title: Sensitivity of left ventricular mechanics to myofiber architecture: A finite element study.
abstract: The goal of this study was to investigate the sensitivity of computational models of the heart to their incorporated myofiber architecture during diastole. This architecture plays a critical role in the mechanical and electrical function of the heart and changes after myocardial tissue remodeling, which is associated with some of the most common heart diseases. In this study, a left ventricular finite element model of the porcine heart was created using magnetic resonance imaging, which represents the in vivo geometry. Various myofiber architectures were assigned to the finite element mesh, in the form of fiber and sheet angles. A structural-based material law was used to model the behavior of passive myocardium and its parameters were estimated using measured in vivo strains and cavity volume from magnetic resonance imaging. The final results showed noticeable sensitivity of the stress distribution to both the fiber and sheet angle distributions. This implies that a structural-based material law that takes into account the effect of both fiber and sheet angle distributions should be used. The results also show that although the simulation results improve using available data from histological studies of myocardial structure, the need for individualized myofiber architecture data is crucial.
authors.affiliation: Department of Mechanical Engineering, University of Kentucky, Lexington, KY, USA.
authors.forename: Amir
authors.initials: A
authors.lastname: Nikou
authors.affiliation: Gorman Cardiovascular Research Group and Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Gorman
authors.affiliation: Department of Mechanical Engineering, University of Kentucky, Lexington, KY, USA Department of Surgery, University of Kentucky, Lexington, KY, USA wenk@engr.uky.edu.
authors.forename: Jonathan F
authors.initials: JF
authors.lastname: Wenk
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D003198:Computer Simulation; D020342:Finite Element Analysis; D006352:Heart Ventricles / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008953:Models, Anatomic; D023421:Models, Animal; D008955:Models, Cardiovascular; D013552:Swine; D016277:Ventricular Function, Left / Q000502:physiology*
keywords: Myofiber architecture; numerical modeling; passive myocardium; stress distribution