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SVD-based on-line exercise ECG signal orthogonalization.

B Acar·H Köymen
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Abstract

An orthogonalization method to eliminate unwanted signal components in standard 12-lead exercise electrocardiograms (ECG's) is presented in this work. A singular-value-decomposition-based algorithm is proposed to decompose the signal into two time-orthogonal subspaces; one containing the ECG and the other containing artifacts like baseline wander and electromyogram. The method makes use of redundancy in 12-lead ECG. The same method is also tested for reconstruction of a completely lost channel. The online implementation of the method is given. It is observed that the first two decomposed channels with highest energy are sufficient to reconstruct the ST-segment and J-point. The dimension of the signal space, on the other hand, does not exceed three. Data from 23 patients, with duration ranging from 9 to 21 min, are used.

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AlgorithmsElectrocardiographyExercise TestHumansLinear ModelsMicrocomputersSignal Processing, Computer-AssistedSoftware DesignJournal Article

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BibTeXRIS

B Acar, H Köymen. 1999. SVD-based on-line exercise ECG signal orthogonalization.. https://doi.org/10.1109/10.748984

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