title: An integrated electromechanical-growth heart model for simulating cardiac therapies.
abstract: An emerging class of models has been developed in recent years to predict cardiac growth and remodeling (G&R). We recently developed a cardiac G&R constitutive model that predicts remodeling in response to elevated hemodynamics loading, and a subsequent reversal of the remodeling process when the loading is reduced. Here, we describe the integration of this G&R model to an existing strongly coupled electromechanical model of the heart. A separation of timescale between growth deformation and elastic deformation was invoked in this integrated electromechanical-growth heart model. To test our model, we applied the G&R scheme to simulate the effects of myocardial infarction in a realistic left ventricular (LV) geometry using the finite element method. We also simulate the effects of a novel therapy that is based on alteration of the infarct mechanical properties. We show that our proposed model is able to predict key features that are consistent with experiments. Specifically, we show that the presence of a non-contractile infarct leads to a dilation of the left ventricle that results in a rightward shift of the pressure volume loop. Our model also predicts that G&R is attenuated by a reduction in LV dilation when the infarct stiffness is increased.
authors.affiliation: Department of Mechanical Engineering, Michigan State University, East Lansing, MI, USA. lclee@egr.msu.edu.
authors.forename: Lik Chuan
authors.initials: LC
authors.lastname: Lee
authors.affiliation: Simula Research Laboratory, Oslo, Norway.
authors.forename: Joakim
authors.initials: J
authors.lastname: Sundnes
authors.affiliation: Institute of Biomedical Engineering, ETH Zurich, Zurich, Switzerland.
authors.forename: Martin
authors.initials: M
authors.lastname: Genet
authors.affiliation: Department of Mechanical Engineering, University of Kentucky, Lexington, KY, USA.
authors.forename: Jonathan F
authors.initials: JF
authors.lastname: Wenk
authors.affiliation: Simula Research Laboratory, Oslo, Norway.
authors.forename: Samuel T
authors.initials: ST
authors.lastname: Wall
mesh_terms: D001696:Biomechanical Phenomena; D003198:Computer Simulation; D003971:Diastole / Q000502:physiology; D004548:Elasticity; D055724:Electrophysiological Phenomena; D020342:Finite Element Analysis; D006321:Heart / Q000254:growth & development*; D006801:Humans; D008955:Models, Cardiovascular; D018485:Muscle Fibers, Skeletal / Q000502:physiology; D009203:Myocardial Infarction / Q000503:physiopathology / Q000628:therapy*; D011312:Pressure; D066253:Vascular Remodeling; D016277:Ventricular Function, Left / Q000502:physiology
keywords: Bioinjection therapy; Cardiac electromechanics; Finite element modeling; Growth and remodeling; Myocardial infarction