title: Analysis of viscoelastic wall properties in ovine arteries.
abstract: In this paper, we analyze how elastic and viscoelastic properties differ across seven locations along the large arteries in 11 sheep. We employ a two-parameter elastic model and a four-parameter Kelvin viscoelastic model to analyze experimental measurements of vessel diameter and blood pressure obtained in vitro at conditions mimicking in vivo dynamics. Elastic and viscoelastic wall properties were assessed via solutions to the associated inverse problem. We use sensitivity analysis to rank the model parameters from the most to the least sensitive, as well as to compute standard errors and confidence intervals. Results reveal that elastic properties in both models (including Young's modulus and the viscoelastic relaxation parameters) vary across locations (smaller arteries are stiffer than larger arteries). We also show that for all locations, the inclusion of viscoelastic behavior is important to capture pressure-area dynamics.
authors.affiliation: Department of Mathematics, North Carolina State University, Raleigh, NC 27695 USA.
authors.forename: Daniela
authors.initials: D
authors.lastname: Valdez-Jasso
authors.forename: Mansoor A
authors.initials: MA
authors.lastname: Haider
authors.forename: H T
authors.initials: HT
authors.lastname: Banks
authors.forename: Daniel
authors.initials: D
authors.lastname: Bia Santana
authors.forename: Yanina
authors.initials: Y
authors.lastname: Zócalo Germán
authors.forename: Ricardo L
authors.initials: RL
authors.lastname: Armentano
authors.forename: Mette S
authors.initials: MS
authors.lastname: Olufsen
mesh_terms: D000465:Algorithms; D000818:Animals; D001158:Arteries / Q000502:physiology*; D001696:Biomechanical Phenomena / Q000502:physiology*; D001794:Blood Pressure; D004548:Elasticity; D004867:Equipment Design; D008297:Male; D008955:Models, Cardiovascular; D017711:Nonlinear Dynamics; D012680:Sensitivity and Specificity; D012756:Sheep; D012815:Signal Processing, Computer-Assisted; D014783:Viscosity