overall, 50.5% (95% confidence interval [CI]: 41.9-59.1, I 2 99%) of patients had an indication to thromboprophylaxis: of these, 54.5% (95% CI: 46.2-62.6, I 2 99%) received adequate thromboprophylaxis. The use of adequate thromboprophylaxis was 66.8% in Europe (95% CI: 50.7-81.1, I 2 98%), 44.9% in Africa (95% CI: 31.8-58.4, I 2 96%), 37.6% in Asia (95% CI: 25.7-50.3, I 2 97%), 58.3% in South America (95% CI: 31.1-83.1, I 2 99%), and 68.6% in North America (95% CI: 64.9-72.6, I 2 96%). No major differences in adequate thromboprophylaxis use were found across risk assessment models. Bleeding, thrombocytopenia, and renal/hepatic failure were the most frequently reported contraindications to thromboprophylaxis., Conclusions: The use of anticoagulants for VTE prevention has been proven effective and safe, but thromboprophylaxis prescriptions are still unsatisfactory among hospitalized medically ill patients around the globe with marked geographical differences., (© 2021 The Authors. Journal of Thrombosis and Haemostasis published by Wiley Periodicals LLC on behalf of International Society on Thrombosis and Haemostasis.)

Introduction: Pulmonary embolism (PE) has not been accounted for as a cause of death contributing to cause-specific mortality in global reports., Methods: We analyzed global PE-related mortality by focusing on the latest year available for each member state in the World Health Organization (WHO) mortality database, which provides age-sex-specific aggregated mortality data transmitted by national authorities for each underlying cause of death. PE-related deaths were defined by International Classification of Diseases, Tenth Revision codes for acute PE or nonfatal manifestations of venous thromboembolism (VTE). The 2001 WHO standard population served for standardization., Results: We obtained data from 123 countries covering a total population of 2 602 561 422. Overall, 50 (40.6%) were European, 39 (31.7%) American, 13 (10.6%) Eastern Mediterranean, 13 (10.6%) Western Pacific, 3 (2.4%) Southeast Asian, and 2 (1.6%) African. Of 116 countries classifiable according to population income, 57 (49.1%) were high income, 42 (36.2%) upper-middle income, 14 (12.1%) lower-middle income, and 3 (2.6%) low income. A total of 18 726 382 deaths were recorded, of which 86 930 (0.46%) were attributed to PE. PE-related mortality rate increased with age in most countries. The reporting of PE-related deaths was heterogeneous, with an age-standardized mortality rate ranging from 0 to 24 deaths per 100 000 population-years. Income status only partially explained this heterogeneity., Conclusions: Reporting of PE-related mortality in official national vital registration was characterized by extreme heterogeneity across countries. These findings mandate enhanced efforts toward systematic and uniform coverage of PE-related mortality and provides a case for full recognition of PE and VTE as a primary cause of death., (© 2021 The Authors. Research and Practice in Thrombosis and Haemostasis published by Wiley Periodicals LLC on behalf of International Society on Thrombosis and Haemostasis (ISTH).)

Clinical research in venous thromboembolism (VTE) is hindered by variability in the collection and reporting of data and outcomes. A consistent data language facilitates efficiencies, leads to higher quality data, and permits between-study comparisons and evidence synthesis. The International Society on Thrombosis and Haemostasis (ISTH) launched an international task force of more than 50 researchers to develop common data elements for clinical research in venous thromboembolism. The project was organized in seven working groups, each focusing on a topic area: General Core Data Elements; Anticoagulation and Other Therapies; Chronic VTE and Functional Outcomes; Diagnosis of VTE; Malignancy; Perioperative; and Predictors of VTE. The groups met via teleconference to collaboratively identify key data elements and develop definitions and data standards that were structured in a project-specific taxonomy. A Steering Committee met by teleconference and in-person to determine the overall scope of the project and resolve questions arising from the working groups. ISTH held an open public comment period to enable broader stakeholder involvement and feedback. The common data elements were then refined by the working groups to create a set of 512 unique data elements that are publicly available at http://isth.breakthrough.healthcare. The ISTH VTE Common Data Elements are intended to be a living project with ongoing curation, future expansion, and adaptation to meet the needs of the thrombosis and hemostasis research community., (© 2020 International Society on Thrombosis and Haemostasis.)

After completing anticoagulation therapy for acute venous thromboembolism (VTE), patients with unprovoked VTE are at increased risk of recurrent thrombotic events. Recent studies suggest a risk of nearly 10% in the first year after stopping anticoagulants and 30% at 8 years. Therefore, it is important to consider extended anticoagulation for secondary prevention in these high-risk patients. While several oral anticoagulants are available for this purpose, there is limited information available regarding the optimal agent to minimize bleeding risks and maximize efficacy at VTE prevention. This review article summarizes the evidence available for Vitamin-K antagonists (VKAs) and direct oral anticoagulants (DOACs) for extended treatment of VTE. We also introduce the COVET trial, the first head-to-head comparison of VKAs to DOACs, rivaroxaban and apixaban, for extended management of unprovoked VTE.