A rare case of nonobstructive membrane of the left atrial appendage.

The left atrial appendage (LAA) is a blind-ending, complex structure distinct from the body of the left atrium and is sometimes regarded as a minor extension of the atrium. However, it should routinely be evaluated as part of a transesophageal echocardiographic examination. In this study we describe the presence of a nonobstructive membrane traversing the cavity of the LAA, found incidentally on transesophageal echocardiography.