导管泵辅助狭窄冠状动脉血流动力学的数值模拟

Numerical simulation of catheter pump-assisted narrowed coronary artery hemodynamics in stenosis

针对导管泵辅助心血管及冠状动脉系统构建了多尺度模型,并对其血流动力学行为进行研究.建立心血管及冠状动脉系统的集总参数模型,宏观分析了导管泵辅助下的心衰合并冠脉狭窄患者的血流动力学参数,并结合计算流体动力学方法研究病理及导管泵辅助下系统的微观流动特性.结果表明:冠状动脉的狭窄程度、狭窄分支对冠状动脉血流影响显著,且左主干狭窄对血流量下降速度影响大于右冠,狭窄部位血流速度及壁面切应力急速上升,并在远心端出现低流速区域以及随狭窄程度加重而增加的涡流等紊流现象;导管泵辅助下冠脉血流量有效提升,一定程度上降低狭窄对血管壁的切应力和流速峰值.导管泵辅助可对心衰合并冠脉狭窄患者的血流动力学参数产生积极影响,具有一定的临床应用价值.

A multi-scale model was developed to study the hemodynamic behavior of the cardiovascu-lar and coronary artery system assisted by a catheter pump.The lumped parameter model was established,and the hemodynamic parameters of heart failure patients with coronary stenosis under catheter pump assistance were analyzed macroscopically.The micro-flow characteristics of the system under pathological conditions and catheter pump assistance were studied by using computational fluid dyna-mics(CFD).The results show that the degree of coronary stenosis and stenotic branches have a significant impact on blood flow,and left main artery stenosis has a greater effect on the rate of blood flow reduction than right coronary artery.The blood flow velocity and wall shear stress increase rapidly in the stenotic region,with the appearance of low flow rate area and turbulence phenomenon increasing with the severity of stenosis.Catheter pump assistance effectively increases coronary blood flow and reduces peak wall shear stress and peak flow velocity on the vessel wall caused by stenosis.In conclusion,catheter pump assistance has a positive effect on hemodynamic parameters in heart failure patients with coronary stenosis,and has certain clinical application value.