Surgical treatment for stable angina pectoris. Prospective randomized study.

To evaluate the role of coronary bypass treatment of stable angina, 72 patients were randomly divided into surgical and medical groups. They were followed with treadmill tests and repeat catheterization. Anginal symptoms decreased or disappeared in 89 per cent of those operated on and 65 per cent of those not operated on, but more of the former than of the latter became asymptomatic: 69 vs. 11 per cent respectively (p smaller than 0.01). Exercise tolerance time improved significantly (p smaller than 0.001) in both groups, but more in the group operated on, plus 78 per cent vs. plus 48 per cent, p smaller than 0.05. During a 28-month follow-up period, fewer cardiac complications occurred in the patients operated on--14 vs. 34 (p smaller than 0.02). Mortality was 9 per cent in the patients operated on and 14 per cent in those not operated on; this difference is not significant. The results indicate that improvement, though demonstrable in both groups, is greater with surgery, and quality of life during the first 28 months is better in patients who are operated on.