Ultrasonic Doppler Method for the Inspection of Cardiac Functions

When the continuous ultrasonic wave is sent forth towards the heart from the surface of the chest wall, the cardiac motion causes the Doppler effect upon the partial wave reflected from it. Therefore, an apparatus suitably constructed for sending and receiving ultrasounds is quite useful for the investigation of the movements of theatrium, ventricle, or valves, etc., through the analysis of the particular Doppler signals developed from the motion of the respective part. The author developed a method for the inspection of cardiac functions by recording these Doppler signals simultaneously with the electro- and phonocardiographs the oscillograph paper. This method made it possible not only to obtain direct informations for the valvular movement which could not have been ascertained up to present, but also to examine the transitional aspects of the myocardial excitation which is utterly uudetectable by the electrocardiograph alone.