Patent Foramen Ovale Embryology, Anatomy, and Physiology.

Patent foramen ovale (PFO) is a common finding in the general population but may lead to serious conditions such as stroke from paradoxical embolism and platypnea orthodeoxia. A thorough understanding of the interatrial septal anatomy along with its assessment by different imaging modalities is critical in performing safe transcatheter PFO closure. Investigating the anatomy and right heart to left heart flows using transesophageal echocardiography or intracardiac echocardiography imaging must be done before undertaking closure of a PFO.