Diagnostic value of cardiac magnetic resonance and fluorodeoxyglucose-positron emission tomography for cardiac sarcoidosis with previous myocardial infarction A case report

Rationale: Diagnostic difficulty due to overlapped clinical findings exists in cardiac sarcoidosis (CS) patients who also have coronary artery disease. Since cardiac magnetic resonance (CMR) and fluorodeoxyglucose-positron emission tomography (FDG-PET) evaluate different pathological processes, that is, fibrosis and inflammation respectively, the combination may be useful in such a case. Patient concerns: A 77-year-old man was admitted due to heart failure and advanced atrioventricular block who was previously diagnosed with cutaneous sarcoidosis and old myocardial infarction (MI) with angiographical evidence. Diagnosis: He was finally diagnosed with CS using CMR and FDG-PET by specifying the myocardial lesion of sarcoidosis. Interventions: He was treated with corticosteroids based on the diagnosis. Outcomes: The focal high uptake on FDG-PET was improved and he had a better clinical course without further cardiac events. Lessons: Our case suggests that CMR and FDG-PET are complimentary, and the combination is useful for diagnosis of CS, particularly in cases that have previous MI.