Affiliation:
1. University of Washington School of Pharmacy, Anticoagulation Services, University of Washington Medical Center, Seattle,
Abstract
Patients with hypercoagulable conditions, including malignancy, are at increased risk of recurrent venous thromboembolic events (VTE). The general approach to treatment and prevention of VTE in patients with thrombophilia is similar to that of patients who present with VTE associated with transient risk factors, including immobility, trauma, and surgery. However, several important issues must be considered in the initial management of acute VTE, in the long-term prevention of VTE following an initial event, and in VTE prophylaxis in patients with hypercoagulable conditions. Patients with antithrombin deficiency are prone to heparin resistance and may require concurrent antithrombin concentrates or anticoagulation with direct thrombin inhibitors for adequate treatment of acute VTE. In patients with malignancy, low-molecular-weight heparins have been found to be more effective than unfractionated heparin for the initial treatment of VTE. Long-term prevention is preferred for most patients with hypercoagulable conditions, and the latest trials show that low-intensity warfarin is not as effective as typical moderate-intensity therapy for chronic therapy. Primary prophylaxis of asymptomatic carriers is not warranted unless they are exposed to additional risk factors, including surgery, trauma, immobilization, and pregnancy. Prolonged prophylaxis may be appropriate in patients with malignancy who undergo surgical procedures.