Clinical Characteristics of Definite or Suspected Isolated Cardiac Sarcoidosis: Application of Cardiac Magnetic Resonance Imaging and 18F-Fluoro-2-deoxyglucose Positron-Emission Tomography/Computerized Tomography

Abstract Background Isolated cardiac sarcoidosis (iCS) is difficult to diagnose in patients without histologic evidence of sarcoidosis. We aimed to clarify the clinical characteristics of iCS, including imaging features on cardiac magnetic resonance imaging (MRI) and 18 F-fluoro-2-deoxyglucose positron-emission tomography/computerized tomography (FDG-PET/CT) scans. We also reviewed the therapeutic effect of corticosteroids and determined the long-term prognosis. Methods and Results We retrospectively reviewed 83 consecutive patients with suspicious CS from 1997 to 2013. Systemic sarcoidosis with CS (sCS, n = 30) and iCS (n = 11) were diagnosed according to clinical criteria. In iCS cases, sarcoidosis was not detected in any other organs. The clinical features did not significantly differ between sCS and iCS cases, except for ejection fraction, which was lower in iCS ( P  = .025). Nine sCS and 4 iCS cases showed late gadolinium enhancement, and the lesions tended to be on the epicardial side (76.9% P  = .011) and septal wall (52.9% P P Conclusions The clinical cardiac characteristics of iCS cases were similar to those of sCS. Cardiac MRI and FDG-PET, noninvasive imaging modalities, could be useful modalities to detect myocardial involvement in the cases with definite or suspected iCS.