Chandran K B
Department of Biomedical Engineering, University of Iowa, Iowa City 52242-1527.
J Biomech Eng. 1993 Nov;115(4B):611-6. doi: 10.1115/1.2895548.
The aorta is the major blood vessel transporting blood pumped by the left ventricle to the systemic circulation. The tricuspid aortic value at the root of the aorta provides a centralized flow with nearly uniform velocity profile into the ascending aorta. The aorta consisting of the ascending limb, the aortic arch, and the descending segment is a vessel of complex geometry including curvature in multiple planes, branches and bifurcation as well as taper. The understanding of the development of blood flow in this distensible vessel has been the subject of several theoretical as well as experimental investigations. Flow development in the aorta and in the branch vessels has been of interest in delineating the role of wall shear stresses on the etiology of atherosclerosis. In this paper, a review of the current status on our understanding of the complex flow dynamics in the aorta is presented. With the advent of transesophageal echocardiography and magnetic resonance velocity mapping, further evidence of the presence of secondary flows even in the descending aorta has been reported. The importance of the effect of secondary flow in the descending aorta on the perfusion of distal blood vessels (such as superior mesenteric and renal arterial branches) as well as in the iliac bifurcation is also included in the discussion.
主动脉是将左心室泵出的血液输送到体循环的主要血管。主动脉根部的三尖瓣主动脉瓣使血液集中流动，以近乎均匀的速度分布进入升主动脉。主动脉由升支、主动脉弓和降段组成，是一种几何形状复杂的血管，包括多个平面的弯曲、分支和分叉以及逐渐变细。对这种可扩张血管中血流发展的理解一直是多项理论和实验研究的主题。主动脉和分支血管中的血流发展对于阐明壁面剪应力在动脉粥样硬化病因学中的作用具有重要意义。本文对我们目前对主动脉复杂流动动力学的理解现状进行了综述。随着经食管超声心动图和磁共振速度成像技术的出现，有报道称即使在降主动脉中也存在二次流的进一步证据。降主动脉中二次流对远端血管（如肠系膜上动脉和肾动脉分支）灌注以及髂动脉分叉处灌注的影响的重要性也在讨论中。
