Exercise performance in patients with impaired left ventricular function following aorto coronary bypass

We studied 40 patients with preoperative ejection fraction (EF) of 0.35 or less who underwent aortocoronary bypass. An average of 3.1 saphenous vein grafts per patient were inserted and revascularization was considered complete in 33 (82%) of the subjects in the group. Mean follow-up period was 29 months (range 12-65 months). Early mortality was 5% (2 patients) and there were 7 late deaths (3 cardiac and 4 non-cardiac). The 5-year cardiac actuarial survival rate was 74 +/- 13% (+/- SEM). Angina has improved in 29 (94%) of the 31 long-term survivors with 23 (74%) being totally asymptomatic. Twenty-two of the long-term survivors performed an exercise test at the end of their follow-up period. These tests revealed that bypass surgery in such patients results in significantly enhanced myocardial oxygen consumption with concomitant increase in effort level and duration. The exercise ability is probably directly related to the degree of revascularization.