Lipomatous hypertrophy of the atrial septum by 18F-FDG PET/CT

*Correspondence: Francisco J. García-Gómez E-mail: javier191185@gmail.com Available online: 20-12-2022 Rev Colomb Cardiol. 2022;29(Sup 4):72-73 www.rccardiologia.com Date of reception: 17-07-2020 Date of acceptance: 03-06-2021 DOI: 10.24875/RCCAR.M22000190 0120-5633 / © 2021 Sociedad Colombiana de Cardiología y Cirugía Cardiovascular. Published by Permanyer. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Lipomatous hypertrophy of the interatrial septum (LHIS) is a benign but less recognized pathology of the heart caused by unencapsulated mature fat cell infiltrating the myocardial fibers of the interatrial septum, sparing the fossa ovalis. However, in some cases LHIS could cause complications by a severe, symptomatic, and disabling dynamic left ventricular outflow tract obstruction, superior vena cava syndrome, pericardial effusion, supraventricular arrhythmias or sudden death. Its diagnosis is usually incidental, even being missdiagnosed. LHIS has a prevalence of 2.2% while appearing in approximately 1% of autopsies. The etiology is still unknown, but seems the presence of fetal brown fat amid the matured fat cells contributes to the 18F-FDG uptake, which is greater than in the subcutaneous fat of the chest wall, because the former is metabolically active. In a prospective study over a 2-year period for cancer screening using 18F-fluorodeoxyglucose PET/ CT, LHIS was observed in 11 patients and focal increased radiotracer uptake was showed in nine patients (82%). The uptake (SUV) of LHIS was 1.6-6.1 times greater than the mediastinum blood pool.