The influence of a low ejection fraction on long-term survival in systematic off-pump coronary artery bypass surgery

Objective: Poor left-ventricular ejection fraction (EF) is a recognized operative and long-term risk factor in coronary artery bypass surgery. Over the past decade, off-pump coronary artery bypass surgery has emerged as a new strategy to address myocardial revascularization in poor left-ventricular EF patients, but few reports have documented long-term results. The aim of this study was to investigate long-term clinical results in off-pump coronary artery bypass patients with ≤35% left-ventricular EF. Methods: From September 1996 to May 2006, 1250 patients underwent off-pump coronary artery bypass revascularization, and were prospectively followed-up at the Montreal Heart Institute. Among them, 137 patients (pts) had a preoperative left-ventricular EF ≤35%. Follow-up was completed in 97% of patients. Results: Mean follow-up was 66 ± 34 months. Rate of grafts per pts was comparable in both groups. Overall 30-day mortality was 1.7% (1.5% EF >35% pts vs 2.9% in EF ≤35% pts; p = 0.19). Ten-year survival was lower in poor EF patients (44 ± 7% vs 76 ± 2%), and remained significant even after adjusting for risk factors (p = 0.04). Freedom from cardiac death for both groups was also significantly reduced in poor EF patients (p = 0.008). After adjustment, freedom from the combined end point of cardiac or sudden death, myocardial infarction, repeat coronary revascularization, unstable angina, and cardiac failure was comparable in both groups (p = 0.5). Conclusions: Off-pump coronary artery bypass surgery can be performed adequately and safely in poor EF patients. However, overall and cardiac survival was decreased in this subset of patients with a comparable freedom from major cardiac adverse related events.