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Updated: Jan 2, 2026

Isolation and Functional Characterization of Human Ventricular Cardiomyocytes from Fresh Surgical Samples
Published on: April 21, 2014
Bifurcations Caused by Feedback between Voltage and Intracellular Ion Concentrations in Ventricular Myocytes
1Department of Medicine and Department of Biomathematics, University of California, Los Angeles, California 90095, USA.
Abstract:
We develop an iterated map model to describe the bifurcations and complex dynamics caused by the feedback between voltage and intracellular Ca^{2+} and Na^{+} concentrations in paced ventricular myocytes. Voltage and Ca^{2+} can form either a positive or a negative feedback loop, while voltage and Na^{+} form a negative feedback loop. Under certain diseased conditions, when the feedback between voltage and Ca^{2+} is positive, Hopf bifurcations occur, leading to periodic oscillatory behaviors. When this feedback is negative, period-doubling bifurcation routes to alternans and chaos occur.
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