title: Fluid-structure interaction and structural analyses using a comprehensive mitral valve model with 3D chordal structure.
abstract: Over the years, three-dimensional models of the mitral valve have generally been organized around a simplified anatomy. Leaflets have been typically modeled as membranes, tethered to discrete chordae typically modeled as one-dimensional, non-linear cables. Yet, recent, high-resolution medical images have revealed that there is no clear boundary between the chordae and the leaflets. In fact, the mitral valve has been revealed to be more of a webbed structure whose architecture is continuous with the chordae and their extensions into the leaflets. Such detailed images can serve as the basis of anatomically accurate, subject-specific models, wherein the entire valve is modeled with solid elements that more faithfully represent the chordae, the leaflets, and the transition between the two. These models have the potential to enhance our understanding of mitral valve mechanics and to re-examine the role of the mitral valve chordae, which heretofore have been considered to be 'invisible' to the fluid and to be of secondary importance to the leaflets. However, these new models also require a rethinking of modeling assumptions. In this study, we examine the conventional practice of loading the leaflets only and not the chordae in order to study the structural response of the mitral valve apparatus. Specifically, we demonstrate that fully resolved 3D models of the mitral valve require a fluid-structure interaction analysis to correctly load the valve even in the case of quasi-static mechanics. While a fluid-structure interaction mode is still more computationally expensive than a structural-only model, we also show that advances in GPU computing have made such models tractable. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Technology Enterprise Park, Suite 200, 387 Technology Circle, Atlanta, 30313-2412, GA, U.S.A.
authors.forename: Milan
authors.initials: M
authors.lastname: Toma
authors.affiliation: Department of Mechanical Engineering, St. Martin's University, 5000 Abbey Way SE, Lacey, 98503, WA, U.S.A.
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Einstein
authors.affiliation: Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Technology Enterprise Park, Suite 200, 387 Technology Circle, Atlanta, 30313-2412, GA, U.S.A.
authors.forename: Charles H
authors.initials: CH
authors.lastname: Bloodworth
authors.affiliation: Department of Mechanical Engineering, University of Maine, 219 Boardman Hall, Orono, 04469-5711, ME, U.S.A.
authors.forename: Richard P
authors.initials: RP
authors.lastname: Cochran
authors.affiliation: Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Technology Enterprise Park, Suite 200, 387 Technology Circle, Atlanta, 30313-2412, GA, U.S.A.
authors.forename: Ajit P
authors.initials: AP
authors.lastname: Yoganathan
authors.affiliation: Department of Mechanical Engineering, University of Maine, 219 Boardman Hall, Orono, 04469-5711, ME, U.S.A.
authors.forename: Karyn S
authors.initials: KS
authors.lastname: Kunzelman
mesh_terms: D002815:Chordae Tendineae / Q000033:anatomy & histology / Q000502:physiology; D003198:Computer Simulation; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008943:Mitral Valve / Q000033:anatomy & histology* / Q000502:physiology*; D008953:Models, Anatomic
keywords: chordae tendineae; chordal structure; comprehensive computational model; fluid-structure interaction; forces; mitral valve; papillary muscle