Objectives: Electrocardiographically gated blood pool SPECT (GBPS) is an interesting method for measuring left ventricular (LV) ejection fraction (LVEF) and volume. Recently, the availability of completely automatic GBPS processing software has been reported. We aimed to evaluate its reliability in measuring global LV systolic function. In addition, using the same population, we compared its reliability to that of three previously reported methods for processing GBPS.
Methods: We studied the performances of the new GBPS system for the evaluation of LVEFs and volumes in 29 patients. The LVEF provided by the planar equilibrium radionuclide angiography (planarLAO) and LV volumes provided by radiological LV contrast angiography (X-rays) were used as 'gold standards'.
Results: The new GBPS system failed in one patient. It shows good reproducibility for the measurement of both LVEF and volume. LVEF provided by this system is moderately correlated to planarLAO (r = 0.62; P < 0.001). The new GBPS constantly overestimates LVEF (P < 0.05). Results for LV volumes are moderately correlated to those obtained by X-ray investigation (r = 0.7; P < 0.001) but are significantly lower (P < 0.0001). There is a linear correlation between the average and the paired absolute difference for LV volumes (r = 0.52, P = 0.0001).
Conclusions: The new, completely automatic, GBPS processing software is an interesting, moderately reliable method for measuring LVEF and volume. The performance of the method is lower than that previously reported for the same population for the other three GBPS processing methods.