Functional Evaluation Of Coronary Artery Stenosis Based On CFD

Stenosis of coronary artery increases blood flow resistance, leading to coronary blood supply area of myocardial ischemia, which causes patients with angina pectoris, sudden death.So it is very important to study the effect on myocardial blood supply of coronary artery stenosis. In this paper, individualized models of coronary artery stenosis were established based on real patients coronary CT angiography image by digital image processing. Fractional Flow Reserve was obtained from finite element numerical simulation evaluate the functional ischemic degree of coronary artery stenosis,which guided the clinical treatment of coronary intervention. In this paper, the specific research contents include the following points:(1) Individualized models of coronary artery stenosis were established by using threshold segmentation and surface rendering method. Comparing hemodynamic parameter of three kinds of optimal threshold calculation method established from CFD. And the study determined the Otsu method which is more suitable for coronary CTA image segmentation.(2) Using CFD studied evaluation of numerical simulation and function on rigid vascular model of coronary stenosis.In the process of numerical model, this paper analyzed the optimal meshing strategy determine and effects of the viscosity coefficient in numerical simulation. Secondly, this paper by finite element finite volume solve the algorithm coronary stenosis regional blood flow control equations and hemodynamics of the numerical model, according to the numerical results of hemodynamic parameters calculated FFR-CT to evaluate coronary artery stenosis.(3) Elasticity of coronary vascular numerical model were established based on real physical parameters and fluid-structure Interaction(Fluid Structure Interaction, FSI) analysis method. The study count the FFR-CT according to the hemodynamic value of it. First of all, to establish a vascular physical model, this paper did a experiment of the pig coronary blood vessels in vitro tensile to measure the coronary blood vessels elastic modulus. Then, this paper by the FSI analysis method calculationed the simulation mode of elastic coronary stenosis vascular hemodynamic,and studied the effects of coronary artery elasticity on hemodynamics and coronary reserve fraction.