A New True Wireless System for Real-Time Pulse Wave Velocity Assessment

This work introduces a novel wireless sensor for clinical pulse wave velocity (PWV) assessment. Two pen-shaped acquisition probes have been designed to incorporate a custom printed circuit board (PCB), a rechargeable battery, and a commercial piezoresistive load cell as the sensing element. Using the Bluetooth low-energy (BLE) 5.2 communication protocol, each probe transmits collected data to the USB dongle integrated into the receiving station realized for this application. A graphical user interface (GUI) has been designed to provide clinicians with real-time PWV values and feedback regarding the quality of the acquired signal. To assess the correct behavior of all system units, extensive validation of the developed firmware routines for data transfer and handling was conducted. The reliability of the PWV estimation was assessed in a preclinical study against the gold-standard device for noninvasive PWV (SphygmoCor), showing a robust linear correlation yielding a value of
${R}^{{2}} =0.89$
. The Bland-Altman plot computed with respect to the reference system reports a mean difference equal to
$- 0.65~\pm ~0.41$
m/s. Finally, electromagnetic compatibility and clinical usability tests were conducted to determine the device’s precompliance, according to the clinical safety rules and guidelines described in the IEC-60601 standard for medical devices.