title: Preoperative serum soluble receptor activator of nuclear factor-κB ligand and osteoprotegerin predict postoperative atrial fibrillation in patients undergoing cardiac valve surgery.
abstract: BACKGROUND
  Postoperative atrial fibrillation (POAF), a frequent complication after cardiac surgery, causes morbidity and prolongs hospitalization. A significant association between circulating osteoprotegerin concentration and atrial fibrillation incidence had been identified. Osteoprotegerin/receptor activator of nuclear factor-κB/receptor activator of nuclear factor-κB ligand (RANKL) axis may also contribute to the development and progression of AF. Herein we sought to determine whether preoperative serum soluble RANKL and osteoprotegerin and soluble RANKL/osteoprotegerin ratio are associated with the incidence of POAF in cardiac surgery patients.
  
  
  METHODS
  We enrolled 154 patients with preoperative sinus rhythm undergoing isolated cardiac valve surgery. Preoperative venous blood samples were obtained for measurement of serum soluble RANKL and osteoprotegerin. The POAF was defined as the characteristic arrhythmia lasting for at least 30 seconds before discharge. Comparison was made between patients without episode of POAF (sinus rhythm group, n=93) and patients experiencing POAF (atrial fibrillation group, n=61).
  
  
  RESULTS
  Serum levels of soluble RANKL and osteoprotegerin and soluble RANKL/osteoprotegerin ratio were significantly higher in the atrial fibrillation group than the sinus rhythm group. In multivariate survival regression, C-reactive protein, ejection fraction, left and right atrial diameters, preoperative use of beta-blocker, duration of ventilation, particularly serum soluble RANKL level, and soluble RANKL/osteoprotegerin ratio independently predicted POAF. According to receiver operating characteristic curve analysis, the best threshold values of serum soluble RANKL level and soluble RANKL/osteoprotegerin ratio for predicting POAF were 3.62 pmol/L and 0.51, respectively.
  
  
  CONCLUSIONS
  Elevated preoperative serum soluble RANKL level and soluble RANKL/osteoprotegerin ratio are independent predictors for POAF in patients undergoing cardiac valve surgery. These findings have important implications for identifying patients at higher risk of POAF who could be considered for prophylactic therapy.
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, China.
authors.forename: Hailong
authors.initials: H
authors.lastname: Cao
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhou
authors.forename: Yanhu
authors.initials: Y
authors.lastname: Wu
authors.forename: Qingguo
authors.initials: Q
authors.lastname: Li
authors.forename: Oluf Dimitri
authors.initials: OD
authors.lastname: Røe
authors.forename: Yijiang
authors.initials: Y
authors.lastname: Chen
authors.forename: Zhong
authors.initials: Z
authors.lastname: Wu
authors.forename: Dongjin
authors.initials: D
authors.lastname: Wang
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001281:Atrial Fibrillation / Q000209:etiology* / Q000401:mortality / Q000503:physiopathology; D015415:Biomarkers / Q000097:blood; D015331:Cohort Studies; D005260:Female; D006349:Heart Valve Diseases / Q000097:blood* / Q000601:surgery; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects* / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D053244:Osteoprotegerin / Q000097:blood*; D011183:Postoperative Complications / Q000175:diagnosis / Q000401:mortality; D011237:Predictive Value of Tests; D011300:Preoperative Care / Q000379:methods; D016016:Proportional Hazards Models; D053246:Receptor Activator of Nuclear Factor-kappa B / Q000097:blood*; D012044:Regression Analysis; D012189:Retrospective Studies; D018570:Risk Assessment; D012995:Solubility; D018709:Statistics, Nonparametric; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D053244:Osteoprotegerin; D053246:Receptor Activator of Nuclear Factor-kappa B
keywords: 24