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Class 1C Antiarrhythmics for Premature Ventricular Complex Suppression in Nonischemic Cardiomyopathy With Implantable

Mohamad Raad1, Haran Yogasundaram1, Justice Oranefo1

  • 1Electrophysiology Section, Division of Cardiovascular Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA.

JACC. Clinical Electrophysiology
|March 29, 2024
PubMed

Insights

Class 1C antiarrhythmic drugs (AADs) effectively reduced premature ventricular complexes (PVCs) in patients with nonischemic cardiomyopathy and ICDs. This approach improved heart function and was found to be safe in this patient group.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Pharmacology

Background:

  • Premature ventricular complexes (PVCs) are prevalent in heart failure patients, correlating with adverse outcomes.
  • Current guidelines restrict Class 1C antiarrhythmic drugs (AADs) in structural heart disease despite their efficacy in PVC suppression.

Purpose of the Study:

  • To evaluate the safety and effectiveness of Class 1C AADs in patients diagnosed with nonischemic cardiomyopathy (NICM) who also have implantable cardioverter-defibrillators (ICDs).

Main Methods:

  • A retrospective analysis of 34 NICM patients with ICDs treated with flecainide or propafenone from 2014-2022.
  • Comparison of PVC burden, left ventricular ejection fraction (LVEF), and biventricular pacing percentage before and during Class 1C AAD therapy.
  • Assessment of safety outcomes including arrhythmias, heart failure admissions, and mortality.

Main Results:

  • Class 1C AADs significantly reduced PVC burden from 20% to 6% (P < 0.001).
  • Left ventricular ejection fraction (LVEF) improved from 33% to 37% (P = 0.01), and biventricular pacing increased from 85% to 93% (P = 0.01).
  • Fewer sustained ventricular arrhythmias and heart failure admissions were observed during treatment compared to the prior year.

Conclusions:

  • Class 1C AADs demonstrate efficacy in suppressing PVCs for NICM patients with ICDs.
  • Treatment with these agents led to improved LVEF and biventricular pacing, with a favorable safety profile in this cohort.
  • Larger studies are warranted to confirm these findings and solidify the role of Class 1C AADs in this population.
Abstract

Keywords:
class 1C antiarrhythmic drugsimplantable cardioverter-defibrillatornonischemic cardiomyopathypremature ventricular complexes

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