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Title: Coexisting chaotic and multi-periodic dynamics in a model of cardiac alternans

Abstract

The spatiotemporal dynamics of cardiac tissue is an active area of research for biologists, physicists, and mathematicians. Of particular interest is the study of period-doubling bifurcations and chaos due to their link with cardiac arrhythmogenesis. In this paper, we study the spatiotemporal dynamics of a recently developed model for calcium-driven alternans in a one dimensional cable of tissue. In particular, we observe in the cable coexistence of regions with chaotic and multi-periodic dynamics over wide ranges of parameters. We study these dynamics using global and local Lyapunov exponents and spatial trajectory correlations. Interestingly, near nodes—or phase reversals—low-periodic dynamics prevail, while away from the nodes, the dynamics tend to be higher-periodic and eventually chaotic. Finally, we show that similar coexisting multi-periodic and chaotic dynamics can also be observed in a detailed ionic model.

Authors:
 [1];  [2]
  1. Departament d'Enginyeria Informàtica i Matemàtiques, Universitat Rovira i Virgili, 43007 Tarragona (Spain)
  2. Department of Applied Mathematics, University of Colorado, Boulder, Colorado 80309 (United States)
Publication Date:
OSTI Identifier:
22402513
Resource Type:
Journal Article
Resource Relation:
Journal Name: Chaos (Woodbury, N. Y.); Journal Volume: 24; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 60 APPLIED LIFE SCIENCES; ANIMAL TISSUES; BIFURCATION; CALCIUM; CARDIOVASCULAR SYSTEM; CHAOS THEORY; CORRELATIONS; KINETICS; LYAPUNOV METHOD; ONE-DIMENSIONAL CALCULATIONS; PERIODICITY; TIME DEPENDENCE

Citation Formats

Skardal, Per Sebastian, E-mail: skardals@gmail.com, and Restrepo, Juan G., E-mail: juanga@colorado.edu. Coexisting chaotic and multi-periodic dynamics in a model of cardiac alternans. United States: N. p., 2014. Web. doi:10.1063/1.4901728.
Skardal, Per Sebastian, E-mail: skardals@gmail.com, & Restrepo, Juan G., E-mail: juanga@colorado.edu. Coexisting chaotic and multi-periodic dynamics in a model of cardiac alternans. United States. doi:10.1063/1.4901728.
Skardal, Per Sebastian, E-mail: skardals@gmail.com, and Restrepo, Juan G., E-mail: juanga@colorado.edu. Mon . "Coexisting chaotic and multi-periodic dynamics in a model of cardiac alternans". United States. doi:10.1063/1.4901728.
@article{osti_22402513,
title = {Coexisting chaotic and multi-periodic dynamics in a model of cardiac alternans},
author = {Skardal, Per Sebastian, E-mail: skardals@gmail.com and Restrepo, Juan G., E-mail: juanga@colorado.edu},
abstractNote = {The spatiotemporal dynamics of cardiac tissue is an active area of research for biologists, physicists, and mathematicians. Of particular interest is the study of period-doubling bifurcations and chaos due to their link with cardiac arrhythmogenesis. In this paper, we study the spatiotemporal dynamics of a recently developed model for calcium-driven alternans in a one dimensional cable of tissue. In particular, we observe in the cable coexistence of regions with chaotic and multi-periodic dynamics over wide ranges of parameters. We study these dynamics using global and local Lyapunov exponents and spatial trajectory correlations. Interestingly, near nodes—or phase reversals—low-periodic dynamics prevail, while away from the nodes, the dynamics tend to be higher-periodic and eventually chaotic. Finally, we show that similar coexisting multi-periodic and chaotic dynamics can also be observed in a detailed ionic model.},
doi = {10.1063/1.4901728},
journal = {Chaos (Woodbury, N. Y.)},
number = 4,
volume = 24,
place = {United States},
year = {Mon Dec 15 00:00:00 EST 2014},
month = {Mon Dec 15 00:00:00 EST 2014}
}
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