Sandbox: Ifeoma

Diseases	Anatomy	Shunt	Symptoms	Diagnosis	Imaging findings	Physical examination	Treatment	Complications	Additional findings
Patent foramen ovale	Failure of fusion of the septum primum and septum secundum leading to a flap valve opening.	*Right-to-left shunt *More prominent with increased right atrial pressure.
Atrial septal defect	*Ostium secundum defect: Failure of the septum secundum to occlude the ostium secundum. *Ostium primum defect: Failure of the ostium primum to fuse with the endocardial cushions. *Superior sinus venosus defect: The orifice of the superior vena cava overrides the atrial septum above the fossa ovalis. *Inferior sinus venosus defect: The orifice of the inferior vena cava overrides the left and right atrium.
Coronary sinus defect
Pulmonary ateriovenous fistula

• Patent foramen ovale may be classified anatomically according to the shape of the tunnel using a real time 3-dimensional transesophageal echocardiography (RT3D-TEE). It is classified based on the minimum overlap of the septum primum and septum secundum under valsalva maneuver.
• The table below shows the different tunnel types:

Patent Foramen Ovale Tunnel Type	Description
Type 1	Complete overlap
Type 2	Partial overlap (≧ 4 mm)
Type 3	Little or zero overlap (< 3 mm)

Diseases	Anatomy	Shunt	Symptoms	Physical Education	Diagnosis	Treatment	Complications
Type 1	Complete overlap
Type 2	Partial overlap (≧ 4 mm)
Type 3	Little or zero overlap (< 3 mm)