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Patent Ductus Arteriosus


The Manual's Editorial Staff

Reviewed/Revised May 2022 | Modified Sep 2022
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The aorta moves blood away from the heart to the rest of the body. The pulmonary artery moves blood from the heart to the lungs.

Before birth and for a few days after birth, the pulmonary artery and the aorta are connected by a short blood vessel called the ductus arteriosus.

  • Because a fetus doesn't breathe, very little blood needs to go to its lungs

  • The fetus has a ductus arteriosus so blood can bypass the lungs

After birth, the ductus needs to close quickly so blood can flow normally, first through the lungs and then to the body.

What is patent ductus arteriosus (PDA)?

Patent is a medical term that means "open." In patent ductus arteriosus (PDA), the ductus arteriosus doesn't close.

  • Premature babies are more likely to have PDA

  • Often there aren't any symptoms, but a doctor listening with a stethoscope may hear a heart murmur (an unusual sound between heartbeats)

  • Doctors treat PDA with medicine and sometimes surgery

  • Babies with PDA have a higher than normal chance of getting a heart infection

Patent Ductus Arteriosus: Failure to Close

The ductus arteriosus is a blood vessel that connects the pulmonary artery and the aorta. In the fetus, it enables blood to bypass the lungs. The fetus does not breathe air, and thus blood does not need to pass through the lungs to be oxygenated. After birth, blood does need to be oxygenated in the lungs, and normally the ductus arteriosus closes quickly, usually within days up to 2 weeks.

In patent ductus arteriosus, this connection does not close, allowing some oxygenated blood, intended for the body, to return to the lungs. As a result, the blood vessels in the lungs may be overloaded and the body may not receive enough oxygenated blood.

Patent Ductus Arteriosus: Failure to Close

What causes PDA?

What are the symptoms of PDA?

If the PDA is small, a baby may not have any symptoms. If the PDA is larger, your baby may have:

  • Fast breathing

  • Trouble breathing

  • Low blood pressure

  • Trouble feeding

  • Slow or poor growth

How can doctors tell if my baby has PDA?

How do doctors treat PDA?

Treatment depends on:

  • The size of the PDA

  • How premature the baby is

  • What symptoms the baby has

Sometimes a small PDA will close on its own. This usually happens before a baby is 1 year old. If doctors need to treat your baby's PDA, they may:

  • Give your baby certain medicines that can help close the ductus

  • Place a long, thin tube (catheter) in the baby's heart and use a device to close the ductus

  • If the PDA is unusually large, do surgery to close the ductus

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