Mexiletine: Antiarrhythmic mechanisms, emerging clinical applications and mortality

Pacing Clin Electrophysiol. 2023 Nov;46(11):1348-1356. doi: 10.1111/pace.14846. Epub 2023 Oct 17.

Abstract

Mexiletine, a class Ib antiarrhythmic drug, exhibits its major antiarrhythmic effect via inhibition of the fast and late Na+ currents in myocardial tissues that are dependent on the opening of Na+ channels for their excitation. Through a comprehensive examination of mexiletine's therapeutic benefits and potential risks, we aim to provide valuable insights that reinforce its role as a vital therapeutic option for patients with ventricular arrhythmias, long QT syndrome, and other heart rhythm disorders. This review will highlight the current understandings of the antiarrhythmic effects and rationales for recent off-label use and address the mortality and proarrhythmic effects of mexiletine utilizing published basic and clinical studies over the past five decades.

Keywords: antiarrhythmic effects; atrial fibrillation; drug safety; long QT syndrome; mexiletine; mortality; pharmacokinetics; proarrhythmias; ventricular tachycardia.

Publication types

  • Review

MeSH terms

  • Anti-Arrhythmia Agents* / pharmacology
  • Anti-Arrhythmia Agents* / therapeutic use
  • Arrhythmias, Cardiac / drug therapy
  • Humans
  • Long QT Syndrome*
  • Mexiletine / pharmacology
  • Mexiletine / therapeutic use
  • Myocardium

Substances

  • Anti-Arrhythmia Agents
  • Mexiletine