ECG-gated 18F-FDG positron emission tomography

Area of Science:

• Cardiology
• Nuclear Medicine
• Medical Imaging

Background:

• 18F-fluorodeoxyglucose (18F-FDG)-positron emission tomography (PET) assesses myocardial glucose metabolism for viability.
• Current methods comparing PET with other imaging techniques face transfer uncertainty and scatter.
• Assessing both metabolic and functional status in a single study is crucial for diagnosing left ventricular dysfunction.

Purpose of the Study:

• To evaluate a novel Fourier-based ECG-gated PET technique for assessing myocardial viability and function.
• To determine the feasibility of this technique in patients with diseased left ventricles.
• To compare the reliability of this new PET method with established diagnostic criteria.

Main Methods:

• Forty-five patients with coronary artery disease and left ventricular hypokinesis or akinesis were studied.
• A Fourier-based ECG-gated 18F-FDG-PET was performed.
• A 36-segment model was used to analyze resting function and 18F-FDG uptake.

Main Results:

• The PET technique showed high reliability (>96%) in identifying dysfunctional left ventricular segments.
• 18F-FDG uptake was significantly different across normokinetic, hypokinetic, and akinetic segments (p < 0.001).
• Viability was confirmed in akinetic segments with >=70% 18F-FDG uptake and in hypokinetic segments with >=40% uptake.

Conclusions:

• ECG-gated metabolic PET with Fourier smoothing reliably provides regional functional and metabolic data.
• This integrated approach allows for complete segmental status assessment within one study, avoiding transfer artifacts.
• The study indicates significant myocardial viability in regions with 40-50% 18F-FDG uptake.