Is it really fat? Ask a T1-map

A 67-year-old woman initially presented with dyspnoea. Echocardiography demonstrated an inter-atrial mass. Cardiovascular magnetic resonance (CMR) showed a well-marginated mass (35 mm × 45 mm) in the inter-atrial septum (IAS) sparing the fossa ovalis, extending to the posterior right atrial wall. The mass had high signal intensity on T1-weighted images ( Panels A and B , arrows) consistent with fat, which attenuated on fat-suppression imaging ( Panels C and …