Investigation of hemodynamics in the development of dissecting aneurysm within patient-specific dissecting aneurismal aortas using computational fluid dynamics (CFD) simulations
Investigation of hemodynamics in the development of dissecting aneurysm within patient-specific dissecting aneurismal aortas using computational fluid dynamics (CFD) simulations
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DOI：
10.1016/j.jbiomech.2010.12.014
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发表时间：
2011-03-15
影响因子：
2.4
通讯作者：
Ho, Pei
中科院分区：
文献类型：
--
作者：
Tse, Kwong Ming;Chiu, Peixuan;Ho, Pei
主动脉夹层动脉瘤是最严重的心血管急症之一，死亡率高。从临床观察中指出，动脉瘤的发展可能与夹层主动脉的血流动力学状况有关。为了更深入地了解夹层动脉瘤的形成和发展，血流动力学参数，包括流动模式，速度分布，主动脉壁压力和剪切应力，这是很难在体内测量，使用数值模拟进行评估。通过计算流体动力学（CFD）模拟研究了腔内动脉瘤形成前后（动脉瘤前和动脉瘤后）患者特定夹层动脉瘤中的脉动血流。在完整的主动脉模型的各个动脉处规定了与时间相关的真实边界条件。本研究提示，主动脉内血流的螺旋性可能与真腔周围假腔的螺旋状发展有关。主动脉狭窄是导致管腔动脉瘤发展中狭窄后区域大量再循环的原因。前降主动脉真假腔间0.21 kPa的高压差提示降主动脉腔内可能存在动脉瘤。还发现，相对高的时间平均壁剪切应力（在4-8 kPa的范围内）可能与撕裂的引发和扩展相关联。CFD建模通过提供血流模式、壁压和壁剪切应力来辅助医疗计划。这有助于了解夹层动脉瘤发展过程中的各种现象。(c)2011爱思唯尔有限公司保留所有权利。
Aortic dissecting aneurysm is one of the most catastrophic cardiovascular emergencies that carries high mortality. It was pointed out from clinical observations that the aneurysm development is likely to be related to the hemodynamics condition of the dissected aorta. In order to gain more insight on the formation and progression of dissecting aneurysm, hemodynamic parameters including flow pattern, velocity distribution, aortic wall pressure and shear stress, which are difficult to measure in vivo, are evaluated using numerical simulations. Pulsatile blood flow in patient-specific dissecting aneurismal aortas before and after the formation of lumenal aneurysm (pre-aneurysm and post-aneurysm) is investigated by computational fluid dynamics (CFD) simulations. Realistic time-dependent boundary conditions are prescribed at various arteries of the complete aorta models. This study suggests the helical development of false lumen around true lumen may be related to the helical nature of hemodynamic flow in aorta. Narrowing of the aorta is responsible for the massive recirculation in the poststenosis region in the lumenal aneurysm development. High pressure difference of 0.21 kPa between true and false lumens in the pre-aneurismal aorta infers the possible lumenal aneurysm site in the descending aorta. It is also found that relatively high time-averaged wall shear stress (in the range of 4-8 kPa) may be associated with tear initiation and propagation. CFD modeling assists in medical planning by providing blood flow patterns, wall pressure and wall shear stress. This helps to understand various phenomena in the development of dissecting aneurysm. (c) 2011 Elsevier Ltd. All rights reserved.