Purpose: There is a paucity of comparative data examining the optimal revascularization strategy in patients with left ventricular systolic dysfunction (LVD).
Methods: We performed an aggregate data meta-analysis of clinical outcomes comparing percutaneous coronary intervention (PCI) versus coronary artery bypass (CABG) in patients with LVD (left ventricle ejection fraction (LVEF) of ≤ 40%), using the random effects model. Effects size is reported as odds ratio (OR) and a 95% confidence interval. Outcomes included all-cause mortality, myocardial infarction, stroke, repeat revascularization, and a composite of major adverse cardiac and cerebrovascular events (MACCE) at 30-day, 3-year, and long-term (6.3 ± 0.9 years) follow-ups. Seventeen studies (16 observational, 1 randomized) and 18,599 patients (CABG 9651; PCI 8948) were included.
Results: PCI and CABG had comparable all-cause mortality at 30 days (OR 0.78, 95% CI 0.49-1.23) and 3 years (OR 1.05, 95% CI 0.91-1.21); however, PCI was associated with increased long-term morality after a mean follow-up of 6.3 ± 0.9 years (31.6% vs. 24.3%, OR 1.41, 95% CI 1.21-1.64). A similar mortality trend was observed in the subgroup of patients with EF ≤ 35%. PCI had a higher rate of repeat revascularization at 3-year and long-term follow-ups. The long-term rates of stroke and MI were comparable. PCI, on the other hand, had lower rates of stroke at 30-day and 3-year follow-ups.
Conclusion: CABG was associated with lower rates of long-term mortality and revascularization but higher rate of upfront stroke in patients with LVD. However, the data included consisted predominantly of observational studies, highlighting the paucity and need for randomized trials.
Keywords: Cardiomyopathy; Coronary artery bypass; Ejection fraction; Left ventricular systolic dysfunction; Percutaneous coronary intervention; Revascularization.