Graz University of Technology, Institute of Biomechanics, Kronesgasse 5-I, 8010 Graz, Austria.
Centre for Applied Biomedical Engineering Research, Department of Mechanical, Aeronautical and Biomedical Engineering and the Materials and Surface Science Institute, University of Limerick, Ireland.
J Biomech. 2014 Mar 3;47(4):859-69. doi: 10.1016/j.jbiomech.2014.01.011. Epub 2014 Jan 21.
Vulnerable and stable atherosclerotic plaques are heterogeneous living materials with peculiar mechanical behaviors depending on geometry, composition, loading and boundary conditions. Computational approaches have the potential to characterize the three-dimensional stress/strain distributions in patient-specific diseased arteries of different types and sclerotic morphologies and to estimate the risk of plaque rupture which is the main trigger of acute cardiovascular events. This review article attempts to summarize a few finite element (FE) studies for different vessel types, and how these studies were performed focusing on the used stress measure, inclusion of residual stress, used imaging modality and material model. In addition to histology the most used imaging modalities are described, the most common nonlinear material models and the limited number of models for plaque rupture used for such studies are provided in more detail. A critical discussion on stress measures and threshold stress values for plaque rupture used within the FE studies emphasizes the need to develop a more location and tissue-specific threshold value, and a more appropriate failure criterion. With this addition future FE studies should also consider more advanced strain-energy functions which then fit better to location and tissue-specific experimental data.
易损和稳定的动脉粥样硬化斑块是具有特殊力学行为的异质活体材料,其力学行为取决于几何形状、组成、载荷和边界条件。计算方法有可能对不同类型和硬化形态的患者特定病变动脉中的三维应力/应变分布进行特征化,并估计斑块破裂的风险,斑块破裂是急性心血管事件的主要触发因素。本文综述了少数针对不同血管类型的有限元(FE)研究,以及这些研究如何重点关注所使用的应力测量、残余应力的包含、所使用的成像方式和材料模型。除了组织学,还描述了最常用的成像方式,提供了用于此类研究的最常见的非线性材料模型和斑块破裂的有限数量的模型。对 FE 研究中使用的斑块破裂的应力测量和阈值应力值进行了批判性讨论,强调需要开发更具位置和组织特异性的阈值值和更合适的失效准则。通过这种改进,未来的 FE 研究还应该考虑更先进的应变能函数,这些函数更适合位置和组织特异性的实验数据。