Pre- and Perioperative Risk Factors Predicting Neurologic Outcomes after Coronary Artery Bypass Surgery in Patients with Pre-existing Neurologic Events

Background A neurologic event (NE) after coronary artery bypass graft (CABG) surgery is a principal complication affecting morbidity and mortality. We investigated the risk factors predicting postoperative NEs and survival in patients with pre-existing NE undergoing CABG. Methods Between 2001 and 2012, 3137 patients underwent isolated primary CABG. The data were stored in a computerized database and retrospectively evaluated. Patients were divided into 2 groups based on the existence of preoperative NE (study group; n = 126) and without NE (n = 3011). Uni- and multivariate logistic regression analyses were performed to evaluate the possible predictors of postoperative NEs. Survival was determined using Kaplan–Meier survival analyses of the study group and propensity score–matched control group. Results The mean age of the 3137 patients was 60 ± 9 years, and 28% (n = 885) were female. Postoperative NE was seen in 4 (3.2%) patients with pre-existing NE and in 16 (0.5%) without pre-existing NE. Preoperative NE (odds ratio 4.47; 95% confidence interval 1.32-15.18; P = .01) and age (≥70 years; odds ratio 2.98; 95% confidence interval 1.21-7.33; P = .01) showed strong multivariate associations with postoperative NE. Median CHA2 DS2- VASc scores were 4.5 (interquartile range 3-5) and 3 (range 0-4) in patients in the pre-existing and without NE groups, respectively ( P = .01). The overall mean follow-up was 4.6 ± 3 years. Overall survival rates (88.1% and 94%, respectively) were different between the 2 groups ( P = .02). Conclusions Preoperative neurologic events and advanced age are significant risk factors predicting postoperative neurologic events. Meticulous management of the ascending aorta and carotid artery are important in diminishing postoperative neurologic events. A pre-existing neurologic event is also predictive for decreased overall survival.