Increased Risk Associated With Combined Carotid Endarterectomy and Coronary Artery Bypass Graft Surgery: A Propensity-Matched Comparison With Isolated Coronary Artery Bypass Graft Surgery

Objective: Risk associated with combined carotid endarterectomy and coronary artery bypass graft surgery (CEA/CABG) is controversial. The present study objective was to compare morbidity and mortality outcomes in well-matched patients who underwent combined CEA/CABG surgery with patients undergoing isolated CABG surgery with and without a history of a prior CEA. Design: This investigation was designed as a retrospective case-controlled study using data from the Cardiothoracic Anesthesia Patient Registry in a single tertiary institution. The patient population consisted of 1,698 isolated CABG surgery patients with carotid artery stenosis >40%, 708 patients who underwent an isolated CABG surgery but had a history of a prior CEA, and 272 combined CEA/CABG surgery patients who underwent surgery from January 4, 1993, through June 30, 2003. Propensity modeling techniques were used to calculate a propensity score for each patient. Greedy matching resulted in 272 propensity-matched pairs of combined CEA/CABG and isolated CABG patients (primary analysis) and 241 propensity-matched pairs of combined CEA/CABG surgery and isolated CABG surgery with previous CEA patients (secondary analysis). A Fisher exact, chi-square, Wilcoxon rank sum, and Student t test were applied appropriately to compare the propensity-matched pairs. Results: The distribution of covariates among the propensity-matched combined CEA/CABG and isolated CABG groups were similar. Among the propensity-matched pairs in the primary analysis, overall morbidity and mortality were higher in the combined CEA/CABG group compared with the CABG group alone (overall morbidity 15% v 8.8%, p = 0.025, and mortality 5.2% v 1.1%, p = 0.007, respectively). Median intensive care unit (ICU) length of stay was longer (47 v 31 hours, p = 0.004) and hospital length of stay was longer (12 v 9 days, p < 0.001) for the combined CEA/CABG surgery compared with isolated CABG surgery, respectively. Postoperative cardiac, neurologic, serious infection, and renal morbid events were similar between the 2 groups. In the secondary analysis, the rates of mortality, overall morbidity, and neurologic morbidity were similar between the groups, whereas the median ICU and hospital length of stay were significantly longer in the combined CEA/CABG group (47.6 v 39.8 hours, p = 0.025, and 12.0 v 9.0 days, p < 0.001, respectively). Conclusions: Increased mortality and overall morbidity outcomes were found in the combined CEA/CABG group when compared with well-matched isolated CABG patients, but similar when compared with well-matched isolated CABG patients with a history of previous CEA. Patients undergoing combined CEA/CABG procedures had significantly longer ICU and hospital lengths of stay compared with patients undergoing isolated CABG procedures.