Osouli Kasra, De Gaetano Francesco, Costantino Maria Laura, Peirlinck Mathias
Department of Chemistry, Materials and Chemical Engineering, Politecnico di Milano, Milan, Italy.
Department of BioMechanical Engineering, Faculty of Mechanical Engineering, Delft University of Technology, Delft, The Netherlands.
Biomech Model Mechanobiol. 2025 Oct;24(5):1815-1835. doi: 10.1007/s10237-025-01995-y. Epub 2025 Sep 3.
The intricate three-dimensional organization of cardiac myofibers and sheetlets plays a critical role in the mechanical behavior of the human heart. Despite extensive research and the development of various rule-based myofiber architecture surrogate models, the precise arrangement of these structures and their impact on cardiac function remain subjects of debate. In this study, we present a novel myofiber architecture surrogate inspired by Streeter's nested tori conjecture, modeling the left ventricle as a series of smoothly twisting toroidal surfaces populated by continuous myofiber and sheetlet fields. Leveraging high-fidelity cardiac computational modeling approaches, we systematically evaluated the biomechanical performance of this nested tori architecture against conventional rule-based nested ellipsoidal models. Our results demonstrate that the nested tori architecture aligns more closely with experimental data on physiological myofiber and sheetlet angles. Notably, it enhances sheetlet mobility-a key mechanism for effective cardiac pumping-resulting in higher ejection fraction, greater global deformation, and a more physiological wall rotation pattern. Additionally, it produces a more homogeneous myofiber stress distribution and increased myofiber shortening during ejection. These findings suggest that the nested tori architecture provides a compelling alternative to conventional nested ellipsoidal models, offering a more physiologically consistent representation of myocardial structure and its functional implications. By enabling improved biomechanical performance in silico, this approach supports further investigation into how detailed myoarchitectural continuity shapes cardiac function. Ultimately, it may open promising avenues for advancing cardiac diagnosis, guiding the design of bioinspired implants and devices, and deepening our understanding of both healthy and diseased cardiac mechanics.
心肌纤维和心肌薄片复杂的三维组织结构在人类心脏的力学行为中起着关键作用。尽管进行了广泛的研究并开发了各种基于规则的心肌纤维结构替代模型，但这些结构的精确排列及其对心脏功能的影响仍然存在争议。在本研究中，我们提出了一种受斯特里特嵌套环面猜想启发的新型心肌纤维结构替代模型，将左心室建模为一系列由连续的心肌纤维和心肌薄片场构成的平滑扭曲的环面。利用高保真心脏计算建模方法，我们系统地评估了这种嵌套环面结构相对于传统基于规则的嵌套椭球模型的生物力学性能。我们的结果表明，嵌套环面结构与生理心肌纤维和心肌薄片角度的实验数据更为吻合。值得注意的是，它增强了心肌薄片的流动性——这是有效心脏泵血的关键机制——从而导致更高的射血分数、更大的整体变形以及更符合生理的壁旋转模式。此外，它还产生了更均匀的心肌纤维应力分布，并在射血过程中增加了心肌纤维的缩短。这些发现表明，嵌套环面结构为传统的嵌套椭球模型提供了一个引人注目的替代方案，为心肌结构及其功能意义提供了更符合生理的表示。通过在计算机模拟中实现更好的生物力学性能，这种方法支持进一步研究详细的心肌结构连续性如何塑造心脏功能。最终，它可能为推进心脏诊断、指导生物启发式植入物和设备的设计以及加深我们对健康和患病心脏力学的理解开辟有前景的途径。
