Siegel J M, Markou C P, Ku D N, Hanson S R
George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta 30332-0405.
J Biomech Eng. 1994 Nov;116(4):446-51. doi: 10.1115/1.2895795.
Atherosclerosis of the human arterial system produces major clinical symptoms when the plaque advances to create a high-grade stenosis. The hemodynamic shear rates produced in high-grade stenoses are important in the understanding of atheromatous plaque rupture and thrombosis. This study was designed to quantify the physiologic stress levels experienced by endothelial cells and platelets in the region of vascular stenoses. The steady hemodynamic flow field was solved for stenoses with percent area reductions of 50, 75, and 90 percent over a range of physiologic Reynolds numbers (100-400). The maximum wall shear rate in the throat region can be shown to vary by the square root of the Reynolds number. The shear rate results can be generalized to apply to a range of stenosis lengths and flow rates. Using dimensions typical for a human carotid or coronary artery, wall shear rates were found to vary from a maximum of 20,000 s-1 upstream of the throat to a minimum of -630 s-1 in the recirculation zone for a 90 percent stenosis. An example is given which illustrates how these values can be used to understand the relationship between hemodynamic shear and platelet deposition.
当人类动脉系统中的动脉粥样硬化斑块进展至造成高度狭窄时，就会产生主要的临床症状。高度狭窄处产生的血流动力学剪切速率对于理解动脉粥样硬化斑块破裂和血栓形成很重要。本研究旨在量化血管狭窄区域内内皮细胞和血小板所经历的生理应激水平。在一系列生理雷诺数（100 - 400）范围内，求解了面积减少百分比分别为50%、75%和90%的狭窄处的稳定血流动力学流场。结果表明，喉部区域的最大壁面剪切速率随雷诺数的平方根而变化。剪切速率结果可以推广应用于一系列狭窄长度和流速情况。采用人类颈动脉或冠状动脉的典型尺寸，对于90%狭窄的情况，发现壁面剪切速率从喉部上游的最大值20000 s⁻¹变化到再循环区域的最小值 - 630 s⁻¹。给出了一个示例，说明如何利用这些值来理解血流动力学剪切与血小板沉积之间的关系。
