Rare case of cardiac hemangioma causing massive pericardial effusion: can a left atrial tumor produce pericardial effusion?

A 35-year-old woman presented to the emergency room with a 2-month history of general malaise and anasarca. The chest x-ray showed cardiomegaly, and transthoracic echocar-diography revealed massive pericardial effusion leading to cardiac tamponade (Figure 1A and 1B). Immediately, 1400 mL pericardial effusion (yellow exudate) was removed by needle pericardiocentesis. After the procedure, transthoracic echocar-diography showed an immobile, heterogeneous tumor in the left atrium (LA) (Figure 1C and Movie I in the online-only Data Supplement). Cardiac computed tomography revealed a well-circum-scribed tumor located in the LA near the origin of the left pulmonary veins (Figure 1D and 1E and Movies II and III in the online-only Data Supplement). Cardiac magnetic resonance imaging showed that the tumor was isointense on T1-weighted images (Figure 1F) and hyperintense on T2-weighted images (Figure 1G). Coronary angiography revealed " tumor blush " with feeding arteries from the left circumflex artery (Figure 1H and Movie IV in the online-only Data Supplement), indicating hypervascularity. Multimodality imaging (computed tomography, cardiac magnetic resonance, and echocardiography) indicated that the tumor was an LA intracavitary mass originating from the LA wall. However, an intracavitary tumor cannot intrinsically produce pericardial effusion (the tumor must be located in the pericardial space to produce pericardial effusion). Therefore, the tumor was thought to invade the epicardium, and the differential diagnosis of hypervascular tumor included not only benign hypervascular tumor such as myxoma and hemangioma but also malignant tumor such as angiosarcoma. After these preoperative examinations, the tumor was excised, and the patient's recovery was uneventful. Initially, the tumor was considered to be myxoma because of its edem-atous, semitransparent appearance on macroscopic examination (Figure 2A). However, histopathology revealed that the tumor was a cardiac hemangioma (cavernous-capillary type) originating from the LA myocardium (Figure 2B–2E). Cardiac hemangiomas are usually asymptomatic, but depending on the location of the tumor, they have been reported to cause arrhythmia, heart failure, outflow tract obstruction, angina, and pericardial effusion in rare cases. 1 In our case, the tumor was initially recognized as an intracavi-tary mass, and it was not clear why the intracavitary tumor produced pericardial effusion. However, histology disclosed that the tumor extended to the epicardium and was located in the pericardial space, resulting in massive pericardial effu-sion. The tumor also forced the LA myocardium toward the LA cavity (Figure 2B and 2C), and this is why we misrecog-nized the extracavitary tumor as intracavitary. Disclosures None.