The potential role of the left atrial septal pouch in cryptogenic stroke.

The left atrial septal pouch (LASP) is an anatomic variant of the atrial septum that forms a blind-ending pouch, communicating exclusively with the left atrium (LA). Case reports have demonstrated thrombus within LASP and in the setting of cryptogenic stroke. Initial epidemiologic results are mixed, one study showing and others not showing an association between LASP and cryptogenic stroke. Additional investigation should take place to determine the clinical significance of LASP and what interventions are required to prevent ischemic stroke in at-risk individuals.