Predictors of reoperation after myocardial revascularization

The first 1,000 patients undergoing primary isolated myocardial revascularization each year from 1971 to 1978 were analyzed to define the incidence of reoperation and to elucidate the determinants of reoperation and reoperation-free survival. Six hundred sixty-six patients (9.7%) underwent reoperation in a mean of 6.9 +/- 3.2 years. Cumulative percent reoperation was 2.7% at 5 years, 11.4% at 10 years, and 17.3% at 12 years. The annual incidence of reoperation was 1.1% at 5 years and increased to 3.9% at 12 years. Twenty-five patient descriptors were analyzed for predictors of reoperation. Young age was found to be the most important predictor of potential for reoperation. Other risk factors in descending order of significance were absence of an internal mammary artery graft, incomplete revascularization, New York Heart Association Functional Class III/IV, and single or double vessel disease. Absence of an internal mammary artery graft was an important predictor for all age groups. In the multivariate analyses for risk factors for reoperation-free survival, absence of an internal mammary artery graft was the most important predictor. Other factors of major significance were smoking, incomplete revascularization, and moderate/severe left ventricular impairment. Internal mammary artery grafting neutralizes hypertension, serum cholesterol level higher than 300 mg/dl, and smoking as risk factors for reoperation-free survival.