Duration of Anticoagulant Therapy in Venous Thromboembolism

In the past, there has been no agreement as to the desirable duration of oral anticoagulant therapy for patients after venous thromboembolism. A randomized trial, in which patients were treated for six weeks or six months after diagnosis, was established to clarify the situation. A total of 186 patients were studied. The results suggest that there is no benefit from oral anticoagulants administered for longer than six weeks, unless there is a past history of venous thromboembolism, a recurrent thrombotic tendency or a continuing predisposing cause. Adequate heparinization is of prime importance in the early management of these patients. Abrupt cessation of oral anticoagulant therapy did not increase the incidence of recurrent venous thromboembolism. Bleeding complications are minimized if careful control is observed, and if drug interactions are avoided when other therapy is required for patients on oral anticoagulant therapy.