Assessment of left ventricular ejection fraction (LVEF) on QGS, ECT and 4DM-SPECT with comparison to cardiac catheterization (CC) and cardiac echocardiogram (CE) in nuclear myocardial perfusion imaging (MPI)

Objectives Comparison and evaluation of LVEF between software programs (QGS, ECT and 4DM-SPECT) in MPI with CC and CE.

Methods 699 subjects (361 M, 338 F) with or without known CAD were retrospectively studied. The patients were selected by searching the radiology database at UNMC and CUMC. Subjects were classified into 2 groups, which LVEF was calculated either by QGS and ECT (EF method is R1) at CUMC or by 4DM-SPECT and ECT at UNMC and compared with LVEF was reported on CC and CE. Finally, correlation between gender, age, BMI, DM, FH and the modalities for estimation of LVEF were studied. Differences in means of these data were evaluated with paired t-tests. Pearson correlation coefficients were computed.

Results Patient age range was 30-99 years old (mean 65.7 ± 12.6), BMI from 14-64 (mean 32.3 ± 8.2), EDV from 11-340 (Mean 112 ± 48.6) ESV from 2-298 (mean 49 ± 39.9). Correlation of ECT RLVEF with QGS RLVEF and 4DM- SPECT RLVEF were 0.8461 and 0.7783 respectively. Correlation of ECT SLVEF with QGS SLVEF and 4DM- SPECT SLVEF were 0.920 and 0.883 respectively. Correlation between CC and CE shows 0.561 and 0.468 at Creighton and UNMC respectively. At neither institution there is a significant difference between the means for CC and CE (P values 0.32 and 0.29 respectively). Finally the data shows CC has LVEF mean (56.4 ± 10.0) which is the closest to ECT LVEF mean (56.0± 14.9 and 55.1 ± 14.2 for rest and stress respectively) and CE has LVEF mean (52.7± 12.1), which is the closest to QGS LVEF mean (52.6± 14.3 and 53.7 ± 14.4 for rest and stress respectively). 4D-MSPECT LVEF mean (65.5± 15.0 and 64.1 ± 14.8 for rest and stress respectively) is the most far from either software to CC or CE.

Conclusions LVEF mean estimates by CC is the closest to LVEF mean calculated by ECT and LVEF mean estimated by CE is the closest to LVEF mean calculated by QGS.