Analysis of small vibrations on the heart wall measured by ultrasonic Doppler for noninvasive diagnosis of cardiac muscle dysfunction

To diagnose ventricular dysfunction based on acoustic characteristics of the heart muscle, it is necessary to measure small vibration signals from various parts of the ventricular walls noninvasively. We previously proposed a noninvasive method for measuring these vibrations using Doppler ultrasonography. Here we present the spectra of the small vibration signals from the heart wall that we obtained using this method. Clear differences between the resultant power spectra of the small vibration signals measured on the interventricular septum in normal individuals and those of patients who had been receiving carcinostatic medication for a long time were observed. This study thus confirms the potential usefulness of the new method proposed for measuring small vibration signals on the heart wall.