A Comparison of Hirudin with Heparin in the Prevention of Restenosis after Coronary Angioplasty

Platelet aggregation, the generation of thrombin, and the release of growth factors at the site of angioplasty have all been implicated in the process of restenosis. 1 , 2 Consequently, anticoagulants, antiplatelet agents, and specific antithrombin agents have been considered for the prevention of restenosis. 3 Thrombin is the most potent platelet activator known, stimulating the production of platelet-derived growth factor and the secretion of prostacyclin, platelet-activating factor, and plasminogen-activator inhibitor. Thrombin has apparent mitogenic effects on lymphocytes and vascular smooth-muscle cells. 4 , 5 Hirudin, a 65-amino-acid compound originally extracted from the salivary gland of the leech, is a specific inhibitor of thrombin. The . . .