[Spectrum analysis of heart sounds in chronic coronary insufficiency].

Major heart tone amplitude-frequency characteristics were studied in relation to central hemodynamics and physical stress tolerance in 147 chronic coronary patients. A method of spectrogram assessment is proposed that includes the measurement of spectrum width, resonance frequency and the Q-factor. Amplitude-frequency studies demonstrated limited left-ventricular vibration capacity with reduced myocardial contractility and increased myocardial weight. The results of bicycle ergometry were correlated with heart tone spectrum data. A relationship was demonstrated between changes in major parameters of tone 1 and the double product, threshold capacity for exercise and the output.