title: [Predictors of acute coronary syndrome without ST segment elevation and risk stratification in the chest pain unit].
abstract: BACKGROUND
  Nearly 10% of patients with an actual acute coronary syndrome (ACS) are discharged with an inadequate diagnosis.
  
  
  OBJECTIVE
  To select clinical and laboratory predictors to identify patients with a high likelihood of ACS in the Chest Pain Unit.
  
  
  METHODS
  Prospective evaluation of patients consulting in a Chest Pain Unit of a University Hospital. Initial assessment was standardized and included evaluation of pain characteristics, electrocardiogram and Troponin I. Independent predictors of ACS were identified with a multiple logistic regression.
  
  
  RESULTS
  In a four years period, 1,168 patients aged 62+/-23 years (69% males), were studied. After initial evaluation, 62% of the patients were admitted to the hospital for further testing and in 71% of them, a definite diagnosis of ACS was made. No events were reported by patients directly discharged from the Chest Pain Unit. Independent predictors associated with a higher likelihood of ACS were an abnormal electrocardiogram at the initial evaluation (Odds ratio (OR) 5.37, 95% confidence intervals (CI) 3.61-7.99), two or more cardiovascular risk factors (OR 2.16, 95% CI 1.21-2.84), cervical irradiation of the pain (OR 1.84, 95% CI 1.25-2.69), age over 65 years (OR 1.73, 95% CI (1.32-2.27) and a Troponin I above the upper normal limit (OR: 5.68, 95% CI 3.72-8.29).
  
  
  CONCLUSIONS
  Simple clinical findings allow an appropriate identification of patients with a high likelihood of ACS without specialized methods for myocardial ischemia detection.
authors.affiliation: Departamento de Enfermedades Cardiovasculares, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Luigi A
authors.initials: LA
authors.lastname: Gabrielli
authors.forename: Pablo F
authors.initials: PF
authors.lastname: Castro
authors.forename: Hugo E
authors.initials: HE
authors.lastname: Verdejo
authors.forename: Paul A
authors.initials: PA
authors.lastname: McNab
authors.forename: Silvana A
authors.initials: SA
authors.lastname: Llevaneras
authors.forename: José M
authors.initials: JM
authors.lastname: Mardonez
authors.forename: Ramón L
authors.initials: RL
authors.lastname: Corbalán