Determination of Pressure Gradient in Mitral Stenosis with a Non‐invasive Ultrasound Doppler Technique

A 2 MHz continuous waveform non-invasive ultrasound doppler system has been used in the present investigation. With the aid of the audio signals of the frequency shifts, the ultrasound probe was positioned on the external chest so that the axis of the incident ultrasonic beam coincided with the direction of the maximum velocity vectors of the mitral jet. The frequency shifts due to the mitral jet were frequency analyzed and the time course of...