Antiplatelet Therapy in Cardiovascular Disease

Platelet activation and aggregation is a critical mediator of thrombosis in atherosclerotic vascular disease, including myocardial infarction, stroke, and peripheral vascular disease. Cardiovascular disease is the leading cause of death in most regions of the world, and antiplatelet therapy is an essential part of the treatment of acute coronary syndromes and stable coronary artery disease. Drugs that inhibit platelet function block key receptors or signaling pathways involved in platelet activation at sites of vessel injury including the cyclooxygenase-thromboxane pathway (aspirin), ADP signaling (P2Y12 receptor antagonists), thrombin signaling (PAR-1 receptor antagonists), or aggregation such as the fibrinogen receptor integrin α2bβ3 (glycoprotein IIb/IIIa antagonists). Knowledge of the therapeutic application of these drugs is aided in many cases by large, randomized, placebo-controlled clinical trials that have established the efficacy and safety profile of these treatments. This chapter will review the role of platelets in cardiovascular disease, the pharmacology of antiplatelet drugs, and the clinical evidence that guides their use.