Duration of anticoagulation after venous thrombosis

Venous thromboembolism (VTE) is a multicausal disease which tends to recur. Recurrence can be prevented by anticoagulant treatment albeit at the cost of bleeding. Deciding on the optimal duration of anticoagulation is based on balancing the risk of recurrence and of bleeding in case anticoagulation is continued. Patients with VTE provoked by a transient risk factor have a low risk of recurrence and stopping anticoagulation after 3 months is recommended because the risk of bleeding likely outweighs the risk of recurrence. In patients with unprovoked VTE recurrence is high and indefinite anticoagulation should be considered. However, the majority of these patients will not suffer recurrence but thus far safe identification of low or high patients risk is not possible. Despite considerable advances in the identification of new risk factors for (recurrent) VTE, predicting the risk of recurrence in an individual patient remains a challenge. Measuring D-Dimer as a global coagulation markers and the use of prediction models that integrate clinical characteristics and laboratory markers are the most promising approaches to improve risk assessment and to optimize the duration of anticoagulation. New oral anticoagulants have been studied for treatment of patients with VTE. However, more data on the bleeding risk during extended thromboprophylaxis are needed to decide which patients may indeed benefit from these novel agents.