QUANTIFICATION OF LEFT-VENTRICULAR FUNCTION WITH AN AUTOMATED BORDER DETECTION SYSTEM AND COMPARISON WITH RADIONUCLIDE VENTRICULOGRAPHY

Quantification of 2-dimensional echocardiograms with a recently develo ped automated border detection (ABD) system provides on-line estimatio n of left ventricular (LV) function. Previous studies showed that shor t-axis cavity area measurements with the ABD system approximate manual ly traced cavity areas obtained with conventional 2-dimensional echoca rdiography. Further clinical validation needs a comparison of LV funct ion between the ABD system and established methods. Fractional area ch ange and ejection fraction measured by the ABD system were compared wi th ejection fraction measured by radionuclide ventriculography. Echoca rdiographic measurements were obtained from LV short-axis views at the level of the papillary muscles. Calculation of ejection fraction by t he ABD system was based on an algorithm using a modified ellipsoid mod el. Forty-six patients underwent echocardiography on the same day as r adionuclide ventriculography. Patients were included in the study if g reater-than-or-equal-to 75% of the endocardium was visualized with con ventional 2-dimensional echocardiography. Twenty-seven of 46 patients (59%) had a technically adequate, conventional echocardiogram. Fractio nal area change with the ABD system was highly correlated with ejectio n fraction from radionuclide ventriculography (r = 0.92; SEE 8.4%). Ej ection fraction determined by the ABD system and radionuclide ventricu lography also showed a strong linear relation in the 23 patients witho ut severe wall motion abnormality (r = 0.90; SEE 9.5%). It is conclude d that LV function measurements by the ABD system and radionuclide ven triculography have a strong linear relation.