title: A vector-based, 5-electrode, 12-lead monitoring ECG (EASI) is equivalent to conventional 12-lead ECG for diagnosis of acute coronary syndromes.
abstract: OBJECTIVE
  The conventional 12-lead electrocardiogram (cECG) derived from 10 electrodes using a cardiograph is the gold standard for diagnosing myocardial ischemia. This study tested the hypothesis that a new 5-electrode 12-lead vector-based ECG (EASI; Philips Medical Systems, formerly Hewlett Packard Co, Boeblingen, Germany) patient monitoring system is equivalent to cECG in diagnosing acute coronary syndromes (ACSs).
  
  
  METHODS
  Electrocardiograms (EASI and cECG) were obtained in 203 patients with chest pain on admission and 4 to 8 hours later. Both types of ECGs were graded as ST-elevation myocardial infarction if at least 1 of the 2 consecutive recordings showed ST elevation more than 0.2 mV, as ACS if one or both showed ST elevation less than 0.2 mV, T-wave inversion, or ST depression. Otherwise, the ECG was graded negative.
  
  
  RESULTS
  Final diagnosis was identical in 177 patients (87%; 95% confidence interval [CI], 82%-91%; kappa = 0.81; SE = 0.035). ST-elevation myocardial infarction was correctly identified or excluded by EASI with a specificity of 94% (95% CI, 89%-97%) and a sensitivity of 93% (95% CI, 86%-97%; using cECG as the gold standard). Of 118 patients with enzyme elevations, an almost identical number (72 [61% by EASI] and 73 [62% by cECG]) had ST elevations. Both techniques were equivalent in predicting subsequent enzyme elevation (identical, 108/143; 75% of ACS and ST-elevation myocardial infarction ECGs by EASI and cECG). Thus, both ECG methods had exactly the same specificity of 59% (95% CI, 48%-69%) and sensitivity of 91% (95% CI, 85%-96%) for detecting myocardial injury.
  
  
  CONCLUSIONS
  EASI is equivalent to cECG for the diagnosis of myocardial ischemia.
authors.affiliation: Robert Bosch Hospital Stuttgart, Germany. drwehr@t-online.de
authors.forename: Gabriele
authors.initials: G
authors.lastname: Wehr
authors.forename: Ron J
authors.initials: RJ
authors.lastname: Peters
authors.forename: Khalifé
authors.initials: K
authors.lastname: Khalifé
authors.forename: Adrian P
authors.initials: AP
authors.lastname: Banning
authors.forename: Volker
authors.initials: V
authors.lastname: Kuehlkamp
authors.forename: Anthony F
authors.initials: AF
authors.lastname: Rickards
authors.forename: Udo
authors.initials: U
authors.lastname: Sechtem
mesh_terms: D002637:Chest Pain / Q000209:etiology*; D004562:Electrocardiography / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D006801:Humans; D017202:Myocardial Ischemia / Q000097:blood / Q000175:diagnosis*; D011446:Prospective Studies; D015203:Reproducibility of Results