Aortic atherosclerosis and postoperative neurological dysfunction in elderly coronary surgical patients

Background Arteriosclerosis of the ascending aorta is an important risk factor for cerebral embolism. However, the association between arteriosclerosis of the ascending aorta and neurologic dysfunction after coronary artery surgery has not been evaluated prospectively. Methods We examined whether varying degrees of arteriosclerosis in the ascending aorta, assessed by epiaortic ultrasonography, increased the incidence of neuropsychologic dysfunction and stroke in 463 elderly patients (≥ 60 years old) after coronary artery surgery. Results Patients with severe arteriosclerosis (n = 76) had higher rates of postoperative neuropsychologic dysfunction (26%) and intraoperative stroke (10.5%); the moderately atherosclerotic patients (n = 57) had rates of 7% and 1.8%, respectively; whereas control patients (almost normal or mild arteriosclerosis, N = 330) had rates of 8% and 1.2%, respectively (all p< 0.001). Univariate analysis indicated that multiple small infarctions or broad infarctions, cerebral arterial stenosis, circulatory arrest, maximal thickness of intima around the site of aortic manipulation, and deformities due to clamp or cannulation were associated significantly with intraoperative strokes in patients with severe arteriosclerosis. Conclusions Severe arteriosclerosis of the ascending aorta significantly increased the risk of postoperative neuropsychologic dysfunction and stroke after coronary artery bypass grafting. If a thick plaque is noted near the manipulation site, a nontouch method of the ascending aorta should be applied to reduce the incidence of neurologic dysfunction.