UTILIZATION OF INSTANTANEOUS EJECTION VOLUME IMAGES TO PRODUCE VENTRICULAR VOLUME CURVES FROM AN EQUILIBRIUM RADIONUCLIDE VENTRICULOGRAM

Equilibrium radionuclide ventriculograms were performed in 6 normal do gs during resting and isoproterenol challenged states. A new method of analysis of the equilibrium radionuclide ventriculograms using a simp le digital subtraction technique was compared to traditional methods o f analysis and echocardiography. There was ho significant difference b etween ejection fraction values from the three methods tested. The equ ilibrium radionuclide ventriculograms ejection fraction was significan tly increased following isoproterenol administration using both the ne w and traditional methods of analysis but the pre versus post-isoprote renol increase ejection fraction derived from echocardiographic measur ements of ejection fractions was not significantly different. The new digital subtraction method consistently produced reproducible, high qu ality ventricular volume curves for the left and right ventricle. Left and right ventricular maximum and average emptying and filling rates were determined from the slopes of the volume curve and the results we re similar to those previously published for man and dog. The emptying and filling rates of both ventricles were significantly increased fol lowing isoproterenol administration. The time to peak emptying signifi cantly decreased following isoproterenol. Time to peak filling decreas ed following isoproterenol but the difference was not significant.