On-pump versus off-pump coronary artery bypass grafting in diabetic patients: a propensity score analysis

Abstract

Background: Diabetic patients are recognized as being at high risk for adverse outcomes after coronary artery bypass grafting. We evaluated our outcomes in diabetic patients to compare the effect of off-pump with on-pump coronary revascularization.

Methods: Between April 1997 and September 2002, 951 consecutive diabetic patients underwent isolated coronary artery bypass grafting. A total of 186 (19.6%) of these patients had off-pump coronary procedures. Multivariate logistic regression was used to assess the effect of off-pump coronary procedures on adverse in-hospital outcomes, while adjusting for patient and disease characteristics by constructing a propensity score from core patient characteristics. The propensity score was the probability of receiving off-pump coronary operation, with a C-statistic of 0.81, and was included along with the comparison variable in a multivariable analysis of outcome. All analysis was performed retrospectively.

Results: Off-pump patients were more likely to be obese (p = 0.032), have left main stem stenosis (p = 0.034), and have undergone prior cardiac operation (p = 0.027). The off-pump group had fewer patients with three-vessel disease compared with the on-pump group. After risk adjusting with propensity score, off-pump patients had a significantly lower incidence of stroke (adjusted odds ratio 0.15; p = 0.039) and renal failure (adjusted odds ratio 0.38; p = 0.036). Off-pump patients also required less blood transfusion (p < 0.001) and had shorter lengths of stay (p < 0.001).

Conclusions: Off-pump coronary operation in diabetic patients significantly reduced postoperative morbidity and length of stay compared with on-pump coronary operation, although no in-hospital survival difference was noted between the two groups.