Perioperative Myocardial Infarction after Coronary Artery Bypass Grafting: Detection by serial electrocardiograms and analysis of risk factors / 대한흉부외과학회지

ABSTRACT

The study in detection of perioperative myocardial infarction by serial ECGs and the analysis of risk factors involved was carried out from January 1994 to July 1996 on 87 consecutive patients undergoing coronary artery bypass grafting. There were significant differences in the mean CK-MB peaks and frequencies of flipping in LDH1/LDH2 among the 3 groups (group I new Q-wave, group II S-T change, group III no ECG change). The ECG was considered positive for postoperative myocardial infarction if the new Q-waves appeared in the postoperative period or if S-T segment changes persisted for more than 48 hours. The hospital mortality rate was 3.3% and the perioperative infarction rate was 17.2%. The following risk factors of the perioperative MI were found endarterectomy, decreased ejection fraction (< or =40%) and prolonged aortic cross clamping time. Left main disease, triple vessel disease, 3 or more graft, unstable angina and hypertension did not correlate with myocardial infarction. This study suggests that serial ECGs could be used as means of detecting the perioperative myocardial infarction after coronary artery bypass grafting.