Hamid M S, Sabbah H N, Stein P D
J Biomech. 1986;19(9):759-69. doi: 10.1016/0021-9290(86)90199-5.
A finite element model of a bioprosthetic heart valve was developed to determine the influence of the stent height on leaflet stresses under various pressure loading conditions after valve closure. A nonlinear solution was used to obtain the stresses in the leaflets for stent heights of 14.6 mm, 19.0 mm and 22.0 mm respectively. The basic assumptions included an elliptic-paraboloid for a relaxed leaflet shape, a rigid stent, isotropic leaflet material property with a Poisson's ratio of 0.45, a uniform leaflet thickness and a stress dependent Young's modulus. The model predicted an increase of stresses on the closed leaflets as the stent height was reduced. This observation appears to mitigate, to some extent, the hemodynamic benefits thought to accompany the reduction of stent height of bioprosthetic valves.
开发了一个生物人工心脏瓣膜的有限元模型，以确定在瓣膜关闭后各种压力加载条件下，支架高度对瓣叶应力的影响。采用非线性解法分别获得了支架高度为14.6毫米、19.0毫米和22.0毫米时瓣叶中的应力。基本假设包括：松弛瓣叶形状为椭圆抛物面、刚性支架、泊松比为0.45的各向同性瓣叶材料特性、均匀的瓣叶厚度以及与应力相关的杨氏模量。该模型预测，随着支架高度降低，关闭瓣叶上的应力会增加。这一观察结果似乎在一定程度上削弱了人们认为生物人工瓣膜支架高度降低所带来的血流动力学益处。
