Epidemiology, clinical characteristics and life-threatening risk profile of WPW in children: a single-center experience in South Wales for 30 years.

This study aims to assess the epidemiology, clinical presentation, management, and outcomes of pediatric Wolff-Parkinson-White (WPW) syndrome, as well as the incidence of life-threatening events (LTE) in South Wales. Retrospective review of patients (< 17 years old) diagnosed with WPW syndrome between 1986 and 2019 in South Wales. The study population consisted of 160 patients, of whom 86 (54%) were male. The prevalence of WPW syndrome was 0.028%. Thirty percent of cases were diagnosed during infancy, while 63% presented after age five. Incidental diagnosis occurred in 47 (29,3%) asymptomatic patients. Spontaneous resolution of delta wave in the entire cohort was observed in 19 patients (12%) while this phenomenon had occurred in 43% of neonates. Thirteen children [8.1% (13/160), 11 males] presented with serious arrhythmia giving an estimated risk of 3.8 per 1000 person-years during childhood in South Wales. Acute management was required in 36% (55/154) of patients, with seven (4.5%) experiencing pre-excited atrial fibrillation giving an estimated risk of 2 events per 1000 person-years. Among children with pre-excited atrial fibrillation and rapid ventricular conduction, only three out of seven children experienced aborted sudden cardiac death (1.9%) with an estimated life-threatening event risk of 1.7 per 1000 person-years. No deaths directly attributable to isolated WPW and related arrhythmia were recorded.Conclusions: Asymptomatic WPW in children demonstrated a high propensity for life-threatening events in South Wales, prompting a policy shift towards earlier referral for electrophysiology study (EPS) before adolescence. These findings underscore the need for more rigorous risk stratification and closer follow-up of all WPW patients, as asymptomatic cases do not guarantee safety. What's new? •What is already known on this topic - Historically, asymptomatic patients with WPW and those demonstrating loss of preexcitation on exercise tests were considered low risk for life-threatening events (LTE) and managed conservatively by non-electrophysiologist. •What this study adds - This study reinforces the observation of a higher incidence of life-threatening events in asymptomatic children with atrial fibrillation and neonates with atrial flutter in the context of WPW and advocates for a more cautious approach, suggesting a lower threshold for referring younger and asymptomatic children for RF ablation procedures before adolescence. •How this study might affect research, practice, policy - The findings of this national study underscore the necessity for closer monitoring of infants and children with WPW syndrome, irrespective of age and symptoms. EPS emerges as the primary method for identifying individuals at high risk of LTEs during childhood.