Computational study of pulsatile blood flow in prototype vessel geometries of coronary segments.
Computational study of pulsatile blood flow in prototype vessel geometries of coronary segments.
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冠状动脉节段原型血管几何形状中脉动血流的计算研究。
DOI：
10.1016/j.ejmp.2009.03.004
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发表时间：
2010
影响因子：
3.4
通讯作者：
Marmarellis, V.
中科院分区：
文献类型：
--
作者：
Chaniotis, A. K.;Kaiktsis, L.;Katritsis, D.;Efstathopoulos, E.;Pantos, I.;Marmarellis, V.
通过数值模拟研究了冠状动脉节段原型血管几何结构中壁剪切应力（WSS）的时空分布，并讨论了其与血管疾病，特别是动脉粥样硬化和斑块破裂的潜在关联。特别给出了脉动、非牛顿血流条件下WSS时空分布的仿真结果：(a)不同曲率的弯曲管和(b)不同分支角度和流分的分叉管。在代表冠状动脉血流的雷诺数下，非牛顿流对WSS的影响（与牛顿流相比）较小。平均低WSS（和可能的动脉粥样硬化）的特定优先位点位于分叉后分支的外部区域，以及弯曲血管段的外入口和内出口流动区域。分叉血管部位的WSS下降更为显著（小于分叉前值的5%）。这些部位在空间和时间上也接近WSS变化的快速梯度，这一事实增加了斑块破裂的风险，可能在这些部位发生。在心脏周期收缩期开始和结束前后，WSS空间分布的时间变化非常快，同时也观察到血管内压力的强烈波动。这些快速而强烈的WSS和压力变化与心肌运动（心室收缩）引起的血管壁最大屈曲和机械应力在时间上是一致的。这些因素的结合可能会增加这些部位斑块破裂和血栓形成的风险。
The spatial and temporal distributions of wall shear stress (WSS) in prototype vessel geometries of coronary segments are investigated via numerical simulation, and the potential association with vascular disease and specifically atherosclerosis and plaque rupture is discussed. In particular, simulation results of WSS spatio-temporal distributions are presented for pulsatile, non-Newtonian blood flow conditions for: (a) curved pipes with different curvatures, and (b) bifurcating pipes with different branching angles and flow division. The effects of non-Newtonian flow on WSS (compared to Newtonian flow) are found to be small at Reynolds numbers representative of blood flow in coronary arteries. Specific preferential sites of average low WSS (and likely atherogenesis) were found at the outer regions of the bifurcating branches just after the bifurcation, and at the outer-entry and inner-exit flow regions of the curved vessel segment. The drop in WSS was more dramatic at the bifurcating vessel sites (less than 5% of the pre-bifurcation value). These sites were also near rapid gradients of WSS changes in space and time – a fact that increases the risk of rupture of plaque likely to develop at these sites. The time variation of the WSS spatial distributions was very rapid around the start and end of the systolic phase of the cardiac cycle, when strong fluctuations of intravascular pressure were also observed. These rapid and strong changes of WSS and pressure coincide temporally with the greatest flexion and mechanical stresses induced in the vessel wall by myocardial motion (ventricular contraction). The combination of these factors may increase the risk of plaque rupture and thrombus formation at these sites.
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影响因子：
10.8
作者：
BENSON, TJ;NEREM, RM;PEDLEY, TJ
通讯作者：
PEDLEY, TJ
DOI：
10.1016/s0368-1319(66)80056-x
发表时间：
1966-01-01
期刊：
JOURNAL OF ATHEROSCLEROSIS RESEARCH
影响因子：
--
作者：
CONSTANTINIDES, P
通讯作者：
CONSTANTINIDES, P
影响因子：
3.5
作者：
Doriot, PA
通讯作者：
Doriot, PA
影响因子：
20.1
作者：
ASAKURA, T;KARINO, T
通讯作者：
KARINO, T
影响因子：
5.3
作者：
FRIEDMAN, MH;BRINKMAN, AM;SEED, WA
通讯作者：
SEED, WA