left ventricular ejection fraction determined with the simulation of a very low-dose czt-spect protocol and an additional count-calibration on planar radionuclide angiographic data

To determine whether the left ventricular ejection fractions (efs), measured on a high-sensitivity czt single photon emission computed tomography (spect)-camera with a 70% reduction in recording times and a prevention of ef overestimation through an additional count-calibration, are concordant with reference ef from planar radionuclide angiography (2d-rna). an additional 10-minute czt-spect recording was performed in patients referred to 2d-rna for cardiomyopathy (n = 23) or chemotherapy monitoring (n = 50) with an in vivo red blood cell labeling with 850 mbq $$ {}^{{99{text{m}}}}{text{tco}}_{4}^{ - } $$ . the ef, obtained from czt-spect with 100% (spect100) or 30% (spect30) projection times and with a spect-count calibration on the 2d-rna counts of corresponding cavity volumes, were compared to ef from 2d-rna. strong and equivalent relationships were documented between the ef from 2d-rna and the calibrated ef from spect100 (y = 0.89x + 6.62; r2 = 0.87) and spect30 (y = 0.87x + 8.40; r2 = 0.85), and the mean ef from spect100 (54% ± 15%) and spect30 (53% ± 16%) were close to that from 2d-rna (55% ± 15%). however, upward shifts in these mean values were documented in the absence of count calibration for both spect100 (60% ± 18%) and spect30 (60% ± 18%). left ventricular ef be determined on a high-sensitivity czt-camera, a 70% reduction in injected activities, and an additional count-calibration for further enhancing the concordance with 2d-rna values.