title: A predictive instrument using contrast echocardiography in patients presenting to the emergency department with chest pain and without ST-segment elevation.
abstract: OBJECTIVE
  Risk stratification of patients presenting to the emergency department (ED) with suspected cardiac chest pain (CP) and an undifferentiated electrocardiogram (ECG) is difficult. We hypothesized that in these patients a risk score incorporating clinical, ECG, and myocardial contrast echocardiography (MCE) variables would accurately predict adverse events occurring within the next 48 hours.
  
  
  METHODS
  Patients with CP lasting for 30 minutes or more who did not have ST-segment elevation on the ECG, were enrolled. Regional function (RF) and myocardial perfusion (MP) were assessed by MCE. A risk model was developed in the initial 1166 patients (cohort 1) and validated in subsequent 720 patients (cohort 2). Any abnormality or ST changes on ECG (odds ratio [OR] 2.5; 95% confidence interval [CI], 1.4-4.5, P = .002, and OR 2.9, 95% CI, 1.7-4.8, P < .001, respectively), abnormal RF with normal MP (OR 3.5, 95% CI, 1.8-6.5, P < .001), and abnormal RF with abnormal MP (OR 9.6, 95% CI, 5.8-16.0, P < .001) were found to be significant multivariate predictors of nonfatal myocardial infarction or cardiac death.
  
  
  RESULTS
  The estimate of the probability of concordance for the risk model was 0.82 for cohort 1 and 0.83 for cohort 2. The risk score in both cohorts stratified patients into 5 distinct risk groups with event rates ranging from 0.3% to 58%.
  
  
  CONCLUSIONS
  A simple predictive instrument has been developed from clinical, ECG, and MCE findings obtained at the bedside that can accurately predict events occurring within 48 hours in patients presenting to the ED with suspected cardiac CP and an ECG that is not diagnostic for acute ischemic injury. Its application could enhance care of patients with CP in the ED. For instance, patients with a risk score of 0 could be discharged from the ED without further workup. However, this needs to be validated in a multicenter study.
authors.affiliation: Division of Cardiovascular Medicine and Biostatistics, Oregon Health and Science University, Portland, Oregon 97239, USA.
authors.forename: Kevin
authors.initials: K
authors.lastname: Wei
authors.forename: Dawn
authors.initials: D
authors.lastname: Peters
authors.forename: Todd
authors.initials: T
authors.lastname: Belcik
authors.forename: Saul
authors.initials: S
authors.lastname: Kalvaitis
authors.forename: Lisa
authors.initials: L
authors.lastname: Womak
authors.forename: Diana
authors.initials: D
authors.lastname: Rinkevich
authors.forename: Khim-Leng
authors.initials: KL
authors.lastname: Tong
authors.forename: Kenneth
authors.initials: K
authors.lastname: Horton
authors.forename: Sanjiv
authors.initials: S
authors.lastname: Kaul
mesh_terms: D000368:Aged; D000787:Angina Pectoris / Q000000981:diagnostic imaging*; D004452:Echocardiography; D004562:Electrocardiography; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D018570:Risk Assessment