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Analysis of Cardiac Contractile Dysfunction and Ca2+ Transients in Rodent Myocytes
Published on: May 25, 2022
Nonlinear dynamics of paced cardiac cells
Yohannes Shiferaw1, Zhilin Qu, Alan Garfinkel
1Division of Cardiology, David Geffen School of Medicine at UCLA, University of California-Los Angeles, Los Angeles, CA 90095, USA.
Annals of the New York Academy of Sciences
|November 30, 2006
Summary
Rapidly paced cardiac cells can alternate beat-to-beat, a phenomenon linked to arrhythmias. Mathematical models using iterated maps help understand these alternans in action potential duration and calcium transients.
Area of Science:
- Cardiology
- Biophysics
- Mathematical Biology
Background:
- Cardiac cells exhibit beat-to-beat alternations in action potential duration (APD) and intracellular calcium transients when rapidly paced.
- This cellular-level dynamical instability is associated with the development of cardiac arrhythmias.
- Nonlinear dynamics principles have been increasingly applied to understand cardiac electrophysiology.
Purpose of the Study:
- To review mathematical approaches for describing the mechanisms underlying cardiac alternans.
- To explain the development and properties of beat-to-beat iterated maps for modeling alternans.
- To demonstrate the utility of iterated maps in understanding voltage and calcium instabilities in paced cardiac cells.
Main Methods:
- Review of mathematical literature on cardiac alternans.
- Explanation of beat-to-beat iterated map construction and characteristics.
- Application of these maps to model dynamical instabilities in cardiac cells.
Main Results:
- Iterated maps provide a framework for analyzing the dynamics of APD and calcium transients.
- These models elucidate the mechanisms driving beat-to-beat alternations.
- The framework successfully captures voltage and calcium instabilities in paced cardiac cells.
Conclusions:
- Beat-to-beat iterated maps are a powerful tool for understanding cardiac alternans.
- Mathematical modeling offers insights into the cellular basis of arrhythmias.
- This approach advances the application of nonlinear dynamics in cardiology.
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