title: Postoperative atrial fibrillation is not correlated to C-reactive protein.
abstract: BACKGROUND
  The peak incidence of postoperative atrial fibrillation (AF) occurs around the second postoperative day, a time at which serum inflammatory markers are elevated. The aim of this study was to investigate differences between patients with and without postoperative AF with special regard to C-reactive protein (CRP) serum levels.
  
  
  METHODS
  The study cohort included all heart surgery patients who had sinus rhythm preoperatively, survived postoperative day 3, and were operated on between July 1, 2004, and June 30, 2005 (n = 524). Any episode of AF during the first 7 postoperative days defined the patient as belonging to the postoperative AF group. Creatine kinase-myocardial band (CK-MB) was measured at postoperative day 1, and CRP was measured preoperatively and at postoperative day 3. Risk factors for postoperative AF were determined using bivariate and multivariate regression analysis.
  
  
  RESULTS
  Of 524 patients, 182 had at least one episode of AF (34.7%). Preoperative and postoperative CRP concentrations did not differ between the groups (postoperative CRP 175.4 +/- 64.4 versus 175.3 +/- 60.1 mg/L respectively, p = 0.99). Atrial fibrillation patients were significantly older (p < 0.001) and had higher CK-MB levels (33.6 +/- 53.1 microg/L versus 22.5 +/- 26.7 microg/L, respectively, p = 0.009). The odds ratio for postoperative AF with postoperative CK-MB greater than 70 microg/L was 3.5 (confidence interval: 1.4 to 8.6).
  
  
  CONCLUSIONS
  Postoperative AF has no correlation to the inflammatory marker CRP in heart surgery patients. Ischemic myocardial injury might predispose for postoperative AF.
authors: Department of Cardiothoracic Surgery and Anesthesiology, Orebro University Hospital, Orebro, Sweden. anders.ahlsson@orebroll.se
authors: Anders J
authors: AJ
authors: Ahlsson
authors: Lennart
authors: L
authors: Bodin
authors: Olof H
authors: OH
authors: Lundblad
authors: Anders G
authors: AG
authors: Englund
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000401:mortality; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis*; D006348:Cardiac Surgical Procedures / Q000009:adverse effects* / Q000379:methods; D016022:Case-Control Studies; D004562:Electrocardiography; D005112:Extracorporeal Circulation / Q000009:adverse effects; D005260:Female; D006324:Heart Arrest, Induced / Q000009:adverse effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis / Q000401:mortality; D011237:Predictive Value of Tests; D011336:Probability; D011379:Prognosis; D012016:Reference Values; D012189:Retrospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D015996:Survival Rate
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein