Electrophysiological and electrocardiographic characteristics of focal atrial tachycardia originating from the pulmonary veins - Acute and long-term outcomes of radiofrequency ablation

Background - The objective of this study was to describe the electrophysiological characteristics, anatomic distribution, and long-term outcome after focal ablation (RFA) of pulmonary vein (PV) atrial tachycardia (AT). Both atrial fibrillation (AF) and AT may be due to a rapidly firing focus in the PVs. Whether these represent two aspects of the same process is unknown. Methods and Results - Twenty- seven patients with 28 PV(16%) ATs of a consecutive series of 172 undergoing RFA for focal AT are reported. The mean age was 39 +/- 16 years, with symptoms for 9 +/- 14 years resistant to 1.7 +/- 0.8 medications. AT occurred spontaneously or with isoproterenol in all patients and was not inducible with PES in any. The distribution of PV ATs was right superior PV, 11; left superior PV, 11; left inferior PV, 5; and right inferior PV, 1; 26of 28 foci (93%) were ostial. RFA was successful in 28 of 28 PV ATs acutely. RFA was focal in 25 of 28, with PV isolation of a single target vein in 3. There were 4 recurrences at a mean of 3.3 months. Repeat RFA was performed in all 4 and successful in 3 of 4. All but one recurrence occurred from the same site. Long-term success was achieved in 26 of 27 (96%) patients at mean follow-up of 25 +/- 22 months. No patients have had subsequent development of AF or AT from a different site. Conclusions - PV AT has a distribution similar to PV AF, with a propensity to upper veins. However, the majority of foci are ostial, and only a small percentage occur from deep in the PV. Focal RFA is associated with high long-term success, with freedom from both AT from other sites and from AF. PV AT is a localized process and therefore may be different from PV AF.