Reduction of infarct size is a concept limited in clinical practice by the long period elapsing before hospital admission. Most patients are admitted only after the critical period of 6 to 8 hours following infarction when it might be possible to save the ischaemic, but not yet necrotic myocardium. Nevertheless, patients with altered haemodynamics and, therefore, a disturbed myocardial balance between oxygen requirement and oxygen supply may benefit from optimum management of the haemodynamic situation. This is achieved primarily by manipulation of preload and afterload and by enhancement of the collateral circulation to the ischaemic myocardium. However, the effects of cardiac surgery are limited by the negative sequelae of late reperfusion 6 hours after coronary ligation. Intra-aortic balloon pumping can be used only in large cardiosurgical centres because most of the so-treated patients remain pump dependent. The described measures have improved the hospitalisation period in patients with acute myocardial infarction, but the further prognosis is dictated by the nature and extent of underlying coronary heart disease.