title: Discrimination of thoracic vein potentials facilitated by atrial pacing during the isolation.
abstract: BACKGROUND
  Although electrical thoracic vein (TV) isolation is an established strategy during atrial fibrillation (AF) ablation, discriminating TV potentials from far-field signals is critical for the achievement.
  
  
  RESULTS
  One hundred consecutive drug-refractory symptomatic paroxysmal AF patients who underwent AF catheter ablation were included. All patients underwent circumferential pulmonary vein (PV) isolation during distal coronary sinus (CS) pacing with a cycle length of 600 ms. A superior vena cava (SVC) isolation was added during high right atrial (HRA) pacing with the same cycle length in 79 patients in whom SVC potentials were identified. The interval between the near-field PV potentials and far-field atrial signals significantly prolonged more during distal CS pacing than sinus rhythm (SR) in the left superior (26.0 [18.5-32.8] ms to 36.0 [24.3-55.5] ms, P < 0.01) and left inferior PVs (21.0 [14.0-30.0] ms to 40.0 [23.0-56.0] ms, P < 0.01), but not in the right superior (34.0 [20.0-40.0] ms to 23.0 [18.0-36.0] ms, P = 0.13) and right inferior PVs (22.0 [16.0-28.0] ms to 25.0 [18.0-38.0] ms, P = 0.05). The interval between the SVC potentials and far-field atrial signals significantly prolonged more during HRA pacing than SR (20.0 [0-32.0] ms to 34.0 [24.0-46.0] ms, P < 0.01). Electrical isolation was successfully achieved in all TVs without any complications except for transient right phrenic nerve palsy in two patients.
  
  
  CONCLUSIONS
  Discrimination of ipsilateral left PVs and SVC potentials is facilitated by pacing from the distal CS and HRA, respectively. Better recognition of TV potentials would help to achieve electrical isolation.
authors.affiliation: Cardiology Division, Cardiovascular Center, Tsuchiura Kyodo Hospital, Tsuchiura, Ibaraki, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Masuda
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Miyazaki
authors.forename: Shigeki
authors.initials: S
authors.lastname: Kusa
authors.forename: Yuki
authors.initials: Y
authors.lastname: Komatsu
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Hachiya
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Iesaka
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000601:surgery*; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods; D005260:Female; D006329:Heart Conduction System / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013909:Thorax / Q000098:blood supply; D016896:Treatment Outcome; D014683:Vena Cava, Superior / Q000601:surgery*
keywords: atrial fibrillation; far-field potential; isolation; thoracic vein