ABSTRACT
This chapter reviews the role of platelets in thrombosis and thrombolysis, the effect of platelets on fibrinolysis, and the effects of fibrinolysis on platelet function. Plasminogen activators have been established as useful for the restoration of vascular patency in a variety of cardiovascular disorders. The clinical problems of delay in restoration of patency, reocclusion, failure to achieve patency, and hemorrhage represent the principal limitations of thrombolytic therapy, and these are determined primarily by the undesirable molecular and cellular effects of fibrinolytic therapy. Thrombus formation may also be initiated by platelet activation; however, the inciting event is the development of an acute fissure in an atherosclerotic plaque, the induction of damage or dysfunction to the endothelium. Platelets are crucial for the formation of occlusive thrombi, particularly under conditions of high shear rate. Platelet-rich thrombi are less sensitive to thrombolysis than platelet-poor thrombi, and platelet-rich clots are ly sed faster than platelet-poor clots on addition of exogenous plasminogen activators.
