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

心脏是我们最重要、最复杂的器官之一。心脏的四个腔室和四个阀门通过电动力学和机械动力学（包括固体和流动）的相互作用，密切配合，完成充盈、弹射和整体泵送功能。对这些动态及其耦合进行建模对于理解这些复杂现象非常重要。目前的计算模型虽然能够计算电固耦合力学或固流耦合力学，但由于其有限的建模灵活性与所涉及的复杂物理过程之间的冲突，在集成三种动力学方面存在严重困难。当前项目的长期目标是开发一种心脏模拟器，具有改善心脏病治疗的潜力。在第一个3年的资助期内，我们取得了丰硕的成果，这代表了我们在开发统一的基于sph的人类全心功能模型方面取得了实质性的进展。我们在心脏传导系统和瓣膜的计算效率建模方面也遇到了挑战，以及GPU加速问题，但在我们最近的成就中已经有效地解决了这些问题。在第二个3年的资助期内，我们将继续研究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整合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对全功能进行数值模拟，并探索其可能的临床应用。

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.