Noise-induced early afterdepolarizations in a three-dimensional cardiac action potential model

A compact three-dimensional representation of cardiac action potential (AP) properties in terms of current source is presented here. The experimental protocol used to obtain such representation is based on the measure of instantaneous current-voltage relationships during the course of the AP. The procedure, which combines current- and voltage-clamps on patch clamped cardiac myocytes, has been previously applied to real cells, and then extended to computer simulations with cellular ventricular AP models. The three-dimensional AP representation allows to easily estimate membrane resistance during repolarization, a key factor for the modulation of ventricular repolarization. It also shows that, during late ventricular repolarization, membrane conductance becomes negative, <em>i.e.</em> repolarization is auto-regenerative. The novel AP representation is therefore a useful tool for both in vivo and in silico cardiac cellular electrophysiological investigations.

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Dynamics of drug binding to the hERG channel: An in silico cardiac action potential model for early safety assessment

Journal of Pharmacological and Toxicological Methods ◽

10.1016/j.vascn.2012.08.043 ◽

2012 ◽

Vol 66 (2) ◽

pp. 171

Author(s):

Giovanni Y. Di Veroli ◽

Mark Davies ◽

Chris E. Pollard ◽

Jean-Pierre Valentin ◽

Henggui Zhang ◽

...

Keyword(s):

Action Potential ◽

In Silico ◽

Safety Assessment ◽

Potential Model ◽

Drug Binding ◽

Herg Channel ◽

Cardiac Action Potential ◽

Cardiac Action

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SIMULATION RELIABILITY OF PHYSIOLOGICAL PHENOMENA BY CARDIAC ACTION POTENTIAL MODEL

The FASEB Journal ◽

10.1096/fasebj.20.5.lb10 ◽

2006 ◽

Vol 20 (5) ◽

Author(s):

Ching‐Hsing Luo ◽

Po‐Yuan Chen ◽

Chun‐Hao Teng ◽

Ching‐Ting Lee ◽

Ruey‐Jen Sung

Keyword(s):

Action Potential ◽

Potential Model ◽

Cardiac Action Potential ◽

Cardiac Action

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Local Onset of Voltage and Calcium Alternans in the Heart

ASME 2011 Dynamic Systems and Control Conference and Bath/ASME Symposium on Fluid Power and Motion Control, Volume 2 ◽

10.1115/dscc2011-6148 ◽

2011 ◽

Author(s):

Stephen D. McIntyre ◽

Yoichiro Mori ◽

Elena G. Tolkacheva

Keyword(s):

Ventricular Fibrillation ◽

Action Potential ◽

Intracellular Calcium ◽

Cardiac Myocytes ◽

Cardiac Tissue ◽

Potential Model ◽

Cardiac Action Potential ◽

2D Simulation ◽

Cardiac Action ◽

Electrical Alternans

A beat-to-beat variation in cardiac action potential durations (APD) is a phenomenon known as electrical alternans. Alternans desynchronizes depolarization, increases dispersion of refractoriness and creates a substrate for ventricular fibrillation. In the heart, APD alternans can be accompanied by alternans in intracellular calcium ([Ca2+]i) transients. Recently, we demonstrated experimentally that the onset of APD alternans in the heart is a local phenomenon that undergoes complex spatiotemporal dynamics as pacing rate increases. Moreover, the local onset of APD alternans can be predicted by measuring the restitution properties of periodically paced cardiac tissue. The purpose of this research is to investigate the interplay between local onsets of APD and [Ca2+]i alternans using 2D simulation of action potential model of cardiac myocytes.

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