Subcutaneous implantable defibrillator therapy in patients with Brugada Syndrome: data from a large multicenter registry

Background: The implantable cardioverter-defibrillator (ICD) is recognized as the most effective life-saving therapy in patients with Brugada syndrome (BrS). However, transvenous ICD is associated with a notable rate of complications over time. The subcutaneous implantable cardioverter-defibrillator (S-ICD) has emerged as a promising alternative to the transvenous ICD. Nevertheless, long-term data from large cohorts of BrS patients with S-ICDs are lacking. Objectives: This multicenter study aimed to assess the long-term outcomes of S-ICD therapy in patients with BrS. Methods: The study included 450 consecutive BrS patients (mean age 43 ± 12; 86% male) who underwent S-ICD implantation between 2014 and 2024. Results: During a median follow-up of 52 months (25th-75th percentile: 29-72), appropriate shocks were delivered in 3% of patients (1.2%; 95% CI: 0.2-2.2, at 12 months), with a first-shock success rate of 90% (100% with 2 shocks). Inappropriate shocks occurred in 7% of patients (1.4%; 95% CI: 0.3-2.5, at 12 months). Shock zone programmed at 250 beats/min (HR: 0.40; 95% CI: 0.18-0.89; P = 0.025) and more than 1 suitable vector on screening (HR: 0.39; 95% CI: 0.17-0.87; P = 0.023) were independent protective factors against inappropriate shock. Device-related complications were reported in 4% of patients (2.5%; 95% CI: 1.0-3.9 at 12 months). The need for antibradycardia pacing was reported in 3 patients (0.7%). No device explantation because of the need for antitachycardia pacing was noted. Conclusions: Our findings support the S-ICD as a viable alternative to the transvenous ICD for preventing sudden cardiac death in BrS patients without pacing indication (Arrhythmias Detection in a Real World Population [RHYTHM DETECT]; NCT02275637).