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FIGURE 1 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.
FIGURE 2 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).
FIGURE 3 Contrast-enhanced computerized tomography (CT) shows a low-density mass with little enhancement in the right atrium (red arrows)
FIGURE 4 Histopathological examination showing endothelial cells and communicating dilated lumens. Hematoxylin and eosin staining, original magnification ×200.