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arXiv · 1408.4993

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

Per Sebastian Skardal·Juan G. Restrepo
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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.

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Per Sebastian Skardal, Juan G. Restrepo. 2014-10-18. Coexisting chaotic and multi-periodic dynamics in a model of cardiac alternans. https://doi.org/10.1063/1.4901728

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