Non-invasive diagnosis of a free-floating left atrial thrombus with emphasis on two-dimensional echocardiographic features.
Two-dimensional echocardiography permitted identification of a large free-floating left atrial thrombus in a patient with mitral stenosis. A specific pattern of motion afforded its recognition and differentiation from mural left atrial thrombosis and tumors. Phonocardiographic tracings revealed a non-ejection systolic click and opening snap. A gated blood pool scintigram disclosed a left atrial filling defect. Subsequent left atrial angiography and left atriotomy confirmed the non-invasive findings.