title: Score indices for predicting electrophysiologic outcomes in patients with unexplained syncope.
abstract: BACKGROUND
  Our ability to predict a positive electrophysiologic (EP) study in the evaluation of unexplained syncope is suboptimal.
  
  
  OBJECTIVE
  In patients with unexplained syncope, we defined clinical predictors of bradyarrhythmia and ventricular tachycardia (VT) diagnosed during EP study, constructed diagnostic score indices for bradyarrhythmia and VT, and evaluated the predictive power of each score index.
  
  
  METHODS
  All patients evaluated in the Arrhythmia Clinic for unexplained syncope from January 1, 1996, through December 31, 1998, were identified and enrolled in the study. Five hundred eight patients (325 [64%] men; mean+/-SD age, 64+/-17 years) underwent EP testing. We analyzed elements from historical data and noninvasive laboratory findings as predictors of bradyarrhythmia and VT diagnosed on EP study.
  
  
  RESULTS
  Fifty-eight patients (11%) had sinus node dysfunction, 94 (19%) had atrioventricular (AV) node disease, 92 (18%) had His-Purkinje system disease, and 101 (20%) had VT. Models were fit using logistic regression analysis. Predictors were assigned weighted scores, and a score index was formulated. The area under the curve associated with sinus node dysfunction, AV node disease, His-Purkinje system disease, and VT models was 0.64, 0.60, 0.84, and 0.60, respectively.
  
  
  CONCLUSIONS
  We have constructed diagnostic score indices for EP outcomes of bradyarrhythmia and VT in syncope. Of all the score indices, the model for His-Purkinje system disease has the highest predictive power.
authors.affiliation: Division of Cardiovascular Diseases, Department of Emergency Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA, and Department of Internal Medicine, University of Amsterdam, Academic Medical Centre, The Netherlands.
authors.forename: Lin Y
authors.initials: LY
authors.lastname: Chen
authors.forename: Arshad
authors.initials: A
authors.lastname: Jahangir
authors.forename: Wyatt W
authors.initials: WW
authors.lastname: Decker
authors.forename: Peter A
authors.initials: PA
authors.lastname: Smars
authors.forename: Wouter
authors.initials: W
authors.lastname: Wieling
authors.forename: David O
authors.initials: DO
authors.lastname: Hodge
authors.forename: Bernard J
authors.initials: BJ
authors.lastname: Gersh
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Hammill
authors.forename: Win-Kuang
authors.initials: WK
authors.lastname: Shen
mesh_terms: D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000453:epidemiology*; D001919:Bradycardia / Q000175:diagnosis / Q000453:epidemiology; D015897:Comorbidity; D004562:Electrocardiography / Q000379:methods*; D022062:Electrophysiologic Techniques, Cardiac / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D017063:Outcome Assessment, Health Care / Q000379:methods*; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013575:Syncope / Q000175:diagnosis* / Q000453:epidemiology*; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000453:epidemiology