Impact of Aortic Stiffness on Ischemic Stroke in Elderly Patients

Abstract

Background and Purpose— Large atherosclerotic plaques in the aortic arch detected by transesophageal echocardiography (TEE) are associated with increased risk of ischemic stroke in the elderly. The atherosclerotic process also affects aortic distensibility, which can also be assessed by TEE. The purpose of this study was to evaluate the possible association of aortic stiffness by TEE with ischemic stroke in elderly patients. Methods— We performed TEE in 40 consecutive elderly patients aged ≥55 years with acute ischemic stroke and in 42 consecutive control subjects aged ≥55 years. Aortic stiffness index &bgr;, which has been used in the literature to express the stiffness of the aortic wall, was calculated as follows: &bgr;=ln (systolic blood pressure/diastolic blood pressure)/([Dmax−Dmin]/Dmin), where ln is natural logarithm, Dmax is maximum aortic lumen diameter, and Dmin is minimum aortic lumen diameter by TEE. The association of index &bgr; with ischemic stroke was evaluated by logistic regression analysis after adjustment for potential confounders, including thickness of aortic arch plaques. Results— Index &bgr; was significantly greater in stroke patients than in controls (9.7±5.0 versus 5.3±3.5;P <0.0001). When aortic plaque thickness and other stroke risk factors were entered in multivariate analysis, index &bgr; was found to be independently associated with ischemic stroke (odds ratio, 1.28 per unit increase; 95% CI, 1.10 to 1.52). Conclusions— Aortic stiffness by TEE is associated with ischemic stroke, independent of thickness of aortic arch plaques and other stroke risk factors. This suggests that aortic stiffness by TEE may add prognostic information when assessing the risk of ischemic stroke in the elderly.