Floating left atrial mass in a patient with mitral stenosis.

Mobile masses within the left atrial cavity are commonly caused by organized thrombi or left atrial myxoma. The use of transesophageal echocardiography has provided means for differentiation between the 2 conditions. We report a case of a left atrial mass in a female patient who presented with mitral stenosis and atrial fibrillation, and was diagnosed by transthoracic echocardiography (TTE).