经双向测试实验、本构模型和有限元分析对正常和病态人体升主动脉组织的生物力学特性进行研究。

Biomechanical characterization of normal and pathological human ascending aortic tissues via biaxial testing Experiment, constitutive modeling and finite element analysis.

机构信息

College of Science, Nanjing University of Posts and Telecommunications, Nanjing, 210023, China.

Department of Anesthesiology, First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China.

出版信息

Comput Biol Med. 2023 Nov;166:107561. doi: 10.1016/j.compbiomed.2023.107561. Epub 2023 Oct 11.

DOI:10.1016/j.compbiomed.2023.107561

PMID:37857134

Abstract

BACKGROUND

Aortic dissection and atherosclerosis are two common pathological conditions affecting the aorta. Aortic biomechanics are believed to be closely associated with the pathological development of these diseases. However, the biomechanical environment that predisposes the aortic wall to these pathological conditions remains unclear.

METHODS

Sixteen ascending aortic specimens were harvested from 16 human subjects and further categorized into three groups according to their disease states: aortic dissection group, aortic dissection with accompanied atherosclerosis group and healthy group. Experimental stress-strain data from biaxial tensile testing were used to fit the anisotropic Mooney-Rivlin model to determine material parameters. Computed tomography images or transesophageal echocardiography images were collected to construct computational models to simulate the stress/strain distributions in aortas at the pre-dissection state. Statistical analyses were performed to identify the biomechanical factors to distinguish three groups of aortic tissues.

RESULTS

Material parameters of anisotropic Mooney-Rivlin model were fitted with average R value 0.9749. The aortic diameter showed no significant difference among three groups. Changes of maximum and average stress values from minimum pressure to maximum pressure (△MaxStress and △AveStress) had significantly difference between dissection group and dissection with accompanied atherosclerosis group (p = 0.0201 and 0.0102). Changes of maximum and average strain values from minimum pressure to maximum pressure (△MaxStrain and △AveStrain) from dissection group were significant different from healthy group (p = 0.0171 and 0.0281).

CONCLUSION

Changes of stress and strain values during the cardiac cycle are good biomechanical factors for predicting potential aortic dissection and aortic dissection accompanied with atherosclerosis.

摘要

背景

主动脉夹层和动脉粥样硬化是两种常见的影响主动脉的病理状况。主动脉生物力学与这些疾病的病理发展密切相关。然而，导致主动脉壁易患这些病理状况的生物力学环境尚不清楚。

方法

从 16 名人类受试者中采集了 16 个升主动脉标本，并根据其疾病状态进一步分为三组：主动脉夹层组、主动脉夹层伴动脉粥样硬化组和健康组。使用双轴拉伸试验的实验应力-应变数据拟合各向异性的 Mooney-Rivlin 模型，以确定材料参数。采集计算机断层扫描图像或经食管超声心动图图像，构建计算模型，模拟夹层前主动脉的应力/应变分布。进行统计分析，以确定区分三组主动脉组织的生物力学因素。

结果

各向异性的 Mooney-Rivlin 模型的材料参数拟合平均 R 值为 0.9749。三组之间的主动脉直径没有显著差异。从最小压力到最大压力的最大和平均应力值的变化（△MaxStress 和△AveStress）在夹层组和夹层伴动脉粥样硬化组之间有显著差异（p=0.0201 和 0.0102）。从最小压力到最大压力的最大和平均应变值的变化（△MaxStrain 和△AveStrain）在夹层组与健康组之间有显著差异（p=0.0171 和 0.0281）。