title: Accuracy of QT measurement in the EASI-derived 12-lead ECG.
abstract: The purpose of this study is to assess QT interval measurements from the EASI 12-lead ECG as compared to the standard 12-lead ECG. The QT interval was automatically measured in simultaneously recorded standard and EASI 12-lead ECGs, using a validated wavelet-based delineator. The agreement between the two sets of measurements was quantified both on a lead-by-lead basis and a multilead basis. The results show an acceptable agreement between QT measurements in the two lead systems, with correlation coefficients (CC) 0.91-0.98 depending on the lead. Standard deviations range from 9.2 ms to 26.4 ms depending on the selected lead. In a few patients large inter-system differences were found, mainly due to different T wave morphologies. Using a multilead delineation, QT intervals were considerably more stable than single-lead measurements and resulted in a much better agreement between the two lead systems (CC: 0.98, QT difference: 1.1 ms +/- 9.8 ms). Thus, EASI-derived 12-lead ECG may be used for reliable QT monitoring when the multilead delineation approach is adopted.
authors.affiliation: Commun. Technol. Group, Zaragoza Univ., Spain. jpmart@unizar.es
authors.forename: Juan P
authors.initials: JP
authors.lastname: Martínez
authors.forename: Pablo
authors.initials: P
authors.lastname: Laguna
authors.forename: Salvador
authors.initials: S
authors.lastname: Olmos
authors.forename: Olle
authors.initials: O
authors.lastname: Pahlm
authors.forename: Jonas
authors.initials: J
authors.lastname: Petersson
authors.forename: Leif
authors.initials: L
authors.lastname: Sörnmo
mesh_terms: D003936:Diagnosis, Computer-Assisted; D004562:Electrocardiography / Q000379:methods*; D004566:Electrodes; D004594:Electrophysiology / Q000379:methods; D004867:Equipment Design; D006801:Humans; D008133:Long QT Syndrome / Q000175:diagnosis* / Q000503:physiopathology*; D015588:Observer Variation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity