Denoising RF defibrillator waveforms for intracardiac atrial substrate impedance characterisation using digital filtering techniques

OJ Escalona, PR Walsh, AS Rababah, V Kodoth, G Manoharan

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

Intra-cardiac impedance (ICI) is one of the major determinants of success during internal cardioversion of atrial fibrillation(AF) and is consequently of significant importance in the development of more effective cardioversion therapies. In this study, the voltage and current waveform delivered during internal cardioversion of patients with persistent AF treated using a novel low-tilt rectilinear waveform (generated by a radiofrequency (RF) defibrillator) and following a step up energy protocol (50V-300V in 50V steps) were recorded. However, within the clinical environment these waveforms are typically compromised with electrical noise. The objective of this work was to investigate if it was possible to develop an algorithm, using digital signal processing (DSP)in the MATLAB environment, to denoise the AF defibrillation voltage and current waveforms by applying spectral analysis and digital filtering techniques. Preliminary results indicated that spectral analysis of the processed rectilinear waveform signals allowed estimation of the most appropriate cutoff frequency as 1125Hz-2250Hz. Initial results also indicated that application of a Hanning windowing was more appropriate than Blackman windowing in the spectral preservation of the rectilinear waveform signals. Furthermore, for this particular type of waveform, noise reduction using a 7th order Butterworth filter design was found to be more efficacious than a 200 order FIR digital filter. In conclusion, within this explorative study, the processing algorithm developed was effective for denoising voltage and current signals recorded during cardioversion and therefore provides a useful tool for characterisation of intra-cardiac impedance during cardioversion.
LanguageEnglish
Title of host publicationUnknown Host Publication
Pages1329-1332
Number of pages4
Volume51
DOIs
Publication statusPublished - 30 Oct 2015
EventWorld Congress on Medical Physics and Biomedical Engineering, 2015. - Toronto, Canada
Duration: 30 Oct 2015 → …

Conference

ConferenceWorld Congress on Medical Physics and Biomedical Engineering, 2015.
Period30/10/15 → …

Fingerprint

Defibrillators
Spectrum analysis
Electric potential
Substrates
Butterworth filters
FIR filters
Cutoff frequency
Digital filters
Noise abatement
Digital signal processing
MATLAB
Network protocols
Processing

Keywords

  • Inracardiac impedance
  • atrial fibrillation
  • RF defibrillator
  • low-tilt rectilinear waveforms
  • internal cardioversion
  • denoising
  • digital filter.

Cite this

Escalona, OJ ; Walsh, PR ; Rababah, AS ; Kodoth, V ; Manoharan, G. / Denoising RF defibrillator waveforms for intracardiac atrial substrate impedance characterisation using digital filtering techniques. Unknown Host Publication. Vol. 51 2015. pp. 1329-1332
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title = "Denoising RF defibrillator waveforms for intracardiac atrial substrate impedance characterisation using digital filtering techniques",
abstract = "Intra-cardiac impedance (ICI) is one of the major determinants of success during internal cardioversion of atrial fibrillation(AF) and is consequently of significant importance in the development of more effective cardioversion therapies. In this study, the voltage and current waveform delivered during internal cardioversion of patients with persistent AF treated using a novel low-tilt rectilinear waveform (generated by a radiofrequency (RF) defibrillator) and following a step up energy protocol (50V-300V in 50V steps) were recorded. However, within the clinical environment these waveforms are typically compromised with electrical noise. The objective of this work was to investigate if it was possible to develop an algorithm, using digital signal processing (DSP)in the MATLAB environment, to denoise the AF defibrillation voltage and current waveforms by applying spectral analysis and digital filtering techniques. Preliminary results indicated that spectral analysis of the processed rectilinear waveform signals allowed estimation of the most appropriate cutoff frequency as 1125Hz-2250Hz. Initial results also indicated that application of a Hanning windowing was more appropriate than Blackman windowing in the spectral preservation of the rectilinear waveform signals. Furthermore, for this particular type of waveform, noise reduction using a 7th order Butterworth filter design was found to be more efficacious than a 200 order FIR digital filter. In conclusion, within this explorative study, the processing algorithm developed was effective for denoising voltage and current signals recorded during cardioversion and therefore provides a useful tool for characterisation of intra-cardiac impedance during cardioversion.",
keywords = "Inracardiac impedance, atrial fibrillation, RF defibrillator, low-tilt rectilinear waveforms, internal cardioversion, denoising, digital filter.",
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Escalona, OJ, Walsh, PR, Rababah, AS, Kodoth, V & Manoharan, G 2015, Denoising RF defibrillator waveforms for intracardiac atrial substrate impedance characterisation using digital filtering techniques. in Unknown Host Publication. vol. 51, pp. 1329-1332, World Congress on Medical Physics and Biomedical Engineering, 2015., 30/10/15. https://doi.org/10.1007/978-3-319-19387-8_324

Denoising RF defibrillator waveforms for intracardiac atrial substrate impedance characterisation using digital filtering techniques. / Escalona, OJ; Walsh, PR; Rababah, AS; Kodoth, V; Manoharan, G.

Unknown Host Publication. Vol. 51 2015. p. 1329-1332.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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AU - Escalona, OJ

AU - Walsh, PR

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AU - Manoharan, G

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N2 - Intra-cardiac impedance (ICI) is one of the major determinants of success during internal cardioversion of atrial fibrillation(AF) and is consequently of significant importance in the development of more effective cardioversion therapies. In this study, the voltage and current waveform delivered during internal cardioversion of patients with persistent AF treated using a novel low-tilt rectilinear waveform (generated by a radiofrequency (RF) defibrillator) and following a step up energy protocol (50V-300V in 50V steps) were recorded. However, within the clinical environment these waveforms are typically compromised with electrical noise. The objective of this work was to investigate if it was possible to develop an algorithm, using digital signal processing (DSP)in the MATLAB environment, to denoise the AF defibrillation voltage and current waveforms by applying spectral analysis and digital filtering techniques. Preliminary results indicated that spectral analysis of the processed rectilinear waveform signals allowed estimation of the most appropriate cutoff frequency as 1125Hz-2250Hz. Initial results also indicated that application of a Hanning windowing was more appropriate than Blackman windowing in the spectral preservation of the rectilinear waveform signals. Furthermore, for this particular type of waveform, noise reduction using a 7th order Butterworth filter design was found to be more efficacious than a 200 order FIR digital filter. In conclusion, within this explorative study, the processing algorithm developed was effective for denoising voltage and current signals recorded during cardioversion and therefore provides a useful tool for characterisation of intra-cardiac impedance during cardioversion.

AB - Intra-cardiac impedance (ICI) is one of the major determinants of success during internal cardioversion of atrial fibrillation(AF) and is consequently of significant importance in the development of more effective cardioversion therapies. In this study, the voltage and current waveform delivered during internal cardioversion of patients with persistent AF treated using a novel low-tilt rectilinear waveform (generated by a radiofrequency (RF) defibrillator) and following a step up energy protocol (50V-300V in 50V steps) were recorded. However, within the clinical environment these waveforms are typically compromised with electrical noise. The objective of this work was to investigate if it was possible to develop an algorithm, using digital signal processing (DSP)in the MATLAB environment, to denoise the AF defibrillation voltage and current waveforms by applying spectral analysis and digital filtering techniques. Preliminary results indicated that spectral analysis of the processed rectilinear waveform signals allowed estimation of the most appropriate cutoff frequency as 1125Hz-2250Hz. Initial results also indicated that application of a Hanning windowing was more appropriate than Blackman windowing in the spectral preservation of the rectilinear waveform signals. Furthermore, for this particular type of waveform, noise reduction using a 7th order Butterworth filter design was found to be more efficacious than a 200 order FIR digital filter. In conclusion, within this explorative study, the processing algorithm developed was effective for denoising voltage and current signals recorded during cardioversion and therefore provides a useful tool for characterisation of intra-cardiac impedance during cardioversion.

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UR - http://www.springer.com/gb/book/9783319193861?wt_mc=ThirdParty.SpringerLink.3.EPR653.About_eBook

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