Patent Ductus Arteriosus (PDA)

What is PDA?

Patent ductus arteriosus (PDA) is a heart defect found in the days or weeks after birth. The ductus arteriosus is a normal part of fetal blood circulation before a baby is born. It’s an extra blood vessel that connects 2 arteries: the pulmonary artery and the aorta. The pulmonary artery carries blood from the heart to the lungs. The aorta carries blood from the heart to the body. Before birth, the ductus arteriosus lets blood go around (bypass) the lungs. This is because the baby gets oxygen from the mother.

All babies are born with this opening between the aorta and the pulmonary artery. But it often closes on its own shortly after birth, once the baby breathes on its own. If it stays open (patent), it is called patent ductus arteriosus. With PDA, extra blood flows to the lungs. If the PDA is large, too much blood goes to the lungs. The blood vessels and the lungs have to work much harder to handle the extra blood. This can lead to fluid buildup in the lungs. The baby can have a harder time breathing and feeding.

PDA occurs twice as often in girls as in boys.

What causes PDA?

Experts don't know exactly why PDA occurs. It is more common in babies born prematurely. PDA can also occur along with other heart defects.

What are the symptoms of PDA?

The size of the opening between the aorta and the pulmonary artery will affect symptoms. If your baby has a small opening, he or she may not have symptoms. If your baby has a larger opening, he or she may have symptoms. These are the most common symptoms of PDA:

  • Skin turns a blue color from not getting enough oxygen (cyanosis)

  • Very tired

  • Fast or hard breathing

  • Trouble feeding, or tiredness while feeding

  • Infections

  • Poor weight gain

  • In older children, trouble doing activities

The symptoms of PDA can seem like other health conditions. Have your child see his or her healthcare provider for a diagnosis.

How is PDA diagnosed?

The healthcare provider will ask about your baby’s symptoms and health history. He or she will give your baby a physical exam. The provider may have heard a heart murmur or found other symptoms during an exam. The provider may refer your baby to a pediatric cardiologist. This is a doctor with special training to diagnose and treat heart problems in children.

The cardiologist will also check your baby, and listen to the heart and lungs. The details about the heart murmur will help the provider make the diagnosis. Your baby may need tests, such as:

  • Chest X-ray. A chest X-ray may show an enlarged heart and lung changes in a baby with PDA.

  • Electrocardiogram (ECG). An ECG checks the electrical activity of the heart. It shows abnormal rhythms (arrhythmias) and heart muscle stress.

  • Echocardiogram (echo). An echo uses sound waves to make a moving picture of the heart and heart valves. An echo shows the blood flow pattern through the PDA. It also shows how large the opening is, and how much blood is passing through it. An echo is the most common way that a PDA is diagnosed.

  • Cardiac catheterization. Typically a catheterization is done to possibly treat a PDA, not diagnose it.

How is PDA treated?

Treatment will depend on your child’s symptoms, age, and general health. It will also depend on how severe the condition is.

A small PDA may close on its own as your child grows. A PDA that causes symptoms will need to be treated with medicine, cardiac catheterization, or surgery. The cardiologist will check from time to time to see if the PDA is closing on its own. If a PDA does not close, it will be fixed to prevent lung problems. Treatment may include the following.


Your baby may need medicines help the heart work better.

  • In premature infants, the medicine indomethacin may help close the PDA. It is given by IV (intravenously). Indomethacin stimulates the muscles inside the PDA to tighten. This closes the connection. Your child's cardiologist can answer any questions you may have about this treatment.

  • Some babies may need medicine to help the heart and lungs work better. Sometimes a baby may need medicine such as diuretics (water pills). Diuretics help the kidneys remove extra fluid from the body. This may be needed when the heart is not working well. Or it may be needed if the blood vessels in the lungs have to make room for more blood flow, as with a PDA.


Most infants with PDA eat and grow normally. Some premature infants or those infants with large PDAs may get tired when feeding. They may not be able to eat enough to gain weight. Nutrition choices include:

  • High-calorie supplements. Special nutritional supplements may be added to formula or pumped breastmilk to increase the number of calories. Your baby can drink less and still have enough calories to grow correctly.

  • Supplemental tube feedings. Supplemental feedings are given through a small, flexible tube. The tube passes through the nose, down the food pipe (esophagus), and into the stomach. The feedings can either be added to or take the place of bottle-feedings. Infants who can drink part of their bottles, but not all, may be fed the rest through the feeding tube. Babies who are too tired to bottle-feed may get all of their formula or breastmilk through the feeding tube.

Cardiac catheterization (therapeutic cardiac cath)

For this test, your baby will be given medicine to relax (sedation). The healthcare provider will put a thin, flexible tube (catheter) into a blood vessel in the groin. He or she will guide it through the large blood vessel in the groin to the area of the PDA. The catheter will be placed in the PDA. Dye may be injected at this time to help the provider put the catheter in the right place. A coil or closure device which is attached to the catheter will then be placed in the PDA. This will stop blood from flowing through the PDA. Once the coil or device is in the correct position, it will be released from the catheter. Then the catheter will be removed Typically this method is used if a child:

  • Is older than 6 months

  • Is at least 22 pounds

  • Has defects that are not too large



Surgery can close PDAs. Surgical closure is often advised for babies younger than 6 months who have large defects and symptoms such as poor weight gain and fast breathing. For babies who don't have symptoms, any surgery may be delayed until after age 6 to 12 months. Your child's cardiologist will advise when the surgery should be done. It is done under general anesthesia so you child will be asleep. Surgery closes the PDA with stitches or clips. This stops the extra blood from getting into the lungs. Premature babies must have this surgery.

What are possible complications of PDA?

If not treated, PDA may lead to long-term lung damage. It can also damage the blood vessels in the lungs. But this is not common because most children will have been treated for their PDA before the lungs and blood vessels get damaged.

Living with PDA

If your baby is discharged home before having a repair procedure, you will be shown how to feed and give medicine to your baby. You will also be taught what symptoms to report to your child's healthcare provider.

When your child is discharged after the PDA repair, you may give pain medicine such as acetaminophen or ibuprofen to keep your child comfortable. Your child's cardiac team will talk about pain control before your child goes home.

Often infants who fed poorly before surgery have more energy once they recover. They begin to eat better and gain weight faster.

Within a few weeks after surgery, older children are often fully recovered and able to do normal activities.

You will get other instructions from your child's cardiac team and the hospital staff.

In premature infants, the outlook after PDA surgical repair depends on gestational age and overall health.

In children born full-term, early diagnosis and repair of PDA lets them live normal, healthy lives. Activity levels, appetite, and growth should return to normal. Your child's cardiologist may advise that your child take antibiotics to prevent infection in the heart lining and valves (bacterial endocarditis).

In children with large PDAs diagnosed very late or never repaired, the outlook is uncertain. They are at risk for increased blood pressure in the blood vessels of the lungs (pulmonary hypertension). These children should get follow-up at a care center that specializes in congenital heart disease.

Talk with your child's cardiologist about your child’s outlook.

When should I call my child's healthcare provider?

Call your child's healthcare provider if your child's symptoms get worse, or if new symptoms develop, particularly breathing or feeding problems.

Key points about PDA

  • PDA is a heart defect found in the days or weeks after birth.

  • It occurs because a normal fetal connection between the aorta and the pulmonary artery does not close as it should after birth.

  • PDA happens most often in premature infants. It often occurs with other congenital heart defects.

  • A small PDA may close on its own as your child grows. If it is large or does not close, your child will need a repair procedure.

  • An infant or child with PDA will be cared for by a pediatric cardiologist.

  • Most children with a fixed PDA will live normal, healthy lives.

Next steps

Tips to help you get the most from a visit to your child’s healthcare provider:

  • Know the reason for the visit and what you want to happen.

  • Before your visit, write down questions you want answered.

  • At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you for your child.

  • Know why a new medicine or treatment is prescribed and how it will help your child. Also know what the side effects are.

  • Ask if your child’s condition can be treated in other ways.

  • Know why a test or procedure is recommended and what the results could mean.

  • Know what to expect if your child does not take the medicine or have the test or procedure.

  • If your child has a follow-up appointment, write down the date, time, and purpose for that visit.

  • Know how you can contact your child’s provider after office hours. This is important if your child becomes ill and you have questions or need advice.