生物瓣膜应力的数值模拟

Numerical Simulation of the Stress for Bioprosthetic Heart Valve Leaflets

应用有限元方法分析了瓣架的材料特性、瓣叶的材料特性和瓣叶的钙化等因素对瓣叶的应力分布的影响。分析结果表明 :采用全弹性材料的瓣架将改善瓣叶的应力分布 ,最大应力区域将远离接缝部位 ;将生物瓣瓣叶材料简化为拟线弹性材料时 ,对瓣叶最大主应力等值线的分布影响不大 ,计算结果在一定范围内存在差异 ;当瓣叶出现钙化时 ,钙化点及其周围产生应力集中 ,促进钙化的进一步加剧。

The stress distribution of bioprosthetic heart valve leaflets affected by the material of frame, material of leaflets and calcification is analyzed by using finite element method. The results show that the stress distribution of leaflets is improved and the maximum stress zone locates far away from the bonding part by using fully-elasticity material frame. The rule of distribution of stress is not affected obviously by the hyper-elasticity material of leaflets simplifying to imitative-linear-elastic material, but there is a certain error. It also indicates that the stress concentration occurs around the calcific dot in the leaflets. Concentration stress leads to calcifying the valve leaflet near the point of calcification further seriously.