title: Mapping and ablation of ventricular fibrillation associated with long-QT and Brugada syndromes.
abstract: BACKGROUND
  The long-QT and Brugada syndromes are important substrates of malignant ventricular arrhythmia. The feasibility of mapping and ablation of ventricular arrhythmias in these conditions has not been reported.
  
  
  RESULTS
  Seven patients (4 men; age, 38+/-7 years; 4 with long-QT and 3 with Brugada syndrome) with episodes of ventricular fibrillation or polymorphic ventricular tachycardia and frequent isolated or repetitive premature beats were studied. These premature beats were observed to trigger ventricular arrhythmias and were localized by mapping the earliest endocardial activity. In 4 patients, premature beats originated from the peripheral right (1 Brugada) or left (3 long-QT) Purkinje conducting system and were associated with variable Purkinje-to-muscle conduction times (30 to 110 ms). In the remaining 3 patients, premature beats originated from the right ventricular outflow tract, being 25 to 40 ms ahead of the QRS. The accuracy of mapping was confirmed by acute elimination of premature beats after 12+/-6 minutes of radiofrequency applications. During a follow-up of 17+/-17 months using ambulatory monitoring and defibrillator memory interrogation, no patients had recurrence of symptomatic ventricular arrhythmia but 1 had persistent premature beats.
  
  
  CONCLUSIONS
  Triggers from the Purkinje arborization or the right ventricular outflow tract have a crucial role in initiating ventricular fibrillation associated with the long-QT and Brugada syndromes. These can be eliminated by focal radiofrequency ablation.
authors.affiliation: Hôpital Cardiologique du Haut-Lévêque, Avenue de Magellan, 33604 Bordeaux-Pessac, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Haïssaguerre
authors.forename: Fabrice
authors.initials: F
authors.lastname: Extramiana
authors.forename: Mélèze
authors.initials: M
authors.lastname: Hocini
authors.forename: Bruno
authors.initials: B
authors.lastname: Cauchemez
authors.forename: Pierre
authors.initials: P
authors.lastname: Jaïs
authors.forename: Jose Angel
authors.initials: JA
authors.lastname: Cabrera
authors.forename: Jerónimo
authors.initials: J
authors.lastname: Farré
authors.forename: Gerónimo
authors.initials: G
authors.lastname: Farre
authors.forename: Antoine
authors.initials: A
authors.lastname: Leenhardt
authors.forename: Prashanthan
authors.initials: P
authors.lastname: Sanders
authors.forename: Christophe
authors.initials: C
authors.lastname: Scavée
authors.forename: Li-Fern
authors.initials: LF
authors.lastname: Hsu
authors.forename: Rukshen
authors.initials: R
authors.lastname: Weerasooriya
authors.forename: Dipen C
authors.initials: DC
authors.lastname: Shah
authors.forename: Robert
authors.initials: R
authors.lastname: Frank
authors.forename: Philippe
authors.initials: P
authors.lastname: Maury
authors.forename: Marc
authors.initials: M
authors.lastname: Delay
authors.forename: Stéphane
authors.initials: S
authors.lastname: Garrigue
authors.forename: Jacques
authors.initials: J
authors.lastname: Clémenty
mesh_terms: D000328:Adult; D001145:Arrhythmias, Cardiac / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D018780:Body Surface Potential Mapping / Q000379:methods*; D017115:Catheter Ablation; D015716:Electrocardiography, Ambulatory; D022062:Electrophysiologic Techniques, Cardiac; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology; D006801:Humans; D008133:Long QT Syndrome / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D008297:Male; D013575:Syncope / Q000209:etiology; D013577:Syndrome; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery