Computational Modeling of Mechanical Heart Valves

描述（由申请人提供）：人工心脏瓣膜（PHV）已使用超过4年 几十年来更换患病的心脏瓣膜。然而，目前的设计远非理想， 严重的并发症，如溶血，血小板破坏，血栓栓塞， 他们的植入，需要积极的终身抗凝治疗，这反过来又带来严重的 副作用.然而，改进目前的PHV设计需要高度精确的流量量化， 由于PHV的复杂和错综复杂的几何形状， 缺乏适当的计算方法来解决PHV流的复杂性。小说 流固耦合计算流体动力学（CFD）工具已经在当前得到了成功的开发和验证 格兰特.沿着大量的实验研究，这一数值工具首次深入研究了 了解生理条件下PHV流动的复杂物理学和血流动力学相关尺度。拟议的竞争性续约采取了下一步， 实现了用于改进人工瓣膜设计的计算框架的开发， 患者的具体基础。当前的磁共振成像（MRI）技术使得有可能 以足够高的分辨率获得完整的3D移动几何形状，以规定主动脉和心室壁 运动作为数值模型的边界条件。通过结合高分辨率CFD技术 随着MRI技术的最新进展， 可以为PHV接受者开发动态分析工具。 推动这种竞争性更新的总体假设是：高分辨率，基于成像的计算 流体动力学（CFD）建模可用于开发可行的患者特定血液动力学工具 其中心脏装置（不仅限于心脏瓣膜假体）可以在患者 治疗这一假设将在以下四个目标中得到解决： 目标1：开发左心室/主动脉构型的CFD工具 目的2：在体模左心室/主动脉配置中进行确认的体外实验， 边界 目的3：开发用于重建解剖学上精确的运动心室的图像处理方法 和主动脉的几何形状 目标4：初步应用计算工具进行患者模拟和分析 该项目的成功将导致心脏瓣膜流量分析领域的重大进步， 开发流体机械改进的心脏装置。公共卫生相关性： 目前人工心脏瓣膜的设计远不理想，并且存在严重的并发症风险，需要患者经历积极的终身抗凝治疗，这反过来又带来了并发症。 额外的风险。在这场竞争性的更新中，在最初的时代产生的计算技术 Grant被进一步开发以能够模拟患者特定解剖结构中的流动。这将是 通过使用磁共振成像获得患者的实际几何形状并将该信息与当前计算流体的更复杂和改进的版本相结合来实现 动力学软件

DESCRIPTION (provided by applicant): Prosthetic heart valves (PHV) have been in use for over four decades to replace diseased heart valves. However, present-day designs are far from ideal and significant complications such as hemolysis, plateletdestruction, and thromboembolism often arise after their implantation, requiring aggressive life long anticoagulation therapy which in turn carries serious side effects. Improving current PHV designs, however, needs highly accurate flow quantification - a task not achievable until recently due to the complex and intricate geometries of PHVs combined with the lack of an appropriate computational methodology to tackle the complexities of PHV flows. Novel fluid-structure interaction CFD tools have been successfully developed and validated in the current grant. Along with numerous experimental studies, this numerical tool has yielded the first ever in depth understanding of the complex physics of PHV flows under physiological conditions and at hemodynamically relevant scales. The proposed competing renewal takes the next step towards achieving the development of a computational framework for improving valve prosthesis designs on a patient-specific basis. Current Magnetic Resonance Imaging (MRI) technology makes it possible to obtain full 3D moving geometries at resolution sufficiently high to prescribe aorta and ventricular wall motions as boundary conditions for the numerical model. By coupling high resolution CFD techniques with the latest advancements in MRI technology, a powerful and clinically useful hemodynamic/fluid dynamic analysis tool could be developed for the benefit of PHV recipients. The overall hypothesis driving this competing renewal is: High resolution, imaging-based Computational Fluid Dynamics (CFD) modeling can be used to develop viable patient-specific hemodynamic tools where cardiac devices (not only limited to heart valve prostheses) may be evaluated prior to patient treatment. This hypothesis will be addressed in the following four aims: Aim 1: Development of CFD tools for left ventricle/aorta configuration Aim 2: In vitro experiments for validation in a phantom left ventricle/aorta configuration with moving boundaries Aim 3: Develop image processing methods for reconstruction of anatomically accurate moving ventricle and aorta geometries Aim 4: Preliminary application of the computational tools for patient simulation and analysis Completion of this project will lead to a significant advancement in the field of heart valve flow analysis and the development of fluid mechanically improved cardiac devices. PUBLIC HEALTH RELEVANCE: Present day designs of prosthetic heart valves are far from ideal and significant risk of complications exist requiring patients to undergo aggressive life long anti-coagulation therapy which in turn carries additional risks. In this competing renewal, the computational technology produced during the original grant is further developed to be able to simulate flows in patient specific anatomies. This will be achieved by obtaining actual geometries of patients using magnetic resonance imaging and coupling this information with a more sophisticated and improved version of the current computational fluid dynamics software.