主动脉瓣部分关闭和完全开放的有限元分析

目的 探究不同的初始状态设置对瓣膜仿真计算的影响。方法 创建初始状态分别为主动脉瓣部分关闭和完全开放的二维结构模型，对瓣膜和主动脉侧、心室侧的血管壁施加随时间变化的压力载荷，采用有限元法研究在两种不同初始状态设置下瓣膜关闭时的最大应力、对合长度和接触力。结果 以完全开放为初始状态的模型在瓣膜关闭时的应力和接触力更大，瓣膜闭合程度较差，周期性循环中应力和闭合程度的变化较大；部分关闭为初始状态下瓣膜在关闭时的应力和接触力小，闭合程度较好，周期性循环中应力和闭合程度的变化小。结论 在初始状态为部分关闭时，计算过程的稳定性和瓣膜的闭合程度较好，在进行数值模拟计算时可以给予更多的考虑。研究结果可为瓣膜和主动脉根部生物力学机制的研究提供参考。
Objective To explore the effect of different initial state setting on a valve simulation. Methods Two-dimensional structural models were established with the initial state of the aortic valve being partially closed in one model and fully opened in the other. The time-dependent load was applied to the valve and the vessel wall of the aortic and the ventricle sides. The finite element method was used to study the maximum stress, the length of the joint, and the contact force of the closed aortic valve under two different initial states. Results The stress and contact force of the aortic valve were relatively large at the closed position when the initial state was fully opened. The closure degree of the valve was low, and the variations in stress and closure degree were large during the periodic cycle. The stress and contact force of the valve were relatively small when the aortic valve was partially closed. The closure degree was high, and the variations in stress and closure degree of the aortic valve were small during the periodic cycle. Conclusions In the case of the aortic valve partially closed in the initial state, the stability of the calculation process and the closure degree of the valve were relatively high, which should be given more consideration in numerical simulation. The results can be used to study the mechanical behavior of the valve and the biomechanical mechanism of the aortic root.