Rapid expansion of a left atrial myxoma caused by acute multiple internal hemorrhages: a case report and literature review

Fig. 1. Transthoracic echocardiogram in the parasternal long-axis view. A An image captured by the physician in the primary clinic two hours before admission to our hospital. An oval tumor (arrows) measuring about 25 × 35 mm in the left atrium was revealed. There was a 12-mm round hypoechoic area within the tumor. B An image taken upon admission to our hospital. A tumor (arrows) approximately 40 × 50 mm in size included a 20 × 30-mm-sized cystic lesion within it. The tumor and its internal cystic lesion were obviously expanded compared to those in the image captured in the primary clinic two hours earlier

Fig. 2. Transesophageal echocardiography images at 127 degrees. A At the insertion of the probe. B Just before establishing cardiopulmonary bypass. The tumor deformed rapidly morphologically during the operation. Flattening and lobing changes were remarkable. Small cystic formations just below the lobes were increased (arrows)

Fig. 3. Specimen. A The gross appearance showing myxomatous with multiple protruding hematomas. B Fixed specimen showing multiple tissue defects formed by intratumor hematomas (arrows). These hemorrhages were recognized as cystic lesions on echocardiography

Fig. 4. Hematoxylin and eosin-stained sections of the tumor. A Spindle-shaped cells and hyperchromatic nuclei segregated by abundant myxomatous stroma. Hemosiderin pigmentation and the presence of erythrocytes in the myxoid matrix indicated chronic and fresh bleeding (bar = 100 µm). B The myxomatous capsule right above the multiple hemorrhages was extremely thin (square) (bar = 2500 µm). The inset shows a thin capsule under high magnification (bar = 500 µm). Arrows indicate hemorrhages