Degree of Carotid Artery Stenosis in Neurologically Asymptomatic Cardiac Surgical Patients Suffering from Perioperative Stroke: Results of an Observational Study

Background Postoperative stroke in cardiac surgical patients remains a serious adverse outcome. Methods A total of 2,784 consecutively operated cardiac surgical patients without preoperative neurologic impairment were analyzed retrospectively with regard to impact of preoperative carotid stenosis on the incidence of postprocedural new onset of stroke. Therefore, all analyzed patients were assigned to four groups depending on preoperative degree of carotid artery stenosis detected by carotid duplex sonography (group I: < 50%, group II: 50-75%, group III: 76-89%, and group IV: > 90%). Results All pre-, intra-, and postoperative risk factors for neurological disorders were comparable throughout the cohort. Of the 2,784 patients, 65 (2.3%) met the inclusion criteria (preoperatively neurologically asymptomatic status, preoperatively carotid duplex ultrasonography study not older than 6 months, heart surgery with extracorporeal circulation, stroke until 48 hours after operation). Of the 65 patients who met the inclusion criteria, 43 (66.2%) were in group I, 11 (16.9%) in group II, 5 (7.7%) in group III, and 6 (9.2%) in group IV (p = 0.175). The overall incidence of an ipsilateral stroke relating to the carotid stenosis was 38 (1.4%) patients. Of these, 27 (71.1%) patients were in group I, 6 (15.8%) patients in group II, 2 (5.3%) patients in group III, and 3 (7.9%) patients in group IV (p = 0.568). Conclusion This observational study demonstrates that the degree of carotid stenosis in neurologically asymptomatic cardiac surgical patients is not able to predict the probability of perioperative stroke. Until further results from prospective randomized trials with neurologically asymptomatic cardiac surgical patients are presented, a cautious attitude for concomitant carotid endarterectomy is still justified.