Revascularization among patients with severe left ventricular dysfunction: a meta-analysis of observational studies

Coronary artery bypass graft (CABG) surgery is the standard of care for the management of patients with severe three-vessel and left main coronary artery disease (CAD). However, the optimal strategy for management of patients with CAD and severe left ventricular (LV) dysfunction [ejection fraction (EF) ≤35%] is not clear. A meta-analysis of observational studies was performed to determine the operative mortality and long-term (5-year actuarial survival) outcomes among patients with severe LV dysfunction undergoing CABG.

A systematic computerized literature search was performed and observational studies consisting of patients undergoing isolated CABG for CAD and severe LV dysfunction were included. Studies that did not report operative mortality, long-term (≥1 year) survival data, or pre-operative EF and multiple studies from the same group were excluded. In total, 4119 patients from 26 observational clinical studies were included. The estimated mean age was 63.9 years and 82.4% of patients were men. The mean (estimate) pre-operative EF was 24.7% (95% CI 22.5-27.0%). The operative mortality among patients (26 studies, n= 3621) who underwent on-pump CABG was 5.4%, n= 189 (95% CI 4.5-6.4%). The 5-year actuarial survival among patients (13 studies, n= 1980) who underwent on-pump CABG was 73.4%, n= 1483 (95% CI 68.7-77.7%). Patients who underwent off-pump CABG (7 studies, n= 498) tended to have reduced operative mortality of 4.4%, n= 20 (95% CI 2.8-6.4%). The mean (estimate) post-operative EF was 35.19% (95% CI 31.95-38.43%).

The present meta-analysis demonstrates that based on data from available observational clinical studies, CABG can be performed with acceptable operative mortality and 5-year actuarial survival in patients with severe LV dysfunction.