title: Sinus node dysfunction in atrial fibrillation patients: the evidence of regional atrial substrate remodelling.
abstract: OBJECTIVE
  It remains unclear as to whether regional atrial substrates of certain areas of the atrium in patients with atrial fibrillation (AF) can be related to sinoatrial node dysfunction. We investigated the relationship between the biatrial substrate characteristics and sinus node function in these patients.
  
  
  RESULTS
  The study enrolled 34 patients (aged 57 ± 11 years old; 20 males) who underwent catheter ablation for symptomatic paroxysmal AF. Sinus node dysfunction was defined as having corrected sinus node recovery time longer than 550 ms. Atrial substrate analyses of both atria and atrial conductive properties were investigated in patients with (Group 1) and without sinus node dysfunction (Group 2). The mean global bipolar voltage of both atria and the atrial refractory period were similar between the two groups. Regional analysis showed that the mean bipolar voltage for patients in Group 1 was lower than in Group 2 (1.0 ± 0.3 vs. 2.1 ± 0.7 mV, P < 0.001) only in the sinus node region, while the electrophysiological properties were similar for both groups in other anatomic regions of both atria. The right atrial total activation time was significantly longer (97 ± 9 vs. 89 ± 10 ms, P = 0.023) and the conduction velocity along the crista terminalis was significantly slower (1.0 ± 0.2 vs. 1.2 ± 0.3 m/s, P = 0.019) in Group 1 patients than in Group 2 patients.
  
  
  CONCLUSIONS
  In patients with AF, regional atrial remodelling near the sinus node area was associated with sinus node dysfunction.
authors: Division of Cardiology, Department of Medicine,  Taipei Veterans General Hospital, Taipei,  Taiwan.
authors: Hung-Yu
authors: HY
authors: Chang
authors: Yenn-Jiang
authors: YJ
authors: Lin
authors: Li-Wei
authors: LW
authors: Lo
authors: Shih-Lin
authors: SL
authors: Chang
authors: Yu-Feng
authors: YF
authors: Hu
authors: Cheng-Hung
authors: CH
authors: Li
authors: Tze-Fan
authors: TF
authors: Chao
authors: Wei-Hsian
authors: WH
authors: Yin
authors: Shih-Ann
authors: SA
authors: Chen
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications* / Q000503:physiopathology* / Q000601:surgery; D016280:Atrial Function, Right / Q000502:physiology; D054087:Atrial Septum / Q000503:physiopathology; D017115:Catheter Ablation; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006325:Heart Atria / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012804:Sick Sinus Syndrome / Q000150:complications* / Q000503:physiopathology*; D012849:Sinoatrial Node / Q000503:physiopathology*