Coronary artery bypass surgery in patients over age 70 years: Report from the milwaukee cardiovascular data registry

Abstract

Between 1972 and 1985, 674 coronary bypass patients ≥ 70 years (70% male, mean age 73 years) were among 10,622 patients with both catheterization and operative data entered into the Milwaukee Cardiovascular Data Registry. These ≥ 70 years patients were analyzed regarding the operative morbidity, the 30‐day operative mortality, and the operative mortality's relation to coronary artery disease and ventricular wall motion abnormalities. The operative mortality was not different for the 174 patients operated upon before and the 500 patients after 1980. A mean of 3.4 grafts were placed during surgery. The complications encountered included a 7.1 % perioperative infarction rate, a 4.2% incidence of cerebrovascular accident, a 3.6% incidence of reoperation for bleeding, a 2.4% incidence of renal failure, and a 2.1 % incidence of pulmonary embolism. The overall operative mortality was 7.4%. The extent of coronary artery disease was distributed among patients such that 8.4% had single‐, 28.0% had double‐, and 63.6% had triple‐vessel disease. The operative mortality as related to the extent of coronary artery disease was 5.2% for single‐, 8.9% for double‐, and 7.0% for triple‐vessel disease. The operative mortality was 6.7% with no and 7.9% with left ventricular wall motion abnormalities. The operative mortality was 1.9% with 1 segmental wall motion abnormality, and increased to 13.3% (p<0.05) with 4–6 segmental wall motion abnormalities. The operative mortality for single‐vessel disease was 5.4% with normal and 4.3% with abnormal wall motion; for double‐vessel disease it was 4.3% with normal and 13.2% with abnormal wall motion, (p<0.05); and, for triple‐vessel disease, 8.3% with normal and 6.0% with abnormal wall motion. Actuarial life‐table analysis indicated that the probability of surviving at least 7 years is 64.6≥3.6%. There was no difference in the survival at 4 years regardless of the extent of coronary disease. After 4 years, the difference in survival between single‐ and triple‐vessel disease became significant (single, 91 % versus triple, 78%; p<0.05). The probability of survival at 7 years was affected by the presence of wall motion abnormalities (normal, 73% versus abnormal, 56%, p<0.05). These data suggest that coronary bypass surgery when performed in patients ≥ 70 years has a significant operative mortality which is probably not related to the extent of coronary artery disease, but to the severity of left ventricular wall motion abnormalities. Surviving patients have a relatively good long‐term outlook which, nevertheless, is adversely affected by the extent of coronary disease, and the severity of left ventricular wall motion abnormalities.