A prospective controlled study of the efficacy of short-term anticoagulation therapy in patients with deep vein thrombosis of the lower extremity

Abstract

Purpose: The long-term risk for recurrent deep venous thrombosis (DVT) and the incidence of post-thrombotic syndrome (PTS) after long-term anticoagulation (LTA) therapy have been widely debated. In this study, we compare the results of short-term anticoagulation therapy versus conventional LTA therapy in patients with DVT of the lower extremity. Methods: Baseline assessments of DVT symptoms and risk factors were recorded in 105 patients. Diagnosis was made using duplex ultrasound/venography. Patients were sequentially assigned to 1 of the following treatment protocols: (A) conventional LTA therapy, which included initial intravenous standard heparin followed by warfarin on days 3 to 5 and was continued for 3 months for patients without pulmonary embolism (PE); or (B) short-term therapy, which included the same heparin therapy followed by warfarin on days 2 to 3 and was continued for 6 weeks only. Clinical and duplex ultrasound follow-up was done at 6 weeks, 3 and 6 months, and every 6 months thereafter. Results: Risk factors, location of DVT, and mean age of the 2 groups were comparable. Mean follow-up was 59 months. There were 4 immediate major complications in patients of group A (4 of 54 [7%]; 2 PEs and 2 significant bleeds) and 3 in patients of group B (3 of 51 [6%]; 1 PE and 2 bleeds). On long-term follow-up, 18 of 43 (42%) patients in group A and 20 of 44 (46%) patients in group B had PTS. Similarly, 10 of 43 (23%) patients in group A and 9 of 44 (20%) patients in group B had 1 or more recurrent thromboembolic events (not statistically significant). A significant difference was demonstrated only in patients with cancer; LTA was favored in reducing recurrent DVT and PTS. Two other patients in group A had late significant complications secondary to warfarin (hemorrhage in 1 and coumadin necrosis in the other), with no complications in group B. The mean number of days of hospitalization were fewer for patients in group B (5 versus 8 days), which is mainly due to earlier initiation of warfarin therapy for group B. Conclusion: In this study of our local population, we observed that short-term anticoagulation therapy was as effective as LTA therapy and less costly for use in most patients. It may also carry less risk of long-term warfarin complications, such as bleeding or skin necrosis. (J Vasc Surg 1998;28:630-7.)