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PubMed · 9535497

Algorithms for computerized QT analysis.

Q Xue·S Reddy
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Abstract

Several methods for measurement of the offset, peak, and morphology of the T wave in multilead ECGs are reviewed and compared. The T wave offset is the most important and also the most difficult measurement for analysis of QT interval dispersion. Measurement methods compared here include (1) the point at which the T wave intersects the isoelectric line plus a threshold; (2) the point at which the derivative of T wave intersects the isoelectric line plus a threshold; (3) the intersection of the maximum slope of the T wave and the isoelectric line; (4) the intersection of a line fitted by least squares to the maximum slope of the T wave and an isoelectric line (LSI); and (5) the point at which the T wave area reaches 90% of the entire T wave area (TA). The reproducibility tests show that the LSI method has the best reproducibility of all the algorithms examined. Although the T wave peak is better defined than the T wave offset, it is not simple to find the right peak when there are multiple T wave peaks and when the T wave is flat and/or noisy. Methods to find T wave patterns with multiple peaks and to locate the point at which the T wave is flat and noisy are therefore reviewed here. Finally, the principal component analysis-based T wave complexity measurement and its relation to other QT interval dispersion measurements are discussed.

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AlgorithmsElectrocardiographyElectrophysiologyHeartHumansReproducibility of ResultsSignal Processing, Computer-AssistedComparative StudyJournal Article

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BibTeXRIS

Q Xue, S Reddy. 1998. Algorithms for computerized QT analysis.. https://doi.org/10.1016/s0022-0736(98)80072-1

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