Aortocoronary Artery Graft During Early and Late Phases of Acute Myocardial Infarction

Abstract

From April, 1968, to August, 1972, 30 patients received one to three emergency saphenous vein grafts during acute myocardial infarction. In all but 1 patient, acute myocardial infarction occurred while the patients were in the hospital awaiting coronary angiography or myocardial revascularization. The patients were divided into two groups: those in the early and those in the late phases of acute myocardial infarction, depending on the time interval between the onset of chest pain and operation. Twenty-four patients (early phase) received grafts within 10 hours after the onset of infarction, and 18 of these 24 patients underwent operation within 4 hours after infarction. Two patients included in this group sustained myocardial infarctions in the operating room during elective myocardial revascularization procedures; another patient was brought to the operating room following cardiac arrest and was supported by internal cardiac massage throughout the opening of the chest and cardiac cannulation. Six patients (late phase) received grafts from three to fourteen days after acute infarction because of postinfarction angina. Only 1 patient was in cardiogenic shock prior to operation. Two patients, both from the early phase group, died in the postoperative period; and 1 patient died seven months postoperatively from a noncardiac cause. Twenty-five of 27 surviving patients became asymptomatic, and 2 patients continue to have mild angina (Functional Class II). Sixteen patients with 24 grafts were restudied in the postoperative period, and 22 of the grafts were found to be patent. This experience suggests that early operative intervention in acute myocardial infarction by the saphenous vein graft technique is beneficial to the patient. The rationale of revascularization in the early phase of acute myocardial infarction is to minimize the area of muscle necrosis by increasing perfusion to the ischemic myocardium around the infarct.