title: Predictive significance of plasma levels of interleukin-6 and high-sensitivity C-reactive protein in atrial fibrillation after coronary artery bypass surgery.
abstract: BACKGROUND
  Postoperative atrial fibrillation (AF) plays a major role in the determination of hemodynamic deterioration and can be associated with cardiovascular events after coronary artery surgery. Elevated interleukin (IL)-6 and C-reactive protein (CRP) levels in patients with AF suggest a role of inflammation in the pathogenesis of AF. We conducted a study to investigate the correlation between postoperative AF and IL-6 and high-sensitivity CRP (hsCRP).
  
  
  METHODS
  Forty-nine patients with a mean age of 60.3 +/- 10.7 years were enrolled in this study. Preoperative and postoperative first day blood samples were collected to assess the IL-6 and hsCRP levels. IL-6 levels were measured by enzyme-linked immunosorbent assay, and hsCRP was measured by rate turbidimetry method.
  
  
  RESULTS
  Fourteen patients (28.5%) developed AF postoperatively. Patients who developed AF showed elevated serum concentrations of postoperative first day IL-6 (P < .001), preoperative hsCRP (P < .005), and postoperative first day hsCRP (P < 0.001). Preoperative hsCRP levels (P < .002) and postoperative first day IL-6 (P < .001) and hsCRP (P < 0.001) levels were associated with prolonged endotracheal intubation time. Prolonged intensive care unit stay showed significant correlations with elevated levels of preoperative hsCRP (P < 0.002) and postoperative first day IL-6 (P < 0.001) and hsCRP (P < 0.001). There was also statistical significance between the AF+ and AF- groups regarding intensive care unit stay and endotracheal intubation times (P < .001 and P < .001, respectively). Cut-off points for postoperative first day IL-6, preoperative hsCRP, and postoperative first day hsCRP were 46.4 pg/mL (sensitivity = 92.9% and specificity = 80%), 0.46 mg/L (sensitivity = 71% and specificity = 75%), and 17.9 mg/L (sensitivity = 92.9% and specificity = 78%), respectively.
  
  
  CONCLUSIONS
  Elevated IL-6 and hsCRP levels in patients with postoperative AF suggest inflammatory components have a role of in the pathogenesis of AF.
authors.affiliation: Department of Cardiovascular Surgery, Hacettepe University, Faculty of Medicine, Ankara, Turkey.
authors.forename: Halil Ibrahim
authors.initials: HI
authors.lastname: Ucar
authors.forename: Mustafa
authors.initials: M
authors.lastname: Tok
authors.forename: Enver
authors.initials: E
authors.lastname: Atalar
authors.forename: Omer Faruk
authors.initials: OF
authors.lastname: Dogan
authors.forename: Mehmet
authors.initials: M
authors.lastname: Oc
authors.forename: Bora
authors.initials: B
authors.lastname: Farsak
authors.forename: Murat
authors.initials: M
authors.lastname: Guvener
authors.forename: Mustafa
authors.initials: M
authors.lastname: Yilmaz
authors.forename: Riza
authors.initials: R
authors.lastname: Dogan
authors.forename: Metin
authors.initials: M
authors.lastname: Demircin
authors.forename: Ilhan
authors.initials: I
authors.lastname: Pasaoglu
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000097:blood / Q000175:diagnosis*; D002097:C-Reactive Protein / Q000378:metabolism*; D016009:Chi-Square Distribution; D017023:Coronary Angiography; D001026:Coronary Artery Bypass / Q000009:adverse effects* / Q000379:methods; D003327:Coronary Disease / Q000000981:diagnostic imaging / Q000601:surgery*; D005260:Female; D006084:Graft Rejection; D006085:Graft Survival; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood; D015850:Interleukin-6 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000097:blood / Q000175:diagnosis; D011237:Predictive Value of Tests; D011336:Probability; D011379:Prognosis; D011446:Prospective Studies; D012372:ROC Curve; D015996:Survival Rate
chemical_list: D018836:Inflammation Mediators; D015850:Interleukin-6; D002097:C-Reactive Protein