Therapeutical potential of direct thrombin inhibitors for atherosclerotic vascular disease

Adverse cardiovascular events are the consequence of a molecular chain reaction at the site of vulnerable plaques. Key players are platelets and coagulation factors that are activated following plaque rupture and often cause arterial obstruction. Thrombin, a plasma serine protease, plays a role in hemostasis of coagulation as well as in thrombosis and cell growth, leading to restenosis and atherosclerosis. Interesting and promising new molecules, the direct thrombin inhibitors, have been shown to be as effective as the combination of glycoprotein IIb-IIIa inhibitors and heparin for the prevention of arterial thrombosis. Until recently, direct thrombin inhibitors could be applied only parenterally; therefore, therapy was limited to hospitalized patients. As a result of recent drug development, orally active direct thrombin inhibitors are now available and have been evaluated for the long-term treatment of venous thrombosis and arterial fibrillation. Due to their specific pharmacodynamic characteristics by binding directly to thrombin--and thus inhibiting platelet aggregation and fibrin generation--these novel drugs may also have therapeutic potential for the treatment of atherothrombotic disease and its complications such as myocardial infarction, stroke or limb ischemia.