Misleading aspect of left atrial appendage membrane: an incidental echocardiographic finding

The left atrial appendage (LAA) is a blind-ending, muscular extension of the left atrium and is of clinical importance in as much as the LAA is a place where a thrombus could be formed when the left atrial (LA) function decreases (1). However, it should routinely be analyzed as part of a transesophageal echocardiographic (TEE) examination (2). The LAA cavity might very rarely have membranes. Indeed, only less than ten cases of a membrane involving the LAA have been described in the literature. The origin of membranes involving the LAA is not clear. The most likely explanation for the origin of these membranes would appear to be a congenital anatomic variation (3).