Quantitative myocardial-perfusion SPECT: Comparison of three state-of-the-art software packages

Background: We aimed to compare the automation and diagnostic performance in the detection of coronary artery disease (CAD) of the 4DMSPECT (4DM), Emory Cardiac Toolbox (EMO), and QPS systems for automated quantification of myocardial perfusion. Methods and Results: We studied 328 patients referred for rest/stress Tc-99m sestamibi imaging, 140 low-likelihood patients and 188 with angiography. Contours were corrected when necessary. All other processing was fully automated. A 17-segment analysis was performed, and a summed stress score (SSS) ≥4 was considered abnormal. The average SSSs (±SD) for 4DM, EMO, and QPS were 10.5 ± 9.4, 11.1 ± 8.3, and 10.1 ± 8.9, respectively (P = .02 for QPS versus EMO). The receiver operator characteristics areas-under-the-curve for the detection of CAD (±SEM) were 0.84 ± 0.03, 0.76 ± 0.04, and 0.88 ± 0.03 for 4DM, EMO, and QPS, respectively (P = .001 for QPS versus EMO, and P = .03 for 4DM versus EMO). Normalcy rate was higher for QPS and 4DM versus EMO, at 91% and 94% versus 77%, respectively (P = .02). Sensitivity was higher for QPS (87%) versus 4DM (80%) (P = .045). Specificity was higher for QPS (71%) versus EMO (49%) (P = .01). The accuracy rate was higher for QPS versus 4DM and EMO, at 83% versus 77% and 76%, respectively (P = .05). Conclusions: There are differences in myocardial-perfusion quantification, diagnostic performance, and degree of automation of software packages.