title: Frequency analysis of the fibrillatory activity from surface ECG lead V1 and intracardiac recordings: implications for mapping of AF.
abstract: OBJECTIVE
  Fibrillatory waves observed in the surface electrograms may be a direct reflection of the electrophysiologic mechanism of the atrial fibrillation (AF). This study compared the fibrillatory waves in the surface ECG and the individual intracardiac mapping sites in different types of paroxysmal AF.
  
  
  RESULTS
  Thirty patients with paroxysmal AF originating from the pulmonary veins (PVs) or superior vena cava (SVC) were enrolled. Frequency analysis was performed on the intracardiac electrograms recorded from various mapping sites in both atria sequentially with simultaneous surface electrogram recordings. The SVC-AF patients had a trend toward a higher DF in ECG lead V1 when compared with the PV-AF patients (7.35 +/- 2.09 vs. 5.89 +/- 0.79 Hz, P = 0.018). The mean dominant frequency (DF) of the LA mapping sites in the PV-AF patients was higher than that in the SVC-AF patients (7.06 +/- 0.66 vs. 6.13 +/- 0.96 Hz, P = 0.009), whereas the mean DF of the RA mapping sites was similar between the two groups (5.84 +/- 0.80 vs. 6.26 +/- 1.11 Hz, P = NS). The intra-class correlation coefficient (ICC) between the mean DF of the RA sites and V1 was higher (r = 0.21, P = 0.02) when compared with the mean DF of the LA sites (r = -0.007, P > 0.05). Furthermore, the maximal ICC was observed in the anterolateral RA free wall (r = 0.84, P < 0.001) and not the other anatomic sites of the RA and LA.
  
  
  CONCLUSIONS
  The fibrillatory activity observed in ECG lead V1 correlated primarily with the activity of the anterolateral RA free wall and thus may be useful for detecting the AF source if it is close to that area.
authors.affiliation: Department of Medicine, Taiwan I-Lan Hospital, I-Lan, Taiwan, Republic of China.
authors.forename: Nei-Wei
authors.initials: NW
authors.lastname: Hsu
authors.forename: Yenn-Jiang
authors.initials: YJ
authors.lastname: Lin
authors.forename: Ching-Tai
authors.initials: CT
authors.lastname: Tai
authors.forename: Tsair
authors.initials: T
authors.lastname: Kao
authors.forename: Shih-Lin
authors.initials: SL
authors.lastname: Chang
authors.forename: Wanwarang
authors.initials: W
authors.lastname: Wongcharoen
authors.forename: Li-Wei
authors.initials: LW
authors.lastname: Lo
authors.forename: Ameya R
authors.initials: AR
authors.lastname: Udyavar
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Hu
authors.forename: Han-Wen
authors.initials: HW
authors.lastname: Tso
authors.forename: Yi-Jen
authors.initials: YJ
authors.lastname: Chen
authors.forename: Satoshi
authors.initials: S
authors.lastname: Higa
authors.forename: Shih-Ann
authors.initials: SA
authors.lastname: Chen
mesh_terms: D000328:Adult; D001281:Atrial Fibrillation / Q000503:physiopathology*; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006325:Heart Atria / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000503:physiopathology; D012815:Signal Processing, Computer-Assisted; D014683:Vena Cava, Superior / Q000503:physiopathology