Accumulation of fluorodeoxyglucose in ischemic myocardium, 2

Positron emission tomography (PET) using 13N-ammonia and 18F-fluorodeoxyglucose (18FDG) was performed in 33 patients with myocardial infarction to assess myocardial viability of ECG determined infarct segments. 18FDG uptake in infarct segments was compared with myocardial perfusion by 13N-ammonia, coronary stenosis and regional wall motion by contrast ventriculography. Increased 18FDG uptake was more often seen in patients with recent myocardial infarction (RMI) than those with old infarction (p < 0.001). 18FDG uptake was more increased in those with mild hypoperfusion (p < 0.01) and those supplied by recanalized coronary arteries (p < 0.05), suggesting that residual flow to the infarct zone may be crucial to maintain myocardial viability. In RMI, an increase in 18FDG uptake was more often observed in infarct segments with stress induced hypoperfusion (p < 0.02). Furthermore, 18FDG uptake was more increased in those with milder wall motion abnormalities (p < 0.02). However, 18FDG uptake was also observed in 31 % of those with dyskinesis. These data suggest that an increase in 18FDG uptake in infarct segments was observed in area with less severe hypoperfusion and milder regional wall motion abnormalities, indicating 18FDG uptake as a useful predictor of myocardial viability in infarct segments. (author)