The Journal of Thoracic and Cardiovascular Surgery, Vol 73, 165-175, Copyright © 1977 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
The impact of coronary artery bypass on late myocardial infarction
DJ Ullyot, J Wisneski, RW Sullivan, EW Gertz and C Ryan
Two hundred consecutive patients undergoing coronary artery bypass for
stable and unstable angina pectoris were followed clinically 3 to 53 months
(mean 27) and with serial electrocardiograms (ECG's) 3 to 43 months (mean
18.5) postoperatively. Complete (twelve lead) resting ECG data including
preoperative, early postoperative (in hospital), and late (post hospital)
studies were available in 98 per cent (196/199) of hospital survivors. A
total of 2,304 ECG's were examined by two cardiologists for a total
follow-up of 3,629 patient months. Myocardial infarction was defined as the
appearance of a new, significant (Minnesota Code) Q wave. Fifty-four per
cent (108/200) had triple vessel disease and 24 per cent (47/200)
preinfarction angina pectoris by strict criteria. There was one hospital
death for an operative mortality of 0.5 per cent (1/200). There was one
late fatal and three late nonfatal myocardial infarctions. Seventeen
patients developed new Q waves in the early postoperative period, a
perioperative infarction rate of 8.5 per cent (17/200). The 43 month
cumulative myocardial infarction rate, including all early and late
postoperative new Q waves and three late deaths from cardiac disease, was
14 per cent. Twenty-two per cent (20/91) showed disappearance of Q waves
present at the time of hospital discharge. These data suggest that the late
myocardial infarction rate is low in surgically managed patients.
