Facile Optical Interrogation for Random Pulse Measurement: Characterization and Analysis of PPG Waveforms Using a...

Area of Science:

• Biomedical Engineering
• Cardiovascular Physiology

Background:

• Noninvasive monitoring of cardiovascular health is crucial for early disease detection.
• Photoplethysmography (PPG) offers a promising, noninvasive method for assessing vascular dynamics.
• Existing PPG devices may lack compactness or real-time waveform analysis capabilities.

Purpose of the Study:

• To develop and evaluate a compact reflection-mode optical sensor for noninvasive pulse waveform measurement.
• To assess the sensor's ability to acquire real-time PPG signals across diverse populations.
• To investigate the sensor's utility in identifying physiological differences related to vascular health.

Main Methods:

• Development of a compact reflection-mode optical sensor integrating an infrared light-emitting diode and photodetector.
• Real-time acquisition of PPG signals from a cohort of subjects.
• Analysis of pulse waveform parameters including systolic amplitude, pulse width, and augmentation index.
• Comparison of waveform morphology between subjects with and without identified health issues.

Main Results:

• The developed sensor successfully acquired real-time PPG signals.
• Physiologically relevant differences in pulse waveforms were reliably detected.
• Average systolic amplitude was 105.06 mV, mean pulse width was 0.14 s, and augmentation index was 0.19.
• Subjects with health issues exhibited trends toward higher augmentation index and reduced pulse waveform compliance, suggesting diminished vascular elasticity.

Conclusions:

• The compact reflection-mode PPG sensor is a viable tool for noninvasive pulse waveform measurement.
• The sensor demonstrates potential for early cardiovascular screening and personalized health monitoring.
• Further validation in larger cohorts and real-world applications is warranted.