Stroke after coronary artery bypass grafting in patients with cerebrovascular disease

Background. Stroke has been associated with a significantly increased mortality from coronary artery bypass grafting (CABG). To determine the predictors of stroke in patients undergoing CABG, we collected data on 472 consecutive patients. Methods. From March 1991 to March 1999, all patients undergoing CABG at our institution underwent routine duplex scanning of the extracranial carotid and vertebral arteries. Seven patients with symtomatic carotid stenosis were treated by carotid endarterectomy (CEA) before CABG. Results. There was a 10-fold increase in mortality (12.5%) associated with postoperative stroke. Many variables were analyzed by a mutivariate technique and the severity of extracranial carotid artery stenosis was determined to be the only independent predictor of postoperative stroke (p< 0.01). None of the patients with carotid artery occlusion and none of the patients who underwent CEA before CABG experienced a stroke. Conclusions. To reduce the stroke rate, the indications for prophylactic CEA may be extended for asymptomatic patients with carotid artery stenosis greater than 75%.