TY - JOUR T1 - Effect of Perfusion Pattern and Imaging Sequence on Gated Perfusion SPECT Evaluation of Myocardial Stunning JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 176 LP - 183 VL - 46 IS - 1 AU - Alain Manrique AU - Anne Hitzel AU - David Brasse AU - Pierre Véra Y1 - 2005/01/01 UR - http://jnm.snmjournals.org/content/46/1/176.abstract N2 - The aim of this study was to determine the effect of perfusion defect and imaging sequence on the evaluation of myocardial stunning with gated perfusion SPECT. Methods: A dynamic mathematic cardiac torso phantom was used to create 100 gated SPECT simulations (50 stress-rest and 50 rest-stress sequences) with a wide range of perfusion defects. No segmental wall motion abnormalities were created. After generating projection images, 2 additional acquisitions were simulated by thresholding the projected data to 25% and 75% of the maximum. Finally, gated SPECT projections were grouped by 2s to generate 2 series of phantoms corresponding to stress-rest and rest-stress imaging sequences. For each sequence, the first dataset was the 25% thresholded gated SPECT. Both 75% thresholded and 100% signal intensity were used as a second dataset. Each simulated gated SPECT image differed from others in the extent of myocardial scar or ischemia, but all had the same end-diastolic volume (EDV) (125 mL), end-systolic volume (ESV) (48 mL), and ejection fraction (EF) (62%). Left ventricular perfusion and function were each assessed using validated software. Results: Mean stress EDV was decreased when compared with rest-simulated data (111 ± 4.7 and 112.4 ± 4.8 mL, respectively; P ≤ 0.05), and mean stress ESV was increased when compared with rest-simulated data (44 ± 4.2 and 42.7 ± 4 mL, respectively; P < 0.02). The resulting mean stress EF was decreased in the same comparison (60.3% ± 3.1% and 62% ± 2.7%, respectively; P = 0.0001). After multivariate analysis, the difference between stress and rest EF was significantly influenced by myocardial infarction (P = 0.0027), severe extent of myocardial ischemia (P = 0.0017), and imaging sequence (P < 0.0001). A ≥5% decrease in EF on stress SPECT (i.e., myocardial stunning) was significantly associated with the stress-rest sequence (χ2 = 26; P < 0.0001). Conclusion: Perfusion defects and imaging sequence had significant effects on the evaluation of myocardial stunning using gated perfusion SPECT. ER -