title: A discrete mesoscopic particle model of the mechanics of a multi-constituent arterial wall.
abstract: Blood vessels have unique properties that allow them to function together within a complex, self-regulating network. The contractile capacity of the wall combined with complex mechanical properties of the extracellular matrix enables vessels to adapt to changes in haemodynamic loading. Homogenized phenomenological and multi-constituent, structurally motivated continuum models have successfully captured these mechanical properties, but truly describing intricate microstructural details of the arterial wall may require a discrete framework. Such an approach would facilitate modelling interactions between or the separation of layers of the wall and would offer the advantage of seamless integration with discrete models of complex blood flow. We present a discrete particle model of a multi-constituent, nonlinearly elastic, anisotropic arterial wall, which we develop using the dissipative particle dynamics method. Mimicking basic features of the microstructure of the arterial wall, the model comprises an elastin matrix having isotropic nonlinear elastic properties plus anisotropic fibre reinforcement that represents the stiffer collagen fibres of the wall. These collagen fibres are distributed evenly and are oriented in four directions, symmetric to the vessel axis. Experimental results from biaxial mechanical tests of an artery are used for model validation, and a delamination test is simulated to demonstrate the new capabilities of the model.
authors.affiliation: Division of Applied Mathematics, Brown University, Providence, RI 02912, USA.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Witthoft
authors.affiliation: Division of Applied Mathematics, Brown University, Providence, RI 02912, USA.
authors.forename: Alireza
authors.initials: A
authors.lastname: Yazdani
authors.affiliation: Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, IN 46556, USA.
authors.forename: Zhangli
authors.initials: Z
authors.lastname: Peng
authors.affiliation: Department of Biomedical Engineering, Yale University, New Haven, CT 06520, USA.
authors.forename: Chiara
authors.initials: C
authors.lastname: Bellini
authors.affiliation: Department of Biomedical Engineering, Yale University, New Haven, CT 06520, USA.
authors.forename: Jay D
authors.initials: JD
authors.lastname: Humphrey
authors.affiliation: Division of Applied Mathematics, Brown University, Providence, RI 02912, USA george_karniadakis@brown.edu.
authors.forename: George Em
authors.initials: GE
authors.lastname: Karniadakis
mesh_terms: D000818:Animals; D001158:Arteries / Q000033:anatomy & histology / Q000502:physiology*; D001783:Blood Flow Velocity / Q000502:physiology; D004548:Elasticity / Q000502:physiology*; D006801:Humans; D008955:Models, Cardiovascular
keywords: artery microstructure; dissection; dissipative particle dynamics; nonlinear elasticity