title: Predicting postoperative atrial fibrillation using CHA2DS2-VASc scores.
abstract: BACKGROUND
  Postoperative atrial fibrillation (POAF) is the most frequent complication of cardiac surgery and is associated with increased morbidity and mortality. Pharmacologic prophylaxis is the main method of preventing POAF but needs to be targeted to patients at high risk of developing POAF. The CHA2DS2-VASc scoring system is a clinical guideline for assessing ischemic stroke risk in patients with atrial fibrillation. The present study evaluated the utility of this scoring system in predicting the risk of developing de novo POAF in cardiac surgery patients.
  
  
  METHODS
  A total of 2385 patients undergoing cardiac surgery at our institution from 2008-2014 were identified for analysis. Each patient was assigned a CHA2DS2-VASc score and placed into a low- (score of 0), intermediate- (1), or high-risk (≥2) group. A multivariate regression model was created to control for known risk factors of atrial fibrillation.
  
  
  RESULTS
  POAF occurred in 380 of 2385 patients (15.9%). Mean CHA2DS2-VASc scores among patients with POAF and without POAF were 3.6 ± 1.7 and 2.8 ± 1.7, respectively (P < 0.0001). Using multivariate analysis, as a patient's CHA2DS2-VASc score rose from 0-9, the risk of developing POAF increased from 8.2%-42.3%. Each point increase was associated with higher odds of developing POAF (adjusted odds ratio, 1.27; 95% confidence interval, 1.18-1.36, P < 0.0001). Compared with low-risk patients, patients in the high-risk group were 5.21 times more likely to develop POAF (P < 0.0001).
  
  
  CONCLUSIONS
  The CHA2DS2-VASc algorithm is a simple risk-stratification tool that could be used to direct pharmacologic prophylaxis toward patients most likely to experience POAF.
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California.
authors.forename: Rustin G
authors.initials: RG
authors.lastname: Kashani
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California.
authors.forename: Sohail
authors.initials: S
authors.lastname: Sareh
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California.
authors.forename: Bradley
authors.initials: B
authors.lastname: Genovese
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California.
authors.forename: Christina
authors.initials: C
authors.lastname: Hershey
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California.
authors.forename: Corrine
authors.initials: C
authors.lastname: Rezentes
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California.
authors.forename: Richard
authors.initials: R
authors.lastname: Shemin
authors.affiliation: Division of Cardiology, Department of Medicine, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California.
authors.forename: Eric
authors.initials: E
authors.lastname: Buch
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California. Electronic address: Pbenharash@mednet.ucla.edu.
authors.forename: Peyman
authors.initials: P
authors.lastname: Benharash
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001281:Atrial Fibrillation / Q000453:epidemiology* / Q000209:etiology; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D015141:Los Angeles / Q000453:epidemiology; D008297:Male; D011183:Postoperative Complications / Q000453:epidemiology* / Q000209:etiology; D018570:Risk Assessment / Q000379:methods
keywords: Atrial fibrillation; CHA(2)DS(2)-VASc score; Cardiac surgery; Mortality; Pharmacologic prophylaxis; Postoperative complications; Prediction