Failure of follow-up gallium single-photon emission computed tomography and fluorine-18-fluorodeoxyglucose positron emission tomography to predict the deterioration of a patient with cardiac sarcoidosis.

Although gallium-67-citrate (67Ga) scanning and single-photon emission computed tomography (SPECT) are useful in the assessment of disease activity in cardiac sarcoidosis, a patient with cardiac sarcoidosis in whom SPECT imaging with 67Ga failed to predict the deterioration in the clinical course is presented. A 53-year-old woman diagnosed with cardiac sarcidosis had 67Ga scanning and 67Ga SPECT, both of which showed abnormal high uptake. After treatment with corticosteroid, there was an apparent improvement in the 67Ga SPECT findings, and the dose of the corticosteroid was reduced. Subsequently, the disease activity of the cardiac sarcoidosis was thought to be well controlled, because abnormal uptake was not found on repeat 67Ga SPECT. However, 4 years after initial diagnosis, thinning at the basal ventricular septal wall and complete atrioventricular block were noted. Despite repeating the evaluation with 67Ga SPECT and additional fluorine-18-fluorodeoxyglucose positron emission tomography (18FDG PET) after discovering this progression, neither of these examinations showed any abnormality. Unfortunately, in this patient, the disease activity of cardiac sarcoidosis was underestimated by the diagnostic imaging modalities.