Peking University International Hospital, Beijing, China.
Shenzhen Mindray Bio-Medical Electronics Co., Ltd., Shenzhen, China.
Ultrasound Med Biol. 2023 Aug;49(8):1830-1836. doi: 10.1016/j.ultrasmedbio.2023.04.007. Epub 2023 Jun 1.
The arteriovenous fistula (AVF) is an essential vascular access for hemodialysis patients. AVF stenosis may occur at sites with abnormal wall shear stress (WSS) and oscillatory shear index (OSI), which are caused by the complex flow in the AVF. At present, an effective method for rapid determination of the WSS and OSI of the AVF is lacking. The objective of this study was to apply an ultrasound-based method for determination of the WSS and OSI to explore the risk sites of the AVF.
In this study, the ultrasound vector flow imaging technique V Flow was applied to measure the WSS and OSI at four different regions of the AVF to detect and analyze the risk sites: (i) anastomosis region, (ii) curved region, (iii) proximal vein and (iv) distal vein. Twenty-one patients were included in this study. The relative residence time was calculated based on the measured WSS and OSI.
The curved region had the lowest WSS; the anastomosis region had a significantly higher OSI (p < 0.05) compared with the venous regions, and the curved region had a significantly higher RRT (p < 0.05) compared with the proximal vein region.
V Flow is a feasible tool for studying WSS variations in AVF. The possible risk site in the AVF may be located in the anastomosis and curved regions, where the latter could present a higher risk for AVF stenosis.
动静脉瘘（AVF）是血液透析患者必不可少的血管通路。AVF 狭窄可能发生在壁切应力（WSS）和振荡剪切指数（OSI）异常的部位，这是由 AVF 中的复杂流动引起的。目前，缺乏一种快速确定 AVF 的 WSS 和 OSI 的有效方法。本研究的目的是应用基于超声的方法来确定 WSS 和 OSI，以探讨 AVF 的风险部位。
本研究应用超声向量流成像技术 VFlow 测量 AVF 的四个不同部位的 WSS 和 OSI，以检测和分析风险部位：（i）吻合口区域，（ii）弯曲区域，（iii）近静脉和（iv）远静脉。本研究纳入 21 例患者。根据测量的 WSS 和 OSI 计算相对居留时间。
弯曲区域的 WSS 最低；吻合口区域的 OSI 显著高于静脉区域（p<0.05），弯曲区域的 RRT 显著高于近静脉区域（p<0.05）。
VFlow 是研究 AVF 中 WSS 变化的一种可行工具。AVF 中的可能风险部位可能位于吻合口和弯曲区域，后者可能存在更高的 AVF 狭窄风险。
