Provoked versus unprovoked venous thromboembolism: Findings from GARFIELD-VTE.

INTRODUCTION: Venous thromboembolism (VTE) has a long-term risk of recurrence, dependent on the presence or absence of provoking risk factors at the time of the event. OBJECTIVE: To compare clinical characteristics, anticoagulant patterns, and 12-month outcomes in patients with transient provoking factors, active cancer, and unprovoked VTE. METHODS: The Global Anticoagulant Registry in the FIELD (GARFIELD)-VTE is a prospective, observational study that enrolled 10 207 patients with objectively diagnosed VTE from 415 sites in 28 countries. RESULTS: Patients with transient provoking factors were younger (53.0 years) and more frequently women (61.2%) than patients with unprovoked VTE (60.3 years; 43.0% women) or active cancer (63.6 years; 51.7% women). After 6 months, 59.1% of patients with transient provoking factors remained on anticoagulation, compared to 71.3% with unprovoked VTE and 47.3% with active cancer. At 12 months, this decreased to 36.7%, 51.5%, and 25.4%, respectively. The risk of mortality (hazard ratio [HR], 1.21; 95% confidence interval [CI], 0.90-1.62), recurrent VTE (HR, 0.84; 95% CI, 0.62-1.14), and major bleeding (HR, 1.26; 95% CI, 0.86-1.85) was comparable in patients with transient provoking factors and unprovoked VTE. Patients with minor and major transient provoking factors had a similar risk of recurrent VTE (HR, 0.99; 95% CI, 0.59-1.66), but those with major transient risk factors had a lower risk of death (HR, 0.61; 95% CI, 0.38-0.98). CONCLUSION: At 1 year, nearly 40% of patients with transient provoking factors and slightly over half of patients with unprovoked VTE were on anticoagulant treatment. Event rates were comparable between the two groups. Risk of death was higher in patients with minor transient factors than in those with major transient factors.

Upper Extremity DVT versus Lower Extremity DVT: Perspectives from the GARFIELD-VTE Registry.

Upper extremity deep vein thrombosis (UEDVT) is less common than lower extremity DVT (LEDVT) and consequently less well characterized. This study compared clinical characteristics and 1-year outcomes between 438 UEDVT patients and 7,602 LEDVT patients recruited in the GARFIELD-VTE registry. UEDVT patients were significantly more likely to have a central venous catheter than those with LEDVT (11.5% vs. 0.5%; p < 0.0001), and had a higher rate of active cancer (16.2%) or recent hospitalization (19.4%) compared with LEDVT patients (8.7% and 11.2%, respectively). Nearly all patients with UEDVT and LEDVT were initiated on anticoagulant therapy, which was a direct oral anticoagulant in one-third individuals in both groups. At 3, 6, and 12 months, the proportion of UEDVT and LEDVT patients who were receiving anticoagulant therapy was 82.6 and 87.4%, 66.0 and 72.6%, and 45.7 and 54.6%, respectively. In the UEDVT and LEDVT groups, VTE recurrence rate was 4.0 (95% confidence interval [CI], 2.4-6.7) and 5.5 (95% CI, 4.9-6.1) per 100 person-years, respectively; major bleed was noted in 1.3 (95% CI, 0.6-3.2) and 1.6 (95% CI, 1.3-1.9) per 100 person-years and all-cause mortality in 9.7 (95% CI, 7.1-13.4) and 6.7 (95% CI, 6.1-7.3) per 100 person-years, respectively. Hence, risk of recurrence was similar in the two groups whereas all-cause mortality was significantly higher in the UEDVT group than the LEDVT group (p = 0.0338). This latter finding was likely due to the high prevalence of cancer in the UEDVT group.

Anticoagulation therapy patterns for acute treatment of venous thromboembolism in GARFIELD-VTE patients.

BACKGROUND: Parenteral anticoagulants and vitamin K antagonists (VKAs) have constituted the cornerstone of venous thromboembolism (VTE) treatment. Meanwhile, direct oral anticoagulants (DOACs) provide physicians with an alternative. The Global Anticoagulant Registry in the FIELD (GARFIELD)-VTE observes real-world treatment practices. OBJECTIVES: Describe initial anticoagulation (AC) treatment patterns in VTE patients who received parenteral AC, VKAs, and/or DOACs within ±30 days of diagnosis. METHODS: VTE patients were categorized into parenteral AC only, parenteral AC with transition to VKA, VKA only, parenteral AC with transition to DOAC, and DOAC only. RESULTS: A total of 9647 patients were initiated on AC treatment alone. 4781 (49.6%) patients received DOACs ± parenteral ACs; 3187 (33.0%), VKA ± parenteral ACs; and 1679 (17.4%) parenteral ACs alone. Rivaroxaban was the most frequently used DOAC (79.4%). DOACs were more frequently used in North America/Australia (58.1%), Europe (52.2%), and Asia (47.6%) than in Latin America (29.7%) and the Middle East/South Africa (32.5%). In patients with suspected VTE, most received parenteral AC monotherapy (67.7%). Patients with deep vein thrombosis were more likely to receive DOACs alone than those with pulmonary embolism with or without deep vein thrombosis (36.2% vs 25.9%). Active cancer patients received parenteral AC alone (58.9%), with 25.5% receiving DOAC ± parenteral AC and 12.8% parenteral AC and VKA. A total of 46.5% of pregnant patients received parenteral AC monotherapy, 34.0% were treated with VKA ± parenteral AC, and 19.5% received a DOAC (± parenteral AC). CONCLUSION: AC treatment patterns vary by patient population, geographic region and site of VTE. Guidelines for AC therapy are not always adhered to.

Practical viewpoints on the diagnosis and management of heparin-induced thrombocytopenia.

Heparin-induced thrombocytopenia (HIT, type II) is an immune-mediated disorder due to antibodies formed against heparin-platelet factor 4 complexes, usually appearing at days 5 to 14 after initiation of heparin. It is important to recognize HIT because heparin prophylaxis or treatment paradoxically associates with new venous and/or arterial thrombosis. Early clinical suspicion and diagnosis together with proper pharmacotherapy and close laboratory monitoring are the cornerstones for successful management. This includes monitoring of Thrombocytopenia, its Timing to heparin administration, appearance of new Thrombosis or resistance to treatment, and differential diagnosis by exclusion of o Ther causes (the 4T's). Specific attention should be paid to the absence or presence of thrombosis and to tailoring thromboprophylaxis or anticoagulant therapy with a nonheparin alternative. Even in the absence of HIT-associated thrombosis, an active policy for prolonged thromboprophylaxis is demanded. Rapid and reliable assays should be developed for diagnosis and anticoagulation monitoring to secure safe management with nonheparins. Semiquantitative testing for on-call hours should be available and later confirmed as clinically needed. Alternative therapeutic options are available, but because their use is infrequent, experienced coagulation treatment centers should provide guidance in the treatment and in laboratory monitoring. Most of the evidence in HIT is grade IC, and thus the best evidence is provided by clinical experience. New anticoagulants and platelet inhibitors may offer future alternatives in the management of HIT, but the current treatment options provide the best experience and benefit. The joint clinical and laboratory guidelines provided in this article along with two practical case scenarios were prepared by a Nordic expert panel. They will be valuable for hematologists and colleagues who do not routinely encounter HIT.