title: Atrioventricular junction ablation and pacemaker therapy in patients with drug-resistant atrial tachyarrhythmias after the Fontan operation.
abstract: BACKGROUND
  Drug-resistant intraatrial reentrant tachycardia (IART) occurs frequently after the Fontan operation and is a major cause of morbidity and rarely mortality. We describe our experience with AV junction ablation after pacemaker implantation in postoperative Fontan patients with drug-resistant IART.
  
  
  RESULTS
  We performed retrospective analysis of Fontan patients with IART and attempted radiofrequency ablation (RFA) of the AV junction. Seven patients (6 male) were identified, with a mean age at Fontan of 9.3 years (range 5.8-13.3) and a median age at RFA of 18 years (range 14.5-23.3). Mean follow-up prior to RFA was 764 +/- 235 days and after RFA 1,541 +/- 1,235 days. IART was refractory to antiarrhythmic drugs in all patients, and all had undergone pacemaker placement. Mean onset of IART was 44.1 months (range 0-142) after Fontan. Mean duration of atrial arrhythmia prior to RFA was 72 +/- 48 m (range 16-148). Ablation of the AV junction was successful or partially successful in all patients. Complete AV block occurred in 6 patients. Normal AV conduction was not seen during a mean follow-up of 1,541 days. The mean number of antiarrhythmic medications decreased from 2.8 +/- 1.5 to 0.7 +/- 0.8 (P <0.05).
  
  
  CONCLUSIONS
  In Fontan patients with drug-resistant IART, RFA of the AV junction with prior pacemaker implant is an effective therapeutic option. Despite the introduction of pacemaker dependence, this option should be considered in patients who did not respond to RFA of IART or who are at high operative risk for Fontan conversion.
authors.affiliation: Lillie Frank Abercrombie Section of Pediatric Cardiology, Texas Children's Hospital and Baylor College of Medicine, Houston, Texas 77030, USA.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Friedman
authors.forename: Joachim C
authors.initials: JC
authors.lastname: Will
authors.forename: Arnold L
authors.initials: AL
authors.lastname: Fenrich
authors.forename: Naomi J
authors.initials: NJ
authors.lastname: Kertesz
mesh_terms: D000293:Adolescent; D000328:Adult; D001281:Atrial Fibrillation / Q000209:etiology / Q000628:therapy*; D001283:Atrioventricular Node / Q000601:surgery*; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D017115:Catheter Ablation / Q000379:methods*; D003131:Combined Modality Therapy / Q000379:methods; D004351:Drug Resistance; D005260:Female; D018729:Fontan Procedure / Q000009:adverse effects*; D006801:Humans; D008297:Male; D010138:Pacemaker, Artificial; D011182:Postoperative Care / Q000379:methods*; D012189:Retrospective Studies; D013610:Tachycardia / Q000209:etiology / Q000628:therapy*; D016896:Treatment Outcome