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

Abstract

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. 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. 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. 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.