Feasibility of pulse rate variability as feedback in closed-loop percutaneous auricular vagus nerve stimulation

Elena Schrödl1 , Stefan Kampusch2 , Babak Dabiri Razlighi3 , Van Hoang Le4 , Jozsef Constantin Széles5 , Eugenijus Kaniusas6

1, 2, 3, 4, 6Institute of Electrodynamics, Microwave and Circuit Engineering, Vienna University of Technology, Vienna, Austria

5Department of Surgery, Medical University of Vienna, Vienna, Austria

1Corresponding author

Vibroengineering PROCEDIA, Vol. 26, 2019, p. 35-39. https://doi.org/10.21595/vp.2019.20949
Received 12 August 2019; accepted 19 August 2019; published 26 September 2019

Copyright © 2019 Elena Schrödl, et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Creative Commons License

Percutaneous auricular vagus nerve stimulation (pVNS) is a novel approach of treating cardiovascular and inflammatory diseases, as well as pain and neurological conditions. The treatment can be optimized by using biosignals as objective measures and feedback-control. One suitable biofeedback could be the use of pulse rate and pulse rate variability (PRV) derived from optical pulse plethysmography (PPG) instead of heart rate and heart rate variability (HRV) derived from electrocardiogram (ECG). For this purpose, a single-lead ECG on the thorax and a PPG on the earlobe were measured simultaneously on 10 healthy subjects for 420 s during three different respiratory phases. The data was analyzed and compared with scatterplots, the Pearson correlation coefficient and a Bland-Altman analysis. The outcomes show a very high correlation of heart rates from PPG and ECG (ri= 0.9663) and SDNN values (rsdnn= 0.9791). Comparison of RMSSD values showed a high positive correlation (rrmssd= 0.7963) but a mean overestimation of 10 ms in RMSSD values measured with the PPG. The results presented suggest that PRV could be and alternative biofeedback used in pVNS.

Keywords: vagus nerve stimulation, heart rate variability, pulse rate variability.


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