[18F]Fluorodeoxyglucose Single Photon Emission Computed Tomography

Background—New high-energy collimators for single photon emission computed tomography (SPECT) cameras have made imaging of positron-emitting tracers, such as [18F]fluorodeoxyglucose (18FDG), possible. We examined differences between SPECT and PET technologies and between 18FDG and thallium tracers to determine whether 18FDG SPECT could be adopted for assessment of myocardial viability. Methods and Results—Twenty-eight patients with chronic coronary artery disease (mean left ventricular ejection fraction [LVEF]=33±15% at rest) underwent 18FDG SPECT, 18FDG PET, and thallium SPECT studies. Receiver operating characteristic curves showed overall good concordance between SPECT and PET technologies and thallium and 18FDG tracers for assessing viability regardless of the level of 18FDG PET cutoff used (40% to 60%). However, in the subgroup of patients with LVEF≤25%, at 60% 18FDG PET threshold value, thallium tended to underestimate myocardial viability. In a subgroup of regions with severe asynergy, there were c...