Comparison of digital intravenous ventriculography with direct left ventriculography for quantitation of left ventricular volumes and ejection fractions.

Digital images of the left ventricle obtained at 30 frames/second from continuous fluoroscopy after intravenous injection of contrast medium (digital intravenous ventriculography) were used to estimate left ventricular (LV) volumes and ejection fraction with use of several techniques for identifying the ventriculographic silhouette. The digital technique was compared with direct contrast left ventriculography in 26 patients undergoing diagnostic cardiac catheterization. End-diastolic and end-systolic volumes calculated from digital intravenous and direct left ventriculograms were obtained with use of a standard area-length formula. Both end-diastolic volume (EDV) (r = 0.88, y = 1.06x - 17.1 ml) and end-systolic volume (ESV) (r = 0.89, y = 0.96x + 0.43 ml) determined from digital intravenous ventriculography (mask mode images) correlated closely with those obtained by direct left ventriculography. Combining the EDV and ESV to define the relation between the 2 techniques yielded an even closer correlation (r = 0.96). There was also good correlation between the 2 techniques for measurement of ejection fraction (r = 0.81, standard error of the estimate 6.7%). Measurements from direct left ventriculography were frequently invalidated by ventricular arrhythmias during the time of opacification of the left ventricle; this was rarely the case for digital intravenous ventriculography. It is concluded that area-length estimates of LV volumes and ejection fraction can be accurately obtained from digital processing of fluoroscopic LV images after intravenous injection of contrast medium.