A patient having mitral stenosis with chronic atrial fibrillation, large left atrium, and spontaneous echo contrast is expected to have clot in LA or LAA. TEE is more sensitive to detect thrombus in LA and LAA than transthoracic echocardiography. However, false-negative results can still occur due to multilobed LAA, and a thrombus can be potentially missed. [ABSTRACT FROM AUTHOR]