title: Incremental prognostic value of the exercise electrocardiogram in the initial assessment of patients with suspected angina: cohort study.
abstract: OBJECTIVE
  To determine whether resting and exercise electrocardiograms (ECGs) provide prognostic value that is incremental to that obtained from the clinical history in ambulatory patients with suspected angina attending chest pain clinics.
  
  
  METHODS
  Multicentre cohort study.
  
  
  METHODS
  Rapid access chest pain clinics of six hospitals in England.
  
  
  METHODS
  8176 consecutive patients with suspected angina and no previous diagnosis of coronary artery disease, all of whom had a resting ECG recorded. 4848 patients with a summary exercise ECG result recorded (positive, negative, equivocal for ischaemia) comprised the summary ECG subset of whom 1422 with more detailed exercise ECG data recorded comprised the detailed ECG subset.
  
  
  METHODS
  Composite of death due to coronary heart disease or non-fatal acute coronary syndrome during median follow-up of 2.46 years.
  
  
  RESULTS
  Receiver operating characteristics curves for the basic clinical assessment model alone and with the results of resting ECGs were superimposed with little difference in the C statistic. With the exercise ECGs the C statistic in the summary ECG subset increased from 0.70 (95% confidence interval 0.68 to 0.73) to 0.74 (0.71 to 0.76) and in the detailed ECG subset from 0.74 (0.70 to 0.79) to 0.78 (0.74 to 0.82). However, risk stratified cumulative probabilities of the primary end point at one year and six years for all three prognostic indices (clinical assessment only; clinical assessment plus resting ECG; clinical assessment plus resting ECG plus exercise ECG) showed only small differences at all time points and at all levels of risk.
  
  
  CONCLUSIONS
  In ambulatory patients with suspected angina, basic clinical assessment encompasses nearly all the prognostic value of resting ECGs and most of the prognostic value of exercise ECGs. The limited incremental value of these widely applied tests emphasises the need for more effective methods of risk stratification in this group of patients.
authors.affiliation: Newham University Hospital, London.
authors.forename: Neha
authors.initials: N
authors.lastname: Sekhri
authors.forename: Gene S
authors.initials: GS
authors.lastname: Feder
authors.forename: Cornelia
authors.initials: C
authors.lastname: Junghans
authors.forename: Sandra
authors.initials: S
authors.lastname: Eldridge
authors.forename: Athavan
authors.initials: A
authors.lastname: Umaipalan
authors.forename: Rashmi
authors.initials: R
authors.lastname: Madhu
authors.forename: Harry
authors.initials: H
authors.lastname: Hemingway
authors.forename: Adam D
authors.initials: AD
authors.lastname: Timmis
mesh_terms: D054058:Acute Coronary Syndrome / Q000175:diagnosis; D000787:Angina Pectoris / Q000209:etiology*; D015331:Cohort Studies; D003324:Coronary Artery Disease / Q000175:diagnosis; D004562:Electrocardiography / Q000379:methods*; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D012680:Sensitivity and Specificity