A portable system for non-invasive cardiovascular monitoring in older adults: design and validation

The healthcare system is experiencing profound change, driven by two key factors: the progressive aging of the population and the growing pressure from the increased demand for care. In this context, portable devices play a crucial role in enabling remote monitoring, particularly for older adults. Many portable devices have already been proposed in the literature and introduced to the market. Unfortunately, they all have shortcomings: either they require multiple devices and complex configurations, or they lack clear visual or auditory feedback. This paper, therefore, presents an innovative, non-invasive, user-friendly technological solution for monitoring cardiovascular health. In particular, the device integrates high-sensitivity sensors that allow simultaneous acquisition of photoplethysmographic (PPG) and electrocardiographic (ECG) signals through direct finger contact for 30 s, allowing the extraction of fundamental electrocardiographic parameters (PR, QRS, QT, RR, HR), oxygen saturation (SpO2) and second derivative photoplethysmography indices SDPTG (b/a, c/a, d/a, e/a, SDPTG-AI). The system was validated on an initial cohort of 40 participants (22 women and 18 men; age: 62 ± 11.62 years) by comparing its performance with that of standard medical-grade instrumentation. The system showed good agreement with reference measurements for QRS duration, RR interval, and heart rate, but the PR interval showed greater variability, likely due to difficulties in detecting the P wave. The results concerning SpO2were also consistent with those obtained using the standard reference instrumentation. Moreover, the analysis of SDPTG indices suggests that the device could also serve as a screening tool for vascular health. Future work will aim to enhance real-time connectivity, improve P-wave detection accuracy, and validate the device in a larger population.