title: Improved risk stratification in unstable angina: identification of patients at low risk for in-hospital cardiac events by admission echocardiography.
abstract: BACKGROUND
  Current protocols for risk stratification of patients with acute chest pain syndromes rely on clinical parameters and are oriented toward identification of patients at high risk for adverse cardiac events; however, this paradigm for risk stratification does not adequately address the observation that adverse cardiac events are relatively uncommon in this population. In an era of cost containment, consideration also should be given to identification of patients at low risk for adverse cardiac events, who may be safely discharged without expensive inpatient hospitalization.
  
  
  OBJECTIVE
  The purpose of this study was to develop echocardiographic predictors that identify unstable angina patients at low risk for adverse cardiac events and that discriminate between low- and high-risk patients.
  
  
  METHODS
  The predictive accuracy of retrospectively determined echocardiographic predictors were compared in a population-based sample of 66 consecutive unstable angina patients undergoing echocardiography within 24 h of admission.
  
  
  RESULTS
  Echocardiographic predictors of adverse events included wall motion score index > or = 0.2, ejection fraction < or = 40%, and mitral regurgitation severity > 2. One or more echocardiographic predictors of adverse events were present in 32 patients (48%). A composite echocardiographic predictor of adverse events was specific, had a high positive predictive value for the identification of high-risk patients, and discriminated between unstable angina patients at high and low risk for adverse cardiac events.
  
  
  CONCLUSIONS
  Echocardiographic predictors of adverse events are specific and discriminate between unstable angina patients at high and low risk for adverse cardiac events.
authors.affiliation: Department of Medicine, Rush Medical College, Chicago, Illinois, USA.
authors.forename: J H
authors.initials: JH
authors.lastname: Stein
authors.forename: A
authors.initials: A
authors.lastname: Neumann
authors.forename: L M
authors.initials: LM
authors.lastname: Preston
authors.forename: B J
authors.initials: BJ
authors.lastname: Vandenberg
authors.forename: J E
authors.initials: JE
authors.lastname: Parrillo
authors.forename: J E
authors.initials: JE
authors.lastname: Calvin
authors.forename: R H
authors.initials: RH
authors.lastname: Marcus
mesh_terms: D000208:Acute Disease; D000368:Aged; D000789:Angina, Unstable / Q000150:complications / Q000175:diagnosis* / Q000401:mortality; D002637:Chest Pain / Q000175:diagnosis; D003627:Data Interpretation, Statistical; D004452:Echocardiography; D005260:Female; D006333:Heart Failure / Q000209:etiology; D006760:Hospitalization; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000209:etiology; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012189:Retrospective Studies; D012307:Risk Factors; D013318:Stroke Volume; D017180:Tachycardia, Ventricular / Q000209:etiology; D013997:Time Factors; D014693:Ventricular Fibrillation / Q000209:etiology