The ostium secundum allows continued shunting of blood from the right atrium to the left.

Persistence of the ostium secundum is the most common atrial septal defect.

Some embryologists postulate that the ostium secundum may be formed through programmed cell death.

Many patients with an ostium secundum that persists into adulthood will remain asymptomatic the duration of their lives.

An ostium secundum that persists at large size can be a source of atrial septal defects.

The foramen ovale is continuous with the ostium secundum, again providing for continued shunting of blood.

The ostium secundum atrial septal defect accounts for 7% of all congenital heart lesions.

The ostium secundum progressively enlarges and the size of the septum primum diminishes.

Ostium primum defects are less common than ostium secundum defects.

This method prevents the symptoms that are expected to accompany most ostium secundum atrial septal defects.

The ostium secundum provides communication between the atria after the ostium primum closes completely.

Subsequently, a second wall of tissue, the septum secundum, grows over the ostium secundum in the right atrium.

Ten to twenty percent of individuals with ostium secundum ASDs also have mitral valve prolapse.

Meanwhile, perforations appear in the superior part of the septum primum, forming the ostium secundum (i.e. "the second opening").

Once they fuse a new opening forms in the middle of the septum primum called the ostium secundum or foramen secundum.

The ostium secundum (or foramen secundum) is a foramen in the septum primum.

Ostium Secundum atrial septal defects are the most common atrial septal defects.

There are currently no drug therapies for ostium secundum atrial septal defects, although infective endocarditis is a postoperative concern.

Before it does so, bloodflow from the inferior vena cava wears down a portion of the septum primum, forming the ostium secundum.

Before the ostium primum is completely occluded, a second opening called the ostium secundum begins to form in the septum primum.

Bloodflow then only passes from the right to left atrium by way of a small passageway in the septum secundum and then through the ostium secundum.

If the ostium secundum ASD is accompanied by an acquired mitral valve stenosis, that is called Lutembacher's syndrome.

The septum secundum, semilunar in shape, grows downward from the upper wall of the atrium immediately to the right of the primary septum and ostium secundum.

Mitral regurgitation and mitral valve prolapse are common after the age of forty if the ostium secundum is not repaired by age twenty four, according to some sources.