Effects of Geometric Variations on the Buckling of Arteries.
Effects of Geometric Variations on the Buckling of Arteries.
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DOI：
10.1142/s1758825111001044
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发表时间：
2011-10-05
影响因子：
3.5
通讯作者：
Han HC
中科院分区：
文献类型：
--
作者：
Datir P;Lee AY;Lamm SD;Han HC
动脉通常表现出几何变化，例如椭圆形和偏心横截面、狭窄和沿纵轴沿着逐渐变细。尚未研究这些变化对动脉壁机械稳定性的影响。本研究的目的是确定具有椭圆形、偏心、狭窄和锥形横截面的动脉的屈曲行为。动脉壁被建模为均匀的各向异性非线性材料。采用有限元分析方法模拟了这些动脉在管腔压力和轴向拉伸下的屈曲过程。我们的研究结果表明，与圆形动脉相比，具有椭圆形横截面的动脉在较低的临界压力下在短轴方向上屈曲。偏心横截面、狭窄和锥形也降低了临界压力。狭窄导致沿血管沿着的巨大压力变化，并降低了屈曲压力。此外，逐渐变细使动脉的屈曲变形轮廓向远端移动。我们的结论是，几何形状的变化降低了动脉的临界压力，从而使动脉更容易机械不稳定比圆柱形动脉。这些结果提高了我们对动脉力学行为的理解。
Arteries often demonstrate geometric variations such as elliptic and eccentric cross sections, stenosis, and tapering along the longitudinal axis. Effects of these variations on the mechanical stability of the arterial wall have not been investigated. The objective of this study was to determine the buckling behavior of arteries with elliptic, eccentric, stenotic, and tapered cross sections. The arterial wall was modeled as a homogenous anisotropic nonlinear material. Finite element analysis was used to simulate the buckling process of these arteries under lumen pressure and axial stretch. Our results demonstrated that arteries with an oval cross section buckled in the short axis direction at lower critical pressures compared to circular arteries. Eccentric cross-sections, stenosis, and tapering also decreased the critical pressure. Stenosis led to dramatic pressure variations along the vessel and reduced the buckling pressure. In addition, tapering shifted the buckling deformation profile of the artery towards the distal end. We conclude that geometric variations reduce the critical pressure of arteries and thus make the arteries more prone to mechanical instability than circular cylindrical arteries. These results improve our understanding of the mechanical behavior of arteries.