RISK-FACTORS FOR STROKE FOLLOWING CORONARY-BYPASS SURGERY

Improvements in surgical technique and advances in myocardial protecti on have resulted in low rates of morbidity and mortality despite a gre ater incidence of high-risk patients. Noncardiac morbidity prolongs ho spital stays and increases the costs of cardiac surgery. This study ex amines the preoperative predictors of stroke following isolated corona ry bypass surgery. The clinical records of 3910 consecutive patients w ho underwent isolated coronary bypass surgery at the University of Tor onto were reviewed. Stepwise logistic regression identified six indepe ndent predictors of stroke following CABG (percent in parentheses) and calculated factor adjusted odds ratios (OR) for each risk factor. Tri ple vessel coronary artery disease was the most important predictor (1 .9%, OR 5.71), followed by normothermic systemic perfusion (3.8%, OR 4 .85), age > 70 years (3.2%, OR 3.88), a previous history of transient ischemic attacks or stroke prior to surgery (6.1%, OR 3.7), peripheral vascular disease (4.7%, OR 2.77), and diabetes mellitus (2.6%, OR 2.0 1). The mechanism of stroke is likely different between these high-ris k groups and strategies to prevent postoperative stroke should focus o n the mechanisms responsible in high-risk patients.