Mapping and ablation of ventricular fibrillation associated with long-QT and Brugada syndromes.
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.
Haïssaguerre
Michel
M
Hôpital Cardiologique du Haut-Lévêque, Avenue de Magellan, 33604 Bordeaux-Pessac, France.
Extramiana
Fabrice
F
Hocini
Mélèze
M
Cauchemez
Bruno
B
Jaïs
Pierre
P
Cabrera
Jose Angel
JA
Farré
Jerónimo
J
Farre
Gerónimo
G
Leenhardt
Antoine
A
Sanders
Prashanthan
P
Scavée
Christophe
C
Hsu
Li-Fern
LF
Weerasooriya
Rukshen
R
Shah
Dipen C
DC
Frank
Robert
R
Maury
Philippe
P
Delay
Marc
M
Garrigue
Stéphane
S
Clémenty
Jacques
J
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