Propensity case-matched analysis of off-pump versus on-pump coronary artery bypass grafting in patients with atheromatous aorta.

BACKGROUND

Patients with severe atheromatous disease of the aorta who underwent coronary artery bypass grafting have an increased risk of stroke and death. We hypothesize that in these high-risk patients off-pump coronary artery bypass grafting is associated with lower rates of stroke and mortality.

METHODS

From January 1995 through June 2004, a total of 24,107 patients underwent coronary artery bypass grafting. Routine intraoperative transesophageal echocardiography was performed in 18,501, of which 6,991 (29.0%) were found to have severe atheromatous disease in the ascending aorta or aortic arch. Propensity matched-pairs analysis was used to match patients undergoing off-pump coronary artery bypass grafting (n = 3,000) with 3,000 patients undergoing conventional coronary artery bypass grafting by age, sex, ejection fraction, diabetes, preoperative intraaortic balloon pump, congestive heart failure, chronic obstructive pulmonary disease, acute myocardial infarction, peripheral vascular disease, history of stroke or cerebrovascular disease, renal disease, carotid artery disease, atrial fibrillation, emergency surgery, or previous cardiac surgery.

RESULTS

Univariate analysis revealed decreased hospital mortality (1.4% versus 3.3%; p < 0.001) and stroke prevalence (0.50% versus 0.97%; p = 0.05) in off-pump coronary artery bypass grafting compared with conventional coronary artery bypass grafting. Multivariate analysis revealed that increased mortality was associated with conventional coronary artery bypass grafting (odds ratio, 2.6; p = 0.001), age (odds ratio, 2.1; p = 0.003), acute myocardial infarction (odds ratio, 1.8; p = 0.03), history of stroke or cerebrovascular disease (odds ratio, 1.6; p = 0.04), congestive heart failure (odds ratio, 2.1; p = 0.04), and diabetes mellitus (odds ratio, 1.9; p = 0.03). Multivariate analysis showed that off-pump coronary artery bypass grafting technique was the only independent predictor of decreased stroke rate (odds ratio, 1.4; p = 0.05).

CONCLUSIONS

Off-pump coronary artery bypass grafting surgery in patients with atheromatous disease of the aorta is associated with lower risk of stroke and death. Routine intraoperative evaluation of the aorta is helpful in identifying the disease and directs the appropriate surgical technique.