Division of Angiology, Department of Medicine II, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria.
Eur J Vasc Endovasc Surg. 2011 Jun;41(6):821-7. doi: 10.1016/j.ejvs.2011.01.006. Epub 2011 Feb 16.
Alterations of wall shear stress (WSS) are considered to precede atherosclerosis. Local variations of WSS might contribute to the typical distribution of atherosclerotic lesions along the superficial femoral artery (SFA). We investigated the course of WSS and its response to postural changes and exercise along the SFA of healthy adults.
In forty-six healthy subjects, we determined flow velocities and internal vessel diameters in five predefined segments of the SFA using duplex ultrasound; measurements were done at rest, following exercise (30 toe raises) and after postural changes (supine and sitting). Peak and mean WSS were calculated from peak systolic and mean velocities, vessel diameter and whole blood viscosity.
At rest, peak and mean WSS did not vary along the femoro-popliteal axis (p > 0.05); peak and mean WSS were lower in the sitting than in the supine position (p < 0.0001). After exercise, peak and mean WSS increased in all segments (p < 0.0001), showing the lowest increase in the distal Hunter's canal.
Healthy adults do not exhibit local variations of WSS in the SFA at rest, but segmental differences in WSS occur after exercise. Whether these findings are related to the typical distribution of atherosclerotic lesions later in life requires further investigation.
壁切应力（WSS）的改变被认为先于动脉粥样硬化。WSS 的局部变化可能导致粥样硬化病变沿股浅动脉（SFA）的典型分布。我们研究了健康成年人 SFA 中 WSS 的变化过程及其对姿势变化和运动的反应。
在 46 名健康受试者中，我们使用双功能超声在 SFA 的五个预设节段确定血流速度和内部血管直径；测量在休息、运动（30 次脚趾抬高）和姿势变化（仰卧位和坐位）后进行。峰值和平均 WSS 由收缩期峰值和平均速度、血管直径和全血粘度计算得出。
在休息时，股浅动脉轴上的峰值和平均 WSS 没有变化（p > 0.05）；坐位时的峰值和平均 WSS 低于仰卧位（p < 0.0001）。运动后，所有节段的峰值和平均 WSS 均增加（p < 0.0001），在远侧 Hunter 管中增加最少。
健康成年人在休息时 SFA 中的 WSS 没有局部变化，但运动后 WSS 出现节段性差异。这些发现是否与以后生活中粥样硬化病变的典型分布有关，需要进一步研究。
