Medical & Biological Engineering & Computing

, Volume 57, Issue 6, pp 1247–1263 | Cite as

Comparison of short-term heart rate variability indexes evaluated through electrocardiographic and continuous blood pressure monitoring

  • Riccardo PerniceEmail author
  • Michal Javorka
  • Jana Krohova
  • Barbora Czippelova
  • Zuzana Turianikova
  • Alessandro Busacca
  • Luca Faes
  • Member, IEEE
Original Article


Heart rate variability (HRV) analysis represents an important tool for the characterization of complex cardiovascular control. HRV indexes are usually calculated from electrocardiographic (ECG) recordings after measuring the time duration between consecutive R peaks, and this is considered the gold standard. An alternative method consists of assessing the pulse rate variability (PRV) from signals acquired through photoplethysmography, a technique also employed for the continuous noninvasive monitoring of blood pressure. In this work, we carry out a thorough analysis and comparison of short-term variability indexes computed from HRV time series obtained from the ECG and from PRV time series obtained from continuous blood pressure (CBP) signals, in order to evaluate the reliability of using CBP-based recordings in place of standard ECG tracks. The analysis has been carried out on short time series (300 beats) of HRV and PRV in 76 subjects studied in different conditions: resting in the supine position, postural stress during 45° head-up tilt, and mental stress during computation of arithmetic test. Nine different indexes have been taken into account, computed in the time domain (mean, variance, root mean square of the successive differences), frequency domain (low-to-high frequency power ratio LF/HF, HF spectral power, and central frequency), and information domain (entropy, conditional entropy, self entropy). Thorough validation has been performed using comparison of the HRV and PRV distributions, robust linear regression, and Bland–Altman plots. Results demonstrate the feasibility of extracting HRV indexes from CBP-based data, showing an overall relatively good agreement of time-, frequency-, and information-domain measures. The agreement decreased during postural and mental arithmetic stress, especially with regard to band-power ratio, conditional, and self-entropy. This finding suggests to use caution in adopting PRV as a surrogate of HRV during stress conditions.


Heart rate variability (HRV) Pulse rate variability (PRV) Electrocardiography (ECG) Photoplethysmography (PPG) Continuous blood pressure (CBP) Time series analysis 



The research has been supported by the grant ASTONISH, H2020-EU. (ECSEL), University of Palermo, and grants APVV-0235-12, VEGA 1/0117/17, VEGA 1/0202/16, and project “Biomedical Center Martin” ITMS code no. 26220220187, the project co-financed from EU sources.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Informed consent

Informed consent was obtained from all individual participants included in the study. All participants signed a written informed consent, and when the subject was a minor (age < 18 years) prior parental or legal guardian permission was gathered to allow the child to participate in the study. All the procedures were approved by the Ethical Committee of the Jessenius Faculty of Medicine, Comenius University, Martin, Slovakia.

Supplementary material

11517_2019_1957_MOESM1_ESM.docx (771 kb)
ESM 1 (DOCX 770 kb)


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Copyright information

© International Federation for Medical and Biological Engineering 2019

Authors and Affiliations

  1. 1.Department of EngineeringUniversity of PalermoPalermoItaly
  2. 2.Department of Physiology and the Biomedical Center Martin, Jessenius Faculty of MedicineComenius University in BratislavaMartinSlovakia

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