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Broad antiarrhythmic effect of mexiletine in different arrhythmia models

Gerrit Frommeyer1, Jonas Garthmann1, Christian Ellermann1

  • 1Division of Electrophysiology, Department of Cardiovascular Medicine, University of Münster, Albert-Schweitzer Campus 1, Münster, Germany.

Europace : European Pacing, Arrhythmias, and Cardiac Electrophysiology : Journal of the Working Groups on Cardiac Pacing, Arrhythmias, and Cardiac Cellular Electrophysiology of the European Society of Cardiology
|October 11, 2017
PubMed
Abstract

Insights

Mexiletine effectively reduced ventricular tachycardia in long-QT syndromes and suppressed ventricular fibrillation in short-QT syndrome. This antiarrhythmic drug also demonstrated efficacy in preventing atrial fibrillation.

Area of Science:

  • Cardiology
  • Pharmacology
  • Electrophysiology

Background:

  • Mexiletine is suggested to possess antiarrhythmic properties.
  • Experimental and clinical data indicate its potential in managing various arrhythmias.

Purpose of the Study:

  • To investigate the efficacy of mexiletine in experimental models of atrial fibrillation (AF).
  • To evaluate mexiletine's effects on long-QT syndrome (LQTS) and short-QT syndrome (SQTS).

Main Methods:

  • Rabbit hearts were used to simulate LQTS with erythromycin and veratridine, and SQTS with pinacidil.
  • Mexiletine was administered to assess its impact on QT intervals, repolarization dispersion, and induced arrhythmias like torsade de pointes and ventricular fibrillation.
  • AF was induced using acetylcholine/isoproterenol, and mexiletine's effect on atrial refractoriness was measured.

Main Results:

  • Mexiletine significantly reduced QT prolongation and dispersion in LQTS models, suppressing polymorphic ventricular tachycardia.
  • In SQTS models, mexiletine reversed repolarization abnormalities and prevented ventricular fibrillation.
  • Mexiletine increased atrial refractoriness and suppressed AF induction.

Conclusions:

  • Mexiletine exhibits significant antiarrhythmic effects in pharmacologically induced LQTS, SQTS, and AF models.
  • The drug effectively reduces the incidence of life-threatening ventricular arrhythmias and atrial fibrillation.

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