Left atrial appendage myxoma masquerading as left atrial appendage thrombus

Disappearing "Myxoma": Left Atrial Thrombus Masquerading as a Myxoma

Intracardiac masses can be challenging to differentiate by echocardiography. We present a case of several intracardiac masses with echocardiographic features of both thrombi and myxoma in a patient with heart failure symptoms. The masses were confirmed to be thrombi after complete resolution on repeat echocardiography following anticoagulation. Echocardiography complements the history and physical exams in diagnosing intracardiac masses but may present a diagnostic challenge when features are not pathognomonic. Follow up imaging after anticoagulation should be standard of care to avoid unnecessary surgeries when the diagnosis of a cardiac mass is uncertain.

Left atrial appendage myxofibrosarcoma: A rare masquerader of myxoma and thrombus-"all that glitters is not gold"

Left atrial appendage mass can occasionally pose a serious challenge to physicians to identify the nature of the mass with the aid of imaging techniques. We present a case of 67-year-old man, who was evaluated for suspected left atria myxoma. Transesophageal echocardiography revealed a heterogeneous density originating from left atrial appendage, thought to be most consistent with a myxoma. Cardiac magnetic resonance imaging, uncharacteristically, gave an equivocal picture, suggesting the mass to be a myxoma on initial imaging and a thrombus with evidence of liquefaction necrosis following postcontrast enhancement. Surprisingly, histopathology of the mass following its surgical excision yielded a rare diagnosis of myxofibrosarcoma.

Left atrial appendage mass: is it always a thrombus?

Myxoma is the most common benign tumor of the heart, but it is very rare for it to originate from the left atrial appendage. Distinguishing between a mass, a thrombus, and a tumor in the body of the left atrium with preoperative transthoracic or transesophageal echocardiography is very difficult, even more so in patients with mitral valve disease and chronic atrial fibrillation. A 50-year-old male patient was admitted for surgery with the diagnosis of mitral stenosis and chronic atrial fibrillation. Transesophageal echocardiography demonstrated a mass attached to the wall of the left atrial appendage. Histopathological examination of the mass showed an image compatible with a myxoma. We hereby describe a case of a left atrial appendage myxoma mimicking a left atrial appendage thrombus.