ASSESSMENT OF NOISE IMPACT IN SAMPLE ENTROPY FOR THE NON-INVASIVE ORGANIZATION ESTIMATION OF ATRIAL FIBRILLATION

Raúl Alcaraz, José Joaquín Rieta

Abstract

In recent studies, Sample Entropy (SampEn) has demonstrated that can be a very promising non-linear index to assess atrial fibrillation (AF) organization from surface ECG recordings. However, non-linear regularity metrics are notably sensitive to noise. Thereby, in the present work, the effect that noise provokes in AF organization estimation based on SampEn is analyzed. Given that AF organization was estimated by computing SampEn over the atrial activity (AA) signal, to evaluate the noise impact on AA regularity, 25 synthetic signals with different organization degrees were generated following a published model. Noise coming from real ECG recordings with different energy levels was added to the synthesized AA signals to obtain different signal to noise ratios (SNR). Results showed that SampEn, i.e., the AA irregularity, increased with noise, thus hiding the differences between organized and disorganized recordings. Precisely, in the presence of noise, SampEn values were increased, in average, by factors of 1.64, 4.46, 9.46 and 14.23 for SNRs of 24, 15, 9 and 3 dB, respectively. As a conclusion, a successful AF organization evaluation via SampEn requires a proper noise reduction in the AA signal.

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in Harvard Style

Alcaraz R. and Joaquín Rieta J. (2010). ASSESSMENT OF NOISE IMPACT IN SAMPLE ENTROPY FOR THE NON-INVASIVE ORGANIZATION ESTIMATION OF ATRIAL FIBRILLATION . In Proceedings of the Third International Conference on Bio-inspired Systems and Signal Processing - Volume 1: BIOSIGNALS, (BIOSTEC 2010) ISBN 978-989-674-018-4, pages 393-396. DOI: 10.5220/0002692103930396


in Bibtex Style

@conference{biosignals10,
author={Raúl Alcaraz and José Joaquín Rieta},
title={ASSESSMENT OF NOISE IMPACT IN SAMPLE ENTROPY FOR THE NON-INVASIVE ORGANIZATION ESTIMATION OF ATRIAL FIBRILLATION},
booktitle={Proceedings of the Third International Conference on Bio-inspired Systems and Signal Processing - Volume 1: BIOSIGNALS, (BIOSTEC 2010)},
year={2010},
pages={393-396},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0002692103930396},
isbn={978-989-674-018-4},
}


in EndNote Style

TY - CONF
JO - Proceedings of the Third International Conference on Bio-inspired Systems and Signal Processing - Volume 1: BIOSIGNALS, (BIOSTEC 2010)
TI - ASSESSMENT OF NOISE IMPACT IN SAMPLE ENTROPY FOR THE NON-INVASIVE ORGANIZATION ESTIMATION OF ATRIAL FIBRILLATION
SN - 978-989-674-018-4
AU - Alcaraz R.
AU - Joaquín Rieta J.
PY - 2010
SP - 393
EP - 396
DO - 10.5220/0002692103930396