Efficacy of antiarrhythmic drugs in arrhythmogenic right ventricular cardiomyopathy: a report from the North American ARVC Registry.
OBJECTIVE
This study sought to examine the efficacy of empiric antiarrhythmic drugs in a rigorously characterized cohort of arrhythmogenic right ventricular cardiomyopathy (ARVC) patients.


BACKGROUND
Antiarrhythmic drugs are important in protecting against ventricular arrhythmias in ARVC, but no studies have provided data in a group rigorously screened for the disease.


METHODS
Antiarrhythmic medicines were examined in all subjects with implantable cardioverter-defibrillators (ICDs) enrolled in the North American ARVC Registry. A Cox proportional hazards model was used to account for time on each drug, and a hierarchical analysis was performed for repeated measures within individuals.


RESULTS
Ninety-five patients were studied, with a mean follow-up of 480 +/- 389 days. Fifty-eight (61%) received beta-blockers, and these medicines were not associated with an increased or decreased risk of ventricular arrhythmias. Sotalol was associated with a greater risk of any clinically relevant ventricular arrhythmia as defined by sustained ventricular tachycardia or ICD therapy (hazard ratio [HR]: 2.55, 95% confidence interval [CI]: 1.02 to 6.39, p = 0.045), but this was not statistically significant after adjusting for potential confounders. An increased risk of any ICD shock and first clinically relevant ventricular arrhythmia while on sotalol remained significant after multivariable adjustment. Those on amiodarone (n = 10) had a significantly lower risk of any clinically relevant ventricular arrhythmia (HR: 0.25, 95% CI: 0.07 to 0.95, p = 0.041), a finding that remained significant after multivariable adjustment.


CONCLUSIONS
In a cohort of well-characterized ARVC subjects, neither beta-blockers nor sotalol seemed to be protective. Evidence from a small number of patients suggests that amiodarone has superior efficacy in preventing ventricular arrhythmias.
Marcus
Gregory M
GM
Division of Cardiology, Electrophysiology Section, University of California, San Francisco, CA 94143-1354, USA. marcusg@medicine.ucsf.edu
Glidden
David V
DV
Polonsky
Bronislava
B
Zareba
Wojciech
W
Smith
Lisa M
LM
Cannom
David S
DS
Estes
N A Mark
NA
Marcus
Frank
F
Scheinman
Melvin M
MM
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000328:Adult; D000638:Amiodarone / Q000627:therapeutic use; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D019571:Arrhythmogenic Right Ventricular Dysplasia / Q000150:complications* / Q000628:therapy; D003131:Combined Modality Therapy; D017147:Defibrillators, Implantable; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012042:Registries; D013015:Sotalol / Q000627:therapeutic use; D017180:Tachycardia, Ventricular / Q000209:etiology / Q000517:prevention & control*; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000209:etiology / Q000517:prevention & control*
D000319:Adrenergic beta-Antagonists; D000889:Anti-Arrhythmia Agents; D013015:Sotalol; D000638:Amiodarone