Janson CM, Millenson ME, Okunowo O, et al. - In an unselected pediatric Wolff-Parkinson-White (WPW) population, ventricular fibrillation (VF) and life-threatening event (LTE) risk could be assessed using a large claims dataset and the observed range of 0.8-1.9 events per 1000 person-years was found to be consistent with previous reports from selected populations. The significant increase in VF and LTE risk in pediatric WPW was corroborated and quantified by the comparison of event rates to matched controls.

• This is a retrospective cohort study, utilizing claims data from the IBM MarketScan Research Databases, to determine LTE incidence in children with WPW (age 1-18 years) in a large contemporary representative population.

• Excluding congenital heart disease/cardiomyopathy, 6,946 patients were examined; WPW prevalence was 0.03% (8,733/26,684,581) over median observation of 1.6 years (IQR 0.7-2.9).

• Overall 49 participants suffered LTE, including VF in 20.

• VF incidence and LTE incidence was noted to be 0.8 events per 1000 person-years and 1.9 events per 1000 person-years, respectively.

• Controls did not develop VF; a 70 times greater rate of LTE was observed in WPW (0.7%) vs in controls (0.01%).