title: The natural history of asymptomatic ventricular pre-excitation a long-term prospective follow-up study of 184 asymptomatic children.
abstract: OBJECTIVE
  The aim of this study was to describe the natural history of asymptomatic ventricular pre-excitation in children and to determine predictors of potentially life-threatening arrhythmic events.
  
  
  BACKGROUND
  Sudden death can be the first clinical manifestation in asymptomatic children with ventricular pre-excitation, but reduction of its incidence by prophylactic ablation requires the identification of subjects at high risk.
  
  
  METHODS
  Between 1995 and 2005 we prospectively collected clinical and electrophysiologic data from 184 children (66% male; median age 10 years; range 8 to 12 years) with asymptomatic ventricular pre-excitation on the electrocardiogram. After electrophysiologic testing, subjects were followed as outpatients taking no medications. The primary end point of the study was the occurrence of arrhythmic events. Predictors of potentially life-threatening arrhythmias were analyzed.
  
  
  RESULTS
  Over a median follow-up of 57 months (min/max 32/90 months) after electrophysiologic testing, 133 children (mean age 10 years; range 8 to 12 years) did not experience arrhythmic events, remaining totally asymptomatic, while 51 children had within 20 months (min/max 8/60 months) a first arrhythmic event, which was potentially life-threatening in 19 of them (mean age 10 years; range 10 to 14 years). Life-threatening tachyarrhythmias resulted in cardiac arrest (3 patients), syncope (3 patients), atypical symptoms (8 patients), or minimal symptoms (5 patients). Univariate analysis identified tachyarrhythmia inducibility (p < 0.001), anterograde refractory period of accessory pathways (APERP) </=240 ms (p < 0.001), and multiple accessory pathways (p < 0.001) as risk factors for potentially life-threatening arrhythmic events. Independent predictors by multivariate analysis were APERP (p = 0.001) and multiple accessory pathway (p = 0.001).
  
  
  CONCLUSIONS
  These findings are potentially relevant in terms of early identification of high-risk asymptomatic children with ventricular pre-excitation. Subjects with short APERPs and multiple pathways are at higher risk of developing life-threatening arrhythmic events and are the best candidates for prophylactic ablation.
authors.affiliation: Department of Electrophysiology, San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Santinelli
authors.forename: Andrea
authors.initials: A
authors.lastname: Radinovic
authors.forename: Francesco
authors.initials: F
authors.lastname: Manguso
authors.forename: Gabriele
authors.initials: G
authors.lastname: Vicedomini
authors.forename: Simone
authors.initials: S
authors.lastname: Gulletta
authors.forename: Gabriele
authors.initials: G
authors.lastname: Paglino
authors.forename: Patrizio
authors.initials: P
authors.lastname: Mazzone
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Ciconte
authors.forename: Stefania
authors.initials: S
authors.lastname: Sacchi
authors.forename: Simone
authors.initials: S
authors.lastname: Sala
authors.forename: Carlo
authors.initials: C
authors.lastname: Pappone
mesh_terms: D000367:Age Factors; D002648:Child; D015331:Cohort Studies; D016638:Critical Illness; D018450:Disease Progression; D004562:Electrocardiography; D015716:Electrocardiography, Ambulatory; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D005500:Follow-Up Studies; D006323:Heart Arrest / Q000401:mortality*; D006801:Humans; D007558:Italy; D008297:Male; D011226:Pre-Excitation Syndromes / Q000150:complications / Q000175:diagnosis; D011336:Probability; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D012737:Sex Factors; D018709:Statistics, Nonparametric; D016019:Survival Analysis; D013610:Tachycardia / Q000209:etiology / Q000401:mortality / Q000503:physiopathology; D013997:Time Factors; D014693:Ventricular Fibrillation / Q000209:etiology* / Q000401:mortality / Q000503:physiopathology; D054141:Ventricular Flutter / Q000209:etiology* / Q000401:mortality / Q000503:physiopathology; D014927:Wolff-Parkinson-White Syndrome / Q000150:complications / Q000175:diagnosis*