Bilateral study on arterial stiffness assessment by a non-invasive optical technique of Photoplethysmography

The great potential of Photoplethysmography (PPG) for vascular assessment, such as arterial disease, arterial compliance and ageing, was recently recognized. In this paper we describe a prototype apparatus based on the low cost, simple and portable PPG technology. Also, we are present a new protocol for the experimental measurements of arterial stiffness as a potential tool for early diagnostic of the atherosclerosis. A bilateral pulse measurements system simultaneously acquired PPG pulses from left and right arms, electrocardiographic (ECG) and pressure electrical signals. The PPG reflectance mode sensors utilize low cost semiconductor technology with LED and photodetector devices working at the near infrared wavelength of 940 nm. The principal parameters of LED sensor and its importance for signal sensitivity optimization are also discussed.