[Time-varying spectral analysis of cardiac murmurs].

In this paper, the cardiac murmurs (systolic murmurs, diastolic murmurs and machining murmurs) are classified by hemodynamics and studied by time-frequency analysis. We get the time-varying spectrum of the signals. The results, which are from the different kinds of murmurs in 28 patients with heart disease, show that the time-varying spectrum based on cone-shaped kernel distribution are capable to correctly represent the power density and dynamic course of the series in time-frequency domain. The method has high time-frequency resolution, and the time-varying spectrum of each murmur has its characteristics.