title: Relationship among complex signals, short cycle length activity, and dominant frequency in patients with long-lasting persistent AF: a high-density epicardial mapping study in humans.
abstract: BACKGROUND
  Complex fractionated atrial electrograms (CFAEs) and regions of high dominant frequency (DF) both may identify sites critical to the maintenance of atrial fibrillation (AF). CFAEs may be defined by either (1) complex multicomponent electrograms (EGMs) and/or continuous electrical activity (multicomponent/continuous EGM) or (2) discrete high-frequency EGMs.
  
  
  OBJECTIVE
  The purpose of this study was to test if the 2 definitions of CFAE identify the same arrhythmia substrate and determine the relationship of CFAE to areas of high DF.
  
  
  METHODS
  High-density epicardial mapping of the posterior left atrium was performed in 10 patients with long-lasting persistent AF. Point-by-point analysis was performed to determine the spatial distribution and correlation of CFAE defined as either (1) multicomponent/continuous-EGMs or (2) AF cycle length <120 ms. Additionally, spatial analysis was performed to determine the relationship of high DF sites to CFAE sites defined by each of the 2 definitions.
  
  
  RESULTS
  The percentage of sites deemed CFAE varied markedly between patients and was different depending on the definition of CFAE adopted. There was a poor correlation between CFAE defined by multicomponent/continuous EGMs and AF cycle length <120 ms (r = 0.18). High DF sites were arranged in clusters evenly distributed throughout the posterior left atrium, with 4.2 ± 1.0 high DF clusters per patient. Although there was poor point-by-point correlation between multicomponent/continuous EGMs and high DF sites (r = 0.107), spatial analysis revealed that 96% of multicomponent/continuous EGMs were found adjacent to and partially surrounding (≤5 mm) high DF sites.
  
  
  CONCLUSIONS
  There is poor anatomic overlap between CFAE defined by multicomponent/continuous EGMs and CFAE defined by AF cycle length <120 ms. Multicomponent/continuous EGMs are found adjacent to and surrounding sites of high DF. Further studies are needed to determine the mechanisms responsible for these different signals.
authors.affiliation: Department of Cardiology, Royal Melbourne Hospital and Department of Medicine, University of Melbourne, Melbourne, Australia.
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Lee
authors.forename: Kurt
authors.initials: K
authors.lastname: Roberts-Thomson
authors.forename: Andrew
authors.initials: A
authors.lastname: Madry
authors.forename: Steven
authors.initials: S
authors.lastname: Spence
authors.forename: Andrew
authors.initials: A
authors.lastname: Teh
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Heck
authors.forename: Saurabh
authors.initials: S
authors.lastname: Kumar
authors.forename: Peter M
authors.initials: PM
authors.lastname: Kistler
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Morton
authors.forename: Prashanthan
authors.initials: P
authors.lastname: Sanders
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Kalman
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000503:physiopathology* / Q000601:surgery; D017115:Catheter Ablation; D003936:Diagnosis, Computer-Assisted; D056149:Epicardial Mapping / Q000379:methods*; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results