In acute myocardial infarction the early patency of the infarct-related artery is positively correlated with improved left ventricular function and survival. Coronary artery reperfusion is commonly achieved by intravenous administration of thrombolytic agents. Methods of mechanical recanalization, mainly percutaneous transluminal coronary angioplasty (PTCA), have been proposed and tested as alternative or adjunctive ways to thrombolysis. Early coronary angiography provides reliable and irreplaceable information concerning mechanical intervention utility and feasibility. Therefore, it is incorporated in the mechanical revascularization strategies at various stages in the setting of acute myocardial infarction. In the primary, direct PTCA strategy early coronary arteriography is done for planning and carrying out mechanical revascularization as an alternative to intravenous thrombolytic therapy. This strategy may be particularly effective in patients presenting with cardiogenic shock, large infarctions, contraindications to thrombolytic therapy, and prior bypass surgery. Coronary angiography in evolving myocardial infarction has also been proposed to set the stage for rescue PTCA when thrombolysis has proved to be ineffective. Nevertheless, there are currently no unequivocal data to judge the value of the rescue PTCA strategy. After unsuccessful thrombolysis, this approach should be considered in patients with a large infarction, with cardiogenic shock, with left ventricular dysfunction and with refractory ischemia. Early, routine coronary angiography after lytic recanalization is not recommended. In fact, the strategy of immediate arteriography plus PTCA after thrombolytic therapy does not improve outcome but leads to several deleterious effects.