title: Comparison of Left Atrial Voltage between Sinus Rhythm and Atrial Fibrillation in Association with Electrogram Waveform.
abstract: BACKGROUND
  The efficacy of low-voltage-guided ablation in addition to pulmonary vein (PV) isolation for atrial fibrillation (AF) has been reported with voltage mapping being performed during sinus rhythm (SR) or AF. The study aimed to compare the left atrial voltage between SR and AF in association with the electrogram waveform.
  
  
  METHODS
  This prospective observational study included 30 consecutive patients with persistent AF. After completion of PV isolation, electrogram points were taken during both SR and AF at the identical locations evenly throughout the left atrium. Electrograms were divided into two types: normal (sharp electrogram with ≤3 peaks or duration <50 ms) and fractionated (>3 peaks and duration ≥50 ms).
  
  
  RESULTS
  During SR, 14 (47%) patients had low-voltage (0.5 mV) substrate with an area of 6.8 ± 4.5 cm2. In a total of 1,063 point pairs, 135 (13%) demonstrated a fractionated electrogram during SR and 483 (45%) during AF. The locations with fractionated electrograms during AF more frequently showed fractionation during SR compared to those with normal electrograms during AF (23% vs 5%, P < 0.0001), and had lower amplitude during SR (1.47 ± 1.29 mV vs 2.03 ± 1.19 mV, P < 0.0001). Electrogram amplitude was higher during SR than that during AF (1.77 ± 1.27 mV vs 0.96 ± 0.77 mV, P < 0.0001) with a weak correlation (r = 0.56, P < 0.0001). Subgroup analyses revealed that the correlation was relatively strong (r = 0.73, P < 0.0001) among the electrogram amplitudes with normal waveform during SR and AF.
  
  
  CONCLUSIONS
  Significant differences in electrogram voltage and fractionation degree may exist between SR and AF at the same locations in patients with persistent AF.
authors.affiliation: Cardiovascular Center, Kansai Rosai Hospital, Amagasaki, Hyogo, Japan.
authors.forename: Masaharu
authors.initials: M
authors.lastname: Masuda
authors.affiliation: Cardiovascular Center, Kansai Rosai Hospital, Amagasaki, Hyogo, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Fujita
authors.affiliation: Cardiovascular Center, Kansai Rosai Hospital, Amagasaki, Hyogo, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Iida
authors.affiliation: Cardiovascular Center, Kansai Rosai Hospital, Amagasaki, Hyogo, Japan.
authors.forename: Shin
authors.initials: S
authors.lastname: Okamoto
authors.affiliation: Cardiovascular Center, Kansai Rosai Hospital, Amagasaki, Hyogo, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Ishihara
authors.affiliation: Cardiovascular Center, Kansai Rosai Hospital, Amagasaki, Hyogo, Japan.
authors.forename: Kiyonori
authors.initials: K
authors.lastname: Nanto
authors.affiliation: Cardiovascular Center, Kansai Rosai Hospital, Amagasaki, Hyogo, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kanda
authors.affiliation: Cardiovascular Center, Kansai Rosai Hospital, Amagasaki, Hyogo, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Sunaga
authors.affiliation: Cardiovascular Center, Kansai Rosai Hospital, Amagasaki, Hyogo, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Tsujimura
authors.affiliation: Cardiovascular Center, Kansai Rosai Hospital, Amagasaki, Hyogo, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Matsuda
authors.affiliation: Cardiovascular Center, Kansai Rosai Hospital, Amagasaki, Hyogo, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Ohashi
authors.affiliation: Cardiovascular Center, Kansai Rosai Hospital, Amagasaki, Hyogo, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Uematsu
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000503:physiopathology* / Q000601:surgery*; D018780:Body Surface Potential Mapping / Q000379:methods*; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods*; D005260:Female; D006325:Heart Atria / Q000503:physiopathology* / Q000601:surgery; D006329:Heart Conduction System / Q000503:physiopathology* / Q000601:surgery; D006339:Heart Rate; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: amplitude; atrial fibrillation; low-voltage areas; sinus rhythm; voltage mapping