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The Dynamics of Sustained Reentry in a Loop Model with Discrete Gap Junction Resistance

Wei Chen·Mark Potse·Alain Vinet
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Abstract

Dynamics of reentry are studied in a one dimensional loop of model cardiac cells with discrete intercellular gap junction resistance ($R$). Each cell is represented by a continuous cable with ionic current given by a modified Beeler-Reuter formulation. For $R$ below a limiting value, propagation is found to change from period-1 to quasi-periodic ($QP$) at a critical loop length ($L_{crit}$) that decreases with $R$. Quasi-periodic reentry exists from $L_{crit}$ to a minimum length ($L_{min}$) that is also shortening with $R$. The decrease of $L_{crit}(R)$ is not a simple scaling, but the bifurcation can still be predicted from the slope of the restitution curve giving the duration of the action potential as a function of the diastolic interval. However, the shape of the restitution curve changes with $R$.

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Wei Chen, Mark Potse, Alain Vinet. 2007-03-25. The Dynamics of Sustained Reentry in a Loop Model with Discrete Gap Junction Resistance. https://doi.org/10.1103/physreve.76.021928

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