title: Electrophysiologic and antiarrhythmic effects of magnesium in patients with inducible ventricular tachyarrhythmia.
abstract: Intravenous magnesium is reported to be effective in the treatment of ventricular arrhythmias associated with hypomagnesemia, digitalis toxicity, or prolongation of the QT interval. In most previous reports, magnesium was added to conventional antiarrhythmic drugs that had failed. There are few data on the antiarrhythmic efficacy of magnesium as monotherapy in patients without these associated abnormalities. Ten patients with life-threatening ventricular arrhythmia and inducible ventricular tachyarrhythmia by programmed electrophysiologic testing were treated with intravenous magnesium. Following magnesium infusion, all patients still had inducible ventricular tachyarrhythmia. Moreover, magnesium therapy was not associated with significant changes in ventricular refractory period or in the morphology, cycle length, or hemodynamic response to induced ventricular tachycardia. These data suggest that intravenous magnesium has no significant electrophysiologic or antiarrhythmic effects in patients with life-threatening ventricular arrhythmia and inducible ventricular tachyarrhythmia.
authors.affiliation: Department of Internal Medicine, St. Louis University Medical Center, Missouri.
authors.forename: T C
authors.initials: TC
authors.lastname: Hilton
authors.forename: C
authors.initials: C
authors.lastname: Fredman
authors.forename: D J
authors.initials: DJ
authors.lastname: Holt
authors.forename: P
authors.initials: P
authors.lastname: Bjerregaard
authors.forename: G H
authors.initials: GH
authors.lastname: Ira
authors.forename: D L
authors.initials: DL
authors.lastname: Janosik
mesh_terms: D000368:Aged; D004594:Electrophysiology; D006329:Heart Conduction System / Q000187:drug effects*; D006801:Humans; D008278:Magnesium Sulfate / Q000494:pharmacology* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D013610:Tachycardia / Q000188:drug therapy* / Q000503:physiopathology; D014693:Ventricular Fibrillation / Q000188:drug therapy* / Q000503:physiopathology
chemical_list: D008278:Magnesium Sulfate