Aortopulmonary window

Definition

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

Alternative Names

Aortopulmonary septal defect; Aortopulmonary fenestration

Causes, incidence, and risk factors

Normally, blood flows through the pulmonary artery into the lungs, where it picks up oxygen. Then the blood travels back to the heart and the aorta pumps it to 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 rushes into the pulmonary artery and too much blood flows through the lungs.

The condition occurs when the aorta and pulmonary artery do not divide normally as the baby develops in the womb. The hole connecting the two blood vessels sends extra blood through the lungs, causing high blood pressure in the lungs (a condition called pulmonary hypertension) and heart failure.

Usually the valves that control blood flow in these blood vessels are normal, but a hole above the valves lets the blood pass through. The bigger the defect, the more blood can enter the lung artery.

Aortopulmonary window is very rare. It accounts for only 0.1% of all congenital heart defects.

This condition can occur on its own or with other heart defects such as patent ductus arteriosus, tetralogy of Fallot, or pulmonary atresia. Fifty percent of patients usually have no other heart defects.

Symptoms

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

Signs and tests

The pediatrician will usually hear an abnormal heart sound (murmur) when listening to the child's heart with a stethoscope.

The doctor may order tests such as:

• A thin tube inserted into the arteries around the heart to view the heart and blood vessels (cardiac catheterization)
• Chest x-ray
• Echocardiogram
• MRI of the heart

Treatment

The condition usually requires open heart surgery to repair the defect. Surgery should be done as soon as possible after the diagnosis is made, usually 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.

Expectations (prognosis)

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

Complications

Delaying treatment can lead to complications such as:

• Congestive heart failure
• Death
• Pulmonary hypertension

Calling your health care provider

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

Prevention

There is no known way to prevent aortopulmonary window.

References

Park MK, Troxler RG. Park: Pediatric Cardiology for Practitioners. 4th ed. St. Louis, Mo: Mosby; 2002.

Jansen C. Surgical repair of aortopulmonary window: thirty-seven years of experience. Pediatr Cardiol, 2006;27:552-556.

Koh Su-Mei A, Ju-Le T. Large unrepaired aortopulmonary window--survival into the seventh decade. Echocardiography, 2007;24:71-73.