COMPUTATIONAL METHODS IN CARDIAC FLUID DYNAMICS

这个项目的主要目标是开发三个- 三维心脏模拟器：心脏的计算机模型，其 阀门和附近的大型容器。心脏模拟器将 使心脏研究的一种新模式成为可能，计算机 实验中，调查者可以完全控制 每个单独的实验变量并完全访问所有 实验数据作为输出(在 模拟测量和模拟实验)。 为了测试心脏模拟器，同时 阐明诊断心脏成像的某些方面， 该项目包括模拟彩色多普勒血流成像的计划， 超声心动图、对比血管造影术、核医学(门控 血池)成像，可能还有磁共振成像。至 模拟图像与相应图像的一致性程度 这将为临床图像的有效性提供支持 模特。此外，如果有这样的约定，就可以使用已知的 在模拟案例中增强底层情境的实用性 诊断技术的最新进展。 拟议的心脏模拟器计划在三年内应用 主要领域：(1)人工心脏瓣膜的设计，(2) 影响关节机械功能的疾病的计算机模型 心脏或心脏瓣膜的研究；(3)正常生理学和 功能解剖学。在人工瓣膜设计中，参数 研究计划中心脏模拟器将被用于 根据压降、净值优化阀门性能 每搏出血量和血栓形成。疾病的计算机模型 过程将包括瓣膜病理，如狭窄和 反流，涉及瓣膜的特定症状，如 二尖瓣脱垂综合征与特发性肥厚 主动脉瓣下狭窄和室壁运动异常的情况 比如室壁瘤。在功能解剖学领域 和生理学，计划进行研究以阐明正常 心脏的功能。这样的研究将基于系统的 心脏参数在正常值附近的变异 观察对心功能的影响。这项工作应该揭示 在实际设计中可能有用的“设计”原则 人造心脏。生理学领域的另一项计划研究 与心脏的急性和慢性适应有关 锻炼身体。除了其内在的兴趣，这项研究还将 使我们有可能在运动状态下测试人工瓣膜 条件。上述工作都涉及到 成人心脏。此外，该项目还涉及一系列研究 与心脏发育和儿科心脏病学有关。这些 包括对心脏流动模式的计算机实验 在不同的发展阶段，模拟了 心脏在出生时发生，以及计算机模型的发展 患有先天性心脏病。

The principal goal of this project is to develop a three- dimensional cardiac simulator: a computer model of the heart, its valves, and the nearby great vessels. The cardiac simulator will make possible a new mode of cardiac investigation, the computer experiment, in which the investigator has complete control over each individual experimental variable and complete access to all experimental data as output (without any interference between the simulated measurement and the simulated experiment). In order to test the cardiac simulator and simultaneously to elucidate certain aspects of diagnostic cardiac imaging, the project includes plans to simulate color-Doppler flow imaging, echocardiography, contrast angiography, nuclear medicine (gated blood-pool) imaging, and possibly magnetic resonance imaging. To the extent that the simulated images agree with the corresponding clinical images, this will provide support for the validity of the model. Given such agreement, moreover, one can use the known underlying situation in the simulated case to enhance the utility of the diagnostic technique. Applications of the proposed cardiac simulator are planned in three principal areas: (1) design of prosthetic cardiac valves, (2) computer models of diseases affecting mechanical function of the heart or its valves, and (3) studies on normal physiology and functional anatomy. In prosthetic valve design,, parametric studies are planned in which the cardiac simulator will be used to optimize valve performance with respect to pressure drop, net stroke volume, and thrombogenesis. Computer models of disease processes will include valve pathology such as stenosis and regurgitation, specific syndromes involving the valves such as Mitral Valve Prolapse Syndrome and idiopathic Hypertrophic Subaortic Stenosis, and conditions in which wall motion abnormal such as ventricular aneurism. In the area of functional anatomy and physiology, studies are planned to elucidate the normal function of the heart. Such studies will be based on systematic variation of cardiac parameters about their normal values to observe the effect on cardiac function. This work should reveal "design" principles which may be useful in the actual design of artificial hearts. Another planned study in the area of physiology is concerned with the acute and chronic adaptation of the heart to exercise. Aside from its intrinsic interest, this study will also make it possible for us to test prosthetic valves under exercise conditions. The work described above is all concerned with the adult heart. In addition, the project involves a series of studies related to cardiac development and pediatric cardiology. These include computer experiments on the flow pattern of the heart at different stages of development, simulation of the changes in the heart occurring at birth, and the development of computer models of congenital heart disease.