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

• Published in: Computers in biology and medicine Vol. 166; p. 107561
• Main Authors: Guo, Xiaoya, Gong, Chanjuan, Zhai, Yali, Yu, Han, Li, Jiantao, Sun, Haoliang, Wang, Liang, Tang, Dalin
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.11.2023; Elsevier Limited
• Subjects: Adult; Aged; Anisotropy; Aorta; Aorta - diagnostic imaging; Aorta - physiopathology; Aortic Aneurysm - diagnostic imaging; Aortic Aneurysm - physiopathology; Aortic dissection; Aortic Dissection - diagnostic imaging; Aortic Dissection - physiopathology; Arteriosclerosis; Atherosclerosis; Atherosclerosis - diagnostic imaging; Atherosclerosis - physiopathology; Axial stress; Biaxial tensile testing; Biaxial tests; Biomechanical Phenomena - physiology; Biomechanical stress/strain; Biomechanics; Blood pressure; Calcification; Computed tomography; Coronary vessels; Cryopreservation; Decision making; Dissection; Echocardiography; Female; Finite Element Analysis; Finite element method; Hospitals; Humans; Internal Medicine; Male; Material properties; Mathematical models; Mechanical properties; Medical imaging; Middle Aged; Models, Cardiovascular; Morphology; Mortality; Other; Parameters; Patient-specific model; Patients; Physiology; Statistical analysis; Strain; Stress analysis; Stress, Mechanical; Tensile tests; Jiangsu China; China; Aortic dissection; Patient-specific model; Biaxial tensile testing; Biomechanical stress/strain; Atherosclerosis; Material properties
• ISSN: 0010-4825; 1879-0534; 1879-0534
• DOI: 10.1016/j.compbiomed.2023.107561

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. 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. Material parameters of anisotropic Mooney-Rivlin model were fitted with average R2 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). 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. •Biomechanical factors could potentially distinguish different aortic pathologies.•Aortic biomechanics should be considered for aortic dissection prediction.•Biomechanical modeling provides an approach to study aortic diseases development.