title: Creating a model of diseased artery damage and failure from healthy porcine aorta.
abstract: Large quantities of diseased tissue are required in the research and development of new generations of medical devices, for example for use in physical testing. However, these are difficult to obtain. In contrast, porcine arteries are readily available as they are regarded as waste. Therefore, reliable means of creating from porcine tissue physical models of diseased human tissue that emulate well the associated mechanical changes would be valuable. To this end, we studied the effect on mechanical response of treating porcine thoracic aorta with collagenase, elastase and glutaraldehyde. The alterations in mechanical and failure properties were assessed via uniaxial tension testing. A constitutive model composed of the Gasser-Ogden-Holzapfel model, for elastic response, and a continuum damage model, for the failure, was also employed to provide a further basis for comparison (Calvo and Peña, 2006; Gasser et al., 2006). For the concentrations used here it was found that: collagenase treated samples showed decreased fracture stress in the axial direction only; elastase treated samples showed increased fracture stress in the circumferential direction only; and glutaraldehyde samples showed no change in either direction. With respect to the proposed constitutive model, both collagenase and elastase had a strong effect on the fibre-related terms. The model more closely captured the tissue response in the circumferential direction, due to the smoother and sharper transition from damage initiation to complete failure in this direction. Finally, comparison of the results with those of tensile tests on diseased tissues suggests that these treatments indeed provide a basis for creation of physical models of diseased arteries.
authors.affiliation: CISTIB, Centre for Computational Imaging and Simulation Technologies in Biomedicine, INSIGNEO Institute for in silico Medicine, Department of Mechanical Engineering, The University of Sheffield, Sheffield, UK. Electronic address: mta08cn@sheffield.ac.uk.
authors.forename: Christopher
authors.initials: C
authors.lastname: Noble
authors.affiliation: Philips Research, Eindhoven, The Netherlands.
authors.forename: Nicole
authors.initials: N
authors.lastname: Smulders
authors.affiliation: Department of Materials Science and Engineering, The Kroto Research Institute, North Campus, University of Sheffield, Broad Lane, Sheffield, UK.
authors.forename: Nicola H
authors.initials: NH
authors.lastname: Green
authors.affiliation: Department of Mechanical Engineering, The University of Sheffield, Sheffield, UK.
authors.forename: Roger
authors.initials: R
authors.lastname: Lewis
authors.affiliation: Department of Mechanical Engineering, The University of Sheffield, Sheffield, UK.
authors.forename: Matt J
authors.initials: MJ
authors.lastname: Carré
authors.affiliation: Philips Research, Eindhoven, The Netherlands.
authors.forename: Steve E
authors.initials: SE
authors.lastname: Franklin
authors.affiliation: Department of Materials Science and Engineering, The Kroto Research Institute, North Campus, University of Sheffield, Broad Lane, Sheffield, UK.
authors.forename: Sheila
authors.initials: S
authors.lastname: MacNeil
authors.affiliation: CISTIB, Centre for Computational Imaging and Simulation Technologies in Biomedicine, INSIGNEO Institute for in silico Medicine, Department of Mechanical Engineering, The University of Sheffield, Sheffield, UK.
authors.forename: Zeike A
authors.initials: ZA
authors.lastname: Taylor
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic / Q000473:pathology*; D001696:Biomechanical Phenomena; D017364:Collagenases; D004195:Disease Models, Animal; D005976:Glutaral; D006331:Heart Diseases / Q000473:pathology*; D006801:Humans; D010196:Pancreatic Elastase; D013314:Stress, Mechanical; D013552:Swine
chemical_list: D010196:Pancreatic Elastase; D017364:Collagenases; D005976:Glutaral
keywords: Collagenase; Diseased tissue model; Elastase; Glutaraldehyde; Porcine aorta; Uniaxial tension