Fluid-structure interaction models of the mitral valve: function in normal and pathological states
Fluid-structure interaction models of the mitral valve: function in normal and pathological states
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DOI：
10.1098/rstb.2007.2123
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发表时间：
2007-08-29
影响因子：
6.3
通讯作者：
Cochran, R. P.
中科院分区：
文献类型：
--
作者：
Kunzelman, K. S.;Einstein, D. R.;Cochran, R. P.
成功的二尖瓣修复取决于对正常和异常二尖瓣解剖结构和功能的充分理解。计算分析就是这样一种方法，可用于模拟二尖瓣功能，以分析单个组件的作用并评价拟议的手术修复。我们开发了二尖瓣的第一个三维有限元计算机模型，包括瓣叶和腱索;然而，直到最近几年，一个关键方面一直缺失，即与二尖瓣结构功能相结合的流体流动评价。我们在这里提出我们的最新结果正常功能和特定的病理变化，使用流体-结构相互作用模型。首先评估正常瓣膜功能，然后评估胶原纤维体积分数、纤维刚度、纤维张开和各向同性刚度的病理材料变化。测定瓣叶和腱索应力和应变以及乳头肌力。此外，还评估了跨瓣血流、瓣叶关闭时间和心脏瓣膜声音。在正常状态下的模型预测同意与广泛的可用的体内和体外数据。此外，发现保留瓣叶各向异性的病理材料变化可保留瓣膜功能。相比之下，发现改变瓣膜各向异性的材料变化会深刻改变瓣膜功能。血流的增加和实验驱动的二尖瓣组织的微观结构描述代表了二尖瓣的计算研究的重大进展，这允许获得进一步的见解。这项工作是计算框架基础的另一个构建块，有助于完善和开发二尖瓣的真正无创诊断评价。最终，它代表了在临床和教育环境中模拟病理瓣膜手术修复的基础。
Successful mitral valve repair is dependent upon a full understanding of normal and abnormal mitral valve anatomy and function. Computational analysis is one such method that can be applied to simulate mitral valve function in order to analyse the roles of individual components and evaluate proposed surgical repair. We developed the first three-dimensional finite element computer model of the mitral valve including leaflets and chordae tendineae; however, one critical aspect that has been missing until the last few years was the evaluation of fluid flow, as coupled to the function of the mitral valve structure. We present here our latest results for normal function and specific pathological changes using a fluid-structure interaction model. Normal valve function was first assessed, followed by pathological material changes in collagen fibre volume fraction, fibre stiffness, fibre splay and isotropic stiffness. Leaflet and chordal stress and strain and papillary muscle force were determined. In addition, transmitral flow, time to leaflet closure and heart valve sound were assessed. Model predictions in the normal state agreed well with a wide range of available in vivo and in vitro data. Further, pathological material changes that preserved the anisotropy of the valve leaflets were found to preserve valve function. By contrast, material changes that altered the anisotropy of the valve were found to profoundly alter valve function. The addition of blood flow and an experimentally driven microstructural description of mitral tissue represent significant advances in computational studies of the mitral valve, which allow further insight to be gained. This work is another building block in the foundation of a computational framework to aid in the refinement and development of a truly non-invasive diagnostic evaluation of the mitral valve. Ultimately, it represents the basis for simulation of surgical repair of pathological valves in a clinical and educational setting.