Photoplethysmography pulse rate variability as a surrogate measurement of heart rate variability during non-stationary conditions

Abstract

In this paper we assessed the possibility of using the pulse rate variability (PRV) extracted from the photoplethysmography signal as an alternative measurement of the HRV signal in non-stationary conditions. The study is based on analysis of the changes observed during a tilt table test in the heart rate modulation of 17 young subjects. First, the classical indices of HRV analysis were compared to the indices from PRV in intervals where stationarity was assumed. Second, the time-varying spectral properties of both signals were compared by time-frequency (TF) and TF coherence analysis. Third, the effect of replacing PRV with HRV in the assessment of the changes of the autonomic modulation of the heart rate was considered. Time-invariant HRV and PRV indices showed no statistically significant differences (p > 0.05) and high correlation (>0.97). Time-frequency analysis revealed that the TF spectra of both signals were highly correlated (0.99 +/- 0.01); the difference between the instantaneous power, in the LF and HF bands, obtained from HRV and PRV was small (<10(-3) s(-2)) and their temporal patterns were highly correlated (0.98 +/- 0.04 and 0.95 +/- 0.06 in the LF and HF bands, respectively) and TF coherence in the LF and HF bands was high (0.97 +/- 0.04 and 0.89 +/- 0.08, respectively). Finally, the instantaneous power in the LF band was observed to significantly increase during head-up tilt by both HRV and PRV analysis. These results suggest that although some differences in the time-varying spectral indices extracted from HRV and PRV exist, mainly in the HF band associated with respiration, PRV could be used as a surrogate of HRV during non-stationary conditions, at least during the tilt table test.

Correntropy-Based Pulse Rate Variability Analysis in Children with Sleep Disordered Breathing

“…This fact was also reflected by the significant differences found between the same features extracted through both analyses (CSD versus PSD). As reported previously in studies focused on the OSA effect on HRV [5,10,30], both PRV analyses (CSD and PSD) showed higher power in the low frequency band and lower power in the high frequency band in OSA epochs relative to non-OSA epochs. The most significant features were the HFn and LF/HF ratio, reflecting higher sympathetic activity and lower parasympathetic activity during OSA events.…”

Assessment of Time and Frequency Domain Entropies to Detect Sleep Apnoea in Heart Rate Variability Recordings from Men and Women

“…Another limitation is the complexity inherent to the acquisition of surface ECG as a previous step to obtain HRV. Although acquiring ECG is significantly easier than recording the whole set of signals involved during PSG, there exist studies which address the obtaining of HRV from simpler devices such as the oximeter [62,63]. Moreover, regarding the R-R time series, no specific correction for the timing of R waves associated with ectopic beats has been applied in this study.…”

Comparison of foot finding methods for deriving instantaneous pulse rates from photoplethysmographic signals

“…PRV analysis has been performed in multiple studies using PPG signals recorded from the finger or earlobe and report varying levels of accuracy compared to HRV (2,4,5,7,8,15,21). By comparison to ECG signals, PPG waveforms are characteristically smooth and do not contain a clearly defined and detectable 'landmark' feature.…”