柔性瓣架对生物心脏瓣膜应力的影响

采用非线性大变形超参数八结点板壳元，针对用猪主动脉瓣制成的人工心瓣所用的瓣架材料，形状，侧边高度等对其应力的影响进行数值模拟分析，其中瓣叶的几何形式保持不变。结果表明：弹性瓣架存在一个合适的弹性模量范围，能使瓣叶的最大应力降低较明显；对同一种瓣叶和具有相同弹性模量的瓣架而言、使瓣架立柱顶端产生位移最大的瓣架形状，往往亦是使瓣叶最大应力降低２的最明显的瓣架形状。

EFFECT OF FLEXIBLE STENT ON STRESS OF BIOPROSTHETIC HEART VALVE

By using nonlinear large deformation, 8-node super-parameter shell elements, the effect of elastic behavior, shape, side height of flexible stent on the maximum stress of porcine aortic valve was numerically analyzed. The results show that: the flexible stent can decrease the maximum stress of leaflet, there is a suitable range of stent elastic behavior in which the maximum stress of leaflet is lower. For the same leaflet and the stent with same elastic modulus, the shape of stent with maximum stent top displacement is usually the best shape which can maximally decrease the maximum stress of leaflet comparing with the rigid stent.