Cardiac fluid dynamics fundamentally involves interactions between complex blood flows and the structural deformations of the muscular heart walls and the thin, flexible valve leaflets. There has been longstanding scientific, engineering, and medical interest in creating mathematical models of the heart that capture, explain, and predict these fluid-structure interactions. However, existing computational models that account for interactions among the blood, the actively contracting myocardium, and the cardiac valves are limited in their abilities to predict valve performance, resolve fine-scale flow features, or use realistic descriptions of tissue biomechanics. Here we introduce and benchmark a comprehensive mathematical model of cardiac fluid dynamics in the human heart. A unique feature of our model is that it incorporates biomechanically detailed descriptions of all major cardiac structures that are calibrated using tensile tests of human tissue specimens to reflect the heart's microstructure. Further, it is the first fluid-structure interaction model of the heart that provides anatomically and physiologically detailed representations of all four cardiac valves. We demonstrate that this integrative model generates physiologic dynamics, including realistic pressure-volume loops that automatically capture isovolumetric contraction and relaxation, and predicts fine-scale flow features. None of these outputs are prescribed; instead, they emerge from interactions within our comprehensive description of cardiac physiology. Such models can serve as tools for predicting the impacts of medical devices or clinical interventions. They also can serve as platforms for mechanistic studies of cardiac pathophysiology and dysfunction, including congenital defects, cardiomyopathies, and heart failure, that are difficult or impossible to perform in patients.

翻译：心脏流体动力学从根本上涉及复杂血流与肌肉心壁及薄而灵活的瓣叶结构变形之间的相互作用。长期以来，在科学、工程和医学领域，人们一直致力于建立能够捕捉、解释和预测这些流固耦合作用的心脏数学模型。然而，现有考虑血液、主动收缩心肌及心脏瓣膜相互作用的计算模型，在预测瓣膜性能、解析精细尺度流动特征或采用组织生物力学真实描述方面存在局限。本文介绍并验证了一个全面的人体心脏流体动力学数学模型。该模型的独特之处在于，它整合了所有主要心脏结构的生物力学详细描述，并通过人体组织样本拉伸试验进行校准，以反映心脏的微观结构。此外，这是首个为所有四个心脏瓣膜提供解剖学和生理学详细表征的心脏流固耦合模型。我们证明，该整合模型能够产生生理动力学行为，包括自动捕捉等容收缩和舒张的真实压力-容积环，并预测精细尺度流动特征。这些输出结果均非预设，而是从我们对心脏生理学的全面描述中涌现出的相互作用。此类模型可作为预测医疗设备或临床干预影响的工具，也可作为难以或无法在患者身上进行的心脏病理生理学及功能障碍（包括先天性缺陷、心肌病和心力衰竭）机理研究平台。