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.	Majority of patients are asymptomatic	TEE TTE TCD	Appearance of at least 3 micro-bubbles in the left atrium within three cardiac cycles after the complete opacification of the right atrium		Percutaneous closure Anticoagulants Antiplatelets	Paradoxical embolism Migraine with aura Decompression sickness in divers Platypnea-orthodeoxia syndrome
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.	Continuous left-to-right shunt	Infants may experience failure to thrive, tachypnea, recurrent respiratory infections, heart failure Commonly asymptomatic during childhood and adolescence Adults with large shunts may become symptomatic in the fourth decade presenting with fatigue, exercise intolerance, palpitations, syncope, and shortness of breath. Smaller shunts may become symptomatic in the third decade			Soft, systolic ejection murmur with a wide, fixed splitting of S2 heard in the second right intercostal space		Right sided heart failure Peripheral edema Eisenmenger syndrome (cyanosis) Paradoxical emboli Pulmonary hypertension
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)