A Multichannel Real-Time Bioimpedance Measurement Device for Pulse Wave Analysis

Area of Science:

• Biomedical Engineering
• Cardiovascular Physiology

Background:

• Pulse wave analysis (PWA) is crucial for cardiovascular assessment.
• Traditional PWA relies on invasive pressure sensors.
• Bioimpedance offers a non-invasive method to detect pulse wave-induced conductivity changes.

Purpose of the Study:

• To develop and validate a microcontroller-based bioimpedance measurement system for PWA.
• To enable simultaneous, high-resolution impedance measurements from multiple channels.
• To demonstrate the system's capability in analyzing pulse wave morphology and velocity.

Main Methods:

• A microcontroller-based system with a 24-bit analog-to-digital converter was designed.
• The system acquires up to 1000 impedance measurements per second per channel.
• Data is transferred via USB to a PC with a real-time graphical user interface for filtering and plotting.

Main Results:

• The system achieved a high signal-to-noise ratio (92-96 dB) for impedance measurements.
• Performance was validated for constant impedances and time-varying impedance changes.
• Successful demonstration of pulse wave analysis, including morphology and aortic pulse wave velocity, in human subjects.

Conclusions:

• The developed bioimpedance system provides a viable, non-invasive approach for PWA.
• The multichannel capability and high data acquisition rate support detailed cardiovascular analysis.
• This technology has potential applications in cardiovascular health monitoring and diagnostics.