FFR值与冠动脉狭窄度的数值模拟

目的：利用有限体积法对冠状动脉进行数值模拟，探讨不同狭窄程度的冠状动脉简化模型在舒张期血液的压力分布，并以此计算出（Fractional Flow Reserve,FFR）FFR值，阐明冠状动脉不同狭窄程度与肿值之间的关系，为冠状动脉狭窄的诊断提供参考。方法：以血流动力学基本原理建立不同狭窄度冠脉的物理模型，利用有限体积法，计算不同狭窄几何模型的速度、压力和壁面剪切力等血液流体动力学特征。利用开源软件OpenFOAM对人的冠状动脉不同狭窄程度的简化模型进行血流三维数值模拟。结果：计算获得了人的左冠状动脉不同狭窄程度的血流在舒张期压力分布图。当狭窄程度小于70％，FFR值下降缓慢；当狭窄程度在70％和90％之间内，彤R值下降速度明显加快，当狭窄程度大于90％时，FFR值急速下降，另外，当狭窄程度在大于80％之后，冠脉血管内血流流场的速度压力变化加大。结论：通过对不同狭窄度下冠脉血管血液流体动力学特性的计算，进一步说明有限体积法对冠脉狭窄的模拟问题的计算，人左冠状血管狭窄的百分数与冠脉的FFR值并不是呈线性关系，而是呈曲线样改变。

Coronary Artery Stenosis and FFR Worth Calculation Research

Objective： Numerical simulation of coronary artery by using finite volume method, simplified model of distribution in diastolic blood pressure with different degree of stenosis of coronary artery, and calculate the FFR value, clarifies the relationship between coronary artery stenosis and FFR value, provide a reference for the diagnosis of coronary artery stenosis. Methods： According to the basic principle of hemodynamics in establishing a physical model of different degree of stenosis of coronary artery, using the finite volume method, blood fluid dynamics calculation of different stenosis geometry model of velocity, pressure and wall shear stress, using open source software OpenFOAM simplified model of human coronary artery stenosis degree of three dimensional numerical simulation of flow.Results： The people of the left coronary artery stenosis degree of different flow in diastolic pressure distribution calculation. When the degree of stenosis of less than 70%, the FFR value decreased slowly; when the stenosis degree between 70% and 90%, the FFR value decreased significantly faster, when the degree of stenosis is greater than 90%, the FFR value declined sharply, in addition, when the degree of stenosis in more than 80%, the flow field within the coronary arteries velocity pressure increase. Conclusions： Through the calculation of different degree of stenosis in coronary vascular blood flow dynamics, further explains the simulating calculation of stenosis coronary finite volume method, the percentage of people left coronary vascular stenosis and coronary artery FFR value is not a linear relationship, but a curve like change.