[Cardiac arrhythmias caused by electrolyte imbalance].
Cardiac arrhythmias are known to be caused by many factors. Among them, electrolyte imbalance is the most important because of electrical activity of the heart is composed of transmembrane fluxes of Na+, Ca2+ and K+. In this review article, we describe the effects of high or low concentrations of these electrolytes on the active and passive electrical properties of the membrane in the cardiac tissues, and the mechanisms by which these electrolytes cause abnormal impulse formation and conduction in the heart. Antagonism and synergism of electrolytes and pathological conditions such as digitalis intoxication and ischemia are discussed with respect to not only cardiac electrophysiology but also cellular metabolism. A pathophysiological role of Mg2+ to maintain normal excitation and conduction of the heart is also pointed out.
Nishimura
M
M
First Department of Medicine, Teikyo University School of Medicine.
Nakayama
K
K
Ishikawa
Y
Y
D000200:Action Potentials; D001145:Arrhythmias, Cardiac / Q000209:etiology*; D004562:Electrocardiography; D004573:Electrolytes / Q000378:metabolism; D004594:Electrophysiology; D006329:Heart Conduction System / Q000502:physiology; D006801:Humans; D009206:Myocardium / Q000378:metabolism; D014883:Water-Electrolyte Imbalance / Q000150:complications*
D004573:Electrolytes