title: Effect of adenosine triphosphate on left atrial electrogram interval and dominant frequency in human atrial fibrillation.
abstract: BACKGROUND
  Complex fractionated atrial electrograms (CFAEs) and high dominant frequency (DF) are targets for atrial fibrillation (AF) ablation. Although adenosine triphosphate (ATP) is known to promote AF by shortening the atrial refractory period, its role in the pathogenesis of CFAEs and DF during AF is not fully understood.
  
  
  METHODS
  We recorded electrical activity from a 64-electrode basket catheter placed in the left atrium (LA) of patients with paroxysmal AF (PAF, n=18) or persistent AF (PerAF, n=19) before ablation. Atrial electrogram fractionation intervals (FIs) and DFs were measured from bipolar electrograms of each adjacent electrode pair. Offline mean atrial FIs and DFs were obtained before bolus injection of 30 mg ATP. Peak effect was defined as an R-R interval >3 s.
  
  
  RESULTS
  With ATP, the mean FI decreased (from 110.4±29.1 ms to 90.5±24.7 ms, P<0.0001) and DF increased (from 6.4±0.6 Hz to 7.1±0.8 Hz, P<0.0001) in all patients. There was no difference in the FI decrease between the two groups (-20.3±20.5 ms vs. -19.6±14.5 ms, P=0.6032), but the increase in DF was significantly greater in PAF patients (1.1±0.8 Hz vs. 0.3±0.6 Hz, P=0.0051).
  
  
  CONCLUSIONS
  ATP shortens atrial FIs and increases DFs in both PAF and PerAF patients. The significant increase in DF in PAF patients suggests that pathophysiologic characteristics related to the frequency of atrial fractionation change as atrial remodeling progresses.
authors.affiliation: Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Rikitake
authors.initials: R
authors.lastname: Kogawa
authors.affiliation: Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Okumura
authors.affiliation: Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Watanabe
authors.affiliation: Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kofune
authors.affiliation: Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Nagashima
authors.affiliation: Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Mano
authors.affiliation: Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Sonoda
authors.affiliation: Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Sasaki
authors.affiliation: Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Iso
authors.affiliation: Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Takahashi
authors.affiliation: Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Kimie
authors.initials: K
authors.lastname: Ohkubo
authors.affiliation: Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Toshiko
authors.initials: T
authors.lastname: Nakai
authors.affiliation: Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Hirayama
keywords: Atrial fibrillation; Basket catheter; Complex fractionated atrial electrogram; Dominant frequency