title: The effect of metabolic milieu on cardiac PET imaging using fluorine-18-deoxyglucose and nitrogen-13-ammonia in normal volunteers.
abstract: Cardiac PET imaging using 13N-ammonia and 18FDG was performed on 17 normal volunteers in the glucose-loaded and fasted states. PET images (glucose-loaded and fasted) were subjected to qualitative visual analysis using the descriptors: image quality, FDG blood-pool activity, ammonia lung field activity, and clinical interpretability. Glucose-loaded studies had better image quality, diminished FDG blood-pool activity, and were more often clinically interpretable compared to fasted studies. Dietary state did not affect 13N-ammonia study parameters. Using a semi-quantitative region of interest method, 18FDG myocardial activity was homogeneous and significantly affected by dietary state (2.48 +/- 1.0 fold increase in myocardial-to-blood pool ratio in glucose-loaded versus fasted states). Serum glucose, insulin, and free-fatty acid concentrations responded physiologically to glucose loading and fasting but showed no correlation with myocardial 18FDG uptake. PET imaging using 13N-ammonia and 18FDG appears optimal in the glucose-loaded state.
authors.affiliation: Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor.
authors.forename: J J
authors.initials: JJ
authors.lastname: Berry
authors.forename: J A
authors.initials: JA
authors.lastname: Baker
authors.forename: K S
authors.initials: KS
authors.lastname: Pieper
authors.forename: M W
authors.initials: MW
authors.lastname: Hanson
authors.forename: J M
authors.initials: JM
authors.lastname: Hoffman
authors.forename: R E
authors.initials: RE
authors.lastname: Coleman
mesh_terms: D000328:Adult; D000641:Ammonia; D001786:Blood Glucose / Q000032:analysis; D003847:Deoxyglucose / Q000031:analogs & derivatives; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007328:Insulin / Q000097:blood; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism*; D009590:Nitrogen Radioisotopes; D014055:Tomography, Emission-Computed
chemical_list: D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D005462:Fluorine Radioisotopes; D007328:Insulin; D009590:Nitrogen Radioisotopes; D019788:Fluorodeoxyglucose F18; D000641:Ammonia; D003847:Deoxyglucose