Fluid-structure interaction between pulsatile blood flow and a curved stented coronary artery on a beating heart: A four stent computational study
Fluid-structure interaction between pulsatile blood flow and a curved stented coronary artery on a beating heart: A four stent computational study
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DOI：
10.1016/j.cma.2019.03.034
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发表时间：
2019-06-15
影响因子：
7.2
通讯作者：
Wang, Yifan
中科院分区：
文献类型：
--
作者：
Bukac, Martina;Canic, Suncica;Wang, Yifan
这项工作的重点是弯曲（曲折）冠状动脉与植入支架，脉动血流和心脏收缩之间的流体结构相互作用（FSI）。目的是了解四种不同的市售支架几何形状的支架支柱几何分布最不可能与导致再狭窄的病理生物学反应相关参数相关，在弯曲冠状动脉的情况下，其曲率随每次心脏收缩而显著变化。本研究中考虑的支架几何形状对应于Palmaz-like支架、Pendulum-like支架、Cypher-like支架和Xience-like支架。根据位移幅度、Von Mises应力、植入支架的内膜层所承受的法向应力和壁面剪切应力，评价每枚植入支架诱导的生物力学环境。动脉壁被建模为多层结构：具有内部弹性层的内膜层被建模为非线性弹性膜，而中膜-外膜复合体被建模为3D线性弹性材料。不可压缩粘性流体的Navier-Stokes方程用于模拟血液流动。充分，双向耦合之间的流体和结构，薄和厚的结构，被认为是。为了包括由心包和心肌收缩施加的力的影响，外力被施加到冠状动脉壁。在冠状动脉段的入口和出口处施加脉动边界条件，近似测量的舒张期冠状动脉流量。植入支架的存在通过其对支架所在内膜层的质量和弹性特性的影响进行建模。支架材料建模为316 L不锈钢。一种新的，松散耦合的分区计划结合ALE方法来解决这个非线性流固耦合问题。发现Cypher样支架几何结构优于其他三种支架几何结构。从最好到最差的排序如下：Cypher类支架、Rheum-like支架、Xience类支架、Palmaz-like支架。据证实，与开孔设计相关的正弦水平支架支柱和大孔，产生了最符合自体弯曲冠状动脉的支架几何结构，在收缩期和舒张期，与未植入支架的弯曲冠状动脉的Von Mises应力和位移偏差最小。据我们所知，这是第一项计算研究，其中使用完整的FSI来研究植入弯曲冠状动脉中的不同支架几何形状的行为，捕获多层、弯曲、支架冠状动脉在跳动的心脏上收缩的行为。(C)2019爱思唯尔B. V.保留所有权利。
This work focuses on fluid-structure interaction (FSI) between a curved (tortuous) coronary artery with an implanted stent, pulsatile blood flow, and heart contractions. The goal is to understand which geometric distribution of stent struts, given by four different, commercially available stent geometries, is least likely to be associated with parameters correlated with pathobiologic responses leading to restenosis, in the case of curved coronary arteries, whose curvature changes significantly with each heart contraction. The stent geometries considered in this study correspond to a Palmaz-like stent, an Express-like stent, a Cypher-like stent, and a Xience-like stent. The biomechanical environment induced by each implanted stent is evaluated in terms of displacement magnitude, Von Mises stress, normal stress experienced by the intimal layer with implanted stent, and wall shear stress. Arterial walls are modeled as multi-layered structures: the intimal layer with the internal elastic laminae is modeled as a nonlinearly elastic membrane, while the media-adventitia complex is modeled as a 3D linearly elastic material. The Navier-Stokes equations for an incompressible, viscous fluid, are used to model the blood flow. Full, two-way coupling between the fluid and the structure, and between the thin and thick structure, is considered. To include the effects of the force exerted by the pericardium and heart muscle contractions, external force is applied to the coronary artery walls. Pulsatile boundary conditions were imposed at the inlet and outlet of the coronary segment, approximating measured diastolic coronary flow. The presence of an implanted stent was modeled by its impact on the mass and elasticity properties of the intimal layer where the stent is located. The stent material is modeled as a 316L stainless steel. A novel, loosely coupled partitioned scheme combined with an ALE approach was used to solve this nonlinear FSI problem. It was found that the Cypher-like stent geometry outperforms the other three stent geometries. The ranking from best to worst is as follows: Cypher-like stent, Express-like stent, Xience-like stent, Palmaz-like stent. It is conjectured that the sinusoidal horizontal stent struts and large cells associated with open-cell design, give rise to a stent geometry that conforms best to the native curved coronary artery, with smallest deviations in Von Mises stress and displacement from the nonstented curved coronary artery both during systole and diastole. To the best of our knowledge, this is the first computational study in which the behavior of different stent geometries implanted in curved coronary arteries is studied using full FSI capturing the behavior of multi-layered, curved, stented coronary arteries contracting on a beating heart. (C) 2019 Elsevier B.V. All rights reserved.