Innovative Wearable Platform for Synchronized Biosignals Acquisition: A Proof of Concept in a Cuff-Less Blood Pressure Monitoring Case Study

Objective: This study evaluates the performance of a fully wireless multi-node wearable platform equipped with a sub-microsecond synchronization engine in a clinically relevant scenario. The prototype system is used in a cuff-less blood pressure monitoring application, based on pulse arrival time derived from synchronized ECG and PPG signals. Methods: The system integrates a custom 2.4 GHz synchronization protocol and Bluetooth Low Energy for data transmission. Nineteen healthy subjects completed a treadmill protocol designed to induce transient hemodynamic perturbations representative of daily-life physical activities. PAT values extracted from ECG and PPG signals acquired before and after exercise were compared with reference systolic blood pressure (SBP) measurements, intermittently sampled using a validated oscillometric device. The experimental protocol and analysis were designed to reflect realistic home monitoring scenarios, including limited user interaction during measurements. Results: Immediately after exercise, significant deviations from baseline were observed in computed PAT (p< 10-18) and SBP (p< 10-7). PAT recovery trend was accurately modeled by a mono-exponential function (R2=0.98). Recovery indices derived from PAT and SBP were strongly correlated (Pearson's r=0.93, p< 0.001) with high concordance (ρ c=0.885), although Bland-Altman analysis revealed subject-specific variability (LoA: -34.36% / 37.53%). Conclusion: The proposed platform enables continuous synchronized multi-signal acquisition for extracting PAT dynamics and tracking blood pressure fluctuations under realistic home-monitoring conditions, with minimal additional user interaction. These results support the operational feasibility of wirelessly synchronized architectures for cardiovascular monitoring in daily-life scenarios, promoting integration into remote health assessment workflows beyond traditional intermittent cuff-based measurements.