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Updated: May 25, 2026

Semi-automated Optical Heartbeat Analysis of Small Hearts
Published on: September 16, 2009
Noise detection in heart sound recordings
Mohammad K Zia1, Benjamin Griffel, Vladimir Fridman
1University of Medicine and Dentistry of New Jersey – Graduate School of Biomedical Sciences and Rutgers, the State University of New Jersey, Piscataway, NJ, USA. mkhawarzia@gmail.com
Insights
This study introduces a new noninvasive acoustic method to detect coronary artery disease (CAD) early. The technique effectively filters out clinical noise, improving the detection of faint sounds from narrowed arteries.
Area of Science:
- Cardiology
- Biomedical Engineering
- Acoustic Signal Processing
Background:
- Coronary artery disease (CAD) is a leading cause of mortality, often detected late.
- Current diagnostic methods for CAD are invasive, costly, and unsuitable for early screening.
- Early detection of CAD is crucial for timely intervention and improved patient outcomes.
Purpose of the Study:
- To develop a noninvasive and cost-effective acoustic system for early CAD detection.
- To address the challenge of clinical noise interfering with faint acoustic signals from narrowed coronary arteries.
- To propose and validate a novel noise detection and elimination method for acoustic CAD diagnosis.
Main Methods:
- Utilizing an acoustic approach to identify sounds generated by turbulent blood flow in narrowed coronary arteries.
- Implementing a reference channel-based method for detecting and eliminating ambient clinical noise.
- Evaluating the effectiveness of the proposed noise reduction technique in preserving faint CAD-related acoustic signals.
Main Results:
- The developed acoustic method shows promise for noninvasive CAD detection.
- The proposed noise detection and elimination technique effectively mitigates interference from clinical noise.
- Successful identification of noise is demonstrated as critical for the acoustic approach's viability.
Conclusions:
- A noninvasive acoustic system using noise reduction shows potential for early coronary artery disease screening.
- The developed noise cancellation method is essential for the success of the acoustic CAD detection approach.
- This technology could offer a cost-effective and accessible alternative to current invasive diagnostic tools.
Abstract:
Coronary artery disease (CAD) is the leading cause of death in the United States. Although progression of CAD can be controlled using drugs and diet, it is usually detected in advanced stages when invasive treatment is required. Current methods to detect CAD are invasive and/or costly, hence not suitable as a regular screening tool to detect CAD in early stages. Currently, we are developing a noninvasive and cost-effective system to detect CAD using the acoustic approach. This method identifies sounds generated by turbulent flow through partially narrowed coronary arteries to detect CAD. The limiting factor of this method is sensitivity to noises commonly encountered in the clinical setting. Because the CAD sounds are faint, these noises can easily obscure the CAD sounds and make detection impossible. In this paper, we propose a method to detect and eliminate noise encountered in the clinical setting using a reference channel. We show that our method is effective in detecting noise, which is essential to the success of the acoustic approach.
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