Generation Mechanism of Alternans in Luo-Rudy Model

Hiroyuki Kitajima, Eri Ioka, Toru Yazawa

Research output: Research - peer-reviewArticle

Abstract

Electrical alternans is the alternating amplitude from beat to beat in the action potential of the cardiac cell. It has been associated with ventricular arrhythmias in many clinical studies; however, its dynamical mechanisms remain unknown. The reason is that we do not have realistic network models of the heart system. Recently, Yazawa clarified the network structure of the heart and the central nerve system in the crustacean heart. In this study, we construct a simple model of the heart system based on Yazawa's experimental data. Using this model, we clarify that two parameters (the conductance of sodium ions and free concentration of potassium ions in the extracellular compartment) play the key roles of generating alternans. In particular, we clarify that the inactivation gate of the time-independent potassium channel is the most important parameter. Moreover, interaction between the membrane potential and potassium ionic currents is significant for generating alternate rhythms. This result indicates that if the muscle cell has problems such as channelopathies, there is great risk of generating alternans.

LanguageEnglish
Article number1650075
JournalInternational Journal of Bifurcation and Chaos
Volume26
Issue number5
DOIs
StatePublished - 2016 May 1
Externally publishedYes

Fingerprint

Potassium
Ions
Muscle
Cells
Sodium
Membranes

Keywords

  • Alternans
  • bifurcation

ASJC Scopus subject areas

  • Modelling and Simulation
  • Engineering(all)
  • General
  • Applied Mathematics

Cite this

Generation Mechanism of Alternans in Luo-Rudy Model. / Kitajima, Hiroyuki; Ioka, Eri; Yazawa, Toru.

In: International Journal of Bifurcation and Chaos, Vol. 26, No. 5, 1650075, 01.05.2016.

Research output: Research - peer-reviewArticle

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