Massive Mural Thrombus Masquerading as Myxoma

A 75-year-old Caucasian female with a past medical history including insulin-dependent diabetes mellitus, hypertension, and dyslipidemia, presented to the emergency room for having palpitations for three weeks. Echocardiography revealed a very large left atrial mass mimicking myxoma. Mass was excised and examined by pathology, revealing a mural thrombus. A mural thrombus is not an uncommon mass found in the left atrium. However, it does not often present symptomatically, strongly mimics an atrial myxoma on cardiac imaging, and has rarely ever been reported to be greater than seven centimeters in any dimension. We present a case of a 75-year-old Caucasian woman with a massive, symptomatic cardiac thrombus masquerading as a myxoma on imaging.