Beware of the LASP! A structure with thrombogenic potential.

The left atrial septal pouch (LASP) is a recently identified anatomical variant of the interatrial septum. It is the result of the incomplete fusion of septum primum and septum secundum and defined as a recessus communicating with the left atrium without interatrial shunt. Such anatomical feature has been suspected representing a potential thrombogenic source, but its actual role as risk factor for cryptogenic stroke still remains unclear. In this case report, we show two distinct thrombotic masses emerging from the LASP and its related areas.