PULSATILE VELOCITY-MEASUREMENTS IN A MODEL OF THE HUMAN ABDOMINAL-AORTA UNDER SIMULATED EXERCISE AND POSTPRANDIAL CONDITIONS
PULSATILE VELOCITY-MEASUREMENTS IN A MODEL OF THE HUMAN ABDOMINAL-AORTA UNDER SIMULATED EXERCISE AND POSTPRANDIAL CONDITIONS
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DOI：
10.1115/1.2895692
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发表时间：
1994-02-01
影响因子：
1.7
通讯作者：
KU, DN
中科院分区：
文献类型：
--
作者：
MOORE, JE;KU, DN
本研究考察了在运动和餐后条件下发生的血流速率和脉搏率生理变化时腹主动脉的血流动力学。使用体外模型进行血流动力学测量，该模型考虑了腹主动脉的七个主要分支，曲率和脉冲性。采用相速度编码的磁共振成像测速技术，测量了三个轴向位置全断面的脉动轴向速度剖面。在模拟运动条件下，前向速度大约是休息时的两倍，并且休息条件下的流量反转大大减少。在肾下主动脉后壁附近，只有21%的心率为负，而在静息状态下为82%。餐后条件下的峰值流速降低了25%，靠近肠系膜上动脉远端的主动脉左前壁附近的平均流速降低了33%（与静息条件相比）。不同生理条件下腹主动脉血流动力学的变化可能影响该部位动脉粥样硬化的进展速度。
This study examines the hemodynamics of the abdominal aorta during physiological changes in flow rates and pulse rate that occur under exercise and postprandial conditions. Hemodynamic measurements were performed using an in vitro model which took into account seven major branches, the curvature, and the pulsatile nature of brood flow of the abdominal aorta. Magnetic Resonance Imaging velocimetry employing phase-velocity encoding was used to measure the pulsatile axial velocity profiles for the entire cross-section at three axial locations. Under simulated exercise conditions, the forward velocities were approximately double those seen during rest, and the flow reversal seen for resting conditions was greatly reduced. Near the posterior wall of the infrarenal aorta, the velocities were negative for only 21 percent of the cardiac cycle as compared with 82 percent for resting conditions. Postprandial conditions produced a 25 percent reduction in peak velocity and a 33 percent reduction in mean velocity near the left anterior wall of the aorta just distal to the superior mesenteric artery (in comparison with resting conditions). The changes that can occur in abdominal aorta hemodynamics under different physiologic conditions may affect the rate of progression of atherosclerosis at this site.