Wall shear stress in hypertensive patients is associated with carotid vascular deformation assessed by speckle tracking strain imaging

Abstract

Introduction: Wall shear stress (WSS) is critically important in both vascular remodeling and atherosclerosis. Carotid intima-media thickness (IMT) and deformation parameters have been used as relevant indicators of carotid atherosclerosis. This study aimed to investigate the relationships between hemodynamic parameters in the common carotid artery (CCA) and the severity of carotid atherosclerosis in untreated hypertensive patients.

Methods: Carotid artery ultrasound was performed in 100 untreated hypertensive patients. Morphologic and hemodynamic parameters of the CCA, including peak and mean WSS, global circumferential strain, peak posterior radial strain assessed by two-dimensional speckle tracking method, and IMT, were measured.

Results: In patients with hypertension, there were significant correlations between carotid strain parameters and peak/mean WSS. Stepwise multiple regression analysis for carotid strain parameters after adjustment for age, carotid IMT, and brachial pulse wave velocity showed that peak WSS was an independent determinant of peak posterior radial strain (p = 0.009) and global circumferential strain (p = 0.002).

Conclusions: These findings indicate that local shear stress is associated with carotid vascular deformation, which could be an underlying mechanism for the progression of atherosclerosis.

Keywords: Carotid arteries; Hypertension; Shear stress; Strain.

Figure 1

Regression analysis between peak wall shear stress (WSS) and carotid deformation parameters assessed by speckle tracking echocardiography. (A) Global circumferential strain and (B) peak posterior radial stain showed a significant positive correlation with peak WSS. (C) Brachial ankle pulse wave velocity (baPWV) showed a significant negative correlation with peak WSS.