Comparison of Different Methods for Estimating Cardiac Timings: A Comprehensive Multimodal Echocardiography...

Area of Science:

• Biomedical Engineering
• Cardiovascular Physiology
• Wearable Technology

Background:

• Cardiac time intervals are crucial hemodynamic indices reflecting left ventricular performance.
• Phonocardiography (PCG), impedance cardiography (ICG), and seismocardiography (SCG) are unobtrusive methods for measuring cardiac timings.
• These methods hold potential for integration into wearable devices for continuous monitoring.

Purpose of the Study:

• To evaluate the accuracy and precision of beat-to-beat cardiac timing extraction using PCG, ICG, and SCG.
• To compare these methods against multimodal echocardiography as the clinical gold standard.
• To assess the suitability of SCG and PCG for wearable applications.

Main Methods:

• Acquired PCG, ICG, and SCG recordings from 86 healthy adults.
• Analyzed a total of 2,120 cardiac cycles.
• Utilized multimodal echocardiography (Doppler, TDI, M-mode) as the reference standard for validation.

Main Results:

• SCG showed 86% accuracy for pre-ejection period (PEP) estimation, compared to 43% for ICG.
• For total systolic time (TST) estimation, SCG achieved 90% accuracy, PCG 80%, and ICG 43%.
• SCG and PCG demonstrated acceptable accuracy and precision in estimating cardiac timings.

Conclusions:

• SCG and PCG are promising non-invasive techniques for assessing cardiac timings.
• These methods offer better accuracy than ICG for key cardiac interval measurements.
• SCG and PCG are suitable for development in wearable cardiac monitoring devices.