We compare thallium-201 rest redistribution and fluorine-18 fluorodeoxyglucose ([18F]FDG) for the assessment of myocardial viability within technetium-99m methoxyisobutylisonitrile (MIBI) perfusion defects in 27 patients with chronic stable coronary artery disease. The following studies were performed: (1) stress99mTc-MIBI, (2) rest99mTc-MIBI, (3)201T1 rest-redistribution single-photon emission tomography, (4) [18F]FDG positron emission tomography. The left ventricle was devided into 11 segments on matched tomographic images. The segment with the highest activity at stress was taken as the reference (activity=100%). Perfusion defects at99mTc-MIBI rest were classified as severe (activity18F]FDG and rest-redistributed201Tl were recognized as significant if they exceeded 50% of that in the reference segment. Among the 33 segments with severe99mTc-MIBI rest perfusion defects, 21 had significant [18F]FDG and 10 significant rest-redistributed201Tl uptake. As regards the 37 segments with moderate defects, [18F]FDG was present in 29 and201Tl in 31, while of the 134 segments with mild defects, 128 showed [18F]FDG uptake, and 131,201Tl uptake. In conclusion, there is an inverse relationship between the severity of99mTc-MIBI perfusion defects and the uptake of rest-redistributed201Tl and [18F]FDG. Both tracers are adequate markers of viability in mild and moderate defects; in severe defects201Tl might underestimate the presence of viability as assessed by [18F]FDG.
- Myocardial perfusion
- Myocardial viability
- Positron emission tomography
- Single-photon emission tomography
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging