Sarcoidosis is a multi-systemic inflammatory disorder of unknown cause characterized by the formation of non-caseating granulomas in involved organs. Its cardiac involvement may be potentially fatal. Although endomyocardial biopsy is required for deﬁnitive diagnosis of cardiac sarcoidosis, it is invasive and lacks sensitivity. The specific diagnostic tool for cardiac sarcoidosis is far from satisfactory. Recent studies have revealed that FDG-PET with under fasting conditions is a useful method for identiﬁcation of cardiac sarcoidosis patients. However, to our knowledge, no investigations have been published with regard to FDG quantification for the diagnosis and management of cardiac sarcoidosis by PET.