title: Atherosclerotic plaque delamination: Experiments and 2D finite element model to simulate plaque peeling in two strains of transgenic mice.
abstract: Finite element analyses using cohesive zone models (CZM) can be used to predict the fracture of atherosclerotic plaques but this requires setting appropriate values of the model parameters. In this study, material parameters of a CZM were identified for the first time on two groups of mice (ApoE-/-and ApoE-/-Col8-/-) using the measured force-displacement curves acquired during delamination tests. To this end, a 2D finite-element model of each plaque was solved using an explicit integration scheme. Each constituent of the plaque was modeled with a neo-Hookean strain energy density function and a CZM was used for the interface. The model parameters were calibrated by minimizing the quadratic deviation between the experimental force displacement curves and the model predictions. The elastic parameter of the plaque and the CZM interfacial parameter were successfully identified for a cohort of 11 mice. The results revealed that only the elastic parameter was significantly different between the two groups, ApoE-/-Col8-/-plaques being less stiff than ApoE-/-plaques. Finally, this study demonstrated that a simple 2D finite element model with cohesive elements can reproduce fairly well the plaque peeling global response. Future work will focus on understanding the main biological determinants of regional and inter-individual variations of the material parameters used in the model.
authors.affiliation: SaInBioSE, INSERM, U1059 Mines Saint-Etienne, F-42023 Saint Etienne, France; Department of Biomedical Engineering, University of South Carolina, Columbia, SC 29208, USA. Electronic address: merei@emse.fr.
authors.forename: Bilal
authors.initials: B
authors.lastname: Merei
authors.affiliation: SaInBioSE, INSERM, U1059 Mines Saint-Etienne, F-42023 Saint Etienne, France. Electronic address: badel@emse.fr.
authors.forename: Pierre
authors.initials: P
authors.lastname: Badel
authors.affiliation: Department of Biomedical Engineering, University of South Carolina, Columbia, SC 29208, USA. Electronic address: davis79@email.sc.edu.
authors.forename: Lindsey
authors.initials: L
authors.lastname: Davis
authors.affiliation: Department of Mechanical Engineering, University of South Carolina, Columbia, SC 29208, USA. Electronic address: sutton@cec.sc.edu.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Sutton
authors.affiliation: SaInBioSE, INSERM, U1059 Mines Saint-Etienne, F-42023 Saint Etienne, France. Electronic address: avril@emse.fr.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Avril
authors.affiliation: Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC 29208, USA. Electronic address: lessner@uscmed.sc.edu.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Lessner
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D020342:Finite Element Analysis; D051379:Mice; D000074085:Mice, Knockout, ApoE; D008822:Mice, Transgenic; D058226:Plaque, Atherosclerotic / Q000473:pathology*
keywords: Cohesive zone model; Collagen VIII; Explicit scheme; Inverse approach; Parameter identification; Plaque delamination