Associations of patent foramen ovale (PFO)

Patent foramen ovale (PFO) is a small defect in the inter atrial septum in the region of the fossa ovalis, between the layers contributed by the septum primum and septum secundum. Due to the specific direction of the valvular opening, blood can shunt from the right atrium to left atrium, especially during a Valsalva maneuver. Common associations of a PFO are the Eustachian valve, Chiari network and an atrial septal aneurysm. Eustachian valve is at the opening of the inferior vena cava into the right atrium and tends to direct the inferior vena caval blood across the patent foramen ovale. It is a remnant of the embryonic right valve of the sinus venosus. Chiari network, also a remnant of the right valve of the sinus venosus, is a network of filamentous structures sometimes seen in the right atrium. Atrial septal aneurysm is located in the fossa ovalis region where the septum primum overlies the septum secundum.
Source: Cardiophile MD - Category: Cardiology Authors: Tags: General Cardiology Chiari network Eustachian valve foramen ovale fossa ovalis patent foramen ovale PFO remnant of the embryonic right valve of the sinus venosus septum primum septum secundum Valsalva maneuver Source Type: blogs