Meta-Analysis Comparing ≥10-Year Mortality of Off-Pump Versus On-Pump Coronary Artery Bypass Grafting

Off-pump coronary artery bypass grafting (CABG) is suggested to be associated with an increase in long-term (≥5-year) all-cause mortality. To determine whether off-pump CABG is associated with an increase in very long-term (≥10-year) all-cause mortality, we performed a meta-analysis of propensity-score matched observational comparative studies of off-pump versus on-pump CABG. MEDLINE and EMBASE were searched through May 2017. A hazard ratio of follow-up (including early) all-cause mortality for off-pump versus on-pump CABG was extracted from each individual study. Study-specific estimates were combined using inverse variance-weighted averages of logarithmic hazard ratios in the random-effects model. Of 164 potentially relevant studies, our search identified 16 propensity-score matched observational comparative studies of off-pump versus on-pump CABG with ≥10-year follow-up enrolling a total of 82,316 patients. A pooled analysis of all the 16 studies demonstrated that off-pump CABG was significantly associated with an increase in all-cause mortality (hazard ratio 1.07, 95% confidence interval 1.03 to 1.12, p for effect = 0.0008; p for heterogeneity = 0.30, I2 = 12%). In a sensitivity analysis, exclusion of any single hazard ratio from the analysis (leave-one-out meta-analysis) did not substantively alter the overall result. There was no evidence of a significant publication bias. In conclusion, off-pump CABG is associated with an increase in very long-term (≥10 years) all-cause mortality compared with on-pump CABG.