In the present work, statistical processing of the electric cardiogram (spectral and bispectral analysis) using the ‘sliding window’ method is proposed and performed. A system for recording and digitizing an electric cardiograms was developed, the output signal of which is fed to a computer. Signal processing is carried out using a system implemented in the LabVIEW environment. It is shown that the time-frequency analysis using the ‘sliding window’ method allows detecting dynamic processes in the work of the human heart, which can go unnoticed in standard analyzes. Research results can be useful for the diagnosis of heart disease.