Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology Isolated Cardiac Sarcoidosis: A Focused Review of An Under-recognized Entity 1David R. Okada, 2Paco E. Bravo, 3Tomas Vita, 3Vikram Agarwal, 4Michael T. Osborne, 2Viviany Taqueti, 2,3Hicham Skali, 5Panithaya Chareonthaitawee, 2,3Sharmila Dorbala, 2Garrick Stewart, 2,3Marcelo Di Carli, 2,3Ron Blankstein   1Division of Cardiology, Department of Medicine, Johns Hopkins Hospital, 2Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women’s Hospital, 3Department of Radiology, Brigham and Women’s Hospital, 4Cardiology Division, Department of Medicine, 5Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic Copyright American Society of Nuclear Cardiology

Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology BACKGROUND 1- There is accumulating evidence for a distinct clinical phenotype characterized by isolated cardiac involvement. 2- Established criteria for the diagnosis of cardiac sarcoidosis (CS) are insensitive for isolated cardiac sarcoidosis (ICS) since they require either evidence of extra-cardiac disease or a positive endomyocardial biopsy (EMB), which itself is highly limited in its sensitivity. 3- Therefore, alternative diagnostic approaches to diagnose ICS would facilitate further investigation into the epidemiology, pathobiology, clinical course, and optimal treatment of ICS. Copyright American Society of Nuclear Cardiology

Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology METHODS We performed a comprehensive search of the literature using the search items “cardiac sarcoidosis” and “isolated cardiac sarcoidosis” and reviewed all relevant results. Copyright American Society of Nuclear Cardiology

Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology RESULTS Copyright American Society of Nuclear Cardiology

Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology RESULTS Figure 1. Example of the complementary value of CMR and cardiac PET imaging in detecting cardiac sarcoidosis. A 61 year old male presented with systolic heart failure of unknown etiology. CMR showed late gadolinium enhancement in the basal and mid anterior, anteroseptal, and inferoseptal segments that extended into the right ventricle. Myocardial perfusion imaging showed mild perfusion defects in the mid inferoseptal and the mid anterior segments. There was FDG uptake involving the basal to mid anterior and anteroseptal, basal inferior and apical septal segments. In this case the combined information provided by PET and CMR can enhance the diagnostic certainty for diagnosing cardiac sarcoidosis, as subsequently was also confirmed via biopsy. Copyright American Society of Nuclear Cardiology

Journal of Nuclear Cardiology | Official Journal of the American Society of Nuclear Cardiology CONCLUSIONS 1- The rate of ICS among patients with CS appears to be approximately 25%. 2- Patients with ICS appear to have worse left ventricular systolic function at presentation and a higher rate of incident ventricular tachycardia as compared with patients with systemic sarcoidosis with CS. 3- Because of limitations in current diagnostic criteria, there is an important role for advanced cardiac imaging techniques in the evaluation of patients with suspected ICS. 4- A combined approach using FDG PET and CMR may provide complementary data on both inflammation and scar or fibrosis, respectively. Copyright American Society of Nuclear Cardiology