Detection and Identification of S1 and S2 Heart Sounds Using Wavelet Decomposition and Reconstruction

Abstract

A heart sound segmentation algorithm has been developed which separates the heart sound signal into four parts: the first heart sound, the systolic period, the second heart sound, and the diastolic period. The algorithm uses discrete wavelet decomposition and reconstruction to produce phonocardiographic intensity envelopes. The performance of the algorithm has been evaluated using 14000 cardiac periods from 100 digital phonocardiographic recordings, including normal and abnormal heart sounds. In tests, the algorithm was over 93 percent correct in detecting the first and second heart sounds.Keywordsphonocardiographyauscultationfirst heart soundsecond heart soundsystolic perioddiastolic periodmurmurswavelet decompositionwavelet reconstructionsegmentationnormalized average Shannon energy