A New Algorithm for Measuring Pulse Transit Time from ECG and PPG Signals

Pulse transit Time (PTT) is a physiological parameter that is based on characteristics of the
pulse waveform, a direct indicator of Cardiovascular Diseases (CVD). The (PTT) is defined as
the time taken for the arterial pulse to travel from the heart to a peripheral site. It is commonly
derived from Electrocardiogram (ECG) and Photoplethysmogram (PPG) signal calculations
and is calculated as the interval between the peak of the electrocardiogram (ECG) R-wave and
a time point on the photoplethysmogram (PPG). In this study, we propose a new and lowcomplexity algorithm for the Pulse transit time (PTT) measurement, using these two signals and
detecting (PTT- foot) and (PTT- peak). We built a 37 subjects dataset containing a simultaneous
recording of the (ECG) and (PPG). The calculation of (PTT) consists of detecting the peak and
foot points of a (PPG) and the R-peak of the (ECG) signal. Intermediate operations such as
normalization and thresholding to detect the local maxima and minima, are processed on noisy
signals, this algorithm is improved by a windowing temporal analysis. The obtained results are
promising for the first step. The average sensitivity (SEN) and accuracy (ACC) obtained were
(97.5%, and 96.82%) respectively for R-peaks detection and respectively (97.77%, and 97.64%)
for (PPG-peak) detection. The sensitivity (SEN) and accuracy (ACC) of (PPG- foot) detection
were (98.33%, and 94.14%).