Surgery for impending myocardial infarction, acute evolving myocardial infarction, and complications of myocardial infarction.

Post-infarction ventricular aneurysm, ventricular septal defect, and mitral insufficiency are all potentially amenable to surgical intervention. In each instance the results of operation and the prognosis following operation depend largely on the extent of infarction, the status of the residual myocardium, and the interval between infarction and operation. When the residual myocardium exhibits good contractility, the results are usually good. When early operation is performed in the face of a deteriorating clinical course and with poorly contracting residual myocardium, the mortality rates are extremely high. In an effort to increase the efficiency of the residual myocardium, concomitant coronary bypass surgery should be performed whenever possible. In this difficult group, more recent supportive measures such as the intra-aortic balloon pump may be particularly helpful when utilized both before and after operation. The surgical indications and results of coronary bypass surgery in impending or acute evolving myocardial infarction are not as well defined, but it is evident that myocardial revascularization may be useful in carefully selected patients.