<div>4</div><div><b>FIGURE 1</b> Transthoracic echocardiography (TTE)—modified apical
4-chambers view: A, there is unremarkable 8 months ago. B, a marked
hypoechogenic neoplasm (red arrows) with a hyperechoic capsule attached
to the right atrium (RA) wall, and the neoplasm breaks into the
tricuspid valve during diastole.</div><div><b>FIGURE 2</b> TTE- modified parasternal short-axis view: The
neoplasm (red arrows) returns to the right atrium during systole,
causing moderate regurgitation of the tricuspid valve (yellow
arrowhead).</div><div><b>FIGURE 3</b> Contrast-enhanced computerized tomography (CT) shows a
low-density mass with little enhancement in the right atrium (red
arrows)</div><div><b>FIGURE 4</b> Histopathological examination showing endothelial
cells and communicating dilated lumens. Hematoxylin and eosin staining,
original magnification ×200.</div>