Comprehensive Physiology Wiley Online Library

Ion Channels and Cardiac Arrhythmia in Heart Disease

Full Article on Wiley Online Library



Abstract

The sections in this article are:

1 Background
1.1 The Clinical Problem—Tachyrhythmia in Structural Heart Disease
1.2 Arrythmia and Mechanisms
1.3 Currents Underlying the Action Potential
1.4 The Role of Ion Channels in Arrhythmia
2 Electrophysiology of Acquired Heart Disease
2.1 Human and Animal Models for Cellular and Molecular Electrophysiology
2.2 Specific Cellular Electrophysiological Changes in Acquired Heart Disease
3 Ion Channel Changes in Acquired Heart Disease
3.1 General Considerations
3.2 Specific Ion Currents and Arrhythmia
3.3 Summary of Electrical Remodeling in Acquired Heart Disease
4 The Long Q‐T Syndrome
4.1 Introduction
4.2 Arrhythmic Mechanism
4.3 Molecular Mechanisms
4.4 Implications for Therapy
4.5 Present Status
5 Idiopathic Ventricular Fibrillation
6 Inherited Cardiomyopathy
6.1 Introduction
6.2 Clinical Picture
6.3 Arrhythmic Mechanisms
Figure 1. Figure 1.

Cardiac currents underlying the action potential and their alteration in acquired heart disease. The action potential is represented in the center, the currents are diagrammed with outward repolarized currents being upward and inward depolarizing currents as downward. The timing of each relative current amplitude in relation to the action potential is represented, but no attempt was made to represent current densities relative to other currents. Abbreviations and symbols: Nomenclature for currents is given in the text. LVH, hypertrophy; CHF, Heart failure; AF, atrial fibrillation; MI, myocardial infarction; ↑↑, consistently increased in >3 studies, ↑, usually increased in > 3 studies or increased in ≤ 3 studies; ↑↓ variably increased or decreased; NC, no change in > 3 studies; nc, no change in ≤ 3 studies; – not known. Cm, membrane capacitance as a measure of cell size; APD, action potential duration.



Figure 1.

Cardiac currents underlying the action potential and their alteration in acquired heart disease. The action potential is represented in the center, the currents are diagrammed with outward repolarized currents being upward and inward depolarizing currents as downward. The timing of each relative current amplitude in relation to the action potential is represented, but no attempt was made to represent current densities relative to other currents. Abbreviations and symbols: Nomenclature for currents is given in the text. LVH, hypertrophy; CHF, Heart failure; AF, atrial fibrillation; MI, myocardial infarction; ↑↑, consistently increased in >3 studies, ↑, usually increased in > 3 studies or increased in ≤ 3 studies; ↑↓ variably increased or decreased; NC, no change in > 3 studies; nc, no change in ≤ 3 studies; – not known. Cm, membrane capacitance as a measure of cell size; APD, action potential duration.

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Jonathan C. Makielski, Harry A. Fozzard. Ion Channels and Cardiac Arrhythmia in Heart Disease. Compr Physiol 2011, Supplement 6: Handbook of Physiology, The Cardiovascular System, The Heart: 709-740. First published in print 2002. doi: 10.1002/cphy.cp020119