Skin-Coupled Personal Wearable Ambulatory Pulse Wave Velocity Monitoring System Using Microelectromechanical Sensors

A prototype skin-coupled personal wearable ambulatory pulse wave velocity (PWV) monitoring system is proposed and demonstrated. The system employs two packaged silicone-coated microelectromechanical systems (MEMS) pressure sensors for detecting blood pressure waveforms through skin surface contact in a non-invasive and continuous manner. The sensors are placed at two adjacent measurement points of the body, for example, the wrist or the neck, to measure blood pressure waveforms simultaneously. The measured waveforms are recorded by a data acquisition unit for signal processing and analysis. Analyzing the two waveforms can obtain the delay time between them, thus determining the local PWV. An application-specific signal processing algorithm is developed to accurately obtain the PWV. The PWV and detailed blood pressure waveforms are critical for monitoring human health condition. The prototype personal wearable monitoring system demonstrated its capability of detecting PWV of approximately 5.3 m/s at the wrist and 5.1 m/s at the neck from a volunteer. Similar tests were performed on two additional volunteers, obtaining PWV of 5.9 and 6.7 m/s, respectively, measured at the wrist.