Similar neurobehavioral outcome after valve or coronary artery operations despite differing carotid embolic counts

Objectives: The interrelationships among coronary and valvular operations, microemboli, and neurobehavioral outcome are unclear. We hypothesized that adult patients undergoing cardiac valve operations would have more total em boli delivered to the brain than patients undergoing coronary artery bypass grafting and that this would associate with worse neurobehavioral outcomes . Methods: One hundred ninety-three patients undergoing coronary artery bypas s grafting and 73 patients undergoing cardiac valve operations were compare d. Patients received neurologic, neuro-ophthalmologic, and 11 standardized neurobehavioral tests preoperatively and 5 to 7 days, 1 month, and 6 months postoperatively. Left common carotid Doppler ultrasonographic embolus dete ction was performed intraoperatively. Repeated measures and logistic regres sion analyses of outcome were performed. Results: Patients undergoing either coronary or valve operations were well matched by age (61 +/- 10 and 59 +/- 12 years, respectively), but a signifi cantly greater fraction of patients undergoing valve operations were female , diabetic, or had undergone previous cardiac operations. Neurobehavioral s cores of patients undergoing either coronary artery bypass grafting or card iac valve operations did not differ significantly at any time. Total embolu s counts differed significantly: the median was 105 during coronary artery bypass grafting and 479 during cardiac valve operations (geometric means of 104 and 412, respectively; P = .0001). Significantly more emboli were dete cted in the patients undergoing cardiac valve operations after removal of t he left ventricular vent and after separation from cardiopulmonary bypass, but comparable numbers of emboli were seen in the 2 groups before cardiopul monary bypass. In both groups decreased neurobehavioral performance was app arent at 5 to 7 days, with improvement at 1 and 6 months. Increasing number s of carotid emboli significantly associated with worse performance on the letter cancellation test. There were no significant differences between pat ients undergoing valve and coronary operations in neurobehavioral outcomes, strokes, transient ischemic attacks, or deaths. Conclusions: The significantly greater number of emboli in the group of pat ients undergoing cardiac valve operations is likely the result of the entra inment of intracardiac air. The greater numbers of emboli during cardiac va lve operations do not appear associated with a commensurately greater risk of adverse neurologic or neurobehavioral outcome.