Aims To determine the diagnostic performance and clinical usefulness of 18 F-fluorodeoxyglucose ( 18 F-FDG) PET computerised tomography (CT) in detecting cardiac inflammation in patients with suspected cardiac sarcoidosis; and to explore the role of interval and correlative imaging. Material and methods A 10-year (2015–2024) retrospective observational study was conducted at our teaching hospital. 397 18 F-FDG PET-CT scans performed in 296 patients with suspected or known cardiac sarcoidosis were reviewed. Assessment of diagnostic quality, patterns of myocardial and extracardiac FDG uptake, concordance with other modalities cardiac MRI (CMR) and myocardial perfusion imaging (MPI) were assessed. Separate subgroup analysis of patients undergoing repeat 18 F-FDG PET-CT scans was conducted. Results Images of excellent diagnostic quality 18 F-FDG PET-CT were obtained in 365/397 studies (91.9%). Cardiac inflammation was identified in 226 and scans were normal in 139 patients. Extracardiac sarcoidosis was present in 230 (63%) patients. MPI was abnormal in 50/98 patients (51%) and CMR was abnormal in 88/126 patients (70%). PET and MPI findings showed concordance in 53% patients but not considered significant ( P = 0.78). High concordance with CMR was noted in 85.7% patients ( P < 0.001). For treatment monitoring, follow-up 18 F-FDG PET-CT scans accurately assessed disease status in 66/70 patients (94.2%). Conclusion We obtained excellent diagnostic quality of images in a high proportion of our patients (92%). Because of a high degree of concordance between 18 F-FDG PET-CT and CMR, we propose that either test can be used initially and the other test can be used in cases of clinical discordance. Interval 18 F-FDG PET-CT scans are immensely useful for treatment response monitoring.
Pant et al. (Thu,) studied this question.