A numerical study on the flow of blood and the transport of LDL in the human aorta: the physiological significance of the helical flow in the aortic arch
A numerical study on the flow of blood and the transport of LDL in the human aorta: the physiological significance of the helical flow in the aortic arch
复制标题
人体主动脉中血液流动和低密度脂蛋白转运的数值研究：主动脉弓螺旋流的生理意义
DOI：
10.1152/ajpheart.00266.2009
复制
发表时间：
2009-07-01
影响因子：
4.8
通讯作者：
Li, Shuyu
中科院分区：
文献类型：
--
作者：
Liu, Xiao;Pu, Fang;Li, Shuyu
刘X，蒲芳，范Y，邓X，李D，李S. A numerical study on the flow of blood and the transport of LDL in the human aortic：the physiological significance of the helical flow in the aortic arch. Am J Physiol Heart Circ Physiol 297：H163-H170，2009.首次发表于2009年5月8日; doi：10.1152/ajpheart.00266.2009。已经提出，称为低密度脂蛋白（LDL）的浓度极化的质量传递现象可能发生在动脉系统中，并且可能参与动脉粥样硬化形成的定位。为了验证这一假设，即LDL的浓度极化可能被抑制的螺旋流模式在人类主动脉，因此从动脉粥样硬化的主动脉，主动脉扭转，分支，曲率和锥度对血流和LDL运输的影响进行了数值模拟的影响下，稳态流动条件下，使用四个主动脉模型构建的基础上在体内MRI切片。结果表明，正是主动脉扭转引起主动脉弓内螺旋流动，稳定了主动脉内的血流，并补偿了主动脉弯曲对血流和LDL转运的不利影响。螺旋流降低了主动脉弓管腔表面LDL浓度，并可能在抑制弓上三个分支入口处LDL严重极化中发挥作用，从而保护它们免于动脉粥样硬化形成。主动脉的锥度是主动脉的另一个重要特征，它进一步稳定了血液的流动，并延迟了螺旋流的衰减，使其越过弓部并进入降主动脉的起始部分。因此，这些结果可以解释为什么升主动脉和主动脉弓相对没有动脉粥样硬化。
Liu X, Pu F, Fan Y, Deng X, Li D, Li S. A numerical study on the flow of blood and the transport of LDL in the human aorta: the physiological significance of the helical flow in the aortic arch. Am J Physiol Heart Circ Physiol 297: H163-H170, 2009. First published May 8, 2009; doi:10.1152/ajpheart.00266.2009.-It has been proposed that a mass transfer phenomenon called concentration polarization of low-density lipoproteins (LDLs) may occur in the arterial system and is likely involved in the localization of atherogenesis. To test the hypothesis that concentration polarization of LDL may be suppressed by the helical flow pattern in the human aorta, hence sparing the ascending aorta from atherosclerosis, the effects of aortic torsion, branching, curvature, and taper on blood flow and LDL transport in the lumen were simulated numerically under steady-state flow conditions using four aorta models constructed based on in vivo MRI slices. The results showed that it was the aortic torsion that induced the helical flow in the aortic arch, stabilizing the flow of blood in the aorta, and compensated the adverse effects of the aortic curvature on blood flow and LDL transport. The helical flow reduced the luminal surface LDL concentration in the aortic arch and probably played a role in suppressing severe polarization of LDL at the entrances of the three branches on the arch, hence, protecting them from atherogenesis. The taper of the aorta was another important feature of the aorta that further stabilized the flow of blood and delayed the attenuation of the helical flow, making it move beyond the arch and into the beginning part of the descending aorta. The results therefore may account for why the ascending aorta and the arch are relatively free of atherosclerosis.