Low recurrence rate after deep calf‐vein thrombosis with 6 weeks of oral anticoagulation

Astermark J, Björgell O, Lindén E, Lethagen S, Nilsson P, Berntorp E (University Hospital, Malmö, Sweden). Low recurrence rate after deep calf‐vein thrombosis with 6 weeks of oral anticoagulation. J Intern Med 1998; 244 : 79–82. Objectives To evaluate the recurrence rate after deep calf‐vein thrombosis treated with 6 weeks of oral anticoagulation. Design and subjects A 2 year follow‐up of 126 consecutive patients admitted to the Department of Internal Medicine with venographically verified deep calf‐vein thrombosis. Results One hundred and twenty‐six patients were treated with warfarin for 6 weeks, 18 of them having had a previous episode of venous thrombosis (DVT). Eleven patients (8.7%) suffered a recurrent thromboembolic episode within 2 years, four of which were within the first 3 months. Eight of those without a history of DVT had a recurrence (7.4%). Three of these were activated protein C (APC)‐resistant, one was protein C‐deficient and one had malignant melanoma. Eight patients (6.3%) reported minor haemorrhagic complications, but no major bleeding was seen. Conclusion Our data support the use of a 6 week regimen of secondary oral prophylaxis after a first episode of deep calf‐vein thrombosis in patients without a permanent risk factor. Whether individuals with inherited thrombophilia require prolonged treatment remains to be evaluated.