Extensive Biventricular Cardiac Sarcoidosis Detected on FDG PET/CT Using a 72-Hour Ketogenic Diet Preparation Protocol

A 49-year-old man had right bundle-branch block, with decreased left ventricle ejection fraction of 43%. Cardiac MRI demonstrated abnormal multifocal delayed gadolinium enhancement involving both ventricles. Cardiac sarcoidosis was further confirmed at cardiac biopsy. Dedicated FDG PET/CT with 72-hour ketogenic diet preparation to suppress physiological myocardial uptake of FDG was performed for disease evaluation. PET/CT revealed multifocal abnormal uptake in both ventricles concordant with cardiac MRI findings, in addition to hypermetabolic lymphadenopathy. Six months later, posttreatment PET/CT with the same 72-hour ketogenic diet preparation showed good response with resolution of active inflammation.