Is hypomagnesemia arrhythmogenic?

Abstract

An understanding of the role of magnesium in cardiac conduction is complicated by the multiplicity of intracellular events coordinated by the magnesium ion. Several reports have cited magnesium deficiency as the cause of a variety of ventricular and supraventricular arrhythmias. On further inspection, the circumstances of each report strongly suggest the coexistence of significant potassium depletion; isolated hypomagnesemia as a cause of arrhythmia is not reported. This discussion brings together new data from basic science with that of clinical research to refute the suggestion that isolated hypomagnesemia is arrhythmogenic. However, there is sufficient evidence to indicate that hypomagnesemia will significantly exacerbate the proarrhythmic effect of hypokalemia, particularly if occurring in the presence of digoxin toxicity. Potassium and magnesium depletion are commonly concomitant, and simultaneous repletion of both ions in the presence of hypokalemia-induced arrhythmia would be both logical and effective. The beneficial effects of intravenous magnesium in the acute control of ventricular tachyarrhythmia are concluded to occur as a result of a separate antiarrhythmic action, quite independent of underlying magnesium balance.

• Authors: T A Millane, D E Ward, A J Camm
• Journal: Clinical cardiology (Clin Cardiol) Vol. 15 Issue 2 Pg. 103-8 (Feb 1992) ISSN: 0160-9289 [Print] United States
• PMID: 1371093 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Review)

Chemical References

• Ion Channels
• Magnesium
• Potassium

Topics

• Arrhythmias, Cardiac (complications, drug therapy)
• Cell Membrane Permeability
• Heart Conduction System (physiology)
• Humans
• Hypokalemia (complications)
• Intracellular Membranes
• Ion Channels (metabolism)
• Magnesium (metabolism, physiology, therapeutic use)
• Magnesium Deficiency (complications)
• Myocardium (cytology, metabolism)
• Potassium (metabolism)