The effect off-pump coronary artery bypass surgery on in-hospital mortality and morbidity

Objective: Off-pump coronary artery bypass (OPCAB) surgery is being increasingly reported to show better outcomes compared to conventional on bypass grafting. We examined the effect of OPCAB on in-hospital mortality and morbidity, while adjusting for patient and disease characteristics, in four institutions in the North West of England. Methods: Between April 1997 and March 2001, 10 941 consecutive patients underwent isolated coronary artery bypass surgery at these four institutions. Of these, 7.7% were performed off-pump. We used logistic regression to examine the effect of OPCAB on in-hospital mortality and morbidity after adjusting for potentially confounding variables. Results: The crude odds ratio (OR) for death (off-pump versus on-pump coronary bypass grafting) was 0.48 (95% confidence interval, CI 0.26-0.92; P=0.023). After adjustment for all major risk factors, the OR for death was 0.59 (95% CI 0.31-1.12; P=0.105). Off-pump patients had a substantially reduced risk of post-operative stroke (0.6 versus 2.3%, respectively; adjusted OR 0.26 (95% CI 0.09-0.70; P=0.008) and a significant reduction in post-operative hospital stay. Other morbidity outcomes were similar in both groups. Conclusions: Off-pump coronary artery bypass incurs no increased risk of in-hospital mortality. In contrast, there is a significant reduction in morbidity in patients undergoing off-pump coronary bypass grafting when compared to that performed on cardiopulmonary bypass. © 2002 Elsevier Science B.V. All rights reserved.