Interrupted aortic arch (IAA) is a heart defect someone is born with (congenital). This occurs when there is abnormal development of the heart and aorta during pregnancy.
The aorta is like the heart’s main highway, bringing blood out to the body. It takes oxygen-rich blood to the body through arteries that branch off like highway exits. But in this rare condition, the portion of the aorta that arches over the top of the heart is missing a section. This creates a roadblock that stops blood from getting to the lower part of a baby’s body.
This isn’t a problem during pregnancy. Before birth, a temporary blood vessel known as the ductus arteriosus, that connects the lung artery to the lower part of the aorta, carries blood to the lower half of a baby’s body. The ductus arteriosus usually closes in the first hours or days after birth. The aorta then takes over. But if the aortic arch is missing a section, the heart can’t get blood to the lower half of the body.