Advances in the pathogenesis and treatment of acute coronary syndromes.

The clinical entities of unstable angina, non-Q wave myocardial infarction, and Q wave myocardial infarction share the same pathogenesis and, because of this, are linked under the heading of acute coronary syndromes. Prompt reperfusion in the early phase of acute ST segment elevation myocardial infarction, with thrombolysis or percutaneous transluminal coronary angioplasty, now has an established place in the treatment of this condition. However, thrombolysis has been disappointing and may be harmful in the treatment of unstable angina and non-Q wave myocardial infarction. While traditional therapy with morphine, oxygen, nitrates, aspirin, heparin, and beta blockers may be indicated in the treatment of all types of acute coronary syndromes, recent studies have led to advances in the treatment of unstable angina/non-Q wave myocardial infarction patients. In these patients, enoxaparin (a low molecular weight heparin) and the platelet glycoprotein IIb/IIIa receptor antagonists may be particularly effective.