Ischemic myocardial injury during coronary artery surgery

Abstract

ECG's and serum levels of SGOT, LDH, and CPK were examined during the postoperative period in 50 patients with angina pectoris who had myocardial revascularization procedures. ECG signs of acute myocardial infarction appeared in 34 per cent and changes compatible with acute ischemic injury were seen in 10 per cent. Elevation of SGOT exceeding 90 units occurred in 32 per cent of 50 patients, and LDH levels over 900 units occurred in 24 per cent. In patients with ECG evidence of post-operative infarction or ischemia, 50 per cent had abnormal SGOT levels and 55 per cent had abnormal LDH levels. In 16 patients with SGOT levels exceeding 90 units, 69 per cent had ECG evidence of acute infarction or ischemia. Two patients died following surgery and acute myocardial infarction was demonstrated in both at autopsy. Relief of angina occurred in one patient who developed a myocardial infarct following internal mammary implantation. A follow-up angiogram revealed no effective communication of the implant with myocardial vessels. Acute myocardial infarction is a frequent complication of coronary artery surgery as determined by serial ECG's. In this study, approximately 50 per cent of these patients had diagnostic elevations of SGOT or LDH.