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Myocardial perfusion SPECT is an excellent tool for the assessment of coronary artery disease (CAD); however, it is affected by several artifacts, such as patient motion during acquisition, which increases false-positive rates. Therefore, the purpose of this work is to analyze changes in perfusion scores after motion-correction software application.The population included 160 (99m)Tc-sestamibi CAD studies, divided into two groups: with and without perfusion defects, equally divided into subgroups according to movement during standard acquisition. A Siemens ECAM 180 was used for processing without correction and with automatic and manual e.soft 2.5 modalities. Visual interpretation as well as QPS software was compared using Pearson correlation and kappa agreement statistics.Moderate agreement was observed between SPECT interpretations after motion correction versus the original report, according to the presence of perfusion defects. Manual correction using the software obtained the lowest agreements. Perfusion summed stress scores (SSS) correlation from different processing modalities versus non-corrected studies differed significantly independent of the degree of motion. Mean SSS in 40 patients with no motion was 3.9 + or - 3.9 when no correction was applied; with automatic correction was 8.8 + or - 10 (p = 0.03) and with manual correction was 3.1 + or - 3.5 (p = ns versus non-corrected). Automatic correction was better when applied to patients with mild to moderate motion. In those with mild or no motion, software overestimated or created new perfusion defects.Motion-correction software must be used with caution when trying to optimize myocardial perfusion SPECT based on individual analysis. Acquisition should be always repeated in cases with severe motion and in no or mild motion it seems preferable to avoid correction.

Accurate assessment of ventricular function is required to optimize therapeutic management of cardiac diseases. The aim of this study was to correlate planar equilibrium multigated acquisition (MUGA) with tomographic ventriculography (SPECT) in patients with diverse volumes and wall motion abnormalities.Eighty-three studies in 80 patients (56+/-14 years; 56% women) were classified according to ventricular dilation, wall motion abnormalities and systolic dysfunction. Left and right ventricular ejection fraction (LVEF and RVEF) and end-diastolic and end-systolic left ventricular volumes (EDV and ESV) were obtained using a commercial QBS program for SPECT. On planar acquisition, LVEF and RVEF were obtained using standard techniques and volumes were determined using the count-based method, without blood sampling.A. Total group: With the planar method, LVEF was 44+/-17%, RVEF 42+/-13%, left EDV 147+/-97 ml (range 31-487 ml) and left ESV 93+/-85 ml (range 15-423 ml); with SPECT the corresponding values were 40+/-20%, 49+/-16%,131+/-95 ml and 91+/-89 ml, respectively (p=NS for all but RVEF). Linear correlation was 0.845 for LVEF, 0.688 for RVEF, 0.927 for left EDV and 0.94 for left ESV, with good intra-class correlation. B. Subgroups: Global and intra-class correlations between planar imaging and SPECT were high for volumes, RVEF and LVEF in all subgroups, except in patients with normal wall motion and function, who showed smaller volumes with SPECT. The group with diffuse wall motion abnormalities had a lower EDV on SPECT. In the abnormal left ventricle, RVEF was higher with SPECT.Good correlation and agreement exist between SPECT and planar MUGA with respect to LVEF and left ventricular volumes. SPECT is useful in patients with functional abnormalities, but less reliable in those with normal small cavities. A combined technique is still necessary, and RVEF should be interpreted cautiously.