Modelling the heart as a communication system.
Electrical communication between cardiomyocytes can be perturbed during arrhythmia, but these perturbations are not captured by conventional electrocardiographic metrics. We developed a theoretical framework to quantify electrical communication using information theory metrics in two-dimensional cell lattice models of cardiac excitation propagation. The time series generated by each cell was coarse-grained to 1 when excited or 0 when resting. The Shannon entropy for each cell was calculated from the time series during four clinically important heart rhythms: normal heartbeat, anatomical reentry, spiral reentry and multiple reentry. We also used mutual information to perform spatial profiling of communication during these cardiac arrhythmias. We found that information sharing between cells was spatially heterogeneous. In addition, cardiac arrhythmia significantly impacted information sharing within the heart. Entropy localized the path of the drifting core of spiral reentry, which could be an optimal target of therapeutic ablation. We conclude that information theory metrics can quantitatively assess electrical communication among cardiomyocytes. The traditional concept of the heart as a functional syncytium sharing electrical information cannot predict altered entropy and information sharing during complex arrhythmia. Information theory metrics may find clinical application in the identification of rhythm-specific treatments which are currently unmet by traditional electrocardiographic techniques.
Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA hashika1@jhmi.edu.
Hiroshi
http://orcid.org/0000-0003-3689-6892
H
Ashikaga
Institute of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland Swiss Institute of Bioinformatics, Lausanne, Switzerland.
José
http://orcid.org/0000-0001-7622-5482
J
Aguilar-Rodríguez
Department of Economics, University of Utah, Salt Lake City, UT, USA.
Shai
http://orcid.org/0000-0002-5755-718X
S
Gorsky
Department of Surgery, University of Minnesota, Minneapolis, MN, USA.
Elizabeth
E
Lusczek
Departmento de Ecologia, Universidade de São Paulo, São Paulo, Brazil.
Flávia Maria Darcie
FM
Marquitti
Greenbelt, MD, USA.
Brian
B
Thompson
Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, HKSAR, China.
Degang
http://orcid.org/0000-0002-2326-0468
D
Wu
Department of Computer Science, University of Colorado, Boulder, CO, USA.
Joshua
J
Garland
D002450:Cell Communication / Q000502:physiology*; D004594:Electrophysiology; D006321:Heart / Q000502:physiology*; D006329:Heart Conduction System / Q000502:physiology*; D006801:Humans; D008955:Models, Cardiovascular; D032383:Myocytes, Cardiac / Q000502:physiology*
cardiac arrhythmia; cardiac electrophysiology; information theory; mathematical modelling