Fig. 1

Heart and thigh muscle MRI. The CMR results considered myocardial amyloidosis (involving bilateral, bilateral atria, atrial septum, and chest wall). Magnetic resonance cine sequences (A-D) showed significant left ventricular myocardial thickening (arrow) and reduced overall systolic motion. Cardiac perfusion (E, F) indicated annular low-signal filling defects in the subendocardial myocardium of the left ventricle after first perfusion, delayed enhancement in the subendocardial of both ventricle, dust-like enhancement in the walls of both atria and the atrial septum (arrow), and enhancement in the pericardium. MRI of the thigh shows diffuse muscle atrophy and fat deposition in both thigh muscles (arrow). Relaxed long T2(G) and short T1 (H) signals are seen in both thigh muscles and surrounding subcutaneous soft tissues