Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy characterized by progressive fibro-fatty replacement of cardiomyocytes and associated with a high risk of ventricular arrhythmia (VA). Current guidelines recommend beta-blockers as first-line medical therapy and if ineffective, sotalol or amiodarone.

To describe our experience, as a tertiary center for ARVC, with the effectiveness and tolerance of flecainide in addition to beta-blockers to prevent VA in ARVC.

We retrospectively included 100 consecutive ARVC patients who received flecainide with beta-blockers between May 1999 and November 2017. Treatment persistence and related side effects were assessed, as was VA-free survival on treatment, 24-hr Holter monitoring and programmed ventricular stimulation (PVS) off- and on-treatment.

Tolerance was good, with 10% flecainide discontinuations (lack of efficacy in 6, atrial fibrillation in one and side effects in 3). No Brugada-induced electrocardiography pattern on flecainide or hemodynamic impairment was reported. Premature ventricular contraction burden at 24-hr Holter monitoring was significantly decreased under treatment (median 415 [interquartile range 97–730] vs. 2370 [1572–3400] at baseline, P<0.0001, n=46). Among the 33 patients with PVS under treatment, PVS was positive in 40% on-treatment versus 94% off-treatment (P<0.001). During a median follow-up of 47months (interquartile range 23–73), 22 patients presented sustained VA on treatment, corresponding to an event rate of 5% (95% confidence interval [0.6–9]) at 1 year and 25% (95% confidence interval [14–35]) at 5years under treatment (Fig. 1). No patient died.

This study suggests that flecainide and beta-blockers association is complementary to ICD and catheter ablation and is safe for treating persistent symptomatic VA in patients with ARVC.