title: Percutaneous catheter ablation of arrhythmias in children.
abstract: BACKGROUND
  Supraventricular tachycardias (SVTs) are the most common arrhythmias in children, with Wolff-Parkinson-White (WPW) syndrome the most prevalent entity. Percutaneous catheter ablation is now the standard of care for SVT in pediatric patients, although specific techniques are required due to their age.
  
  
  OBJECTIVE
  To evaluate the results of percutaneous catheter ablation of arrhythmias in children at our institution.
  
  
  METHODS
  This was a retrospective study of the clinical records of patients aged 18 years who underwent electrophysiologic study and ablation between January 2002 and December 2006. The following variables were evaluated: demographic data, type of arrhythmia, associated structural heart disease, type of energy used, immediate and late success rate and incidence of complications.
  
  
  RESULTS
  During this period, 101 procedures were performed in 97 patients aged < or = 18 years. The mean age of the patients was 15.9 +/- 2.5 years (range: 7.7-18 years), and fifty-five (56.7%) were male. The arrhythmias treated were, in decreasing order of frequency: WPW syndrome (58.4%), atrioventricular reentrant tachycardia (25.7%), atrial tachycardia (5.9%), right ventricular outflow tract (RVOT) tachycardia (5%), ventricular tachycardia (2%), atrial fibrillation (2%) and frequent extrasystoles originating in the left atrium (1%). There was associated structural heart disease in six patients. Cryoablation was performed in four cases (parahisian accessory pathways in three and anterolateral accessory pathway in one). The immediate success rate was 94.1%. The six unsuccessful cases corresponded to five with parahisian accessory pathways (the procedure was not completed due to very high risk of inducing complete atrioventricular block [AVB]) and one case of RVOT tachycardia associated with arrhythmogenic right ventricular dysplasia. There were complications in two procedures (2%): one case of right bundle branch block and one of ventricular tachycardia requiring electrical cardioversion. The mean follow-up was 17.6 months. In 87.1% of cases there was clinical and ECG success on long-term followup. Three patients (3%) required repeat procedures, and were asymptomatic in later follow-up.
  
  
  CONCLUSIONS
  Percutaneous catheter ablation of arrhythmias in children proved to be a safe and effective treatment.
authors.affiliation: Serviço de Cardiologia, Hospital de São Bernardo, Centro Hospitalar de Setúbal, Setúbal, Portugal. filipeseixo@spc.pt
authors.forename: Filipe
authors.initials: F
authors.lastname: Seixo
authors.forename: Renata
authors.initials: R
authors.lastname: Rossi
authors.forename: Pedro
authors.initials: P
authors.lastname: Adração
authors.forename: Diogo
authors.initials: D
authors.lastname: Cavaco
authors.forename: Katya Reis
authors.initials: KR
authors.lastname: Santos
authors.forename: Francisco Bello
authors.initials: FB
authors.lastname: Morgado
authors.forename: Fernando Maymone
authors.initials: FM
authors.lastname: Martins
mesh_terms: D000293:Adolescent; D000556:Ambulatory Surgical Procedures; D001145:Arrhythmias, Cardiac / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D014927:Wolff-Parkinson-White Syndrome / Q000601:surgery