人体二尖瓣建模及生物力学分析  

Numerical modeling and biomechanical analysis of the human mitral valve

作　　者：钟琪[1] 曾文华[2] 黄晓阳[3] 王博亮[3] 

机构地区：[1]厦门大学信息科学与技术学院,智能科学与技术系,厦门361005 [2]厦门大学软件学院,厦门361005 [3]厦门大学信息科学与技术学院,计算机科学系,厦门361005

出　　处：《医用生物力学》2014年第1期53-59,共7页Journal of Medical Biomechanics

基　　金：国家自然科学基金资助项目(61102137);福建省自然科学基金资助项目(2011J01366);福建省创新医学科研基金(2009-CXB-59)

摘　　要：目的建立人体心脏二尖瓣仿真模型,模拟二尖瓣闭合的工作过程,分析二尖瓣各组件应力分布,探讨二尖瓣瓣叶和腱索的相互作用,并探寻腱索受力大小与腱索粗细之间的相关性。方法构建二尖瓣几何模型,在此基础上定义模型单元类型、材料属性、接触、载荷及约束,建立有限元模型,计算模型的应力、速度和位移等参数。结果瓣膜上的应力分布不均匀,后瓣叶亚区之间的裂口位置所受应力最大;不考虑腱索连接至瓣叶时,瓣叶负载后外翻至心房一侧;考虑腱索连接至瓣叶时,前、后瓣叶关闭良好;各腱索受力不同,与前瓣叶相连的支持腱索受力最大,腱索受力大小与腱索粗细之间的线性相关系数为0.954。结论瓣叶中心和后瓣叶亚区之间的裂口两处应力较大区域是临床上二尖瓣裂的常发生部位;与瓣叶相连的腱索可在瓣叶负载时,施加牵拉力使瓣叶不致发生翻转,前、后瓣叶恰好关闭;解剖结构粗壮的腱索受力较大。Objective To establish a numerical model of human mitral valve and simulate its closing process, so as to analyze stress distributions on the valve apparatuses, study the interaction between leaflets of mitral valve and chordae tendineae, and explore the relationship between the force of chordae tendineae and their thickness. Methods A geometric model of human mitral valve was constructed. On the basis of the geometric model, the finite element model was established by defining the element type, material attributes, contacts, loads and constraints. Parameters such as stress, velocity and displacement were calculated after solving the model. Results The stress distribution on the valve was non-uniform. The clefts between the scallops in the posterior leaflet were always under the highest load. When no chordae tendineae were attached, the leaflets turned over to the side of the atrium. When chordea tendineae were attached, the anterior and posterior leaflet could close up successfully. Different chordae tendineae applied different forces to the valve. The strut chorea tendineae attached to the anterior leaflet applied highest force among all the chordea tendineae. The correlation coefficient between the thickness of chordae tendineae and their force was 0.954. Conclusions The two zones with higher stresses, namely the center of the leaflet and the clefts between the three scallops in the posterior leaflet, are also the positions of mitral valve cleft in clinic. Chordea tendineae can apply the pulling force on the leaflets while the mitral valve is under load, thus the leaflets won’t turn over to the side of atrium and the valve can close up in time. Chordea tendineae with thicker anatomic structure always apply a higher force on the leaflets.

关 键 词：二尖瓣 腱索 瓣叶 应力分布 有限元分析 

分 类 号：R318.01[医药卫生—生物医学工程]