Coronary artery bypass grafting within thirty days of acute myocardial infarction: Early and late results in 406 patients

Abstract

Between 1981 and 1987, 1726 coronary artery bypass operations were performed by a single group of surgeons at a community hospital. Overall hospital mortality in this group was 2.4% (41/1726). Of these patients 406 were operated on within 30 days of an acute myocardial infarction. The hospital mortality rate in this group was 6.7% (27/406) versus 1.1% (14/1320) in patients operated on without evidence of recent acute myocardial infarction (p less than 0.0001). In these 406 patients, sex, location of acute myocardial infarction, type of infarction, coronary anatomy, presence of postinfarction angina, technique of myocardial preservation, and the time from infarction to operation were not associated with hospital mortality. Univariate and multivariate analyses showed that three factors were significantly associated with increased hospital death: poor ejection fraction, less than 30% (p less than 0.0001), preoperative shock (p = 0.0005), and age greater than 70 years (p = 0.004). Follow-up was 90% complete (365/406 patients) at a mean time of 35 +/- 21 months. Of these patients 80% (292/365) were in New York Heart Association functional class I, and 10% (36/365) were in functional class II. Of all patients 88% were alive at 3 years, and 84% were alive at 5 years after operation. Multivariate comparison of survival curves showed that ejection fraction less than 30% was associated with decreased survival (p = 0.0002), followed by age (p = 0.0009). Patients younger than 70 years with an ejection fraction greater than 30% and not in cardiogenic shock can be operated on at any time after acute myocardial infarction without increased risk. Long-term survival and freedom from symptoms can be expected in these patients.