title: Prevalence, characteristics, mapping, and catheter ablation of potential rotors in nonparoxysmal atrial fibrillation.
abstract: BACKGROUND
  Identification of critical atrial substrates in patients with nonparoxysmal atrial fibrillation (AF) failing to respond to pulmonary vein isolation is important. This study investigated the signal characteristics, substrate nature, and ablation results of rotors during AF.
  
  
  RESULTS
  In total, 53 patients (age=55±8), 31 with persistent AF and 22 with long-lasting AF, underwent pulmonary vein isolation and substrate modification of complex fractionated atrial electrograms. Small-radius-reentrant rotors were identified from signal analyses of the dominant frequency and fractionation interval and nonlinear analyses (newly developed, beat-to-beat nonlinear measurement of the repetitiveness of the electrogram morphology>6 seconds). In 15% of the patients, activation maps demonstrated occurrences of rotor-like small-radius reentrant circuits (n=9; 1.1 per patient; cycle length=110±21 ms; diameter=11±6 mm) with fibrillation occurring outside these areas. Rotors were identified by conventional point-by-point mapping and signal analyses and were subsequently eradicated by catheter ablation in these patients. Persistent AF for <1 year, a smaller left atrial size, substrates with higher mean voltages and shorter total activation durations predicted a higher incidence of rotors (all P<0.05). In the multivariable model, areas of reentrant circuits exhibited a higher dominant frequency, kurtosis, and higher degree of a beat-to-beat electrogram similarity than areas without or outside the rotors (all P<0.05).
  
  
  CONCLUSIONS
  Rotor-like re-entry with fibrillatory conduction was found in a limited number of patients with nonparoxysmal AF after pulmonary vein isolation. Those areas were characterized by rapid repetitive activity with a high degree of electrogram similarity.
authors: Faculty of Medicine & Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.
authors: Yenn-Jiang
authors: YJ
authors: Lin
authors: Men-Tzung
authors: MT
authors: Lo
authors: Chen
authors: C
authors: Lin
authors: Shih-Lin
authors: SL
authors: Chang
authors: Li-Wei
authors: LW
authors: Lo
authors: Yu-Feng
authors: YF
authors: Hu
authors: Wan-Hsin
authors: WH
authors: Hsieh
authors: Hung-Yu
authors: HY
authors: Chang
authors: Wen-Yu
authors: WY
authors: Lin
authors: Fa-Po
authors: FP
authors: Chung
authors: Jo-Nan
authors: JN
authors: Liao
authors: Yun-Yu
authors: YY
authors: Chen
authors: Dicky
authors: D
authors: Hanafy
authors: Norden E
authors: NE
authors: Huang
authors: Shih-Ann
authors: SA
authors: Chen
mesh_terms: D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000503:physiopathology* / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology* / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011667:Pulmonary Veins / Q000503:physiopathology* / Q000601:surgery*
keywords: atrial fibrillation; atrium; catheter ablation; electrocardiography; mapping