title: Feasibility of predicting the risk of atrial fibrillation after coronary artery bypass surgery with logistic regression model.
abstract: OBJECTIVE
  The aim of this study was to determine the risk factors of postoperative atrial fibrillation (AF) after coronary artery bypass grafting and to create predictive model and to evaluate the effects of AF on patients outcome.
  
  
  METHODS
  Data of 3,676 consecutive patients were analysed to identify the predictors of AF. Multivariate logistic regression model was validated prospectively in 1,107 patients.
  
  
  RESULTS
  Increasing age (p < 0.001), preoperative use of digoxin (p = 003), need of intra-aortic balloon pump or inotropic medication in the weaning off cardiopulmonary by pass or during the first 24 hours postoperatively (p = 0.013), increasing body surface area (p = 0.006) and lower ejection fraction (p = 0.048) were independent risk factors for postoperative AF. The predictive model gave area under the receiver-operating characteristic (ROC) curve 0.682, 95% confidence interval 0.663-0.701, and p < 0.001. The patients with AF incidence had more postoperative stroke (p = 0.008), confusion (p < 0.001) severe gastrointestinal complications (p = 0.005), readmission to ICU (p < 0.001), longer ICU (p < 0.001) and hospital stay (p < 0.001) when compared with the patients who remained in sinus rhythm.
  
  
  CONCLUSIONS
  Logistic regression model with the parameters used was not accurate enough for clinical purposes. Postoperative AF is associated with postoperative stroke, severe gastrointestinal complications, readmission to ICU, and longer ICU and hospital stay.
authors.affiliation: Department of Surgery, Kuopio University Hospital, FIN - 70210 Kuopio, Finland. tapio.hakala@kuh.fi
authors.forename: T
authors.initials: T
authors.lastname: Hakala
authors.forename: O
authors.initials: O
authors.lastname: Pitkänen
authors.forename: M
authors.initials: M
authors.lastname: Hippeläinen
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000453:epidemiology*; D001026:Coronary Artery Bypass; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010359:Patient Readmission; D011183:Postoperative Complications / Q000453:epidemiology*; D011237:Predictive Value of Tests; D012372:ROC Curve