Phonometric study of the second heart sound in normal man.
The fast Fourier transform (FFT) was employed to analyze the frequency spectra of the second heart sound in 19 healthy subjects. The data obtained show that the second heart sound is mainly composed of low-frequency vibrations, and that the frequency vs. amplitude spectra for the various filters do not exceed 150 Hz. The different spectra obtained can represent a useful reference to compare with pathological acoustical findings.
D000328:Adult; D005583:Fourier Analysis; D006326:Heart Auscultation / Q000379:methods*; D006347:Heart Sounds / Q000379:methods*; D006801:Humans; D010701:Phonocardiography / Q000379:methods; D013057:Spectrum Analysis