Computational study of fluid mechanical disturbance induced by endovascular stents
Computational study of fluid mechanical disturbance induced by endovascular stents
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DOI：
10.1007/s10439-005-2499-y
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发表时间：
2005-04-01
影响因子：
3.8
通讯作者：
Barakat, AI
中科院分区：
文献类型：
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作者：
Seo, T;Schachter, LG;Barakat, AI
支架展开后的动脉再狭窄可能受到支架内和周围的局部血流环境的影响。我们使用计算流体动力学来研究位于直血管和弯曲血管内的模型支架附近的流场。我们的模拟揭示了支架紧下游存在流动分离和再循环。在直血管内的稳定流动中，支架下游的流动扰动程度随着雷诺数和支架线材厚度的增加而增加，但对支架线材间距相对不敏感。在弯曲的血管中，支架下游的流动扰动沿着内血管壁和外血管壁发生，扰动的程度取决于血管曲率的角度。在脉动流中，流动扰动区域的尺寸周期性地增大和减小。非牛顿流体特性导致支架下游的流动扰动适度减少。在更现实的支架几何形状中，例如建模为螺旋或交织环的支架，支架引起的流动扰动的性质对支架设计非常敏感。这些结果提供了对支架附近流动物理学的理解，并提出了支架设计优化策略以最小化流动扰动。
Arterial restenosis following stent deployment may be influenced by the local flow environment within and around the stent. We have used computational fluid dynamics to investigate the flow field in the vicinity of model stents positioned within straight and curved vessels. Our simulations have revealed the presence of flow separation and recirculation immediately downstream of stents. In steady flow within straight vessels, the extent of flow disturbance downstream of the stent increases with both Reynolds number and stent wire thickness but is relatively insensitive to stent interwire spacing. In curved vessels, flow disturbance downstream of the stent occurs along both the inner and outer vessel walls with the extent of disturbance dependent on the angle of vessel curvature. In pulsatile flow, the regions of flow disturbance periodically increase and decrease in size. Non-Newtonian fluid properties lead to a modest reduction in flow disturbance downstream of the stent. In more realistic stent geometries such as stents modeled as spirals or as intertwined rings, the nature of stent-induced flow disturbance is exquisitely sensitive to stent design. These results provide an understanding of the flow physics in the vicinity of stents and suggest strategies for stent design optimization to minimize flow disturbance.