title: Mechano-electric feedback in one-dimensional model of myocardium.
abstract: We utilized our earlier developed 1D mathematical model of the heart muscle strand to study contribution of the bilateral interactions between excitation and contraction on the cellular and tissue levels to the local and global myocardium function. Numerical experiments on the model showed that an initially uniform strand, formed on the inherently identical cells, became functionally heterogeneous due to the asynchronous excitation via the electrical wave spread. Mechanical interactions between the cells and the mechano-electric feedback beat-to-beat affect the functional characteristics of coupled cardiomyocytes further, adjusting their electrical and mechanical heterogeneity to the activation timing. Model simulations showed that functional heterogeneity increases with an enlarged spatial extension of the myocardial strand (in terms of the longer slack length not a higher stretch of the strand), demonstrating a special role of the heart size in its function. Model analysis suggests that cooperative mechanisms of myofilament calcium activation contribute essentially to the generation of cellular functional heterogeneity in contracting cardiac tissue.
authors.affiliation: Laboratory of Mathematical Physiology, Institute of Immunology and Physiology, Ekaterinburg, Russia. n.vikulova@iip.uran.ru.|Ural Federal University, Ekaterinburg, Russia. n.vikulova@iip.uran.ru.
authors.forename: Nathalie A
authors.identifier: 0000-0003-1316-4437
authors.initials: NA
authors.lastname: Vikulova
authors.affiliation: Laboratory of Mathematical Physiology, Institute of Immunology and Physiology, Ekaterinburg, Russia.|Ural Federal University, Ekaterinburg, Russia.
authors.forename: Leonid B
authors.initials: LB
authors.lastname: Katsnelson
authors.affiliation: Laboratory of Mathematical Physiology, Institute of Immunology and Physiology, Ekaterinburg, Russia.|Ural Federal University, Ekaterinburg, Russia.
authors.forename: Alexander G
authors.initials: AG
authors.lastname: Kursanov
authors.affiliation: Laboratory of Mathematical Physiology, Institute of Immunology and Physiology, Ekaterinburg, Russia.|Ural Federal University, Ekaterinburg, Russia.
authors.forename: Olga
authors.initials: O
authors.lastname: Solovyova
authors.affiliation: Laboratory of Mathematical Physiology, Institute of Immunology and Physiology, Ekaterinburg, Russia.|Ural Federal University, Ekaterinburg, Russia.
authors.forename: Vladimir S
authors.initials: VS
authors.lastname: Markhasin
mesh_terms: D001696:Biomechanical Phenomena; D003198:Computer Simulation; D055590:Electromagnetic Phenomena; D025461:Feedback, Physiological / Q000502:physiology*; D006801:Humans; D008954:Models, Biological; D009200:Myocardial Contraction / Q000502:physiology*; D009206:Myocardium; D032383:Myocytes, Cardiac / Q000502:physiology
keywords: Cardiac excitation-contraction coupling; Heterogeneous myocardium; Mathematical modeling; Mechano-electric feedback