A new two-pulse synthesis model for digital volume pulse signal analysis.

Analysis of digital volume pulse (DVP) signal measured by photoplethysmograph (PPG) technique is a low cost non-invasive method of obtaining vital information related to arterial conditions. In this paper, we present a new two-pulse synthesis (TPS) model for deriving arterial parameters, useful for noninvasive assessment of human vascular health. The model is based on the use of Rayleigh function. Relevance of the proposed model is established by applying it on a sample set of 113 PPG signals, obtained form healthy and treated hypertensive subjects. The TPS model compares well with the conventional methods in determining parameters such as pulse transit time or foot-to-foot delay (D), reflection index (RI), stiffness index (SI) and pulse wave velocity (PWV). A new parameter, viz. differential pulse spread (DPS) has also been introduced for DVP signals using the model. The differential pulse spread provides a new dimension to estimate the process of arterial degeneration.