Role of Metabolic Imaging in Detecting Cardiac Involvement in Sarcoidosis.

pensity for physiological myocardial 18F-FDG uptake.8 This being the case, JSNC recommendations based on recent studies have suggested preparation involving long fasting and diet modification prior to 18F-FDG PET studies.5,9 Given the challenges associated with 18F-FDG preparation, alternative diagnostic approaches for CS are being sought. In this issue of the Journal, Momose et al assess the diagnostic value of 123I-β-methyl-p-[123I]-iodophenyl-pentadecanoic acid (123I-BMIPP) single-photon emission computed tomography (SPECT) imaging in patients with suspected CS.10 A 123I-BMIPP abnormality reflects the myocardial metabolic shift often seen after the resolution of severe myocardial ischemia, so-called “ischemic memory imaging”, and is considered to be a sign of past myocardial injury.11 The usefulness of 123I-BMIPP for detecting CS has previously been suggested,12 but he strength of the current study by Momose et al lies in the fact that they compared 123I-BMIPP findings to those determined using current state-of-the-art diagnostic testing. ardiac sarcoidosis is considered to be a significant cause of advanced atrioventricular (AV) block or ventricular tachyarrhythmia (VT) in the young to middleaged population.1 The Heart and Rhythm Society (HRS) therefore recently raised the clinical importance of detecting cardiac involvement of sarcoidosis (CS).2 Although the total number of sarcoidosis cases in the Japanese population is limited,3 the frequency of cardiac involvement is significantly higher in the Japanese population than in other populations.4 Therefore, Japanese investigators have worked intensively to develop relevant diagnostic approaches, especially those involving 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET).5–7