FLUID WALL SHEAR-STRESS MEASUREMENTS IN A MODEL OF THE HUMAN ABDOMINAL-AORTA - OSCILLATORY BEHAVIOR AND RELATIONSHIP TO ATHEROSCLEROSIS
FLUID WALL SHEAR-STRESS MEASUREMENTS IN A MODEL OF THE HUMAN ABDOMINAL-AORTA - OSCILLATORY BEHAVIOR AND RELATIONSHIP TO ATHEROSCLEROSIS
复制标题
DOI：
10.1016/0021-9150(94)90207-0
复制
发表时间：
1994-10-01
期刊：
影响因子：
5.3
通讯作者：
KU, DN
中科院分区：
文献类型：
--
作者：
MOORE, JE;XU, CP;KU, DN
人类主动脉中临床上显著的动脉粥样硬化最常见于肾下段。这项研究的目的是检验流场特性与动脉系统这一段斑块定位密切相关的假设。壁面剪切应力是根据解剖学上精确的人体腹主动脉模型中脉动流的磁共振速度测量值计算的。壁面切应力值进行了比较，内膜增厚从15个死后的组织学横截面在标准位置获得的定量形态测量法测量。壁面剪应力在整个肾下主动脉的大部分方向上振荡，最突出的是在远端区域。时间平均的平均壁剪切应力（-1.7至1.4 dyn/cm（2））在该区域的后壁附近最低。这些血流动力学参数与最大内膜增厚的位置相吻合。振荡剪切力与内膜厚度之间的统计相关性为r = 0.79，P < 0.00001。低平均剪应力也几乎相关（r =-0.75，P < 0.00005）。我们的数据与苏丹红染色和早期病变的表面图，如其他人报道的比较，揭示了类似的结论。与此相反，脉切应力和最大切应力与斑块定位无关，这与动脉粥样硬化选择性累及的其他部位无关（r < 0.345）。模拟运动条件显著改变了远端腹主动脉壁切应力的大小和模式。这些结果表明，在肾下主动脉中，平均壁切应力和振荡壁切应力较低的区域更容易出现斑块，而壁切应力相对较高的区域往往不会出现斑块。
Clinically significant atherosclerosis in the human aorta is most common in the infrarenal segment. This study was initiated to test the hypothesis that flowfield properties are closely related to the localization of plaques in this segment of the arteial system. Wall shear stress was calculated from magnetic resonance velocity measurements of pulsatile flow in an anatomically accurate model of the human abdominal aorta. The wall shear stress values were compared with intimal thickening from 15 post-mortem aortas measured by quantitative morphometry of histological cross sections obtained at standard locations. Wall shear stress oscillated in direction throughout most of the infrarenal aorta, most prominently in the distal region. The time-averaged mean wall shear stress (-1.7 to 1.4 dyn/cm(2)) was lowest near the posterior wall in this region. These hemodynamic parameters coincided with the locations of maximal intimal thickening. Statistical correlation between oscillatory shear and intimal thickness yielded r = 0.79, P < 0.00001. Low mean shear stresses correlated nearly as well (r = -0.75, P < 0.00005). Comparison of our data with surface maps of Sudan Red staining and early lesions as reported by others revealed similar conclusions. In contrast, pulse and maximum shear stresses did not correlate with plaque localization as has been shown for other sites of selective involvement by atherosclerosis (r < 0.345). Simulated exercise conditions markedly changed the magnitude and pattern of wall shear stress in the distal abdominal aorta. These results demonstrate that in the infrarenal aorta, regions of low mean and oscillating wall shear stresses are predisposed to the development of plaque while regions of relatively high wall shear stress tend to be spared.