Emergency cardiac catheterization and angiography in patients have resulted in an appreciation of the pathogenesis of AMI and the efficacy of thrombolytic therapy. Simple reperfusion of the infarcted myocardium, however, does not necessarily guarantee myocardial salvage, and preliminary studies have been somewhat confusing as to its beneficial effects. Metabolic support of the ventricle during early reperfusion may enhance left ventricular performance. Although the potential effects of thrombolytic therapy are still unclear, the routine administration of these agents has resulted in more frequent performance of early coronary angiography, with the result that appropriate therapeutic decisions can be made immediately regarding medical treatment, coronary angioplasty, or complete myocardial revascularization. In fact, in prolonged chest pain syndromes, emergency angiography may play a very important role in establishing appropriate initial therapy early in the course of hospitalization, potentially lowering mortality, morbidity, and cost. These issues will be answered ultimately only by carefully designed long-term randomized trials.