LOW RECURRENCE RATE AFTER DEEP CALF-VEIN THROMBOSIS WITH 6 WEEKS OF ORAL ANTICOAGULATION

Objectives. To evaluate the recurrence rate after deep calf-vein throm bosis treated with 6 weeks of oral anticoagulation. Design and subject s. A 2 year follow-up of 126 consecutive patients admitted to the Depa rtment of Internal Medicine with venographically verified deep calf-ve in thrombosis. Results. One hundred and twenty-six patients were treat ed with warfarin for 6 weeks, 18 of them having had a previous episode of venous thrombosis (DVT). Eleven patients (8.7%) suffered a recurre nt thromboembolic episode within 2 years, four of which were within th e first 3 months. Eight of those without a history of DVT had a recurr ence (7.4%). Three of these were activated protein C (APC)-resistant, one was protein C-deficient and one had malignant melanoma. Eight pati ents (6.3%) reported minor haemorrhagic complications, but no major bl eeding was seen. Conclusion. Our data support the use of a 6 week regi men of secondary oral prophylaxis after a first episode of deep calf-v ein thrombosis in patients without a permanent risk factor. Whether in dividuals with inherited thrombophilia require prolonged treatment rem ains to be evaluated.