title: Ex Vivo Methods for Informing Computational Models of the Mitral Valve.
abstract: Computational modeling of the mitral valve (MV) has potential applications for determining optimal MV repair techniques and risk of recurrent mitral regurgitation. Two key concerns for informing these models are (1) sensitivity of model performance to the accuracy of the input geometry, and, (2) acquisition of comprehensive data sets against which the simulation can be validated across clinically relevant geometries. Addressing the first concern, ex vivo micro-computed tomography (microCT) was used to image MVs at high resolution (~40 micron voxel size). Because MVs distorted substantially during static imaging, glutaraldehyde fixation was used prior to microCT. After fixation, MV leaflet distortions were significantly smaller (p < 0.005), and detail of the chordal tree was appreciably greater. Addressing the second concern, a left heart simulator was designed to reproduce MV geometric perturbations seen in vivo in functional mitral regurgitation and after subsequent repair, and maintain compatibility with microCT. By permuting individual excised ovine MVs (n = 5) through each state (healthy, diseased and repaired), and imaging with microCT in each state, a comprehensive data set was produced. Using this data set, work is ongoing to construct and validate high-fidelity MV biomechanical models. These models will seek to link MV function across clinically relevant states.
authors.affiliation: Cardiovascular Fluid Mechanics Laboratory, Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 387 Technology Circle NW, Suite 200, Atlanta, GA, 30313, USA.
authors.forename: Charles H
authors.initials: CH
authors.lastname: Bloodworth
authors.affiliation: Cardiovascular Fluid Mechanics Laboratory, Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 387 Technology Circle NW, Suite 200, Atlanta, GA, 30313, USA.
authors.forename: Eric L
authors.initials: EL
authors.lastname: Pierce
authors.affiliation: Cardiovascular Fluid Mechanics Laboratory, Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 387 Technology Circle NW, Suite 200, Atlanta, GA, 30313, USA.
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Easley
authors.affiliation: Center for Cardiovascular Simulation, Institute for Computational Engineering and Sciences, The University of Texas at Austin, 201 E. 24th Street, Austin, TX, 78712, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Drach
authors.affiliation: Center for Cardiovascular Simulation, Institute for Computational Engineering and Sciences, The University of Texas at Austin, 201 E. 24th Street, Austin, TX, 78712, USA.
authors.forename: Amir H
authors.initials: AH
authors.lastname: Khalighi
authors.affiliation: Cardiovascular Fluid Mechanics Laboratory, Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 387 Technology Circle NW, Suite 200, Atlanta, GA, 30313, USA.
authors.forename: Milan
authors.initials: M
authors.lastname: Toma
authors.affiliation: Cardiovascular Fluid Mechanics Laboratory, Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 387 Technology Circle NW, Suite 200, Atlanta, GA, 30313, USA.
authors.forename: Morten O
authors.initials: MO
authors.lastname: Jensen
authors.affiliation: Center for Cardiovascular Simulation, Institute for Computational Engineering and Sciences, The University of Texas at Austin, 201 E. 24th Street, Austin, TX, 78712, USA.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Sacks
authors.affiliation: Cardiovascular Fluid Mechanics Laboratory, Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 387 Technology Circle NW, Suite 200, Atlanta, GA, 30313, USA. ajit.yoganathan@bme.gatech.edu.
authors.forename: Ajit P
authors.initials: AP
authors.lastname: Yoganathan
mesh_terms: D000818:Animals; D008943:Mitral Valve / Q000000981:diagnostic imaging / Q000503:physiopathology; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging / Q000503:physiopathology; D008955:Models, Cardiovascular; D012756:Sheep; D055114:X-Ray Microtomography
keywords: Cardiovascular; Imaging; Micro-computed tomography; Mitral regurgitation; Mitral repair; Simulation