title: Catheter ablation of junctional ectopic tachycardia in children, with preservation of atrioventricular conduction.
abstract: BACKGROUND
  Idiopathic junctional ectopic tachycardia is a rare arrhythmia in children. Several studies have demonstrated that drug therapy is often ineffective and sometimes the only achieved effect is rate control. Early presentation and frequent recurrence are associated with adverse outcome.
  
  
  METHODS
  Three consecutive children, aged 9, 7 and 12 years respectively, underwent radiofrequency catheter ablation for junctional ectopic tachycardia, after having failed antiarrhythmic drug therapy. The entire His bundle was plotted out and marked, using the Localisa navigation system. The arrhythmia was readily and repeatedly inducible using intravenous isoprenaline infusion and the site of earliest retrograde conduction during tachycardia could be assessed. Ablations were performed in sinus rhythm, empirically targeting the site of earliest retrograde conduction during tachycardia.
  
  
  RESULTS
  This approach was successful in abolishing tachyarrhythmia in the first two patients, in whom the successful ablation site was located superoparaseptally. In the third patient, junctional ectopic tachycardia was inducible, despite abolishing retrograde atrial activation, in a septal location on the tricuspid valve annulus. Further ablations in the superoparaseptal region, closer to the His bundle, were successful in rendering tachyarrhythmia noninducible. Over a median follow-up of 10 months, none of the patients has had recurrence of arrhythmia, despite discontinuing all antiarrhythmic medications.
  
  
  CONCLUSIONS
  Radio frequency catheter ablation of junctional ectopic tachycardia is feasible with preservation of atrioventricular conduction.
authors.affiliation: Department of Paediatric Cardiology, University Hospital of Cologne, Joseph-Stelzmann-Strasse 9, 50924 Cologne, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Emmel
authors.forename: N
authors.initials: N
authors.lastname: Sreeram
authors.forename: K
authors.initials: K
authors.lastname: Brockmeier
mesh_terms: D001283:Atrioventricular Node / Q000503:physiopathology*; D017115:Catheter Ablation / Q000379:methods*; D002648:Child; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D020127:Recovery of Function; D013613:Tachycardia, Ectopic Junctional / Q000175:diagnosis* / Q000601:surgery*; D016896:Treatment Outcome