Prospective randomized study of coronary artery bypass surgery in stable angina pectoris: a progress report on survival.

This progress report on the prospective randomized study of the effect of coronary bypass surgery on prognosis presents the results of a minimum follow-up of 4 years. Seven hundred sixty-eight patients were recruited; all were men younger than age 65 years who had mild-to-moderate angina pectoris, at least two-vessel disease, and good left ventricular function. Of these, 373 were randomized to medical treatment and 395 to surgical treatment. Although 83 "medical" patients subsequently underwent surgery and 27 "surgical" patients did not undergo surgery, these patients were not excluded from the analysis, and the group randomized to coronary bypass surgery was compared with the group randomized to medical treatment. The surgical treatment group showed significantly better survival than the medical treatment group in the total patient population (p less than 0.001), particularly among patients with three-vessel disease (p less than 0.001). Although the 24% higher survival among surgical patients with left main coronary artery disease failed to reach statistical significance, the trend is probably meaningful. No significant difference in survival between medical and surgical treatment groups was noted in patients with two-vessel disease.