Atrial fibrillation is an important factor associated with left atrium (LA) enlargement and thrombus formation in the LA appendage. Transesophageal echocardiography is the procedure of choice for assessment of dimension of the LA, as well as thrombus detection in the LA cavity or LA appendage. It can detect thrombi with a high degree of sensitivity and specificity varying from 93% to 100%. Cardiac CT represents a gold standard for the assessment of anatomy of the LA complex. The mean CT sensitivity for identifying thrombus in the LA was 81% and the mean specificity 90%. Because of the high spatial resolution and the excellent myocardial border detection magnetic resonance imaging (MRI) is considered the most accurate technique for the non-invasive assessment of atrial volumes. Cardiac magnetic resonance imaging helps in tissue characterization of various intra-atrial masses and thus differentiation between cardiac tumors and thrombi. Both CMR and cardiac CT currently represent very important imaging modalities used for the comprehensive evaluation of the LA. (1-3)

In our work we show a small series of patients with suspected mass in the LA appendage on the transesophageal ultrasound in which a cardiac MSCT and/or cardiac MRI is performed.