Development of a Finger-Ring-Shaped Hybrid Smart Stethoscope for Automatic S1 and S2 Heart Sound Identification

Area of Science:

• Biomedical Engineering
• Cardiovascular Diagnostics
• Wearable Technology

Background:

• Cardiac auscultation is a common diagnostic method but is limited by visceral sound interference and requires experienced clinicians.
• Improving the accuracy and accessibility of cardiac auscultation is crucial for remote and non-expert use.

Purpose of the Study:

• To develop a hybrid-type personal smart stethoscope with automatic heart sound analysis capabilities.
• To enable non-medical staff to perform cardiac auscultation accurately anywhere, anytime.

Main Methods:

• A folding finger-ring shaped device was designed to simultaneously measure photoplethysmogram (PPG) and phonocardiogram (PCG) signals.
• An advanced Shannon entropy envelope was used for preprocessing to detect heart sound variations and PPG signal peaks.
• An algorithm was developed to analyze the time interval between S1 and S2 heart sounds and PPG peaks.

Main Results:

• The prototype device successfully collected heart sounds (PCG) and PPG signals in young adults.
• The smart stethoscope demonstrated accuracy in detecting heart sound start-points comparable to professional systems.
• The algorithm achieved high accuracy in the automatic identification of S1 and S2 heart sounds.

Conclusions:

• The proposed smart stethoscope offers a promising solution for accurate and accessible cardiac auscultation.
• The device's automatic analysis function can empower non-medical personnel to conduct reliable cardiovascular assessments.
• This technology has the potential to enhance remote patient monitoring and preliminary cardiac diagnostics.