[Focal atrial fibrillation. Clinical characteristic and results of radiofrequency ablation].
BACKGROUND
Atrial fibrillation can originate in arrhythmogenic foci coming from the pulmonary veins. Patients with atrial fibrillation, initiated from triggering foci, can be treated with radiofrequency ablation.


OBJECTIVE
To report the results of radiofrequency ablation in patients with focal atrial fibrillation.


METHODS
Thirteen patients with focal atrial fibrillation (8 male, aged 19 to 60 years old) are reported. Twelve had frequent crises refractory to antiarrhythmic drugs. Two had also flutter and tachycardia. One had a permanent atrial fibrillation lasting five years. Two had ventricular dysfunction and left atrial dilatation. The triggering focus was identified during the electrophysiological study, by the precocity of the potential that initiated the atrial fibrillation.


RESULTS
All patients had early atrial extrasystolic beats, isolated or repetitives, that preceded atrial fibrillation. During the electrophysiological study, 18 foci (3 in the right and 15 in the left atrium all in pulmonary veins) were identified. Radiofrequency ablation had immediate success in 11 patients. In 5, a flutter was also ablated. One patient had a sinus dysfunction after the procedure and atrial fibrillation was not eliminated. In this and other patient in whom the procedure failed, a pacemaker was implanted and the atrioventricular node was blocked. In a follow up, ranging from 4 to 31 months, eight patients are asymptomatic and 3 recidivated. No complications have been detected.


CONCLUSIONS
Patients with focal atrial fibrillation have common clinical and electrocardiographic features. Radiofrequency ablation of the triggering focus is possible and effective in most cases.
Asenjo
René
R
Centro Nacional de Arritmias, Centro Cardiovascular, Facultad de Medicina, Hospital Clínico Universidad de Chile, Laboratorio de Electrofisiología, Clínica Alemana, Santiago de Chile. reneasenjo@vtr.net
Morris
Raimundo
R
Oyarzún
Rodulfo
R
Dussaillant
Gastón
G
Ortiz
Mario
M
Nicola
Martín
M
Tapia
Eduardo
E
Valencia
Marisol
M
Sandoval
Marjorie
M
Morales
Patricia
P
Avalos
Viviana
V
Pezoa
Blanca
B
Von Krestschmann
Leonardo
L
Abufhele
Alejandro
A
Oyonarte
Miguel
M
D000328:Adult; D001281:Atrial Fibrillation / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000503:physiopathology; D016896:Treatment Outcome