[Assessment of left ventricular function and volume by myocardial perfusion scintigraphy--comparison of two algorithms].
OBJECTIVE
Left ventricular volume and function can be computed from gated SPECT myocardial perfusion imaging using Emory Cardiac Toolbox (ECT) or Gated SPECT Quantification (GS-Quant). The aim of this study was to compare both programs with respect to their practical application, stability and precision on heart-models as well as in clinical use.


METHODS
The volumes of five cardiac models were calculated by ECT and GS-Quant. 48 patients (13 female, 35 male) underwent a one day stress-rest protocol and gated SPECT. From these 96 gated SPECT images, left ventricular ejection fraction (LVEF), end-diastolic volume (EDV) and end-systolic volume (ESV) were estimated by ECT and GS-Quant. For 42 patients LVEF was also determined by echocardiography.


RESULTS
For the cardiac models the computed volumes showed high correlation with the model-volumes as well as high correlation between ECT and GS-Quant (r > or = 0.99). Both programs underestimated the volume by approximately 20-30% independent of the ventricle-size. Calculating LVEF, EDV and ESV, GS-Quant and ECT correlated well to each other and to the LVEF estimated by echocardiography (r > or = 0.86). LVEF values determined with ECT were about 10% higher than values determined with GS-Quant or echocardiography. The incorrect surfaces calculated by the automatic algorithm of GS-Quant for three examinations could not be corrected manually. 34 of the ECT studies were optimized by the operator.


CONCLUSIONS
GS-Quant and ECT are two reliable programs in estimating LVEF. Both seem to underestimate the cardiac volume. In practical application GS-Quant was faster and easier to use. ECT allows the user to define the contour of the ventricle and thus is less susceptible to artifacts.
Zajic
T
T
Abteilung Nuklearmedizin, Klinikum der Albert-Ludwigs-Universität, Freiburg, Deutschland. tzajic@ukl.uni-freiburg.de
Fischer
R
R
Saurbier
B
B
Brink
I
I
Moser
E
E
Krause
T
T
D000465:Algorithms; D015637:Gated Blood-Pool Imaging; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D015203:Reproducibility of Results; D013599:Systole; D015899:Tomography, Emission-Computed, Single-Photon; D016277:Ventricular Function, Left