Zheng Xianbing, Ren Jiusheng
Shanghai Institute of Applied Mathematics and Mechanics, Shanghai 200072, China.
Shanghai Key Laboratory of Mechanics in Energy Engineering, Department of Mechanics, Shanghai University, Shanghai 200444, China.
J Theor Biol. 2016 Mar 21;393:118-26. doi: 10.1016/j.jtbi.2015.12.015. Epub 2016 Jan 15.
Effects of the three-dimensional residual stresses on the mechanical properties of arterial walls are analyzed in this paper, based on the model which considered the bending and stretching both in the circumferential and axial directions of the three distinct arterial layers. Moreover, different constitutive models are proposed to quantify the nonlinear mechanics of the three distinct layers and the important constituents, i.e. elastin, collagen fibers and smooth muscle cells (SMCs), are all taken into account. The stress distributions and pressure-radius curves of the arterial wall are given in details. Results demonstrate that the maximum values of the circumferential stress and the corresponding stress gradient in the media under the mean arterial pressure are reduced significantly as a consequence of the SMCs. The bending in the axial direction of the media and the opening angle of the intima have an obvious impact on the mechanical behaviors of arterial walls. This study may not only develop the understanding of effects of the three-dimensional residual stresses on the arterial wall response, but also can increase the accuracy of the analyses for patient-specific studies used for the treatments of arterial diseases.
本文基于一个考虑了三个不同动脉层在圆周和轴向方向上的弯曲和拉伸的模型，分析了三维残余应力对动脉壁力学性能的影响。此外，还提出了不同的本构模型来量化三个不同层的非线性力学，并考虑了重要成分，即弹性蛋白、胶原纤维和平滑肌细胞（SMC）。详细给出了动脉壁的应力分布和压力-半径曲线。结果表明，由于平滑肌细胞的存在，平均动脉压下中膜圆周应力的最大值及其相应的应力梯度显著降低。中膜轴向的弯曲和内膜的开口角度对动脉壁的力学行为有明显影响。本研究不仅可以加深对三维残余应力对动脉壁响应影响的理解，还可以提高用于动脉疾病治疗的患者特异性研究分析的准确性。
