Pulsatile flow simulation in arterial vascular segments with intravascular ultrasound images
Pulsatile flow simulation in arterial vascular segments with intravascular ultrasound images
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DOI：
10.1016/s1350-4533(01)00088-1
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发表时间：
2001-10-01
影响因子：
2.2
通讯作者：
Chandran, KB
中科院分区：
文献类型：
--
作者：
Liu, Y;Lai, Y;Chandran, KB
先前的研究表明动脉血流中壁切应力的局部变化与动脉粥样硬化的发展之间存在相关性。本研究的目的是从形态逼真的三维（3D）重建血管段的血流动力学分析。并比较在顺应性血管段模型和相应的刚性壁模型中计算的壁剪切应力。使用血管内超声（IVUS）成像获得了5只尤卡坦小型猪股动脉和颈动脉段的横截面图像，并在心动周期的不同时间重建了该段的几何形状。从重建的实际测量的室壁运动被用来指定用于模拟生理扩张性的移动边界。采用非定常计算流体动力学方法计算了壁面速度分布和壁面切应力。计算结果表明，当壁面运动大于10%时，柔性模型的最大壁面切应力比刚性模型的最大壁面切应力约小4%~ 17%。我们的分析表明，由于入流速度剖面的不准确性可以最大限度地减少模型的上游扩展。直径变化和壁剪切之间的相位角受动脉几何形状的局部变化的影响。这些模拟可以潜在地用于分析在动脉粥样硬化病变的存在下局部室壁运动变化对局部流体动力学的影响，并将其与病变的后续生长相关联。(C)2001年妇女平等研究所。由爱思唯尔科技有限公司出版。保留所有权利。
Previous studies have indicated a correlation between local variation in wall shear stress in arterial blood flow and atheroma development. The purpose of this study was to analyze the hemodynamics in vascular segments from morphologically realistic three-dimensional (3D) reconstruction. and to compare the computed wall shear stress in a compliant vascular segment model and the corresponding rigid walled model. Cross-sectional images of the segments of femoral and carotid arteries in five Yucatan miniswine were obtained using intravascular ultrasound (IVUS) imaging and the segment geometry was reconstructed at different times in the cardiac cycle. The actual measured wall motion from the reconstruction was employed to specify the moving boundaries for simulation of physiological distensibility. Velocity profiles and wall shear stress were computed using unsteady computational fluid dynamics analysis, The computed results revealed that the maximum wall shear stress in the compliant model was approximately 4-17 percent less than that in the rigid model if the wall motion is larger than 10 percent. Our analysis demonstrates that inaccuracies due to inflow velocity profile can be minimized by the extension of the model upstream. The phase angle between the diameter change and wall shear is affected by the local changes in geometry of the arteries. These simulations can be potentially used to analyze the effect of regional wall motion changes in the presence of atherosclerotic lesions on the local fluid dynamics and to correlate the same with subsequent growth of the lesions. (C) 2001 IPEM. Published by Elsevier Science Ltd. All rights reserved.