ABLATION FOR ATRIAL FIBRILLATION
Treatment of atrial fibrillation by silencing electrical activity in the posterior inter-pulmonary-vein atrium
Department of Heart Disease, Haukeland University Hospital, Institute of Medicine, University of Bergen, N-5021 Bergen, Norway
Aims: The recurrence of atrial fibrillation (AF) after pulmonary vein (PV) isolation is still a challenge. We investigated a new approach to treating AF patients by silencing electrical activity in the posterior inter-pulmonary-vein atrium (PIA).
Methods and results: Three ablation steps are required to obtain PIA electrical silence: electrical PV isolation, the creation of two lines of lesions between the two superior and inferior PVs and the abolition of residual electrical signals within the PIA. The endpoint was the electrical silence and the inability to pace in the PIA. The posterior inter-pulmonary-vein atrium silence was obtained in 42 AF patients (56 ± 9 years, four women). Recurrence of AF and atrial flutter was observed in 14 (33.3%) patients after the first procedure. Freedom from atrial arrhythmias after the second procedure was displayed by 94.4, 85.7, and 60.0% of patients with paroxysmal, persistent, and permanent AF, respectively. The left atrium (LA) volume was larger, and the percentages of the silent area of the LA surface and voltages were lower in patients with AF recurrence than in recurrence-free patients.
Conclusion: Posterior inter-pulmonary-vein atrium electrical silence can greatly decrease the AF recurrence. The clinical AF recurrence may be related to an enlarged LA, a low percentage of electrically silent area, and low voltage in the LA.
Key Words: Atrial fibrillation, Pulmonary vein, Left atrium, Ablation, Follow-up
* Corresponding author. Tel: +47 55 972220; fax: +47 55 975150. E-mail address: jian.chen{at}med.uib.no
Manuscript submitted 25 October 2007. Accepted after revision 19 January 2008.