Patients prepared by the generally used fasting protocol show variable myocardial (18)F-FDG uptake, which may result in difficult interpretation of mediastinal (18)F-FDG uptake. This retrospective study described the effect of a 1-d fat-allowed, carbohydrate-restricted diet on myocardial (18)F-FDG uptake.
Methods: The study included 100 patients on a carbohydrate-restricted diet from the Medical Center Leeuwarden and 100 patients on an unrestricted diet from the University Medical Center of Utrecht. A visual uptake scale was used, with category 0 indicating myocardial uptake less than liver uptake, category 1 indicating myocardial uptake comparable to liver uptake, and category 2 indicating myocardial uptake considerably higher than liver uptake.
Results: After a carbohydrate-restricted diet, 68% of patients had a homogeneously low myocardial uptake of (18)F-FDG (category 0), 14% had moderate myocardial uptake (category 1), and 18% had homogeneously intense myocardial uptake (category 2). Without a carbohydrate-restricted diet, 69% of patients showed a homogeneously intense myocardial uptake (category 2), 16% a moderate myocardial uptake (category 1), and 15% a homogeneously low myocardial uptake (category 0).
Conclusion: A fat-allowed, carbohydrate-restricted diet starting the day before (18)F-FDG administration suppresses myocardial (18)F-FDG uptake satisfactorily.