Antiplatelet therapy in percutaneous coronary intervention

The goal of antiplatelet therapy for patients with acute coronary syndromes undergoing percutaneous coronary intervention (PCI) is to reduce the risk of ischaemic events without increasing the risk of bleeding. Aspirin, the most widely used anti-platelet agent, is effective, safe, and inexpensive and is recommended for all patients undergoing PCI. Clopidogrel, the thienopyridine agent, has been shown to reduce the rates of adverse cardiac events and mortality when given in a loading dose before PCI and in a maintenance dose thereafter. It has been extensively studied in patients with non–ST-elevation myocardial infarction (NSTEMI), but less so in patients with ST-elevation myocardial infarction (STEMI). Questions remain as to the optimal loading and maintenance doses of clopidogrel, timing of administration before PCI, and duration of therapy after placement of bare-metal or drug-eluting stents. New, more potent thienopyridines with faster onset of action are in development. Used with PCI, glycoprotein (GP) IIb/IIIa inhibitors reduce the rates of death, myocardial infarction, and urgent target-vessel revascularization in patients with STEMI and NSTEMI. Although GP IIb/IIIa inhibitors are most often used at the time of PCI, early administration in the emergency department or ambulance may improve clinical out-comes. All antiplatelet agents carry a risk of bleeding, which may significantly affect clinical outcomes.