Assessment of QT-measurement accuracy using the 12-lead electrocardiogram derived from EASI leads

Juan Pablo Martinez, Pablo Laguna, Salvador Olmos, Olle Pahlm, Jonas Pettersson, Leif Sörnmo

Research output: Contribution to journalArticlepeer-review

10 Citations (SciVal)


The purpose of the present study is to assess QT-interval measurements from the EASI 12-lead electrocardiogram (ECG) as compared with the standard 12-lead ECG. The QT interval was automatically determined in simultaneously recorded standard and EASI 12-lead ECGs, using a validated wavelet-based delineator. The agreement between the 2 sets of measurements was quantified both on a lead-by-lead basis and a multilead basis with global definitions of QRS onset and T-wave end. The results show that the agreement between QT-interval measurements from the 2 lead systems is acceptable, with negligible mean differences and with correlation coefficients ranging from 0.91 to 0.98 depending on the lead studied. Although the SD shows a clear dependence on the selected lead (ranging from 9.2 to 26.4 milliseconds), differences are within the accepted tolerances for automatic delineation. In a few patients, large differences were found, mainly because of changes in morphology present in both lead systems. QT intervals measured by the multilead approach were considerably more stable than single-lead measurements and resulted in a much better agreement between the 2 lead systems (correlation coefficient, 0.98; QT difference, 1.1 +/- 9.8 milliseconds). Thus, the EASI 12-lead ECG may be used for reliable QT monitoring when the multilead delineation approach is adopted. (c) 2007 Elsevier Inc. All rights reserved.
Original languageEnglish
Pages (from-to)172-179
JournalJournal of Electrocardiology
Issue number2
Publication statusPublished - 2007

Subject classification (UKÄ)

  • Cardiac and Cardiovascular Systems


Dive into the research topics of 'Assessment of QT-measurement accuracy using the 12-lead electrocardiogram derived from EASI leads'. Together they form a unique fingerprint.

Cite this