Radiological signs of a left atrial aneurysm.

We report a case of an acquired mid-sized extrapericardial aneurysm in the area of the left atrial appendage and demonstrate the diagnostic impact of several imaging methods. Chest radiography gave a hint to the diagnosis with a bulky mass of soft tissue density appearing adjacent to the left atrial appendage. Transthoracic as well as transesophageal echocardiography missed the origin of the aneurysm. Magnetic resonance imaging helped to establish the diagnosis with use of a coronal imaging plane. No contrast agent was necessary. Thus, the combination of chest X-ray and MRI provided excellent support for patient management.