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.