Photoplethysmography for Heart Rate and Rhythm Monitoring: Current Evidence and Clinical Applications

Area of Science:

• Cardiovascular Physiology
• Biomedical Engineering
• Optical Sensing

Background:

• Photoplethysmography (PPG) is a noninvasive optical technique for assessing cardiovascular physiology.
• PPG is integrated into consumer wearables for continuous monitoring of heart rate and rhythm.
• Electrocardiography (ECG) is the gold standard for arrhythmia diagnosis, but PPG presents a scalable alternative.

Purpose of the Study:

• To evaluate the efficacy of PPG in cardiovascular monitoring and arrhythmia detection.
• To compare PPG performance with ECG for heart rate and rhythm assessment.
• To explore the clinical utility and future potential of PPG in patient-centered cardiovascular care.

Main Methods:

• Analysis of PPG signal components (pulsatile and baseline) reflecting arterial blood flow and static tissues.
• Correlation of PPG-derived metrics with ECG-derived heart rate and heart rate variability.
• Assessment of PPG accuracy for heart rate measurement and atrial fibrillation detection, considering factors like motion artifacts and skin tone.

Main Results:

• PPG accurately measures heart rate and shows high sensitivity and specificity for detecting atrial fibrillation.
• PPG performance can be influenced by motion artifacts, skin tone, and signal amplitude at high heart rates.
• ECG confirmation is still necessary for definitive arrhythmia diagnosis due to PPG limitations.

Conclusions:

• PPG is a valuable adjunct to ECG for cardiovascular monitoring, screening, and remote patient care.
• Further standardization and validation protocols are needed for broader clinical adoption of PPG.
• Future developments in PPG include enhanced arrhythmia detection, machine learning integration, and contactless monitoring.