Epidemiology of paediatric inherited arrhythmogenic diseases under "Real World" conditions: findings from a 10-year longitudinal study in Eastern Austria.

Inherited arrhythmogenic diseases (IADs), such as long QT syndrome (LQTS), Brugada syndrome (BrS), arrhythmogenic right ventricular cardiomyopathy (ARVC), catecholaminergic polymorphic ventricular tachycardia (CPVT) and laminopathies (LP), are rare conditions in which arrhythmogenic sudden cardiac death (SCD) may occur as the first symptom. We analysed paediatric prevalence data obtained under "Real World" conditions, defined as a diagnosis based on clinical symptoms, family history or incidentally written ECGs without screening or registry programmes. Findings were compared to published data. This single centre cross-sectional study was performed over a 10-year period in Eastern Austria. We collected all patients with genetically and/or clinically diagnosed IADs (LQTS, SQT, BrS, CPVT, ARVC and laminopathies) and determined the prevalence and paths to diagnosis for each IAD. At the most recent reference date (2024/12/31), 112 patients were enrolled, corresponding to a paediatric prevalence of 1:7000 of all IADs. Subgroup analysis revealed a prevalence of 1:13,000 for LQTS, 1:22,000 for BrS, 1:43,000 for ARVC and 1:368,000 for CVPT. Most patients with LQTS (62%) were diagnosed after incidental ECG, whereas BrS (79%) and ARVC (64%) were diagnosed mainly by family screening.

conclusionThis first study on the prevalence of paediatric IADs obtained under "Real World" conditions at a tertiary care centre, reports significantly lower numbers compared to published data. Our findings on patients' paths to diagnosis suggest that LQTS patients may benefit from selected age-dependent screening programmes, whereas for BrS and ARVC, family screening and intensive collaboration with adult care providers are crucial for diagnosis. WHAT IS KNOWN: • Although hereditary primary electrical disorders are rare diseases, they may account for 30% or more of all sudden cardiac deaths in the young, making early detection in the general paediatric population crucial. WHAT IS NEW: • This is the first study on population-based paediatric prevalence of primary electrical disorders using "Real World" data. • The significant lower numbers demand a change in patient acquisition including screening programmes, registries and intensive intergenerational care of families by close cooperation between paediatric and adult cardiologists.