ECG-gated 18F-FDG positron emission tomography.
OBJECTIVE
18F-fluorodeoxyglucose (18F-FDG)-positron emission tomography (PET) provides information about myocardial glucose metabolism to diagnose myocardial viability. Additional information about the functional status is necessary. Comparison of tomographic metabolic PET with data from other imaging techniques is always hampered by some transfer uncertainty and scatter. We wanted to evaluate a new Fourier-based ECG-gated PET technique using a high resolution scanner providing both metabolic and functional data with respect to feasibility in patients with diseased left ventricles.


METHODS
Forty-five patients with coronary artery disease and at least one left ventricular segment with severe hypokinesis or akinesis at biplane cineventriculography were included. A new Fourier-based ECG-gated metabolic 18F-FDG-PET was performed in these patients. Function at rest and 18F-FDG uptake were examined in the PET study using a 36-segment model.


RESULTS
Segmental comparison with ventriculography revealed a high reliability in identifying dysfunctional segments (> 96%). 18F-FDG uptake of normokinetic/hypokinetic/akinetic segments was 75.4 +/- 7.5, 65.3 +/- 10.5, and 35.9 +/- 15.2% (p < 0.001). In segments > or = 70% 18F-FDG uptake no akinesia was observed. No residual function was found below 40% 18F-FDG uptake. An additional dobutamine test was performed and revealed inotropic reserve (viability) in 42 akinetic segments and 45 hypokinetic segments.


CONCLUSIONS
ECG-gated metabolic PET with pixel-based Fourier smoothing provides reliable data on regional function. Assessment of metabolism and function makes complete judgement of segmental status feasible within a single study without any transfer artefacts or test-to-test variability. The results indicate the presence of considerable amounts of viable myocardium in regions with an uptake of 40-50% 18F-FDG.
Klinik für Kardiologie und Allgemeine Innere Medizin, Städtisches Klinikum Solingen, Germany.
Hans Martin
HM
Hoffmeister
Uwe
U
Helber
Andreas
A
Franow
Ulrich
U
Feine
Roland
R
Bares
Ludger
L
Seipel
Wolfgang
W
Müller-Schauenburg
D000328:Adult; D000368:Aged; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D004280:Dobutamine; D005260:Female; D019788:Fluorodeoxyglucose F18; D015637:Gated Blood-Pool Imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D019275:Radiopharmaceuticals; D014055:Tomography, Emission-Computed; D016277:Ventricular Function, Left / Q000502:physiology*
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D004280:Dobutamine