Title: Evaluation of the effect of posture on carotid-to-toe pulse transit time values estimated using system identification
Authors: Aws Zuhair Sameen; Rosmina Jaafar; Edmond Zahedi
Addresses: Department of Electrical, Electronic and Systems, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia (UKM), Bangi 43600, Selangor, Malaysia ' Department of Electrical, Electronic and Systems, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia (UKM), Bangi 43600, Selangor, Malaysia ' Department of Electrical and Computer Engineering, School of Energy, British Columbia Institute of Technology, Burnaby Campus, Canada
Abstract: Pulse transit time (PTT) is defined as the time a pulse wave needs to travel from one point of the blood circulation to another point. Monitoring PTT values of a person is useful in non-invasive, cuff-less estimation of blood pressure measurement. In this paper, PTT values estimated from two PPG signals from the reflective photoplethysmography of carotid and toe that are collected from 12 healthy subjects (eight males and four females) age 23.8 ± 1.5 years. PTT has been estimated using an auto-regressive (ARX) model. PTT values were estimated for all subjects in three different positions; sit, stand and supine. Results show that the PTT in sit and stand positions are statistically no different (84.5 ± 19.6 ms versus 78 ± 15.9 ms, p = 0.44). However, the PTT in the supine position is significantly higher than the two other positions (145.7 ± 18.4 ms versus 84.5 ± 19.6 ms and 145.7 ± 18.4 ms versus 78 ± 15.9 ms respectively, p < 0.01 for both situations).
Keywords: pulse transit time; PTT; system identification; photoplethysmogram; PPG; ARX model; time delay estimation; posture; biosignals; auto-regressive system; pulse sensor; PPG waveform.
DOI: 10.1504/IJBET.2019.101050
International Journal of Biomedical Engineering and Technology, 2019 Vol.31 No.1, pp.35 - 46
Received: 04 Nov 2016
Accepted: 01 Feb 2017
Published online: 23 Jul 2019 *