Definition

A patent ductus arteriosus (PDA) is a type of congenital (present at birth) heart problem.

The pulmonary artery is a blood vessel that moves blood from the heart to the lungs. The aorta is a blood vessel that moves blood from the heart out to the rest of the body. Before birth, the baby gets its oxygen from the mother, so its lungs are not used. The ductus arteriosus is a small passageway between the pulmonary artery and the aorta that allows blood in the baby to bypass the unused lungs and carry oxygen to the other organs.

In most babies, the ductus arteriosus closes within a few hours of birth. This is normal. When the ductus arteriosus stays open, blood travels in the wrong direction between the aorta and pulmonary artery. This causes too much blood to flow through the lungs.

Causes

In most cases, the cause is not known. However, in a small number of cases, PDA could be caused by exposure during pregnancy to a viral infection, rubella, drugs, or alcohol. In some children, congenital heart disease, including PDA, may be caused by genetic factors.

Risk Factors

Premature babies are at increased risk, although a patent ductus often closes when the baby becomes more mature. PDA may be more common in female babies or babies born at high altitudes. In most cases occurring in full term babies, there are no known risk factors for PDA.

Symptoms

Symptoms vary with the size of the ductus and the amount of blood that flows through it. If the ductus is small, there may be no symptoms. When symptoms occur, they include:

• Rapid breathing
• Labored breathing
• Getting tired quickly
• Poor growth

In some babies, symptoms may not occur until a few weeks or months after birth. Occasionally, PDA is not found until a much later age.

Even when there are no symptoms, the baby is at higher risk for a serious infection called endocarditis.

Diagnosis

A physical exam will be done. A PDA causes a heart murmur because of the blood flow from the aorta to the pulmonary artery. This characteristic sound can be heard during a physical exam. In premature babies, this heart murmur—accompanied by heart failure —is enough to diagnose PDA.

Images may be taken of your child’s chest. This can be done with:

• Chest x-ray
• Echocardiogram

Treatment

In some cases, a child may be monitored to see if the PDA will close on its own with time. Other conditions will be managed.

Prevention

There are no guidelines for preventing PDAs.

Children’s Heart Institute http://www.childrenheartinstitute.org

The College of Family Physicians of Canada http://www.cfpc.ca

Patent ductus arteriosus. Boston Children’s Hospital website. Available at:
http://www.childrenshospital.org/health-topics/conditions/patent-ductus-arteriosus
Accessed November 5, 2014.

Patent ductus arteriosus. Kids Health—Nemours Foundation website. Available at:
http://kidshealth.org/parent/medical/heart/patent_ductus_arteriosus.html
Updated February 2012. Accessed November 5, 2014.

Patent ductus arteriosus (PDA). American Heart Association website. Available at:
http://www.heart.org/HEARTORG/Conditions/CongenitalHeartDefects/AboutCongenitalHeartDefects/Patent-Ductus-Arteriosus-PDA_UCM_307032_Article.jsp
Updated May 6, 2014. Accessed November 5, 2014.

What is patent ductus arteriosus? National Heart, Lung, and Blood Institute website. Available at:
http://www.nhlbi.nih.gov/health/health-topics/topics/pda/
Updated September 26, 2011. Accessed November 5, 2014.