Although global mortality in the year following myocardial infarction is about 10%, this figure varies from less than 1% to more than 50% in some very high risk cases. The principal objective of clinical evaluation during the acute phase is to establish a prognosis and propose a rational strategy for myocardial revascularisation (by bypass grafting or angioplasty) in patients with a poor prognosis. An essential feature of this evaluation is to reduce health care costs and hospital stay to a minimum. Coronary angiography is the only investigation which allows assessment of the coronary circulation and is probably the best method of evaluating global and regional left ventricular function, two essential prognostic factors: on the other hand, it does not provide information about the presence of residual ischaemia or persistent myocardial viability in the infarcted territory. Some very high risk patients should undergo systematic coronary angiography to determine the possibilities for myocardial revascularisation: early post-infarction angina, left ventricular failure, chronic angina, elderly but valid patients... The indications of coronary angiography should also extend to patients with non-Q wave infarction, to young patients with myocardial infarction on thrombolysed infarcts: results of coronary angiography should then be compared with those of standard exercise stress testing. It is only in other situations, concerning a minority of patients, in which two attitudes may be considered: the first, to perform coronary angiography very early (within 24-48 hours of admission) allowing early discharge from hospital of many cases, completed later by standard exercise stress testing: any revascularisation procedure is considered at that time and requires a second hospital admission. The second attitude consists in performing coronary angiography between the 7th and 10th day only if some paraclinical changes are present: exercise stress testing then has an essential role; to improve its negative predictive value for absence of long-term coronary events it should be associated with radionuclide investigation of myocardial perfusion (thallium, MIBI) or with an evaluation or residual myocardial viability (labelled fatty acids, cyclotron). This attitude also allows early identification of "good candidates" for myocardial revascularisation.