Bi-directional electrical pulmonary vein isolation as an endpoint for ablation of paroxysmal atrial fibrillation.
OBJECTIVE
Various approaches to pulmonary vein (PV) isolation have shown variable efficacy in patients with paroxysmal atrial fibrillation (AF). The purpose of this study is to report the efficacy and safety of routine isolation of all PVs using an endpoint of bi-directional electrical block.


METHODS
This study included 85 consecutive patients who underwent PV isolation for symptomatic paroxysmal AF. Complete isolation of all PVs was confirmed by demonstration of bi-directional block: (a) loss of all PV potentials, and (b) failure to capture the left atrium by pacing 10-14 bipolar pairs of electrodes on a circumferential catheter placed at the entrance of the PV at 10 mA with 2 ms pulse width. Induction of AF by burst pacing was attempted after PV isolation.


RESULTS
Freedom from symptomatic or asymptomatic AF (detected by event recorder or Holter monitor) was present in 85% and 76% of patients at 6 and 12 months. Additional mitral isthmus or posterior left atrial lines were performed in seven patients with inducible atrial arrhythmias after PV isolation. Atrial tachycardia occurred in three of these patients during long-term follow-up and in two of the 78 patients without additional ablation.


CONCLUSIONS
The use of bi-directional block circumferentially across all PV ostia as an electrophysiological endpoint may improve results of PV isolation for paroxysmal AF. Avoidance of routine additional left atrial ablation lines may decrease the risk of atrial tachycardia and esophageal fistula.
Essebag
Vidal
V
Harvard-Thorndike Electrophysiology Institute Cardiovascular Division, Beth Israel Deaconess Medical Center, Boston, MA, USA.
Wylie
John V
JV
Reynolds
Matthew R
MR
Baldessin
Ferdinando
F
McClennen
Seth
S
Shvilkin
Alexei
A
Germano
Joseph
J
Richardson
Allison
A
Zimetbaum
Peter J
PJ
Josephson
Mark E
ME
D000328:Adult; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins; D016896:Treatment Outcome
D000889:Anti-Arrhythmia Agents