LAUSR

Background With appropriate protocols, F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) can visualize myocardial inflammation. Optimal protocols and normative myocardial FDG uptake values are not well-established. Methods We evaluated 111 patients referred for inflammation cardiac FDG PET/CT. Patients followed a low-carbohydrate, high-fat diet for 36 hours before imaging and received unfractionated heparin. Glucose and fatty acid metabolism biomarkers were obtained. Mean blood pool and maximum myocardial uptake (SUV mean , SUV max ) were measured, avoiding areas of abnormal FDG uptake or spillover. Results Adequate suppression of myocardial FDG uptake occurred in 95% of patients (n = 106). Myocardial SUV max was significantly below background blood pool SUV mean : septal myocardial to blood pool ratio 0.75 (95% CI 0.73-0.77; P  < 0.001); lateral myocardial to blood pool ratio 0.70 (95% CI 0.68-0.72; P  < 0.001). Glucose, insulin, and C-peptide correlated to blood pool SUV mean (Spearman r s  = 0.39, P  < 0.01; r s  = 0.40, P  < 0.01; r s  = 0.35, P  < 0.01) and myocardial SUV max (Spearman r s  = 0.31, P  < 0.01; r s  = 0.31, P  < 0.01; r s  = 0.26, P  < 0.01). Fatty acid metabolism biomarkers did not correlate to myocardial SUV max . Conclusions Patients following intensive metabolic preparation have myocardial FDG SUV max below background SUV mean . Biomarkers of glucose metabolism modestly correlate to FDG uptake.