title: A new simplified methodology for studying the coupled fluid-structure interaction in a weakened basilar artery.
abstract: In this paper, we study the fluid-structure interaction in a weakened basilar artery. The aim is to study how the wall shear stress changes in space and time because of the weakening, because spatial and temporal changes are thought to be possible causes of aneurysm and vascular deseases. The arterial wall, in its natural configuration, is modeled as a hyperelastic cylinder, inhomogeneous along its axis, in order to simulate the axis-symmetric weakening. The fluid is studied exploiting a recent approach for quasi-one-dimensional flows in slowly varying ducts, which allows to write the averaged equations of mass and energy balance on the basis of the velocity profile in a straight duct. The unknowns are the wall pressure, the average velocity, and the wall radial displacement. The problem is solved in two parts: first, the stationary non-linear coupled problem is solved, and an intermediate configuration is obtained. Then, we study the variation of the basic unknowns about the intermediate configuration, considering time dependence over the cardiac cycles. The results suggest that, with a 10% reduction of the main elastic modulus, the shear stress in the weakened zone changes its sign and doubles the maximum stress value detected in the healthy zone. Copyright © 2015 John Wiley & Sons, Ltd.
authors.affiliation: Dipartimento di Ingegneria Civile ed Architettura (DICAr), Università degli Studi di Pavia, Pavia, Italy.|Centro di Simulazione Numerica Avanzata (CeSNA), Istituto Universitario di Studi Superiori (IUSS), Pavia, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Montanino
authors.affiliation: Dipartimento di Ingegneria Civile (DiCiv), Università degli Studi di Salerno, Fisciano, SA, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Fortunato
authors.affiliation: Dipartimento di Ingegneria Civile (DiCiv), Università degli Studi di Salerno, Fisciano, SA, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Angelillo
mesh_terms: D000818:Animals; D001488:Basilar Artery; D001783:Blood Flow Velocity; D001794:Blood Pressure; D004548:Elasticity; D006801:Humans; D008955:Models, Cardiovascular; D013314:Stress, Mechanical
keywords: averaged equations; basilar artery; fluid-structure interaction; wall shear stress