Long-Term Outcomes of On- Versus Off-Pump Coronary Artery Bypass Grafting

Background: When comparing effects of on- versus off-pump coronary artery bypass grafting (CABG), it is important to assess the long-term clinical outcomes. However, most research conducted thus far has concentrated on short-term outcomes and ignored the long-term clinical outcomes, especially the 5-year outcomes of the largest randomized controlled trials.

Objectives: The aim of this systematic review and meta-analysis was to investigate the long-term clinical outcomes of on- versus off-pump CABG.

Methods: To identify potential studies systematic searches were carried out using various databases. The search strategy included the key concepts of cardiopulmonary bypass AND off-pump AND long term OR 5-year outcomes. This was followed by a meta-analysis investigating mortality, incidence of myocardial infarction, incidence of angina, need for revascularization, and incidence of stroke.

Results: Six studies totaling 8,145 participants were analyzed. In the on-pump group mortality was 12.3%, compared with 13.9% in the off-pump group. The odds ratio (OR) for this comparison was 1.16 (95% confidence interval [CI]: 1.02 to 1.32; p = 0.03; 13.9% vs. 12.3%). In contrast, there were no differences in the incidence of myocardial infarction (OR: 1.06: 95% CI: 0.91 to 1.25; p = 0.45; 8.4% vs. 7.9%), incidence of angina (OR: 1.09; 95% CI: 0.75 to 1.57; p = 0.65; 2.3% vs. 2.1%), need for revascularization (OR: 1.15; 95% CI: 0.95 to 1.40; p = 0.16; 5.9% vs. 5.1%), and the incidence of stroke (OR: 0.78; 95% CI: 0.56 to 1.10; p = 0.16; 2.2% vs. 2.8%).

Conclusions: Statistically, on-pump CABG appeared to offer superior long-term survival, although the clinical significance of this may be more uncertain.