title: Accuracy of a 12-lead electrocardiogram in screening patients with suspected heart failure for open access echocardiography: a systematic review and meta-analysis.
abstract: OBJECTIVE
  The aim of this study was to examine the usefulness of 12-lead electrocardiogram in screening patients with suspected heart failure for open access echocardiography. We carried out a systematic review and meta-analysis of published observational studies. Published studies were identified in the Medline and Embase databases, this was supplemented by key texts, personal reference collections and examining the cited references in the above sources. English language articles in which patients were referred from primary care with a presumptive diagnosis of heart failure to an open access echocardiography service were reviewed. We included studies that reported both electrocardiography findings and echocardiography as a reference standard. Primary outcome measures were sensitivity and specificity, meta-analysed simultaneously to produce a Summary Receiver Operating Characteristic (SROC) curve.
  
  
  RESULTS
  Four trials were identified which satisfied the inclusion criteria, including 1419 people with a potential diagnosis of heart failure referred for open access echocardiography. Estimates of sensitivity and specificity varied greatly in individual studies. The area under the SROC curve was 0.84 (95% Cl: 0.33 to 1.00).
  
  
  CONCLUSIONS
  A 12-lead electrocardiogram is an inadequate screening tool for identifying patients with suspected heart failure who require echocardiography. Further research is required to determine the usefulness of other screening strategies including B-type natriuretic peptide in screening patients with suspected heart failure who need referral for open access echocardiography.
authors.affiliation: Department of Health Sciences, Division of General Practice and Primary Health Care, University of Leicester, Leicester General Hospital, Leicester, UK. kk22@le.ac.uk
authors.forename: K
authors.initials: K
authors.lastname: Khunti
authors.forename: I
authors.initials: I
authors.lastname: Squire
authors.forename: K R
authors.initials: KR
authors.lastname: Abrams
authors.forename: A J
authors.initials: AJ
authors.lastname: Sutton
mesh_terms: D004562:Electrocardiography; D006333:Heart Failure / Q000175:diagnosis* / Q000000981:diagnostic imaging; D012372:ROC Curve; D012680:Sensitivity and Specificity; D014463:Ultrasonography; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis