Off-Pump Conversion: In-hospital Mortality and Long-Term Survival

Background There is an ongoing debate on the benefits and risks of off-pump coronary artery bypass grafting (CABG) surgery. The fate of patients who start with their procedure being an off-pump one and then have to undergo conversion to an on-pump procedure is debated with regard to in-hospital mortality and unknown with regard to long-term survival. We investigated the in-hospital mortality and long-term survival of patients who underwent conversion from off- to on-pump surgery. Methods We performed a multivariate and propensity analysis on in-hospital mortality and long-term survival of postisolated CABG patients in a single institution having 15,704 patients of which 5,353 who underwent off-pump CABG were analyzed. Results In-hospital mortality was 2.15% for the study cohort, and 73 (1.4%) off-pump cases were converted. Univariate analysis demonstrated that patients undergoing conversion had a significantly increased in-hospital mortality (p < 0.001) and reduced long-term survival (p = 0.002). Logistic regression (receiver operating curve 0.77, Hosmer-Lemeshow test 0.46) and Cox analysis demonstrated that in-hospital mortality and long-term survival were not significantly affected by conversion. Propensity analysis (one:many match) demonstrated that in-hospital mortality was not significantly affected (p = 0.7), and long-term survival - univariate, and multivariate were also not significantly reduced in patients undergoing conversion. Conclusion Conversion from off- to on-pump by a team of surgeons and anesthetists who are dedicated off-pump specialists does not have an impact on in-hospital mortality or long-term survival.