Ischemic heart diseases continue to be leading causes of death throughout the world. Blood platelets play a pivotal role not only in haemostasis but also in the pathogenesis of thrombosis and atherosclerosis, platelet aggregation being an essential step in the formation of either an effective haemostatic plug or an intravascular thrombus. The benefits of various antiplatelet therapies ranging from aspirin, ticlopidine, Clopidogrel, and intravenous platelet GPIIb/IIIa antagonists in various thromboembolic disorders are well documented. The studies of CAPRIE, CURE, PCI-CURE and MATCH have shown that the clopidogrel has a highly advantageous preventive effect in the ischaemic vascular diseases, that is why clopidogrel be highly recommended in the stroke prevention.