Off-pump versus on-pump coronary artery bypass grafting in moderate renal failure

Objectives — Off-pump coronary artery bypass (OPCAB) may benefit select high-risk patients. We sought to analyze the long-term outcomes of OPCAB versus on-pump coronary artery bypass (ONCAB) in patients with moderate renal failure.

Methods — A retrospective cohort analysis of primary isolated CAB surgery performed in Ontario, Canada, from October 2008 to March 2016 in the CorHealth Ontario Cardiac Registry identified 50,115 cases. Of these, 7782 (15.5%) had estimated glomerular filtration rate (eGFR) of 30 to 59 mL/min/1.73 m(2). OPCAB was compared to ONCAB after propensity score matching.

Results — Following propensity score matching, 1578 patient pairs were formed. Total number of bypass grafts was higher in ONCAB (3.31 +/- 1.01 vs 3.12 +/- 1.14; P < .01) and more arterial grafts were used in OPCAB (1.55 +/- 0.71 vs 1.14 +/- 0.58; P < .01). OPCAB was associated with lower rate of in-hospital stroke (0.7% vs 2.2%; P < .01), renal failure requiring dialysis (1.2% vs 2.9%; P < .01), and blood transfusion (52.4% vs 69.3%; P < .01). There was no difference in perioperative mortality (2.4% vs 3.0%; P = .36) between OPCAB and ONCAB, respectively. At 8-year follow-up, survival probability was not different when comparing OPCAB versus ONCAB: 62% versus 65%, respectively (hazard ratio, 0.98; 95% confidence interval, 0.84-1.13; P = .38). Cumulative incidence of permanent dialysis did not differ at 8-year follow-up: 7% versus 7%, respectively (hazard ratio, 1.01; 95% confidence interval, 0.72-1.43; P = .74.

Conclusions — OPCAB is associated with improved in-hospital renal outcomes, but is not associated with changes in short- or long-term mortality, or with the long-term cumulative incidence of end-stage renal failure requiring permanent dialysis in patients with moderate renal failure.