Analysis of Heart Sounds with Wavelet Entropy

  • S. Bunluechokchai
  • P. Tosaranon
Conference paper
Part of the Lecture Notes in Electrical Engineering book series (LNEE, volume 27)


It has been reported that heart sound detection is very useful in the diagnostic process of heart diseases, especially in patients with abnormality of the cardiac valves. Heart sounds originate from blood flow through the cardiac valves during heart contraction and relaxation, and they can be heard and recorded in the patient’s chest. In this study, two groups of patients, those with normal hearts and those with aortic stenosis, were investigated. This paper presents the application of wavelet transform analysis to the heart sound signals of both groups. The continuous wavelet transform plot shows that the patients with aortic stenosis are likely to have irregular patterns of heart sounds in a time-scale representation, whereas normal heart sounds are likely to have relatively smooth surfaces. The wavelet entropy is then applied to the heart sounds. A disordered signal gives a high entropy value. Observations of the preliminary results in this study found that the heart sounds from patients with aortic stenosis tend to have higher wavelet entropy than those from patients with normal hearts.


Aortic Stenosis Normal Heart Heart Sound Continuous Wavelet Transform Cardiac Valve 
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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • S. Bunluechokchai
    • 1
  • P. Tosaranon
  1. 1.Department of Industrial Physics and Medical Instrumentation, Faculty of Applied ScienceKing Mongkut’s Institute of Technology North BangkokBangsueThailand

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