Continuous Beat-to-Beat Cuffless Blood Pressure Monitoring Using Wearable Radial Artery Tonometry

Area of Science:

• Biomedical Engineering
• Cardiovascular Physiology
• Wearable Technology

Background:

• Continuous blood pressure (BP) monitoring is crucial for managing cardiovascular health.
• Current methods often rely on intermittent cuff-based measurements, limiting real-time data acquisition.
• Noninvasive, cuffless BP monitoring technologies are needed for improved patient care and research.

Purpose of the Study:

• To assess the feasibility of continuous beat-to-beat BP monitoring using radial artery tonometry.
• To evaluate the reliability of this method under controlled dynamic physiological conditions in healthy adults.

Main Methods:

• Twenty healthy adults underwent laboratory recordings including rest and dynamic challenges (isometric handgrip, cold pressor, inspiratory loading).
• Beat-to-beat BP was derived from radial artery tonometry waveforms, with drift correction and signal quality filtering.
• Tonometric BP measurements were validated against a Finapres continuous noninvasive reference device.

Main Results:

• Fourteen recordings met stability criteria, retaining over 94% of data.
• Strong agreement was observed between tonometric BP and the reference device (Pearson correlations: 0.933 for SBP, 0.945 for DBP, 0.954 for MAP).
• Mean absolute differences were low: 7.1 ± 5.7 mmHg (SBP), 2.5 ± 2.5 mmHg (DBP), 3.8 ± 3.0 mmHg (MAP).

Conclusions:

• Radial artery tonometry, with drift correction and quality filtering, reliably tracks beat-to-beat BP during dynamic conditions.
• This supports the feasibility of wearable, cuffless radial artery tonometry for continuous BP monitoring.
• The study provides a foundation for evaluating long-term tonometric BP recordings under physiological stress.