Patient-specific bicuspid aortic valve hemodynamics study based on computer simulation and in vitro experiment  

基于计算机仿真和体外实验的患者特异性二叶式主动脉瓣膜血流动力学研究

作　　者：Wentao Yan Jianming Li Bowen Zhang Wenshuo Wang Lai Wei Hongyi Yu Shengzhang Wang 颜文涛;黎健明;张博文;王文硕;魏来;郁红漪;王盛章

机构地区：[1]Department of Aeronautics and Astronautics,Fudan University,Shanghai 200433,China [2]Shanghai Institute of Medical Device Testing,Shanghai 201318,China [3]Department of Vascular Surgery,Zhongshan Hospital Affiliated to Fudan University,Shanghai 200032,China [4]Institute of Biomedical Engineering Technology,Academy for Engineering and Technology,Fudan University,Shanghai 200433,China

出　　处：《Acta Mechanica Sinica》2024年第9期35-46,共12页力学学报（英文版）

基　　金：supported by Zhuhai Fudan Innovation Institute and Science and Technology Project of Shanghai Administration for Market Regulation(Grant No.2022-71).

摘　　要：Bicuspid aortic valve(BAV)is a common congenital malformation of the aortic valve with various structural characteristics.Different types of BAV can cause secondary aortic diseases,including calcific aortic valve stenosis and aortic dilation,although their pathogenesis remains unclear.In this study,we first established patient-specific BAV simulation models and silicone models(Type 0 A-P,Type 1 R-N,and Type 1 L-R)based on clinical computed tomography angiography(CTA)and pressure data.Next,we applied a research method combining fluid-structure interaction(FSI)simulation and digital particle image velocimetry(DPIV)experiment to quantitatively analyze the hemodynamic,structural mechanical,and flow field characteristics of patients with different BAV types.Simulation-based hemodynamic parameters and experimental results were consistent with clinical data,affirming the accuracy of the model.The location of the maximum principal strain in the patientspecific model was associated with the calcification site,which characterized the mechanism of secondary aortic valve stenosis.The maximum wall shear stress(WSS)of the patient-specific model(>67.1 Pa)exceeded 37.9 Pa and could cause endothelial surface injury as well as remodeling under long-term exposure,thus increasing the risk of aortic dilation.The distribution of WSS was mainly caused by BAV type,resulting in different degrees of dilation in different parts guided by the type.The patient-specific model revealed a maximum viscous shear stress(VSS)value of 5.23 Pa,which was smaller than the threshold for shear-induced hemolysis of red blood cells(150 Pa)and platelet activation(10 Pa),but close to the threshold for platelet sensitization(6 Pa).The results of flow field characteristics revealed a low risk of hemolysis but a relative high risk of thrombus formation in the patient-specific model.This study not only provides a basis for future comprehensive research on BAV diseases,but also generates relevant insights for theoretical guidance for calcific aortic valve stenosi二叶式主动脉瓣(BAV)是一种常见的先天性的主动脉瓣膜畸形,具有多种畸形结构表征.不同分型BAV可导致继发性的主动脉疾病,包括钙化性主动脉瓣狭窄和主动脉扩张,但其病因目前仍具争议.本研究基于临床CTA数据和压力数据,建立了三种分型的患者特异性的BAV仿真模型和硅胶模型(Type 0 A-P、Type 1 R-N和Type 1 L-R),采用流固耦合仿真和数字粒子图像测速实验相结合的研究方法,定量分析不同分型BAV患者的血流动力学、结构力学特征和流场特性.研究结果表明,仿真和实验研究的血流动力学参数与临床数据相一致,验证了模型的准确性.患者特异性模型最大主应变较高的位置与钙化部位关系表征继发性主动脉瓣狭窄的机制,患者特异性模型主动脉壁面切应力峰值(>67.1 Pa)超过37.9 Pa,并在此切应力下长期作用可导致内皮细胞表面损伤而发生重塑,从而增加主动脉扩张的风险,而主动脉壁面切应力分布主要是由BAV分型直接导致的,因此会出现以分型为导向的不同部位不同程度的扩张.患者特异性模型黏性切应力峰值最大为5.23 Pa,其值小于剪切诱导红细胞发生溶血的阈值(150 Pa)和血小板活化的阈值(10 Pa),但与血小板致敏的阈值(6 Pa)接近,流场特性指标的结果表明患者特异性模型发生溶血的风险低,而存在血栓形成的风险.本研究提供了一套全面的BAV疾病的研究方法,为不同分型的BAV引起的钙化性主动脉瓣膜狭窄和主动脉扩张提供一定理论依据和指导,为BAV潜在的溶血和血栓形成风险提供生物力学依据,对于BAV的临床诊断和治疗有重要价值.

关 键 词：Bicuspid aortic valve Digital particle image velocimetry Fluid-structure interaction HEMODYNAMICS Patient-specific model 

分 类 号：R54[医药卫生—心血管疾病]