Period doubling cascades of limit cycles in cardiac action potential models as precursors to chaotic early Afterdepolarizations.

ABSTRACT:

Background

Early afterdepolarizations (EADs) are pathological voltage oscillations during the repolarization phase of cardiac action potentials (APs). EADs are caused by drugs, oxidative stress or ion channel disease, and they are considered as potential precursors to cardiac arrhythmias in recent attempts to redefine the cardiac drug safety paradigm. The irregular behaviour of EADs observed in experiments has been previously attributed to chaotic EAD dynamics under periodic pacing, made possible by a homoclinic bifurcation in the fast subsystem of the deterministic AP system of differential equations.

Results

In this article we demonstrate that a homoclinic bifurcation in the fast subsystem of the action potential model is neither a necessary nor a sufficient condition for

SUBMITTER: Kugler P 

PROVIDER: S-EPMC5379775 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature