Angina pectoris, one to 10 years after aortocoronary bypass surgery.

The incidence of angina pectoris (AP) after bypass surgery was assessed in 1041 patients operated on consecutively between 1971 and 1980. Of the 977 survivors, 920 (94%) participated in the study with a followup time varying from 1 to 10 years (mean 3.5 years). Post-operative angina pectoris was present at 1 year in 277 patients (30%), at 3 years in 46%, at 8 years in 50%. The pain limited usual physical activities in 17.5%, 30% and 25%, respectively at these times. Nonetheless, 89% of the respondents felt improved by surgery. Factors without predictive value for late outcome were sex, number of pre-operative diseased vessels, and pre-operative ejection fraction. A correlation was found between post-operative AP and younger age at surgery in the males only (P less than 0.001); between AP and patency rate of the bypass graft (P less than 0.005) and with the status of the coronary arterial tree at three years post-operatively (P less than 0.001) in both sexes. The percentage of patients with recurrent AP increased with time after surgery up to 3 years, but remained stable thereafter. In conclusion, post-operative AP seems initially related to decreased functioning of the bypass graft, later to progression of coronary sclerosis in the native circulation.