Neurological and cognitive disorders after coronary artery bypass grafting

Cerebral injury is a major cause of mortality and morbidity of coronary art ery bypass grafting. Stroke occurs in 3% of patients and is largely caused by embolization of atheromatous debris during manipulation of the diseased aorta. Cognitive impairment, which is predominantly caused by microemboliza tion of gaseous and particulate matter, mainly generated by cardiotomy suct ion, is more common. Demonstration of similar cognitive impairment in patie nts operated on without cardiopulmonary bypass indicates that other pathoph ysiological mechanisms, such as anaesthesia and hypoperfusion, are also inv olved. Advances in medical, anesthetic, and surgical management have result ed in a reduction in the incidence of neurological injury in CABG patients over the past decade. On the other hand, an increasingly elderly population with more severe comorbidity, who are more prone to cerebral injury, are i ncreasingly being referred for CABG. Possible mechanisms to reduce overt an d subtle cerebral injury are discussed. The use of composite arterial graft s performed on the beating heart may be the most effective way of minimizin g the risk of cerebral injury associated with CABG. (C) 2001 Lippincott Wil liams & Wilkins, Inc.