Engineering Analysis of Minimally Invasive Mitral Valve Repair

描述(由申请人提供)：本次研究培训奖学金的目的是为候选人提供一个独特的机会，学习心脏瓣膜疾病的跨学科知识及其使用工程工具进行治疗。应聘者将学习如何应用工程力学原理、计算技术和生物医学科学来解决与心脏瓣膜疾病治疗相关的临床问题。为了完成这一培训计划，候选人将进行研究，通过实验和计算相结合的研究，调查微创二尖瓣修复涉及的生物力学，以更好地了解瓣膜修复的潜在机制，并促进新型介入设备的设计。具体地说，将实现以下具体目标：1)量化冠状静脉窦(CS)/心大静脉(GCV)、二尖瓣组织以及邻近心肌的弹性特性。2)利用本构模型对组织特性进行精确建模。3)利用人体心脏和心脏CT图像建立二尖瓣装置的三维有限元模型，并对有限元模型进行验证。方法：候选人将进行一系列实验来表征二尖瓣组织的特性。将进行组织学分析，以研究组织的微观结构，并了解组织结构与功能的关系。严格的应变能函数将被应用于精确的组织属性建模，该模型将被并入有限元模拟。相关组织的3D几何形状将从切除的心脏和心脏图像的物理测量中重建。进行模型误差估计，并通过与实验数据的比较，对仿真结果进行验证。取得的成果将是：1)建立生物力学性能、几何形状和有限元模型数据库，用于分析微创二尖瓣修复治疗；2)候选人将获得广泛的培训和对心血管生物力学，特别是与心脏瓣膜疾病相关的力学的深入了解。 公共卫生相关性：这项研究与二尖瓣疾病的微创治疗有关，特别是对不能接受心脏直视手术的高危患者。这项研究的结果将为更好的设备设计和瓣膜疾病治疗提供见解。

DESCRIPTION (provided by applicant): The purpose of this research training fellowship is to provide the candidate with a unique opportunity to learn the interdisciplinary knowledge of heart valve disease and its treatment using engineering tools. The candidate will learn how to apply engineering mechanics principles, computational technologies and biomedical sciences to solve clinical issues related to heart valve disease treatment. To accomplish this training plan, the candidate will conduct research to investigate the biomechanics involved in minimally invasive mitral valve repair, through a combined experimental and computational study, to better understand underlying valve repair mechanisms, and to facilitate novel intervention device design. Specifically, the following specific aims will be achieved: 1) Quantify the elastic properties of coronary sinus (CS)/great cardiac vein (GCV), and mitral valve tissues as well as adjacent myocardium. 2) Utilize constitutive models to accurately model tissue properties. 3) Generate 3D Finite Element (FE) models of the mitral valve apparatus from excised human hearts and cardiac CT images, and validate the FE models. Methods: The candidate will perform a series of experiments to characterize mitral tissue properties. Histology analysis will be conducted to study the microstructures of tissues and to understand tissue structure-function relations. A rigorous strain energy function will be applied to accurately model the tissue properties, which will in turn be incorporated into FE simulations. 3D geometries of associated tissues will be recreated from physical measurements of excised hearts and cardiac images. Model error estimation will be performed and simulation results will be validated through comparison with experiment data. The achievements will be 1) the establishment of databases of biomechanical properties, geometries and FE models for analyzing minimally invasive mitral valve repair treatment; 2) the candidate will gain extensive training and an in-depth understanding of the cardiovascular biomechanics, especially the mechanics related to heart valve disease. PUBLIC HEALTH RELEVANCE: This research is relevant to a minimally invasive treatment of mitral valve disease, in particular for high-risk patients who cannot undergo open-heart surgery. Findings of this study will offer insights for better device designs and valve disease treatments.