Impaired Endothelial Function in Embolic Stroke of Undetermined Source.

ABSTRACT

BACKGROUND: Impairment of endothelial function is associated with atherosclerosis and atrial fibrillation, and could underlie several types of ischemic stroke. Embolic stroke of undetermined source (ESUS) recently attracted much attention as the major cause of cryptogenic stroke. This study aimed to clarify the endothelial function of patients with ESUS. METHODS AND RESULTS: Between 2015 September and July 2017 July, we used flow-mediated vasodilation (FMD) test to evaluate vascular endothelial function in 182 patients with any vascular risk factors or a history of cerebrovascular events. The subject group was classified into the No Stroke group and 5 stroke subtype groups, large artery atherosclerosis (LAA), cardiogenic embolism (CE), small vessel disease (SVD), ESUS, and others (Other). Endothelial function was expressed as percentage increase in brachial vessel diameter (%FMD) after the interruption of blood flow with mechanical compression for 5 minutes. Mean FMD in the No stroke, LAA, CE, SVD, ESUS and Other groups were 7.03 ± 2.14%, 5.02 ± 2.75%, 4.97 ± 1.62%, 5.19 ± 2.67%, 3.55 ± 1.42%, and 6.55 ± 3.50%, respectively. After the adjustment for confounding factors, FMD was significantly lower in the ESUS group than in the No stroke, SVD, and Other groups. FMD tended to be lower in the ESUS group than in the LAA and CE groups, but the difference was not significant. CONCLUSIONS: Endothelial function was impaired in patients with ESUS and may underlie its pathophysiology.