Management of venous thromboembolism: past, present, and future.

Venous thromboembolism, including deep vein thrombosis and pulmonary embolism, represents a significant source of morbidity and mortality in the United States and worldwide. The pharmacologic management of venous thromboembolic disease has witnessed significant advances since oral anticoagulant and heparin therapies began to gain widespread use more than 50 years ago. Cumulative clinical experience gained from using these 2 classes of antithrombotic agents for the prevention and treatment of venous thromboembolism in high-risk patients pointed to a number of efficacy and safety limitations. This prompted further research and the eventual introduction, in the 1980s, of low-molecular-weight heparin(s) as a potentially superior therapeutic modality. Within the last decade the pace of development of newer classes of antithrombotic agents for venous thromboembolism prevention and treatment (as well as other indications) has accelerated. Among agents at late stages of investigation are ximelagatran (a direct thrombin inhibitor), nematode anticoagulant peptide c2 (a tissue factor VIIa inhibitor), and sodium N-8(2-hydroxylbenzoyl)aminocaprylate (SNAC)/heparin (a heparin derivative). The most recently approved agents for venous thromboembolism indications include the heparinoid, danaparoid sodium, and the newly introduced selective factor Xa inhibitor, fondaparinux.