title: Elevated plasma norepinephrine level and sick sinus syndrome in patients with lone atrial fibrillation.
abstract: OBJECTIVE
  Plasma norepinephrine (NE) level can be a guide to mortality in patients with heart failure. This study aimed to evaluate the significance of plasma NE level compared with plasma natriuretic peptides (atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP)) levels in patients with atrial fibrillation (AF).
  
  
  METHODS
  Included in this study were 137 consecutive patients referred for catheter ablation of lone AF (paroxysmal in 90 and persistent in 47 patients). Blood samples for measurements of ANP, BNP and NE were drawn in the supine position before the procedure.
  
  
  RESULTS
  ANP, BNP and NE levels were greater in patients with persistent AF than in patients with paroxysmal AF (median (25th-75th centile)=28 (18-49) vs 69 (36-106), p<0.0001; 28 (15-50) vs 94 (39-156), p<0.0001; and 315 (223-502) vs 382 (299-517) pg/mL, p=0.04, respectively). NE level correlated weakly with ANP and BNP levels (r=0.28 and r=0.23, respectively, p<0.01 for both). BNP and NE levels differed between patients with and without recurrence of AF (55 (26-135) vs 35 (18-64), p=0.005 and 431 (323-560) vs 302 (225-436) pg/mL, p<0.001, respectively). Of note, only NE level was significantly greater in patients with symptomatic sick sinus syndrome (SSS) (n=21) than in those without SSS (560 (466-632) vs 321 (242-437) pg/mL, p<0.0001). Logistic regression analysis showed NE level to be the only independent discriminator for SSS (OR 1.006, 95% CI 1.002 to 1.010, p=0.001).
  
  
  CONCLUSIONS
  An increase in plasma NE level was observed in patients with AF and SSS. Although this implies a pathophysiological link between clinical manifestation of SSS and the autonomic nervous dysfunction, further studies are needed to clarify the mechanisms for this novel finding.
authors.affiliation: Division of Cardiovascular Medicine, Ibaraki Prefectural Central Hospital, Kasama, Japan Cardiovascular Division, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Yoshida
authors.affiliation: Cardiovascular Division, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kaneshiro
authors.affiliation: Division of Cardiovascular Medicine, Ibaraki Prefectural Central Hospital, Kasama, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Ito
authors.affiliation: Division of Cardiovascular Medicine, Ibaraki Prefectural Central Hospital, Kasama, Japan Cardiovascular Division, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Kimata
authors.affiliation: Division of Cardiovascular Medicine, Ibaraki Prefectural Central Hospital, Kasama, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Koda
authors.affiliation: Division of Cardiovascular Medicine, Ibaraki Prefectural Central Hospital, Kasama, Japan.
authors.forename: Daigo
authors.initials: D
authors.lastname: Hiraya
authors.affiliation: Division of Cardiovascular Medicine, Ibaraki Prefectural Central Hospital, Kasama, Japan.
authors.forename: Masako
authors.initials: M
authors.lastname: Baba
authors.affiliation: Division of Cardiovascular Medicine, Ibaraki Prefectural Central Hospital, Kasama, Japan.
authors.forename: Masako
authors.initials: M
authors.lastname: Misaki
authors.affiliation: Division of Cardiovascular Medicine, Ibaraki Prefectural Central Hospital, Kasama, Japan Cardiovascular Division, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Takeyasu
authors.affiliation: Ibaraki Health Service Association, Mito, Japan.
authors.forename: Iwao
authors.initials: I
authors.lastname: Yamaguchi
authors.affiliation: Cardiovascular Division, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Aonuma
mesh_terms: D000368:Aged; D019540:Area Under Curve; D001281:Atrial Fibrillation / Q000097:blood* / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery; D009320:Atrial Natriuretic Factor / Q000097:blood; D001341:Autonomic Nervous System / Q000378:metabolism / Q000503:physiopathology; D015415:Biomarkers / Q000097:blood; D017115:Catheter Ablation / Q000009:adverse effects; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D020097:Natriuretic Peptide, Brain / Q000097:blood; D009638:Norepinephrine / Q000097:blood*; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012372:ROC Curve; D012008:Recurrence; D012307:Risk Factors; D012804:Sick Sinus Syndrome / Q000097:blood* / Q000175:diagnosis / Q000503:physiopathology; D016896:Treatment Outcome; D015854:Up-Regulation
chemical_list: D015415:Biomarkers; D020097:Natriuretic Peptide, Brain; D009320:Atrial Natriuretic Factor; D009638:Norepinephrine