Limits...
Fractal Analysis and Hurst Parameter for Intrapartum Fetal Heart Rate Variability Analysis: A Versatile Alternative to Frequency Bands and LF/HF Ratio.

Doret M, Spilka J, Chudáček V, Gonçalves P, Abry P - PLoS ONE (2015)

Bottom Line: Frequency band-based LF/HF ratio and Hurst parameter.This parameter preserves the intuition of a power frequency balance, while avoiding the frequency band splitting procedure and thus the arbitrary choice of a frequency separating bands.The Hurst parameter provides a robust and versatile tool for quantifying FHR variability, yields better acidosis detection performance compared to the LF/HF ratio, and avoids arbitrariness in spectral band splitting and definitions.

View Article: PubMed Central - PubMed

Affiliation: Department of Obstetrics and Gynaecology, Hospices Civils de Lyon, Hôpital Femme-Mère-Enfant, Bron, France.

ABSTRACT

Background: The fetal heart rate (FHR) is commonly monitored during labor to detect early fetal acidosis. FHR variability is traditionally investigated using Fourier transform, often with adult predefined frequency band powers and the corresponding LF/HF ratio. However, fetal conditions differ from adults and modify spectrum repartition along frequencies.

Aims: This study questions the arbitrariness definition and relevance of the frequency band splitting procedure, and thus of the calculation of the underlying LF/HF ratio, as efficient tools for characterizing intrapartum FHR variability.

Study design: The last 30 minutes before delivery of the intrapartum FHR were analyzed.

Subjects: Case-control study. A total of 45 singletons divided into two groups based on umbilical cord arterial pH: the Index group with pH ≤ 7.05 (n = 15) and Control group with pH > 7.05 (n = 30).

Outcome measures: Frequency band-based LF/HF ratio and Hurst parameter.

Results: This study shows that the intrapartum FHR is characterized by fractal temporal dynamics and promotes the Hurst parameter as a potential marker of fetal acidosis. This parameter preserves the intuition of a power frequency balance, while avoiding the frequency band splitting procedure and thus the arbitrary choice of a frequency separating bands. The study also shows that extending the frequency range covered by the adult-based bands to higher and lower frequencies permits the Hurst parameter to achieve better performance for identifying fetal acidosis.

Conclusions: The Hurst parameter provides a robust and versatile tool for quantifying FHR variability, yields better acidosis detection performance compared to the LF/HF ratio, and avoids arbitrariness in spectral band splitting and definitions.

No MeSH data available.


Related in: MedlinePlus

Wavelet and Fourier LF/HF ratios.The LF/HF ratio measured classically using spectral analysis is compared against the LF/HF ratio computed a posteriori using Eq (5) with the Hurst exponent , estimated via the wavelet spectrum. The very satisfactory match between both LH/HF ratios is a strong evidence indicating a power-law shaped decay of the PSD of intrapartum fetal HRV time series.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4556442&req=5

pone.0136661.g005: Wavelet and Fourier LF/HF ratios.The LF/HF ratio measured classically using spectral analysis is compared against the LF/HF ratio computed a posteriori using Eq (5) with the Hurst exponent , estimated via the wavelet spectrum. The very satisfactory match between both LH/HF ratios is a strong evidence indicating a power-law shaped decay of the PSD of intrapartum fetal HRV time series.

Mentions: In addition, in Fig 5, the LF/HF0.15, measured with spectral analysis and the band splitting procedure, is plotted against LF/HF0.15 that was computed a posteriori by plugging into Eq (5) above: For both groups, the match was satisfactory (with correlation coefficients of 0.69 for the Control group and 0.85 for the Index group). This is clear and strong empirical evidence supporting the claim that intrapartum fetal BpM PSD was satisfactorily modeled by a power-law behavior, as in Eq (1) above, at least within the following range of frequencies: fmin = 0.04 ≤ f ≤ fmax = 0.4.


Fractal Analysis and Hurst Parameter for Intrapartum Fetal Heart Rate Variability Analysis: A Versatile Alternative to Frequency Bands and LF/HF Ratio.

Doret M, Spilka J, Chudáček V, Gonçalves P, Abry P - PLoS ONE (2015)

Wavelet and Fourier LF/HF ratios.The LF/HF ratio measured classically using spectral analysis is compared against the LF/HF ratio computed a posteriori using Eq (5) with the Hurst exponent , estimated via the wavelet spectrum. The very satisfactory match between both LH/HF ratios is a strong evidence indicating a power-law shaped decay of the PSD of intrapartum fetal HRV time series.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4556442&req=5

pone.0136661.g005: Wavelet and Fourier LF/HF ratios.The LF/HF ratio measured classically using spectral analysis is compared against the LF/HF ratio computed a posteriori using Eq (5) with the Hurst exponent , estimated via the wavelet spectrum. The very satisfactory match between both LH/HF ratios is a strong evidence indicating a power-law shaped decay of the PSD of intrapartum fetal HRV time series.
Mentions: In addition, in Fig 5, the LF/HF0.15, measured with spectral analysis and the band splitting procedure, is plotted against LF/HF0.15 that was computed a posteriori by plugging into Eq (5) above: For both groups, the match was satisfactory (with correlation coefficients of 0.69 for the Control group and 0.85 for the Index group). This is clear and strong empirical evidence supporting the claim that intrapartum fetal BpM PSD was satisfactorily modeled by a power-law behavior, as in Eq (1) above, at least within the following range of frequencies: fmin = 0.04 ≤ f ≤ fmax = 0.4.

Bottom Line: Frequency band-based LF/HF ratio and Hurst parameter.This parameter preserves the intuition of a power frequency balance, while avoiding the frequency band splitting procedure and thus the arbitrary choice of a frequency separating bands.The Hurst parameter provides a robust and versatile tool for quantifying FHR variability, yields better acidosis detection performance compared to the LF/HF ratio, and avoids arbitrariness in spectral band splitting and definitions.

View Article: PubMed Central - PubMed

Affiliation: Department of Obstetrics and Gynaecology, Hospices Civils de Lyon, Hôpital Femme-Mère-Enfant, Bron, France.

ABSTRACT

Background: The fetal heart rate (FHR) is commonly monitored during labor to detect early fetal acidosis. FHR variability is traditionally investigated using Fourier transform, often with adult predefined frequency band powers and the corresponding LF/HF ratio. However, fetal conditions differ from adults and modify spectrum repartition along frequencies.

Aims: This study questions the arbitrariness definition and relevance of the frequency band splitting procedure, and thus of the calculation of the underlying LF/HF ratio, as efficient tools for characterizing intrapartum FHR variability.

Study design: The last 30 minutes before delivery of the intrapartum FHR were analyzed.

Subjects: Case-control study. A total of 45 singletons divided into two groups based on umbilical cord arterial pH: the Index group with pH ≤ 7.05 (n = 15) and Control group with pH > 7.05 (n = 30).

Outcome measures: Frequency band-based LF/HF ratio and Hurst parameter.

Results: This study shows that the intrapartum FHR is characterized by fractal temporal dynamics and promotes the Hurst parameter as a potential marker of fetal acidosis. This parameter preserves the intuition of a power frequency balance, while avoiding the frequency band splitting procedure and thus the arbitrary choice of a frequency separating bands. The study also shows that extending the frequency range covered by the adult-based bands to higher and lower frequencies permits the Hurst parameter to achieve better performance for identifying fetal acidosis.

Conclusions: The Hurst parameter provides a robust and versatile tool for quantifying FHR variability, yields better acidosis detection performance compared to the LF/HF ratio, and avoids arbitrariness in spectral band splitting and definitions.

No MeSH data available.


Related in: MedlinePlus