RESUMEN
PURPOSE: The objectives of this study were - First, to determine the normal range of left ventricular end diastolic volume (EDV), end systolic volume (ESV) and ejection fraction (EF) from gated myocardial perfusion SPECT for Quantitative Gated SPECT (QGS) and 4D-MSPECT (4DM), respectively. Second, to evaluate the relationships between values produced by both software packages. MATERIALS AND METHODS: Tc-99m MIBI gated myocardial perfusion SPECT were performed for 77 patients (mean age: 49.6+/-13.7y, n=37 (M), 40 (F) ) with a low likelihood ( 0.05). In 4DM, the mean EDV, ESV and EF for all patients were 89.1+/-26.4ml, 29.1+/-12.8ml and 68.5+/-6.7% at stress test. Most cases in 4DM, there was no significant difference statistically between stress and rest test (p> 0.05). But statistically significant difference was found in EF (68.5+/-6.7% at stress vs 70.9+/-8.0% at rest, p< 0.05). Correlation coefficients between the methods for EDV, ESV and EF were comparatively high (0.95, 0.93, 0.71 at stress test and 0.95, 0.90, 0.69 at rest test, respectively). However, Bland-Altman plots showed a large range of the limit value of agreement for EDV, ESV and EF between both methods (-30ml 10ml, -12ml 8ml, -14% 11% at stress test and -32ml 5ml, -13ml 13ml, -18% 12% at rest test). CONCLUSION: We found the normal ranges of EDV, ESV and EF for patients with a low likelihood of CAD in both methods. We expect these values will be a good reference to interpret gated myocardial perfusion SPECT. Although good correlation was observed between both methods, they should not be used interchangeably. Therefore, when both programs are used at the same site, it will be important to apply normal limits specific to each method.