Antiarrhythmic therapy and risk of cumulative ventricular arrhythmias in arrhythmogenic right ventricle cardiomyopathy.

OBJECTIVES: The aim of our study was to investigate the benefit of antiarrhythmic drugs (AAD) - beta-blockers, sotalol or amiodarone - in a cohort of Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) patients with long-term longitudinal follow up. BACKGROUND: AAD are prescribed in ARVC to prevent ventricular arrhythmias and control symptoms. However, there are no controlled clinical trials and knowledges regarding the efficacy of AAD in ARVC are limited. METHODS: The study population included 123 patients with definite diagnosis of ARVC and ≥ 2 clinical evaluations. The primary outcome was a composite of sudden cardiac death (SCD)/recurrent major ventricular arrythmias (MVA): sudden cardiac arrest, sustained ventricular tachycardia (VT) and appropriate implantable cardioverter defibrillator interventions, including recurrent events in patients with >1 MVA. Time to first event (SCD or MVA) was considered as secondary composite endpoint. RESULTS: Sixteen patients were taking AAD at baseline and 75 started at least one AAD during a median follow-up of 132 months [61-255]. A total of 37 patients experienced ≥1 MVA with a total count of 83 recurrent MVA. After adoption of a propensity score analysis, no AAD were associated with lower risk of recurrent MVA. However, if dosage of AAD was considered, beta-blockers at >50% target dose were associated with a significant reduction in the risk of MVA compared to patients not taking beta-blockers (HR 0.10, 95% CI 0.02-0.46, p = 0.004). CONCLUSIONS: In a large cohort of ARVC patients with a long-term follow-up, only beta-blockers administrated at >50% target dose were associated with lower risk of SCD/recurrent MVA.