title: Sensitivity and specificity of automated detection of early repolarization in standard 12-lead electrocardiography.
abstract: BACKGROUND
  Early repolarization (ER) is defined as an elevation of the QRS-ST junction in at least two inferior or lateral leads of the standard 12-lead electrocardiogram (ECG). Our purpose was to create an algorithm for the automated detection and classification of ER.
  
  
  METHODS
  A total of 6,047 electrocardiograms were manually graded for ER by two experienced readers. The automated detection of ER was based on quantification of the characteristic slurring or notching in ER-positive leads. The ER detection algorithm was tested and its results were compared with manual grading, which served as the reference.
  
  
  RESULTS
  Readers graded 183 ECGs (3.0%) as ER positive, of which the algorithm detected 176 recordings, resulting in sensitivity of 96.2%. Of the 5,864 ER-negative recordings, the algorithm classified 5,281 as negative, resulting in 90.1% specificity. Positive and negative predictive values for the algorithm were 23.2% and 99.9%, respectively, and its accuracy was 90.2%. Inferior ER was correctly detected in 84.6% and lateral ER in 98.6% of the cases.
  
  
  CONCLUSIONS
  As the automatic algorithm has high sensitivity, it could be used as a prescreening tool for ER; only the electrocardiograms graded positive by the algorithm would be reviewed manually. This would reduce the need for manual labor by 90%.
authors.affiliation: Medical Research Center Oulu, University of Oulu and University Hospital of Oulu, Oulu, Finland.
authors.forename: Tuomas
authors.initials: T
authors.lastname: Kenttä
authors.affiliation: Division of Cardiology, Department of Medicine, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Kimmo
authors.initials: K
authors.lastname: Porthan
authors.affiliation: Medical Research Center Oulu, University of Oulu and University Hospital of Oulu, Oulu, Finland.
authors.forename: Jani T
authors.initials: JT
authors.lastname: Tikkanen
authors.affiliation: Department of Biomedical Engineering and Computational Science, Aalto University, Helsinki, Finland.
authors.forename: Heikki
authors.initials: H
authors.lastname: Väänänen
authors.affiliation: Division of Cardiology, Department of Medicine, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Lasse
authors.initials: L
authors.lastname: Oikarinen
authors.affiliation: Division of Cardiology, Department of Medicine, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Matti
authors.initials: M
authors.lastname: Viitasalo
authors.affiliation: National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: Hannu
authors.initials: H
authors.lastname: Karanko
authors.affiliation: National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: Maarit
authors.initials: M
authors.lastname: Laaksonen
authors.affiliation: Medical Research Center Oulu, University of Oulu and University Hospital of Oulu, Oulu, Finland.
authors.forename: Heikki V
authors.initials: HV
authors.lastname: Huikuri
mesh_terms: D000328:Adult; D000465:Algorithms; D004562:Electrocardiography; D005260:Female; D005387:Finland; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity
keywords: J point elevation; cardiac; early repolarization; sensitivity; specificity