Heparin in Patients with Venous Thromboembolism and Contraindications to Oral Anticoagulant Therapy

Abstract

After an initial course of heparin therapy, patients with venous thromboembolism require continuing anticoagulant therapy for several months after hospital discharge to prevent recurrences. For most patients oral anticoagulants are the treatment of choice. However, patients receiving therapy need to participate in frequent and careful laboratory monitoring, and a patient's inability or unwillingness to cooperate in such procedures should contraindicate the use of oral anticoagulants. Oral anticoagulants may also be contraindicated in patients with serious coexisting conditions. Finally, several authors consider that oral anticoagulants should not be administered to elderly people, and when administered to pregnant women, they may be associated with embryopathy.

Several trials have demonstrated that subcutaneous heparin may be an acceptable alternative to coumarin. However, the high doses required for continuing prophylaxis have raised concerns about the risks of development of osteoporosis and bone fractures. The recently developed low-molecular-weight heparins constitute a good alternative.

Keywords:

Venous thromboembolism - therapy - contraindications - heparin - oral anticoagulants