The purpose of this study was to compare myocardial perfusion imaging (MPI) with high-speed single-photon emission computed tomography (SPECT) with conventional SPECT imaging for the evaluation of myocardial perfusion in patients with known or suspected coronary artery disease.
Background
A novel technology has been developed for high-speed SPECT MPI by employing a bank of independently controlled detector columns with large-hole tungsten collimators and multiple cadmium zinc telluride crystal arrays.
Methods
A total of 44 patients (39 men) underwent same-day Tc-99m sestamibi stress/rest MPI. High-speed SPECT images were performed within 30 min after conventional SPECT. Stress and rest acquisition times were 16 and 12 min for conventional imaging and 4 and 2 min for high-speed SPECT, respectively. Myocardial counts/min (cpm) were calculated for both conventional SPECT and high-speed SPECT. Images were visually analyzed, and the summed stress score (SSS) and summed rest score (SRS) were calculated. Image quality and diagnostic confidence were qualitatively assessed.
Results
High-speed SPECT SSS and SRS correlated linearly with conventional SPECT respective scores (r = 0.93, p < 0.0001 for SSS, and r = 0.93, p < 0.0001 for SRS). Image quality was rated good and higher in 17 (94%) cases for high-speed SPECT and 16 (89%) cases for conventional SPECT. Of the 44 patients studied, 36 (81.8%) and 35 (79.5%) were diagnosed definitely normal or abnormal by conventional and high-speed SPECT, respectively (p = NS). Myocardial count rate was significantly higher in high-speed versus conventional SPECT (384 × 10−3 ± 134 × 10−3 cpm/min vs. 47 × 10−3 ± 14 × 10−3 cpm/min, respectively, p < 0.0001) for stress and (962 × 10−3 ± 426 × 10−3 cpm/min vs. 136 × 10−3 ± 37 × 10−3 cpm/min, respectively, p < 0.001) for rest.
Conclusions
High-speed SPECT provides fast MPI with high image quality and up to 8 times increased system sensitivity. The amount of perfusion abnormality visualized by high-speed SPECT is highly correlated to conventional SPECT, with an equivalent level of diagnostic confidence.
Abbreviations and acronyms
CAD
coronary artery disease
CZT
cadmium zinc telluride
LAD
left anterior descending coronary artery
MLEM
maximum likelihood expectation maximization method
RCA
right coronary artery
ROI
region of interest
SPECT
single-photon emission computed tomography
SRS
summed rest score
SSS
summed stress score
2D
2-dimensional
Cited by (0)
This study was funded by Spectrum Dynamics. Drs. Berman and Ben Haim own shares in Spectrum-Dynamics. Dr. Sharir is a consultant for Spectrum-Dynamics.
