Long-Term Outcomes After Off-Pump Versus On-Pump Coronary Artery Bypass Grafting by Experienced Surgeons

Long-term benefits of off-pump versus on-pump coronary artery bypass grafting (CABG) are controversial.

The authors sought to compare long-term survival and morbidity after on-pump versus off-pump CABG.

Mandatory clinical and administrative registries from New Jersey Department of Health were linked to identify patients who underwent CABG between 2005 and 2011, by surgeons who had performed at least 100 off-pump or on-pump CABG operations. Survival, stroke, myocardial infarction, repeat revascularization, and new dialysis requirement were compared using Cox modeling, propensity scores, and instrumental variable analysis. Median follow-up was 6.8 years (range: 0 to 11.0 years); last follow-up date was December 31, 2015.

Among 42,570 CABG patients, 6,950 who underwent off-pump CABG and 15,295 who underwent on-pump CABG met study criteria. Off-pump CABG was associated with higher mortality (33.4% vs. 29.6% at 10 years; hazard ratio [HR]: 1.11; 95% confidence interval [CI]: 1.04 to 1.18; p = 0.002) compared with on-pump CABG. Off-pump CABG was associated with a higher risk of incomplete revascularization (15.7% vs. 8.8%; p < 0.001), which was a predictor of late mortality (HR: 1.10; 95% CI: 1.03 to 1.17; p = 0.006); and higher rates of repeat revascularization (15.4% vs. 14.0% at 10 years; HR: 1.17; 95% CI: 1.01 to 1.37; p = 0.048). There were no significant differences in the rate of stroke, myocardial infarction, or new dialysis.

In this mandatory clinical registry, off-pump was associated with increased incomplete revascularization, repeat revascularization, and mortality at 10 years compared with on-pump CABG, suggesting that on-pump CABG may be the appropriate choice for most patients undergoing surgical revascularization.