Oral anticoagulation after a first episode of venous thromboembolism: how long? How strong?

A number of studies have been published in the last years which shed light on the optimal intensity and the optimal duration of oral anticoagulation in patients with venous thrombosis. Based on these studies it is now generally recommended to treat patients with venous thromboembolism at an INR ranging from 2.0 to 3.0. The optimal duration of anticoagulation mainly depends on the nature of the thrombotic event. In patients with a temporary prothrombotic risk factor such as surgery, immobilization or trauma a relatively short duration of oral anticoagulation (3-6 months) is generally recommended. Patients with idiopathic venous thromboembolism require a considerably longer duration of anticoagulation (6 months at least).