管壁切应力在冠状动脉粥样硬化中的重要作用:狭窄冠状动脉的有限元研究

The important role of wall shear stress in coronary atherosclerosis: finite element study of stenosis coronary artery

目的基于冠状动脉CT造影数据建立不同狭窄程度冠状动脉的有限元模型,并进行流体力学模拟研究,分析管壁切应力（WSS）的变化情况及其在动脉粥样硬化中的关键作用。方法利用临床患者狭窄冠状动脉的冠状动脉CT造影数据,建立精确解剖的三维模型;再使用有限元软件建立有限元模型,设置各种边界条件进行模拟分析;最后采用各种图形形式输出结果,进行分析研究。结果冠状动脉狭窄处WSS明显升高,且随着血管狭窄程度的增加而逐渐升高;狭窄后区域WSS减低,与血管狭窄程度呈反比,二者之间存在切应力梯度,且随着血管狭窄程度的增加逐渐增大。结论 WSS的变化会导致粥样斑块的发生发展,在动脉粥样硬化的发病机制中扮演着重要的角色。

Aim Based on coronary artery CT angiography data,to establish the finite element model of coronary artery with different degrees of stenosis and to study the simulative hemodynamics; To analyze the change of wall shear stress（ WSS） and its key role in atherosclerosis. Methods Using the data of coronary artery CT angiography in patients with coronary artery stenosis,a three-dimensional model of precise anatomy was established. The finite element software was used to establish the finite element model,and various boundary conditions were set up for simulation analysis.At last the calculation and analysis were performed,and the results were obtained in the form of a graph. Results The WSS of coronary artery was increased significantly at stenosis place,and gradually increased with the increase of the degree of vascular stenosis. The WSS was decreased at the area behind stenosis,and was reverse proportional to the degree of coronary artery stenosis. There was a shear stress gradient between the two,and gradually increased with the increase of vascular stenosis degree. Conclusion The changes of WSS can lead to the development of atherosclerotic plaques and play an important role in the pathogenesis of atherosclerosis.