What Is Patent Ductus Arteriosus?

One of the most common heart problems that babies are born with is a patent ductus arteriosus, or PDA. The ductus arteriosus is an important blood vessel in a fetus. It connects the two major arteries that go from the heart. It's supposed to close soon after birth. A patent ductus arteriosus (“patent” means open) is one that doesn’t close the way it should.

What is it?

In normal circulation, the right side of the heart pumps blood through the pulmonary arteries to the lungs. There, it picks up oxygen. The blood goes back to the left side of the heart, which pumps it through the aorta. From there, it goes to the rest of the body.

patent ductus arteriosusBabies don’t use their lungs before they’re born. They get oxygen from their mother’s blood. The ductus arteriosus is there to bypass the lungs. Instead, it sends blood straight from the pulmonary arteries to the aorta. If it doesn’t close, blood can flow backward from the aorta to the pulmonary artery. That sends too much blood into the lungs and left side of the heart. Pressure builds in the blood vessels and heart chambers. Over time, that can cause fluid buildup in the lungs and an enlarged heart.

Who’s at risk?

Doctors don’t know what causes PDA. It’s rare in full term-babies. But it’s fairly common in premature ones. It affects twice as many girls as boys, and it may run in families.

Moms who had rubella, or German measles, while they were pregnant are more likely to have a baby with PDA. It’s also more common in babies with conditions that that affect your genes, like Down syndrome. Babies who have it often have other heart problems too.

What are the symptoms?

Your baby may show no outward signs. But your doctor may notice that your baby’s heartbeat has a distinctive sound (murmur). If the opening is large, this condition affects how well your baby’s heart and lungs work. If it's serious, it can cause:

  • Heavy, fast breathing or shortness of breath
  • Trouble feeding and failure to gain weight
  • A fast, pounding heartbeat
  • Sweating when they’re active, as when feeding

Premature babies are more likely to have complications. They may not get enough oxygen, which leads to organ damage.


How is it diagnosed?

If your baby has symptoms, your doctor may send you to a children’s heart specialist. This doctor is called a pediatric cardiologist. He’ll give your baby tests to see how well their heart works. An echocardiogram is the best tool to diagnose this issue. It makes pictures of the heart and blood vessels with sound waves. It will show the size of the PDA and how much blood is flowing through it.

Should it be fixed?

If left untreated, a large PDA can damage the heart and lungs. It may also make you more likely to get an infection in the lining of the heart called endocarditis. But this is rare.

But they often close on their own, especially in premature babies. A very small one may never cause problems. Your pediatrician may tell you to keep an eye on it for a few weeks or months. If it causes heart or breathing problems, you'll need to treat it.

What’s the treatment?

Doctors fix them in one of three ways:

  • Medical: Drugs called non-steroidal anti-inflammatories (NSAIDs) can often close a PDA in a premature baby. They work to block a blood chemical that keeps it open.
  • Catheter closure: A surgeon may block the opening with a tiny metal coil or piece of mesh. He’ll insert a thin tube called a catheter into a large blood vessel in the baby’s groin. Then he'll thread it through to the heart. The coil or mesh goes through the tube into the ductus arteriosus to stop the blood flow. Your child may go home the same day.
  • Surgical ligation: A surgeon can also tie or clamp it closed. He'll make a cut in the left side of the chest between the ribs to reach the area. Your baby will likely stay in the hospital at least a couple of days. 

Doctors usually treat full-term babies or older children with the catheter procedure. Surgery may be best if the PDA is very large or your baby has other heart defects that need to be fixed.

For preemies, doctors usually try medicine first. If that doesn’t work, your doctor may suggest that you wait until your baby is big enough for a catheter procedure if they're OK otherwise.  


Life after PDA

Treatments are very effective. If your baby doesn’t have other health problems, you can expect them to eat and grow normally soon after it’s closed. Your child probably won’t have any limits on physical activity as they get older. This is true whether doctors fix it or if it's so small you choose to leave it alone. Talk to your doctor about how often your child will need a checkup. 

WebMD Medical Reference Reviewed by Hansa D. Bhargava, MD on August 30, 2019



Journal of Pediatric Pharmacology and Therapeutics: “Patent Ductus Arteriosus: An Overview.”

American Pediatric Surgical Association: “Patent Ductus Arteriosus.”

Circulation: “Patent Ductus Arteriosus.”

University of California San Francisco Pediatric Cardiothoracic Surgery: “Patent Ductus Arteriosus.”

American Heart Association: “Patent Ductus Arteriosus (PDA).”

Mayoclinic.org: “Patent ductus arteriosus (PDA).”

Pediatrics: “Patent Ductus Arteriosus in Preterm Infants.”

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