Impaired arterial elastic properties and endothelial glycocalyx in patients with embolic stroke of undetermined source

Abstract

Background and purpose
Cardioembolism is a postulated mechanism of embolic stroke of undetermined source (ESUS). We investigated endothelial glycocalyx, aortic elastic properties, oxidative stress, and their association left atrial (LA) function in ESUS and healthy individuals.

Methods
In 90 ESUS patients (age 50.4±13.2) and 90 controls with similar risk factors, we measured: a) perfused boundary region (PBR) of the sublingual arterial microvessels (range 5–25 micrometers), a marker inversely related with glycocalyx thickness, b) pulse wave velocity (PWV), central systolic blood pressure (cSBP) and augmentation index (AIx), c) LA volume and strain using speckle-tracking imaging, d) Malondialdehyde (MDA) and protein carbonyls (PC), as oxidative stress markers.

Results
Compared to controls, ESUS had higher PWV, PBR MDA, and PC levels as well as higher LA volume and reduced reservoir LA strain (p<0.05). PBR>1.18 μm of microvessel ranging from 5–9μm and PWV>10.2m/s were associated with ESUS on multivariable analysis (odds ratio: 2.374 and 5.429, p<0.05 respectively) and increased the c-statistic of the initial model from 0.54 to 0.71. In ESUS, glycocalyx damage (increased PBR) was related with increased PWV (p<0.01) which was linked with LA reservoir strain after controlling for age, sex, and risk factors [p=0.03]. Increased MDA and PC were related with glycocalyx damage, increased PWV (r=0.67 and r=0.52) AIx, central SBP and aortic atheroma (p<0.01).