Detailed visualization of the right and left ventricular, left atrial, and epicardial involvement of cardiac sarcoidosis with novel semiconductor PET/CT

Abstract

A female in her 50s presented with dyspnea on exertion. She had a history of cutaneous mass at her right eyelid, which was resected and histologically confirmed as sarcoidosis. Echocardiography revealed left ventricular (LV) asynergy with reduced LV function (ejection fraction, 34%). Cardiac sarcoidosis (CS) was suspected, and a novel positron emission tomography (PET) system equipped with digital photon counters and time-offlight technology (Digital TF; Philips Healthcare, Cleveland, OH, USA) and magnetic resonance imaging (MRI) were performed. F-fluorodesoxyglucose (FDG) PET under > 18-h fasting with a low-carbohydrate diet preparation [1] revealed focal uptakes in the lymph nodes at the bilateral hilum and mediastinum, which was characteristic of sarcoidosis (A). In addition, multiple focal strong cardiac uptakes (SUVmax 12.7) indicating active CS were observed (B, E). On MRI, late gadolinium enhancement was observed in the left ventricular wall, confirming myocardial infiltration (C, F). PET and MRI fusion images well explained the locations of FDG uptake not only in the LV wall but also in papillary muscle (blue arrow), the left atrium (red arrow), epicardium (yellow arrow), and right ventricle (white arrow), which were not easily identified on MRI (D, G). After 1 month of treatment with corticosteroids, the uptake in the lymph nodes had disappeared, and cardiac uptake remained but was markedly reduced (SUVmax 4.6) (H). Digital PET/CT may thus have the potential for detecting and characterizing small lesions of CS [2].