Aortopulmonary window is a rare heart defect in which there is a hole connecting the major artery taking blood from the heart to the body (the aorta) and the one taking blood from the heart to the lungs (pulmonary artery). The condition is congenital, which means it is present at birth.

Aortopulmonary septal defect; Aortopulmonary fenestration; Congenital heart defect - aortopulmonary window; Birth defect heart - aortopulmonary window

Normally, blood flows through the pulmonary artery into the lungs, where it picks up oxygen. Then the blood travels back to the heart and is pumped to the aorta and the rest of the body.

Babies with an aortopulmonary window have a hole in between the aorta and pulmonary artery. Because of this hole, blood from the aorta flows into the pulmonary artery, and as a result too much blood flows to the lungs. This causes high blood pressure in the lungs (a condition called pulmonary hypertension) and congestive heart failure. The bigger the defect, the more blood that is able to enter the pulmonary artery.

The condition occurs when the aorta and pulmonary artery do not divide normally as the baby develops in the womb.

Aortopulmonary window is very rare. It accounts for less than 1% of all congenital heart defects.

This condition can occur on its own or with other heart defects such as:

• Tetralogy of Fallot
• Pulmonary atresia
• Truncus arteriosus
• Atrial septal defect
• Patent ductus arteriosus
• Interrupted aortic arch

Fifty percent of people usually have no other heart defects.

If the defect is small, it may not cause any symptoms. However, most defects are large.

Symptoms can include:

• Delayed growth
• Heart failure
• Irritability
• Poor eating and lack of weight gain
• Rapid breathing
• Rapid heartbeat
• Respiratory infections

The condition usually requires open heart surgery to repair the defect. Surgery should be done as soon as possible after the diagnosis is made. In most cases, this is when the child is still a newborn.

During the procedure, a heart-lung machine takes over for the child's heart. The surgeon opens the aorta and closes the defect with a patch made either from a piece of the sac that encloses the heart (the pericardium) or a man-made material.

Surgery to correct aortopulmonary window is successful in most cases. If the defect is treated quickly, the child should not have any lasting effects.

Delaying treatment can lead to complications such as:

• Congestive heart failure
• Pulmonary hypertension or Eisenmenger syndrome
• Death

Call your provider if your child has symptoms of aortopulmonary window. The sooner this condition is diagnosed and treated, the better the child's prognosis.

There is no known way to prevent aortopulmonary window.

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