Biplane videoangiography.

Abstract

A biplane videoangio-graphic system for dynamic measurement of the volume and shape of the left ventricle is described. The 2 images of the ventricle are displayed and recorded on the left and right halves of the same video picture. The ecg or a pressure pulse, a code number, and the position of the angio-cardiographic injection syringe plunger are recorded simultaneously on a time-shared basis as analog voltages on an FM [frequency modulation] data track of the same video tape for electronic synchronization of the phase of the cardiac cycle with video events. Synchronized, 1/60 sec, 35-mm pictures of the video screen are used for manual measurement of end-diastolic and systolic volumes. Alternatively, measurement of the horizontal traversal times of the video beam from the edge of the field and between the left and right borders of the 2 projections of the left ventricle for the approximately 50 horizontal lines covering its image will allow on-line computer computation of its volume and shape at the video field rate of 60/sec.