[Duration of anticoagulant therapy in venous thromboembolic complications]

Adequate anticoagulant therapy is a general approach to treatment of deep vein thrombosis. However, the duration of anticoagulant therapy is not strictly specified in everyday clinical practice. The present article deals with various approaches to selecting the duration of therapy with anticoagulants based on the findings of studies, national and foreign clinical guidelines. The minimal duration of therapy for deep vein thrombosis and pulmonary thromboembolism amounts to 3 months in accordance with the national and American recommendations. For some cohorts of patients, continuation of therapy above 3 months is considered: patients with idiopathic thrombosis (the recommended duration of therapy of not less than 6 months), patients having persisting risk factor for relapse of thrombosis on termination of the main therapeutic course, oncological patients (6 month therapy followed by assessing the risk and benefit of continuing therapy with anticoagulants). Prolonged therapy of venous thromboembolism using unfractionated heparin or low-molecular-weight heparin followed by changing over to vitamin K antagonists is associated with decreased risk for thrombosis relapse approximately by 90%, however increasing the risk of haemorrhage. Currently, as an alternative, it is possible to consider administration of novel oral anticoagulants (rivaroxaban, dabigatran, apixaban) which beside high efficacy are associated with less risk of bleeding. The route of administration, no necessity to control the INR, and the minimal number of drug and food interactions make administration of new oral anticoagulants an attractive alternative to therapy with heparins and vitamin K antagonists.