title: Characterization of arterial wall mechanical behavior and stresses from human clinical data.
abstract: This paper demonstrates the feasibility of material identification and wall stress computation for human common carotid arteries based on non-invasive in vivo clinical data: dynamical intraluminal pressure measured by applanation tonometry, and medial diameter and intimal-medial thickness measured by high-resolution ultrasound echotracking. The mechanical behavior was quantified assuming an axially pre-stretched, thick-walled, cylindrical artery subjected to dynamical blood pressure and perivascular constraints. The wall was further assumed to be three-dimensional and to consist of a nonlinear, hyperelastic, anisotropic, incompressible material with smooth muscle activity and residual stresses. Mechanical contributions by individual constituents--an elastin-dominated matrix, collagen fibers, and vascular smooth muscle--were accounted for using a previously proposed microstructurally motivated constitutive relation. The in vivo boundary value problem was solved semi-analytically to compute the inner pressure during a mean cardiac cycle. Using a nonlinear least-squares method, optimal model parameters were determined by minimizing differences between computed and measured inner pressures over a mean cardiac cycle. The fit-to-data from two healthy patients was very good and the predicted radial, circumferential, and axial stretch and stress fields were sensible. Hence, the proposed approach was able to identify complex geometric and material parameters directly from non-invasive in vivo human data.
authors.affiliation: CNRS UMR 7054, Faculté de Médecine, Université Paris 12, 8 Rue du Général Sarrail, Créteil F-94010, France.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Masson
authors.forename: Pierre
authors.initials: P
authors.lastname: Boutouyrie
authors.forename: Stéphane
authors.initials: S
authors.lastname: Laurent
authors.forename: Jay D
authors.initials: JD
authors.lastname: Humphrey
authors.forename: Mustapha
authors.initials: M
authors.lastname: Zidi
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000502:physiology*; D017536:Carotid Artery, Common / Q000502:physiology*; D003198:Computer Simulation; D055119:Elastic Modulus; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008955:Models, Cardiovascular; D033081:Shear Strength; D013314:Stress, Mechanical; D014655:Vascular Resistance