Abstract
INTRODUCTION: between 20-30% of patients with Brugada syndrome (BrS) are carriers of deleterious genetic variants in the SCN5A gene. However, the risk factors for cardiac events in these patients remain under consideration, especially in the paediatric population, with many risk factors being still undetermined. OBJECTIVES: to investigate and evaluate individual clinical risk factors associated with cardiac events in children with BrS-SCN5A. METHODS: a Spanish retrospective single-centre paediatric cohort study was conducted including 41 BrS patients under 21 years of age carrying rare variants in the SCN5A gene. Demographic, clinical, genetic, and therapeutic variables were collected. Descriptive and univariate analyses were performed to identify independent risk factors for cardiac events. Outcomes were defined as cardiac syncope, ventricular tachycardia/fibrillation (VT/VF), sudden cardiac death (SCD), and appropriate shock in ICD. RESULTS: Nearly 20% of BrS-SCN5A patients presented with cardiac events. Five patients showing cardiogenic syncope, 4-SCD, 3-VT and 2 appropriate shocks in the ICD. The presence of bradycardia and bradyarrhythmia in baseline EKG (P<0.05), AV block type 1 (P<0.02), type 1 Brugada pattern in fever EKG (P<0.02), atrial fibrillation(P<0.05), arrhythmias in febrile episodes (P<0.05), progressive cardiac conduction defect (PCCD; P<0.001), sick sinus syndrome (SSS; P=0.001) and overlap phenotype (P<0.001) were predictor of cardiac events in this cohort. CONCLUSIONS: We have identified several statistically significant independent risk factors associated with cardiac events and worse phenotype severity in BrS-SCN5A children from a single-centre Spanish cohort. These results may help to improve prognosis assessment, establish accurate risk stratification, and prevent SCD in children with BrS-SCN5A. Future studies in large cohorts of different ethnicities are crucial to strengthen our risk factors in paediatric cohorts at high risk of malignant arrhythmias.