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Background: There have been only a few studies investigating the association between arterial stiffness and acute cerebral small vessel disease (SVD), which showed conflicting results. Objective: The aim of this study was to determine the association of brachial-ankle pulse wave velocity with acute SVD. Patients and Methods: We identified 1145 consecutive patients with acute ischemic stroke who underwent both MR imaging and brachial-ankle pulse-wave velocity (baPWV) measurement. The association between baPWV and acute SVD was tested using linear and logistic regression analyses. This study was approved by the local institutional review boards. Results: Mean age of patients was 68 (±12) years. Mean baPWV levels were 20.7 (±5.1) m/s in patients with large artery atherosclerosis, 20.7 (±4.9) m/s in patients with cardioembolism, 21.3 (±5.2) m/s in patients with small vessel occlusion, 17.8 (±6.3) m/s in patients with other determined etiology, and 20.2 (±5.1) m/s in patients with undetermined etiology. On bivariate analysis, a 1-SD increase in baPWV was associated with acute small vessel occlusion (OR, 1.16; 95% CI, 1.02-1.32). The association remained significant even after adjustment for confounders. Conclusion: baPWV is associated with acute SVD. Our findings suggest that arterial stiffness is linked to the pathogenesis of SVD. In future trials, it should be tested whether arterial stiffness can be a therapeutic target for SVD.

This paper presents the reduction of frictional drag by using the slip on the interface of convex air bubble. The visualization shows that the convex bubbles formed naturally in the hydrophobic cavity array positioned along a microchannel with time. The size of the bubbles depended on the size of the cavity size. The velocity distribution was also displayed by using a micro-PIV measurement. Then, the volume flow rate and the momentum were examined by increasing inlet flow rate for the different sizes of microbubble. The maximum reduction of frictional drag of 52 % was obtained.