Aim: Wall shear stress (WSS) is the frictional force caused by viscous blood flowing along the vessel wall. Decreased WSS is associated with local vascular endothelial dysfunction and atherosclerosis. The vector flow mapping (VFM) technique detects the direction of intracardiac blood flow and WSS on the vessel wall with echocardiography. In this study, we examined carotid WSS by applying the VFM technique to the carotid arteries and evaluated its relationship with cerebral small vessel disease (SVD).
Methods: This is a single-center, prospective, observational study. We investigated the association between carotid WSS and SVD imaging, and cognitive outcomes in consecutive 113 patients with acute lacunar infarction.
Results: Carotid WSS was negatively associated with age (r=-0.376, p＜0.001). Lower WSS was correlated with total SVD scores (ρ=-0.304, p=0.004), especially with enlarged perivascular space (EPVS) in the basal ganglia ＞10 (p＜0.001). The carotid intima-media thickness was not associated with the total SVD score (ρ=-0.183, p=0.052). Moreover, lower WSS was associated with executive dysfunction.
Conclusion: EPVS has recently been reported as a marker of early SVD imaging, and executive dysfunction is common in vascular cognitive impairment. These results suggested that decreased carotid WSS based on vascular VFM, which can be measured easily, is associated with imaging and cognitive changes in the early stages of SVD.
Keywords: Carotid ultrasonography; Cerebral small vessel disease; Enlarged perivascular space; Vector flow mapping; Wall shear stress.