Instantaneous assessments of left ventricular dimensions by ultrasonic analogue conversion system. I. An experimental...

A new time-to-voltage analogue converter of ultrasound echo was made. The converter samples the echoes from the septal endocardium and the endocardium of the posterior wall of the left ventricle. The converter also enables automatic calculates left ventricular minor axis, volume, and work. In fixed human hearts, the left ventricular minor axis and volume calculated by the converter were close to the actual ones. In anesthetized dogs, left ventricular minor axis, volume, ejection fraction and stroke work calculated by the converter were close to those calculated by cineventriculography. The results indicate applicability of the ultrasonic analogue converter for instantaneous assessments of left ventricular dimensions and function.