title: [Focal atrial fibrillation. Clinical characteristic and results of radiofrequency ablation].
abstract: 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.
authors.affiliation: 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
authors.forename: René
authors.initials: R
authors.lastname: Asenjo
authors.forename: Raimundo
authors.initials: R
authors.lastname: Morris
authors.forename: Rodulfo
authors.initials: R
authors.lastname: Oyarzún
authors.forename: Gastón
authors.initials: G
authors.lastname: Dussaillant
authors.forename: Mario
authors.initials: M
authors.lastname: Ortiz
authors.forename: Martín
authors.initials: M
authors.lastname: Nicola
authors.forename: Eduardo
authors.initials: E
authors.lastname: Tapia
authors.forename: Marisol
authors.initials: M
authors.lastname: Valencia
authors.forename: Marjorie
authors.initials: M
authors.lastname: Sandoval
authors.forename: Patricia
authors.initials: P
authors.lastname: Morales
authors.forename: Viviana
authors.initials: V
authors.lastname: Avalos
authors.forename: Blanca
authors.initials: B
authors.lastname: Pezoa
authors.forename: Leonardo
authors.initials: L
authors.lastname: Von Krestschmann
authors.forename: Alejandro
authors.initials: A
authors.lastname: Abufhele
authors.forename: Miguel
authors.initials: M
authors.lastname: Oyonarte
mesh_terms: 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