De Hart J, Peters G W M, Schreurs P J G, Baaijens F P T
Department of Biomedical Engineering, Eindhoven University of Technology, Building W-hoog-4.117, PO Box 513, 5600 MB Eindhoven, The Netherlands.
J Biomech. 2003 Jan;36(1):103-12. doi: 10.1016/s0021-9290(02)00244-0.
Numerical analysis of the aortic valve has mainly been focused on the closing behaviour during the diastolic phase rather than the kinematic opening and closing behaviour during the systolic phase of the cardiac cycle. Moreover, the fluid-structure interaction in the aortic valve system is most frequently ignored in numerical modelling. The effect of this interaction on the valve's behaviour during systolic functioning is investigated. The large differences in material properties of fluid and structure and the finite motion of the leaflets complicate blood-valve interaction modelling. This has impeded numerical analyses of valves operating under physiological conditions. A numerical method, known as the Lagrange multiplier based fictitious domain method, is used to describe the large leaflet motion within the computational fluid domain. This method is applied to a three-dimensional finite element model of a stented aortic valve. The model provides both the mechanical behaviour of the valve and the blood flow through it. Results show that during systole the leaflets of the stented valve appear to be moving with the fluid in an essentially kinematical process governed by the fluid motion.
主动脉瓣的数值分析主要集中在舒张期的关闭行为，而非心动周期收缩期的运动学开闭行为。此外，在数值建模中，主动脉瓣系统中的流固相互作用常常被忽略。本文研究了这种相互作用对瓣膜收缩功能时行为的影响。流体和结构材料特性的巨大差异以及瓣叶的有限运动，使得血液-瓣膜相互作用建模变得复杂。这阻碍了对生理条件下运行的瓣膜进行数值分析。一种称为基于拉格朗日乘子的虚拟域方法的数值方法，被用于描述计算流体域内瓣叶的大幅运动。该方法应用于带支架主动脉瓣的三维有限元模型。该模型既提供了瓣膜的力学行为，也提供了通过瓣膜的血流情况。结果表明，在收缩期，带支架瓣膜的瓣叶似乎与流体一起运动，这一过程本质上是由流体运动控制的运动学过程。
