Management of post-infarction angina

Post-infarction angina includes a syndrome of ischemic chest pain occurring either at rest or during minimal activity 24 hours or more following an acute MI. It develops in approximately 10 to 15 per cent of patients and is particularly common in non Q-wave infarcts involving the anterior myocardial wall. Post-infarction angina may result from ischemia either within the infarct zone or at a distance and frequently portends a poor long term prognosis. Platelet aggregation, coronary vasospasm, and thrombus formation at the site of a ruptured atherosclerotic plaque are each involved in its pathogenesis. The initial treatment of post-infarction angina includes identification and correction of factors that increase myocardial demand including congestive heart failure and arrhythmias. beta-Adrenergic blockers, calcium channel blockers, and nitrate preparations constitute the first line of medical therapy. The role of heparin is controversial, yet it continues to be used in clinical practice. Although thrombolytic agents are currently being investigated, early experience suggests that they may accelerate clinical stabilization and allow time for elective revascularization when required. Antiplatelet therapy with aspirin has proven benefit in the long term management of unstable angina. Patients unresponsive to medical therapy should be considered for intra-aortic balloon pump placement and early coronary angiography. Revascularization with either coronary angioplasty or coronary artery bypass grafting may then be performed as dictated by the overall clinical status, available facilities, and coronary anatomy.