Conclusions: Trans-esophageal echocardiography could be used to detect thrombus in mitral valve appendage which was missed in transthoracic echocardiography. Indicators of an increasing thrombus risk in mitral valve stenosis patients are (1) left atrial diameter ≥ 50 mm, (2) atrial fibrillation, (3) magnitude of left atrial spontaneous echo contrast, (4) Wilkins score > 9, (5) past history of stroke, (6) time from detection of disease, and (7) BMI.