title: Analysis of passive cardiac constitutive laws for parameter estimation using 3D tagged MRI.
abstract: An unresolved issue in patient-specific models of cardiac mechanics is the choice of an appropriate constitutive law, able to accurately capture the passive behavior of the myocardium, while still having uniquely identifiable parameters tunable from available clinical data. In this paper, we aim to facilitate this choice by examining the practical identifiability and model fidelity of constitutive laws often used in cardiac mechanics. Our analysis focuses on the use of novel 3D tagged MRI, providing detailed displacement information in three dimensions. The practical identifiability of each law is examined by generating synthetic 3D tags from in silico simulations, allowing mapping of the objective function landscape over parameter space and comparison of minimizing parameter values with original ground truth values. Model fidelity was tested by comparing these laws with the more complex transversely isotropic Guccione law, by characterizing their passive end-diastolic pressure-volume relation behavior, as well as by considering the in vivo case of a healthy volunteer. These results show that a reduced form of the Holzapfel-Ogden law provides the best balance between identifiability and model fidelity across the tests considered.
authors.affiliation: Division of Imaging Sciences and Biomedical Engineering, King's College London, 4th Floor, Lambeth Wing St. Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, UK, myrianthi.hadjicharalambous@kcl.ac.uk.
authors.forename: Myrianthi
authors.initials: M
authors.lastname: Hadjicharalambous
authors.forename: Radomir
authors.initials: R
authors.lastname: Chabiniok
authors.forename: Liya
authors.initials: L
authors.lastname: Asner
authors.forename: Eva
authors.initials: E
authors.lastname: Sammut
authors.forename: James
authors.initials: J
authors.lastname: Wong
authors.forename: Gerald
authors.initials: G
authors.lastname: Carr-White
authors.forename: Jack
authors.initials: J
authors.lastname: Lee
authors.forename: Reza
authors.initials: R
authors.lastname: Razavi
authors.forename: Nicolas
authors.initials: N
authors.lastname: Smith
authors.forename: David
authors.initials: D
authors.lastname: Nordsletten
mesh_terms: D000328:Adult; D003971:Diastole; D006321:Heart / Q000502:physiology*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D008955:Models, Cardiovascular; D011312:Pressure