Affiliations: Aragón Institute of Engineering Research (I3A), University of Zaragoza, Zaragoza, Spain | CIBER de Bioingeniereía, Biomateriales y Nanomedicina, Zaragoza, Spain
Note: [] Address for correspondence: Prof. Estefanía Peña, Aragón Institute of Engineering Research, Mechanical Engineering Department, University of Zaragoza, María de Luna, 3 E-50018, Zaragoza, Spain. Tel.: +34 876 55 52 33; Fax: +34 976 76 25 78; E-mail: fany@unizar.es.
Abstract: The viscoelastic properties of porcine carotid tissue are investigated in this work. Experimental uniaxial stress relaxation tests along the longitudinal and circumferential directions of the vessel were performed for carotid strips extracted from 10 vessels. Directional and local differences – distal versus proximal position – in the tissue behavior were investigated. The experimental tests reveal a highly anisotropic, non-linear viscoelastic response and local dependence of the samples. The carotid artery shows anisotropic relaxation behavior for both proximal and distal samples. The highest stress relaxation was found in the circumferential tensile test for the highest applied strain at the distal position. For the circumferential direction, the relaxation stress was higher than in the longitudinal being at its highest in the distal position. These facts show that the stress relaxation is higher in the distal than in the proximal position. However, there are no differences between both positions in the longitudinal direction. In addition, a constitutive law that takes into account the fundamental features, including non-linear viscoelasticity, of the arterial tissue is proposed. The present results are correlated with the purely elastic response and the microstructural analysis of the tissue by means of histological quantification presented in a previous study.
Keywords: Viscoelasticity, constitutive model, muscular and elastic artery
DOI: 10.3233/BIR-2012-0606
Journal: Biorheology, vol. 49, no. 4, pp. 271-288, 2012
