Evaluation of left ventricular performance in infants and children using radionuclide angiography.

Eight quantitative first-pass (FP) radionuclide angiograms were performed in six children with left ventricular (LV) dysfunction without associated LV outflow obstruction and one infant with obstructive cardiomyopathy (CM) to define regional and global LV function. All patients (3 months to 15 years) had clinical findings of congestive heart failure. Echocardiographic evaluation was performed within 24 hours of the FP study. LV ejection fraction (LVEF), regional ejection fraction index (REFI), LV wall motion perimeters, transit time, and curve analysis were evaluated. Ejection fraction by FP-RNA was compared to echo in all patients. FP-RNA derived end-diastolic and end-systolic LV perimeters were compared to corresponding contrast angiographic definition of LV wall boundaries. FP-LVEF ranged from 23-44% in 6 patients with non-obstructive CM and was 79% in 1 patient with obstructive CM. REFI revealed diffuse hypokinesis in 6 patients with nonobstructive CM, with additional apical akinesis in 1 patient. The infant with obstructive CM had hyperdynamic wall motion. These data compared favorably with echo EF and angiographic assessment of LVEF and wall motion.