What is the optimum duration of anticoagulation for the management of patients with idiopathic deep venous thrombosis and pulmonary embolism?

Abstract

Anticoagulant therapy is highly effective in preventing recurrent events in patients with venous thrombo-embolism (VTE). For patients with ‘secondary’ or ‘provoked’ VTE affecting isolated calf veins or upper limb, there is general agreement that six weeks to three months of anticoagulation is adequate. Those with ‘provoked’ iliofemoral deep vein thrombosis (DVT) or pulmonary embolism (PE) are usually treated for three or six months. The duration of treatment in patients with idiopathic VTE, however, is controversial. Some experts recommend long-term anticoagulation after the first episode of VTE, whereas others, including ourselves, advocate only three months of anticoagulation.