Midterm Efficacy of SubcutAneous Implantable CardioVErter-Defibrillator in ≤ 18 Year-Old CHILDREN (SAVE CHILDREN-II...

The subcutaneous implantable cardioverter-defibrillator (S-ICD) avoids transvenous leads and is a promising option for sudden cardiac death (SCD) prevention in pediatric patients. However, mid-term outcomes and post-shock management strategies remain insufficiently characterized.

This multicenter, retrospective observational study included pediatric patients (≤ 18 years) who underwent S-ICD implantation between February 2016 and July 2021. Clinical characteristics, pre-implant screening, procedural details, device-related events, and follow-up data were analyzed. The incidence and management of appropriate and inappropriate therapies and subsequent recurrence were evaluated.

Ninety-six patients (median age 14.5 years) were enrolled and followed for a median of 70 months (29-75.0 months). Sensing vector suitability remained stable despite somatic growth. Appropriate shocks occurred in 32 patients (33.7%), while inappropriate shocks occurred in 27 (28.4%). After appropriate therapy, intensified pharmacological treatment and catheter ablation prevented recurrent device therapy in 45.5% and 50.0% of cases, respectively, although device shock occurred in 50.9% despite intervention. Following inappropriate therapy, device reprogramming and lifestyle guidance prevented recurrence in 71.4% of patients (15/21). Device-related infection was rare (2 cases), and no lead fractures were observed.

S-ICD therapy demonstrated favorable mid-term safety and efficacy in pediatric patients, with durable sensing performance and a low incidence of device-related infection. Although inappropriate shocks were not uncommon, appropriate post-shock management effectively reduced recurrence, supporting S-ICD as a viable option for selected pediatric patients without pacing requirements.