A Four-Channel Heart-Sound Acquisition and Denoising System Based on ECG-Scale andPneumatic Control
Jiang Houqi1#, Zhang Chi1#* , She Jin2#, Li Deyu1#
1(School of Biological Science and Medical Engineering, Beihang University;National Medical Innovation Platform for Industry-Education Integration in Advanced Medical Devices (Interdiscipline of Medicine and Engineering); Key Laboratory of Innovation andTransformation of Advanced Medical Devices, Ministry of Industry and Information Technology; State Key Laboratory of Virtual Reality Technology and Systems, Beijing 100191, China) 2(Medical Engineering Department, Yichang Central People's Hospital, the First Clinical Medical Science College of China Three Gorges University, Yichang 443003, Hubei,China)
Abstract：Cardiovascular diseases pose a significant threat to the health of Chinese residents. Multi-channel electronic auscultation equipment can provide important information for cardiovascular disease screening and is currently a research hotspot; however, there are issues such asredundant sensors, low stability, and poor portability. This study aims to design a wearable multi-channel heart sound acquisition system to overcome the limitations of traditional equipment in stability, portability, and signal quality, providing technical support for early screening and long-term monitoring of cardiovascular diseases. The proposed multi-channel heart sound acquisition system in this paper adopted a vest-like design. A piezoelectric sensor CM-01B was used as the heart sound acquisition sensor, which is embedded in a gel and integrated into the vest to ensure stable contact between the sensor and the human surface. An air pressure control system was used to automatically inflate the airbag through closed-loop control to ensure that the sensor was uniformly pressed on the acquisition site, improving the stability of signal acquisition.Using the signals collected byan electronic stethoscope(ETZ-1A) as a reference, the frequency domain similarity was used to evaluate four heart sound sites, four lung sound sites, and their combinations, showing that the optimal acquisition sites for heart sounds included aortic valve, mitral valve, upper part of the right sternoclavicular line, and lower part of the left axillary anterior line. This paper proposed a heart sound denoising algorithm -ECG-guided cardiac sound denoising via DTW-PCA template matching algorithm (EDPT), which introduced single-lead electrocardiogram signals to provide an electrocardiogram scale for heart sound denoising; using electrocardiogram signals to segment the cardiac cycle and extract standard heart sound templates for matching filtering to achieve separation and denoising of heart sounds; and evaluating the effect of the EDPT algorithm using signal-to-noise ratio.A total of 16 healthy adult subjects (8 males and 8 females) were recruited for experimental validation. After introducing the electrocardiographic scale, the mean signal-to-noise ratio (SNR) of the separated heart sounds obtained by the EDPT algorithm increased from (18.09±0.50)dB to(29.69±1.49)dB. Pairedt-test analysis demonstrated that the separation performance of the EDPT algorithm was significantly superior to that of the conventional ICA algorithm (P<0.001). These results indicate that the EDPT-based heart sound denoising algorithm developed in this study can more effectively separate heart sound signals, thereby validating both the effectiveness of the algorithm and the feasibility of the proposed system. The multi-channel heart sound acquisition system developed in this study, by introducing the electrocardiogram scale and air pressure control technology, combined with the EDPT heart sound denoising algorithm, significantly improved the stability and signal quality of heart sound acquisition. This system can provide technical support for cardiovascular disease screening based on auscultation and may also be extended to other auscultation fields such as lung sound auscultation in the future.
姜厚琦, 张弛, 佘瑾, 李德玉. 基于心电标尺与气压控制的四通道心音采集与去噪系统[J]. 中国生物医学工程学报, 2026, 45(2): 188-198.
Jiang Houqi, Zhang Chi, She Jin, Li Deyu. A Four-Channel Heart-Sound Acquisition and Denoising System Based on ECG-Scale andPneumatic Control. Chinese Journal of Biomedical Engineering, 2026, 45(2): 188-198.
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