A novel parameter from PPG dicrotic notch for estimation of systolic blood pressure using pulse transit time

This paper proposes a new calibration parameter from the dicrotic notch of photoplethysmography (PPG) waveform for systolic blood pressure (SBP) estimation using pulse transit time (PTT). An experiment including exercise was conducted on twelve subjects. The results show that estimation with PTT and a new parameter, i.e. the Relative Amplitude of Secondary peak (RAS), can predict SBP within 1.7 plusmn 6.8 mmHg of the reference for all the subjects before and after exercise (including within 5 minutes and 20-40 minutes after exercise). The underestimated bias after exercise if PTT was used alone can be largely reduced when RAS is introduced. The preliminary analysis indicates that RAS is a promising parameter for calibrating the PTT-based approach for cuffless BP estimation.