Unified computational modeling of the total human heart function with smoothed particle hydrodynamics

心脏是我们最重要和最复杂的器官之一。心脏的四个腔室和四个瓣膜通过电动力学和机械动力学（包括固体和流动）的相互作用紧密合作以实现填充、喷射和整体泵送功能。目前的计算模型虽然能够计算电-固耦合或固-流耦合动力学，但由于建模灵活性有限与涉及的物理过程复杂之间的矛盾，使得它们在集成所有三种动力学方面存在严重困难。目前项目的长期目标是开发一种有潜力改善心脏病治疗的心脏模拟器。在第一个三年的资助期内，我们取得了丰硕的成果，这代表着在开发基于SPH的统一人体心脏功能模型方面取得了实质性进展。我们也遇到了心脏传导系统和瓣膜的计算效率建模的挑战，以及GPU加速的问题，但在我们最近的成就中有效地解决了这些问题。在第二个3年的资助期内，我们将继续致力于心脏传导系统与肌肉激活的耦合，瓣膜的建模及其与流体动力学的耦合。然后，我们将开发的模型和算法集成到基于工作站的全功能心脏模拟器中，利用解剖高分辨率心脏模型进行全心脏功能的数值模拟，并探索可能的临床应用。

The heart is one of our most vital and most complex organs. The four chambers and four valves of the heart cooperate closely for filling, ejecting, and the overall pumping function by the interaction of electrical and mechanical (including solids and flow) dynamics.Modeling these dynamics and their coupling is important for understanding these complex phenomena. While the current computational models are able to compute the coupled electrical and solid mechanics or the coupled solid and fluid mechanics, they suffer from serious difficulties on integrating all the three dynamics due to the conflicts between their limited modeling flexibility and the complex physical processes involved. The long-term objective of the current project is to develop a heart simulator with the potential to improve the treatment for heart disease. In the first funding period of 3 years, we achieved fruitful achievements, which represents the substantial progresses towards developing unified SPH-based model for total human heart function. We have also encountered challenges in computationally efficient modeling of the cardiac conduction system and valves, as well as issues with GPU acceleration, but have effectively addressed them in our recent accomplishments.In the second funding period of 3 years, we will continue to work on coupling of cardiac conduction system with muscle activation, modeling of valves and their coupling with fluid dynamics. Then, we will integrate the developed models and algorithms into workstation-based total-function heart simulator, carry out numerical simulations of the total heart function with anatomical high-resolution heart models and explore the possible clinical applications.