生物主动脉瓣膜设计中的有限元分析模型

目的 为了更好地分析生物心脏瓣膜的应力分布及闭合性能,本研究提出一种新的有限元分析模型.方法 利用点点接触将瓣膜与支架的缝合点一一对应以模拟瓣膜实际缝制过程,建立将平面设计的瓣膜缝制到支架上的模型,从而形成缝制模型.而对照模型则直接建立瓣叶的理想三维几何结构.在两种模型的瓣叶上施加一定压力,进行有限元计算,将缝制模型与对照模型的应力分布情况进行对比,同时参照实际瓣膜的闭合情况对比上述两种模型的闭合形态.结果 缝制模型最大应力集中部位为瓣叶两翼,其瓣叶倾角及闭合形态分析均较可靠.结论有限元缝制模型可以为心脏瓣膜瓣叶性能分析提供比对照模型更精确的结果,从而为瓣叶形状的设计和优化提供指导依据.

A new finite element analysis model in biological aortic heart valve design

Objective This paper proposes a new finite element analysis （FEA）model to mimic the actual valve shape and investigate the stress distribution and closure performance of leaflet. Methods In the suture model,two-dimensional design of leaflet is transferred to 3D model by FEA method which mimics the suture process. The contrast model,which is created by an ideal 3D geometry structure of valve,is utilized to compare the stress distribution differences between suture and contrast models. Meanwhile, the actual close state is investigated to validate the effectiveness of two models. Results The closing state and the angle of leaflet are reliable in the suture model with the wings of the valve leaflets being the maximum stress positions. Conclusions The FEA suture model can provide more accurate results for heart valve leaflet performance analysis than the contrast model, and offer the guide for the design and the optimization of the valve leaflet shape.