Institute of Biomechanics, Graz University of Technology, Graz, Austria.
GRANTE-Department of Mechanical Engineering, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil.
J R Soc Interface. 2023 Nov;20(208):20230472. doi: 10.1098/rsif.2023.0472. Epub 2023 Nov 1.
Abdominal aortic aneurysms (AAAs) are a serious condition whose pathophysiology is related to phenomena occurring at different length scales. To gain a better understanding of the disease, this work presents a multi-scale computational study that correlates AAA progression with microstructural and mechanical alterations in the tissue. Macro-scale geometries of a healthy aorta and idealized aneurysms with increasing diameter are developed on the basis of existing experimental data and subjected to physiological boundary conditions. Subsequently, microscopic representative volume elements of the abluminal side of each macro-model are employed to analyse the local kinematics at the cellular scale. The results suggest that the formation of the aneurysm disrupts the micromechanics of healthy tissue, which could trigger collagen growth and remodelling by mechanosensing cells. The resulting changes to the macro-mechanics and microstructure of the tissue seem to establish a new homeostatic state at the cellular scale, at least for the diameter range investigated.
腹主动脉瘤(AAA)是一种严重的疾病,其病理生理学与不同长度尺度上发生的现象有关。为了更好地了解这种疾病,本工作进行了一项多尺度计算研究,将 AAA 的进展与组织的微观结构和力学变化相关联。在现有实验数据的基础上,基于现有实验数据,为健康主动脉和直径不断增大的理想化动脉瘤开发了宏观尺度的几何形状,并对其施加生理边界条件。随后,使用每个宏观模型的外膜侧的微观代表性体积元素来分析细胞尺度上的局部运动学。结果表明,动脉瘤的形成破坏了健康组织的微力学,这可能通过机械敏感细胞触发胶原蛋白的生长和重塑。组织的宏观力学和微观结构的这些变化似乎在细胞尺度上建立了一种新的平衡状态,至少在研究的直径范围内是这样。