title: Comparison of usefulness of computer assisted continuous 48-h 3-lead with 12-lead ECG ischaemia monitoring for detection and quantitation of ischaemia in patients with unstable angina.
abstract: OBJECTIVE
  The selection of ECG leads used for ST monitoring may influence detection and quantitation of ischaemia.
  
  
  METHODS
  We compared on-line continuous 48-h 12-lead against 3-lead ST monitoring in 130 unstable angina patients (Mortara. ELI-100). Onset and offset of ST episodes were defined by the lead with the first > or = 100 microV ST change relative to baseline and the lead with the latest return to baseline ST level, respectively. ST episodes were calculated for 12 leads and 3 leads (V2, V5, III) separately.
  
  
  RESULTS
  ST episodes were detected in 88 patients (77%) by 12-lead and in 71 patients (62%) by 3-lead ST monitoring (P < 0.02). The median number (25.75%) of episodes/patient was 1 (0.3) for 3-lead and 2 (1.6) for 12-lead (P < 0.0001). The total duration of ischaemia detected during 12-lead far exceeded 3-lead monitoring: 12.3 (1, 58.2) and 1.7 (0, 23.3) min respectively (P < 0.0001). The probability of recurrent ischaemia declined most during the first 24 h of monitoring. After a period without ST changes of 1, 12, 24 and 36 h, the probabilities of recurrent ischaemia were 63, 31, 14 and 9%, respectively.
  
  
  CONCLUSIONS
  Continuous 12-lead ST monitoring increases detection rate and duration of ST episodes compared to 3-lead ST monitoring. The use of continuous 12-lead ECG monitoring devices on emergency wards and coronary care units is recommended.
authors.affiliation: Division of Cardiology, University Hospital Dijkzigt, Erasmus University Rotterdam, The Netherlands.
authors.forename: P
authors.initials: P
authors.lastname: Klootwijk
authors.forename: S
authors.initials: S
authors.lastname: Meij
authors.forename: G A
authors.initials: GA
authors.lastname: von Es
authors.forename: E J
authors.initials: EJ
authors.lastname: Müller
authors.forename: V A
authors.initials: VA
authors.lastname: Umans
authors.forename: T
authors.initials: T
authors.lastname: Lenderink
authors.forename: M L
authors.initials: ML
authors.lastname: Simoons
mesh_terms: D000789:Angina, Unstable / Q000150:complications*; D016009:Chi-Square Distribution; D003936:Diagnosis, Computer-Assisted; D004562:Electrocardiography / Q000295:instrumentation* / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods; D017202:Myocardial Ischemia / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D012680:Sensitivity and Specificity