Myocardial metastasis within lipomatous hypertrophy of the interatrial septum

Abstract

A 74-year-old lady with lipomatous hypertrophy of the interatrial septum presented with symptomatic anemia. Imaging revealed a new diagnosis of metastatic cancer of presumed lung origin, with a new soft tissue myocardial lesion adjacent to the right atrium within the region of lipomatous hypertrophy. This was favored to represent a myocardial metastasis within concurrent lipomatous hypertrophy of the interatrial septum.

Keywords: Cardiac mass; Computed tomography; Lipomatous hypertrophy of interatrial septum; Lung cancer; Myocardial metastasis.

Fig. 1

Computed tomography scans demonstrate the presence of a spiculated right middle lobe pulmonary parenchymal mass (black arrow, A) suspicious of a primary lung malignancy. There are enlarged mediastinal necrotic lymph nodes (white arrow, B) as well as multiple hypodense hepatic lesions (white arrow, C), favored to represent nodal and hepatic metastases. There is a myocardial soft tissue lesion seen adjacent to the right atrium within fatty tissue (white arrow, D).

Fig. 2

Axial noncontrast chest CT from 1 year prior demonstrates lipomatous hypertrophy of the interatrial septum (white arrow, A). Side-by-side comparison to the axial contrast-enhanced chest CT 1 year after demonstrates interval development of the new myocardial soft tissue lesion within the pre-existing LHIS (white arrow, B).