An unobtrusive PEP estimation method using hand-to-hand impedance plethysmography

Area of Science:

• Biomedical Engineering
• Cardiovascular Physiology
• Wearable Technology

Background:

• Cuffless blood pressure (CBP) estimation using pulse transit time (PTT) is of significant interest for wearables.
• Pulse arrival time (PAT) measurements, common in wearables, include pre-ejection period (PEP), limiting accuracy.
• Traditional PEP measurement requires specialized equipment and trained personnel, hindering out-of-hospital use.

Purpose of the Study:

• To introduce an unobtrusive hand-to-hand impedance plethysmography (hh-IPG) method for estimating the pre-ejection period (PEP).
• To validate the feasibility and accuracy of hh-IPG for PEP estimation compared to established methods.
• To explore the potential of hh-IPG for integration into convenient, non-invasive wearable devices.

Main Methods:

• Sequential recording of hand-to-hand impedance plethysmography (hh-IPG) and reference impedance cardiography (ICG) signals.
• Data acquisition from 9 subjects across a wide age range for 2 minutes each.
• Correlation analysis between PEP estimates derived from hh-IPG and ICG.

Main Results:

• A strong correlation (R = 0.90) was observed between PEP estimated using hh-IPG and reference PEP from ICG.
• The hh-IPG method demonstrated feasibility for PEP estimation.
• The results suggest potential for incorporating hh-IPG into future wearable devices.

Conclusions:

• The hh-IPG method provides a non-invasive, stable, and user-friendly alternative for PEP estimation.
• This approach offers lower variability compared to traditional impedance cardiography (ICG).
• hh-IPG is suitable for application in wearable devices and telemedicine platforms for enhanced cardiovascular monitoring.