145076 20260217205555.0 doi 10.1016/j.actbio.2024.08.028 sideral 139878 ART-2024-139878 eng Laita, Nicolás Universidad de Zaragoza (orcid)0000-0001-8946-4829 A comprehensive experimental analysis of the local passive response across the healthy porcine left ventricle 2024 Access copy available to the general public Unrestricted This work provides a comprehensive characterization of porcine myocardial tissue, combining true biaxial (TBx), simple triaxial shear (STS) and confined compression (CC) tests to analyze its elastic behavior under cyclic loads. We expanded this study to different zones of the ventricular free wall, providing insights into the local behavior along the longitudinal and radial coordinates. The aging impact was also assessed by comparing two age groups (4 and 8 months). Resulting data showed that the myocardium exhibits a highly nonlinear hyperelastic and incompressible behavior. We observed an anisotropy ratio of 2-2.4 between averaged peak stresses in TBx tests and 1-0.59-0.40 orthotropy ratios for normalised fiber-sheet-normal peak stresses in STS tests. We obtained a highly incompressible response, reaching volumetric pressures of 2-7 MPa for perfused tissue in CC tests, with notable differences when fluid drainage was allowed, suggesting a high permeability. Regional analysis showed reduced stiffness and anisotropy (20-25%) at the apical region compared to the medial, which we attributed to differences in the fiber field dispersion. Compressibility also increased towards the epicardium and apical regions. Regarding age-related variations, 8-month animals showed stiffer response (at least 25% increase), particularly in directions where the mechanical stress is absorbed by collagenous fibers (more than 90%), as supported by a histological analysis. Although compressibility of perfused tissue remained unchanged, permeability significantly reduced in 8-month-old animals. Our findings offer new insights into myocardial properties, emphasizing on local variations, which can help to get a more realistic understanding of cardiac mechanics in this common animal model. Statement of significance: In this work, we conducted a comprehensive analysis of the passive mechanical behavior of porcine myocardial tissue through biaxial, triaxial shear, and confined compression tests. Unlike previous research, we investigated the variation in mechanical response across the left ventricular free wall, conventionally assumed homogeneous, revealing differences in terms of stiffness and compressibility. Additionally, we evaluated age-related effects on mechanical properties by comparing two age groups, observing significant variations in stiffness and permeability. To date, there has been no such in-depth exploration of myocardial elastic response and compressibility considering regional variations along the wall and may contribute to a better understanding of the cardiac tissue’s passive mechanical response. nfo:eu-repo/grantAgreement/ES/AEI/PID2022-140219OB-I00 info:eu-repo/grantAgreement/EC/H2020/874827/EU/Computational biomechanics and bioengineering 3D printing to develop a personalized regenerative biological ventricular assist device to provide lasting functional support to damaged hearts/BRAV3 This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No H2020 874827-BRAV3 info:eu-repo/grantAgreement/ES/MCIN/PLEC2021-008127 info:eu-repo/grantAgreement/ES/UZ/ICTS NANBIOSIS-U13 Unit-CIBER-BBN info:eu-repo/semantics/openAccess by-nc-nd https://creativecommons.org/licenses/by-nc-nd/4.0/deed.es 9.6 2024 MATERIALS SCIENCE, BIOMATERIALS 7 / 55 = 0.127 2024 Q1 T1 ENGINEERING, BIOMEDICAL 11 / 124 = 0.089 2024 Q1 T1 2.007 2024 Biochemistry 2024 Q1 Biomaterials 2024 Q1 Molecular Biology 2024 Q1 Biotechnology 2024 Q1 Medicine (miscellaneous) 2024 Q1 Biomedical Engineering 2024 Q1 17.8 2024 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Aparici-Gil, Alejandro Oliván-Viguera, Aida (orcid)0000-0001-5348-924X Pérez-Martínez, Alba Universidad de Zaragoza Martínez, Miguel Ángel Universidad de Zaragoza (orcid)0000-0002-8375-0354 Doblaré, Manuel Universidad de Zaragoza (orcid)0000-0001-8741-6452 Peña, Estefanía Universidad de Zaragoza (orcid)0000-0002-0664-5024 5008 800 Universidad de Zaragoza Dpto. Ingeniería Electrón.Com. Área Teoría Señal y Comunicac. 5004 605 Universidad de Zaragoza Dpto. Ingeniería Mecánica Área Mec.Med.Cont. y Teor.Est. 187 (2024), 261-277 Acta Biomater. ACTA BIOMATERIALIA 1742-7061 3457805 http://zaguan.unizar.es/record/145076/files/texto_completo.pdf Versión publicada 2419780 http://zaguan.unizar.es/record/145076/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:145076 articulos driver 2026-02-17-20:42:20 ARTICLE