A measurement system for left ventricular volume determination

Abstract

A system for measurement of left ventricular volume is described, in which biplane angiocardiograms are recorded on a video disk. Into the video frames, ECG and pressure curves are coded as well as time references, values of 5 other quantities among which the time elapsed since the preceding R wave sampled at the moment of the X-ray flash, and 1000 characters of alphanumeric information. Videosubtraction is used as a preprocessing technique, after which the ventricular contours are drawn with a light-pen and retained in a digital memory. Via a video computer interface the contour data are fed to a PDP-15 computer which calculates the ventricular volume according to a geometrical model based on measurements of casts of the left ventricle.