[A boundary element analysis on hemodynamic characteristics at the bifurcation of abdominal arterial]

The hemodynamic characteristics of abdominal arterial bifurcation, such as blood flowing velocity vector, the shear stress at the vessel wall were calculated, studied and compared using the newly-induced boundary element method in this study. It was analysed why the atherosclerosis is asymmetrical at the bifurcation of abdominal arterial. The hemodynamic causes of production and development of the atherosclerotic were reasonabley explained by the shear stress calculation results of left and right common iliac branch vessel walls before and after the lesions. It is shown that the distribution of blood flowing velocity vector, the shear stress at the vessel wall are asymmetrical because of the asymmetrical geometry at the bifurcation of abdominal arterial, so that the shear stress of inner wall is higher than outside. The inner wall shear stress of right common iliac is higher than left. Blood velocity and shear stress increase at the atherosclerotic lesion because the blood vessel becomes narrower, and the blood velocity and shear stress decrease at the downstream of the lesion. It was also shown that the hemodynamic characteristics played a great important role in the occurrence and development of the atherosclerosis diseases at the bifurcation of abdominal arterial. Because of the increase of the shear stress, the atherosclerotic plaque surface will be damaged, leading to tissue hyperplasia. It will be lead to blood cell coacervation that the blood velocity and shear stress decrease at the atherosclerotic plaque downstream.