Recurrent venous thromboembolism: diagnosis and management

A diagnosis of recurrent venous thromboembolism is commonly suspected by physicians in the clinical setting. Many do not realize that recurrent venous thromboembolism may mimic the first venous thromboembolic event (VTE) and that only 20 to 30% of patients who have had a first VTE actually have objective recurrent thrombotic disease. Objective testing is necessary to prevent the misdiagnosis of thrombophilia in patients and the associated exposure to prolonged anticoagulant treatment that accompanies that diagnosis. In patients with clinically suspected recurrent venous thrombosis, compression ultrasonography in a new venous segment is the preferred diagnostic approach and contrast venography is an alternative test. There is insufficient evidence to know whether D-dimer testing is an effective approach to the diagnosis of thrombophilia. In patients with suspected recurrent pulmonary embolism, the diagnostic method should begin with ventilation/perfusion lung-imaging and a complementary pulmonary angiography when the results of initial tests are equivocal. Patients with recurrent venous thromboembolism should be treated with anticoagulants for longer than 6 months but the precise period depends on the patient’s risk of bleeding as a result of the treatment. Finally, there is currently a lack of evidence that risk for recurrent VTE is increased in patients with a first episode of venous thromboembolism and heterozygous factor V Leiden mutation or the G20210A prothrombin mutation.