Long-Term Outcomes after Redo Coronary Artery Bypass Grafting: A Propensity-Matched Analysis of On-Pump and Off-Pump Techniques

Abstract Redo coronary artery bypass grafting (redo-CABG) is technically challenging and carries a higher perioperative risk than primary CABG. Whether avoiding cardiopulmonary bypass is beneficial in this setting remains unclear. We compared perioperative and long-term outcomes of off-pump versus on-pump redo-CABG in a high-volume center. All patients undergoing redo-CABG between 2009 and 2024 were retrospectively analyzed. Perioperative, in-hospital, and long-term outcomes were evaluated. Propensity score matching was performed using preoperative covariates. Survival analyses included a subgroup of beating-heart on-pump cases. Completeness of revascularization was likewise assessed. Among 370 patients (175 off-pump group; 195 on-pump group), 184 were propensity score-matched. Off-pump surgery had shorter operative time (183 vs. 208 min; p = 0.015) and reduced red blood cell transfusion requirements (3 vs. 5 units; p = 0.014). Myocardial injury biomarkers were reduced with off-pump surgery (CK-MB: 45 vs. 68 ng/mL, p = 0.01; high-sensitivity troponin: 3,388 vs. 7,744 ng/L, p = 0.001). In-hospital mortality was comparable (off-pump group 2.2 vs. 1.1% in the on-pump group; p = 0.621; relative risk: 1.34). Rates of stroke, myocardial infarction, cardiopulmonary resuscitation, and hemofiltration did not differ. Five-year repeat revascularization rates were similar (off-pump group: 18.5 vs. 19.6% in the on-pump group; p = 0.854). Long-term survival did not differ between strategies. In multivariable analysis, surgical strategy (off-pump, on-pump, beating-heart) was not an independent predictor of survival. Off-pump redo-CABG is safe and yields outcomes similar to on-pump surgery. Pump strategy should be individualized based on patient's anatomy and surgical expertise.