title: The predictive role of renal function and systemic inflammation on the onset of de novo atrial fibrillation after cardiac surgery.
abstract: BACKGROUND
  The association between postoperative atrial fibrillation (POAF) and renal function was previously grounded in patients undergoing coronary artery bypass grafting through unknown mechanisms. We aim to investigate the association between renal function and POAF in a cohort composed mostly of patients undergoing valve surgery and to explore the role of inflammation as a pathogenic mechanism linking renal dysfunction and arrhythmogenesis.
  
  
  METHODS
  Altogether 444 patients who underwent cardiac surgery without previous history of atrial fibrillation were analysed. Serum creatinine and high sensitivity C-reactive protein (hs-CRP) concentrations were obtained at baseline and on the 3rd, 8th and 15th postoperative day; estimated glomerular filtration rate (eGFR) was calculated by the Modified Diet Renal Disease (MDRD) formula. Patients were divided into three groups on the basis of baseline eGFR.
  
  
  RESULTS
  Overall, 173 (39%) patients developed POAF, 29.5% in the group with normal eGFR (≥90 ml/min/1.73 m(2)), 43.3% among patients with eGFR 60-90 ml/min/1.73 m(2) and 55.6% in the group with eGFR ≤60 ml/min/1.73 m(2). Patients developing POAF had lower eGFR on all the samples. At baseline preoperatively hs-CRP levels did not differ in the two groups.On multivariate analysis, age and eGFR were identified as independent predictors of POAF. The risk of POAF progressively increased from mild impairment (odds ratio (OR) 1.59, 95% confidence interval (CI) 1.01-2.50) to severe reduction of renal function (OR 2.35, 95% CI 1.25-4.48).
  
  
  CONCLUSIONS
  Age and eGFR were identified as the strongest predictors of POAF in a population largely composed of valve surgery patients. Renal function, even from early stage, is independently associated with the increasing risk of developing POAF.
authors.affiliation: Cardiovascular Department, San Raffaele Scientific Institute, Italy.
authors.forename: Luca R
authors.initials: LR
authors.lastname: Limite
authors.affiliation: Cardiovascular Department, San Raffaele Scientific Institute, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Magnoni
authors.affiliation: Cardiovascular Department, San Raffaele Scientific Institute, Italy.
authors.forename: Martina
authors.initials: M
authors.lastname: Berteotti
authors.affiliation: Cardiovascular Department, San Raffaele Scientific Institute, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Peretto
authors.affiliation: Cardiovascular Department, San Raffaele Scientific Institute, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Durante
authors.affiliation: Cardiovascular Department, San Raffaele Scientific Institute, Italy.
authors.forename: Nicole
authors.initials: N
authors.lastname: Cristell
authors.affiliation: Cardiovascular Department, San Raffaele Scientific Institute, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Laricchia
authors.affiliation: Cardiovascular Department, San Raffaele Scientific Institute, Italy.
authors.forename: Paolo G
authors.initials: PG
authors.lastname: Camici
authors.affiliation: Cardiovascular Department, San Raffaele Scientific Institute, Italy.
authors.forename: Ottavio
authors.initials: O
authors.lastname: Alfieri
authors.affiliation: Cardiovascular Department, San Raffaele Scientific Institute, Italy cianflone.domenico@hsr.it.
authors.forename: Domenico
authors.initials: D
authors.lastname: Cianflone
mesh_terms: D000367:Age Factors; D000368:Aged; D001281:Atrial Fibrillation / Q000209:etiology*; D002097:C-Reactive Protein / Q000032:analysis*; D006348:Cardiac Surgical Procedures; D003404:Creatinine / Q000097:blood; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007249:Inflammation / Q000097:blood; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011183:Postoperative Complications; D051437:Renal Insufficiency / Q000209:etiology
chemical_list: D002097:C-Reactive Protein; D003404:Creatinine
keywords: Atrial fibrillation; cardiac surgery; inflammation; renal function