title: Relationship between the spectral characteristics of atrial fibrillation and atrial tachycardias that occur after catheter ablation of atrial fibrillation.
abstract: BACKGROUND
  During catheter ablation of complex fractionated atrial electrograms, persistent atrial fibrillation (AF) may convert to an atrial tachycardia (AT).
  
  
  OBJECTIVE
  The purpose of this study was to investigate the possible mechanisms of AT by examining the spectral and electrophysiologic characteristics of AF and ATs that occur after catheter ablation of AF.
  
  
  METHODS
  The subjects of this study were 33 consecutive patients with persistent AF who had conversion of AF to AT during ablation of AF (group I) and 20 consecutive patients who underwent ablation of persistent AT that developed more than 1 month after AF ablation (group II). Spectral analysis of the coronary sinus (CS) electrograms and lead V(1) was performed during AF at baseline, before conversion, and during AT. The spatial relationship between the AT mechanism and ablation sites was examined.
  
  
  RESULTS
  A spectral component with a frequency that matched the frequency of AT was present in the baseline periodogram of AF more often in group I (52%) than in group II (20%, P = .02). Ablation resulted in a decrease in the dominant frequency of AF but not in the frequency of the spectral component that matched the AT. There was a significant direct relationship between the baseline dominant frequency of AF and the frequency of AT in the CS in group I (r = 0.76, P <.0001) but not in group II (r = 0.38, P = .09). ATs were macroreentrant in 64% and 60% of patients in groups I and II, respectively (P = .8). The AT site was more likely to be distant (>1 cm) from AF ablation sites in group I (70%) than in group II (35%, P = .007).
  
  
  CONCLUSIONS
  The findings of this study suggest that ATs observed during ablation of AF often may be drivers of AF that become manifest after elimination of higher-frequency sources and fibrillatory conduction.
authors.affiliation: Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan, USA.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Yoshida
authors.forename: Aman
authors.initials: A
authors.lastname: Chugh
authors.forename: Magnus
authors.initials: M
authors.lastname: Ulfarsson
authors.forename: Eric
authors.initials: E
authors.lastname: Good
authors.forename: Michael
authors.initials: M
authors.lastname: Kuhne
authors.forename: Thomas
authors.initials: T
authors.lastname: Crawford
authors.forename: Jean F
authors.initials: JF
authors.lastname: Sarrazin
authors.forename: Nagib
authors.initials: N
authors.lastname: Chalfoun
authors.forename: Darryl
authors.initials: D
authors.lastname: Wells
authors.forename: Warangkna
authors.initials: W
authors.lastname: Boonyapisit
authors.forename: Srikar
authors.initials: S
authors.lastname: Veerareddy
authors.forename: Sreedhar
authors.initials: S
authors.lastname: Billakanty
authors.forename: Wai S
authors.initials: WS
authors.lastname: Wong
authors.forename: Krit
authors.initials: K
authors.lastname: Jongnarangsin
authors.forename: Frank
authors.initials: F
authors.lastname: Pelosi
authors.forename: Frank
authors.initials: F
authors.lastname: Bogun
authors.forename: Fred
authors.initials: F
authors.lastname: Morady
authors.forename: Hakan
authors.initials: H
authors.lastname: Oral
mesh_terms: D001281:Atrial Fibrillation / Q000503:physiopathology / Q000601:surgery*; D018780:Body Surface Potential Mapping / Q000379:methods; D017115:Catheter Ablation / Q000009:adverse effects* / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods; D011379:Prognosis; D012815:Signal Processing, Computer-Assisted; D013612:Tachycardia, Ectopic Atrial / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology