A patient-specific aortic valve model based on moving resistive immersed implicit surfaces
A patient-specific aortic valve model based on moving resistive immersed implicit surfaces
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DOI：
10.1007/s10237-017-0919-1
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发表时间：
2017-10-01
影响因子：
3.5
通讯作者：
Quarteroni, Alfio
中科院分区：
文献类型：
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作者：
Fedele, Marco;Faggiano, Elena;Quarteroni, Alfio
在本文中，我们提出了一个完整的计算框架来模拟包括瓣膜在内的主动脉中的血液动力学。闭合和开放的瓣膜表面，以及主动脉腔，直接从医学图像重建使用新的特设算法，允许患者特定的模拟。从瓣膜的运动帐户的流体动力学问题是解决了一个新的3D-0 D流体-结构相互作用模型，其中的瓣膜表面是隐式表示通过水平集函数，产生，在Navier-Stokes方程，一个阻力惩罚项强制血液粘附到瓣叶。使用简化的几何0 D模型对阀在其关闭和打开位置之间的动态进行建模。在离散层次上，使用有限元公式，并将SUPG稳定化扩展到包括Navier-Stokes方程中的电阻项。然后，在时间离散化之后，通过交错方法耦合3D流体和0 D瓣膜模型。该计算框架应用于患者特定的几何形状和数据，允许模拟瓣膜的运动、跨瓣叶发生的急剧压力跳变以及主动脉内的血流模式。
In this paper, we propose a full computational framework to simulate the hemodynamics in the aorta including the valve. Closed and open valve surfaces, as well as the lumen aorta, are reconstructed directly from medical images using new ad hoc algorithms, allowing a patient-specific simulation. The fluid dynamics problem that accounts from the movement of the valve is solved by a new 3D-0D fluid-structure interaction model in which the valve surface is implicitly represented through level set functions, yielding, in the Navier-Stokes equations, a resistive penalization term enforcing the blood to adhere to the valve leaflets. The dynamics of the valve between its closed and open position is modeled using a reduced geometric 0D model. At the discrete level, a finite element formulation is used and the SUPG stabilization is extended to include the resistive term in the Navier-Stokes equations. Then, after time discretization, the 3D fluid and 0D valve models are coupled through a staggered approach. This computational framework, applied to a patient-specific geometry and data, allows to simulate the movement of the valve, the sharp pressure jump occurring across the leaflets, and the blood flow pattern inside the aorta.