18-FDG-PET imaging identified an intensely hypermetabolic focus in the interatrial septum, correlating with lipomatous hypertrophy of the interatrial septum on CT and MRI.
Case Report (n=1)
Recognizing that brown fat in lipomatous hypertrophy of the interatrial septum can be hypermetabolic on 18-FDG-PET helps avoid misdiagnosis of metastatic disease.
We present a 69-year-old female patient with a history of emphysema, rosacea, and breast cancer. The patient was in remission for 4 years until a 15-pound weight loss prompted further evaluation with a computed tomography of the chest, abdomen, and pelvis, cardiac magnetic resonance imaging, as well as an 18-FDG-PET scan to evaluate for metastatic disease and potential cardiac abnormalities. There was an intensely hypermetabolic bilobed focus within the region of the interatrial septum, correlating with the patient's lipomatous hypertrophy of the interatrial septum (LHIS), which was identified on computed tomography and magnetic resonance imaging. LHIS is a relatively uncommon cardiac finding characterized by excessive deposition of adipocytes with varying quantities of brown fat. Brown fat in LHIS may be hypermetabolic on 18-FDG-PET examinations, and familiarity with the prevalence and features of LHIS will avoid misdiagnosis of metastatic disease.
Klein et al. (2010) conducted a case report in Lipomatous hypertrophy of the interatrial septum (n=1). 18-FDG-PET, MRI, and CT imaging was evaluated on Identification of cardiac abnormalities. 18-FDG-PET imaging identified an intensely hypermetabolic focus in the interatrial septum, correlating with lipomatous hypertrophy of the interatrial septum on CT and MRI.