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Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents
10:53

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents

Published on: July 3, 2013

[New anti-arrhythmia agents]

P Honerjäger1, G Schmidt

  • 1Institut für Pharmakologie und Toxikologie, Technischen Universität München.

Zeitschrift Fur Kardiologie
|January 1, 1992
PubMed

Insights

Class-I antiarrhythmic drugs increase mortality in post-myocardial infarction patients and should be avoided. Other antiarrhythmic agents show potential but require further clinical trials for safety and efficacy in cardiac arrhythmias.

Area of Science:

  • Cardiology
  • Pharmacology
  • Clinical Trials

Background:

  • Class-I antiarrhythmic agents (encainide, flecainide, moricizine) are used for ventricular premature depolarizations.
  • Symptomatic tachyarrhythmias require careful risk-benefit assessment for class-I agents.
  • New class-I drug development appears unpromising.

Purpose of the Study:

  • Evaluate the efficacy and safety of antiarrhythmic agents.
  • Assess the impact of antiarrhythmic drugs on mortality after myocardial infarction.
  • Explore potential treatments for supraventricular and ventricular arrhythmias.

Main Methods:

  • Review of clinical trials and pharmacological profiles of antiarrhythmic drugs.
  • Analysis of mortality data in post-myocardial infarction patients treated with class-I agents.
  • Preclinical and clinical evaluation of class-III antiarrhythmic agents.

Main Results:

  • Class-I agents increase mortality in asymptomatic post-myocardial infarction patients.
  • Esmolol is an effective intravenous beta-blocker for supraventricular arrhythmias.
  • Class-III agents (sematilide, dofetilide) show preclinical efficacy but require clinical validation; torsades de pointes is a risk.

Conclusions:

  • Avoid class-I antiarrhythmics in asymptomatic post-MI patients.
  • Amiodarone and sotalol show promise for improving survival in patients at risk of sudden cardiac death.
  • Further controlled trials are needed to establish the clinical value of new antiarrhythmic agents.

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