Ten-Year Survival after Coronary Bypass Surgery for Unstable Angina

We have assessed the long-term results of coronary bypass surgery performed for unstable angina in 1282 patients from 1970 to 1982. The operative mortality was 1.8 per cent; in the first 4 years it was 2.5 per cent, and in the last 8 1/2 years it was 1.7 per cent. Using actuarial techniques, we determined that the 5-year and 10-year survival rates (mean ±S.E.) were 92±1 per cent and 83±2 per cent, respectively, for the whole group. For patients with “normal” left ventricular function, they were 92±2 per cent and 86±3 per cent, and for patients with “abnormal” left ventricular function 91±2 per cent and 79±4 per cent (P = 0.14). No significant differences were observed in the long-term survival for any of the three clinical subgroups of patients with unstable angina — angina at rest, angina after recovery from acute myocardial infarction, and progressive angina of recent onset (P = 0.49). The reoperation rates at 5 and 10 years were 6±1 per cent and 17±3 per cent. Currently, 61 per cent of the survivors have no angina; angina occurs on severe exertion in 20 per cent, on ordinary exertion in 14 per cent, and on mild exertion in 5 per cent. We conclude that coronary bypass surgery is an effective form of therapy (for up to 10 years) in patients with unstable angina. (N Engl J Med. 1983; 308:676–81.).