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. All babies are born with this opening between the aorta and the pulmonary artery, but it usually closes on its own shortly after birth. If it stays open, it is called patent ductus arteriosus. With PDA, extra blood flows to the lungs. The blood vessels and the lungs have to work much harder to handle the extra blood.

(See how patent ductus arteriosus affects blood flow into the lungs in this animated video.)

Doctors don't know exactly why patent ductus arteriosus occurs, but it is more common in babies born prematurely and occurs twice as often in girls as in boys. Patent ductus arteriosus can also occur along with other heart defects.

For more information about patent ductus arteriosus or to make an appointment with a pediatric cardiologist, please call 314.454.5437 or 800.678.5437 or email us.

Symptoms of Patent Ductus Arteriosus

The size of the opening between the aorta and the pulmonary artery will affect the symptoms associated with the condition. A small opening may cause little to no symptoms, while a larger opening may display some or all of the symptoms below:

  • Cyanosis (bluish skin from not getting enough oxygen)
  • Fatigue
  • Fast or hard breathing
  • Trouble feeding, or tiredness while feeding
  • Infections
  • Poor weight gain
  • In older children, trouble doing activities

The symptoms of patent ductus arteriosus can resemble the symptoms of other health conditions, so make sure your child sees a healthcare provider if they are exhibiting any of the above symptoms.

To speak with a healthcare professional at St. Louis Children's Hospital, please call 314.454.5437 or 800.678.5437 or email us.

Diagnosis of Patent Ductus Arteriosus

The first step in diagnosing patent ductus arteriosus is a physical exam and to discuss your baby's symptoms and health history with a healthcare provider. During the exam, your child's healthcare provider will look for the symptoms associated with patent ductus arteriosus, as well as the presence of a heart murmur. If the healthcare provider suspects a diagnosis of patent ductus arteriosus, you may be referred to a pediatric cardiologist, a doctor with special training to diagnose and treat heart problems in children.

The pediatric heart specialist will also conduct a physical examination of your baby and listen to his or her heart and lungs. The details about the heart murmur will help the cardiologist make the final diagnosis.

As part of the examination, your baby may need additional cardiac testing and imaging, such as:

  • Chest X-ray. A chest X-ray may show an enlarged heart and lung changes in a baby with patent ductus arteriosus.
  • 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 pattern of blood flow through the patent ductus arteriosus, how large the opening is, and how much blood is passing through it. An echo is the most common way that a patent ductus arteriosus is diagnosed.
  • Cardiac catheterization. For this test, your baby will be given medicine to relax (sedation) and the healthcare provider will put a thin, flexible tube (catheter) into a blood vessel in the groin. The catheter is guided through the blood vessel to the heart. The heart is then checked, including measuring blood pressure and oxygen in the four chambers of the heart. The pulmonary artery and aorta are also checked. Contrast dye may be injected so the provider can more clearly see the structures inside the heart.

For more information about how patent ductus arteriosus is diagnosed or to make an appointment with a pediatric cardiologist, please call 314.454.5437 or 800.678.5437 or email us.

Patent Ductus Arteriosus Treatment

Treatment will depend on how severe the patent ductus arteriosus condition is and on your child’s symptoms, age and general health. If left untreated, patent ductus arteriosus may lead to long-term lung damage as well as damage to the blood vessels in the lungs

A small patent ductus arteriosus with no symptoms may close on its own as your child grows. A patent ductus arteriosus that causes symptoms will need to be treated with medicine or heart surgery. The cardiologist will check periodically to see whether the patent ductus arteriosus is closing on its own, and, if the PDA does not close, it will be fixed to prevent lung problems.

Treatment of patent ductus arteriosus may include the following:


Your baby may need medicines help the heart work better.

  • In premature infants, the medicine indomethacin may help close the patent ductus arteriosus. Indomethacin is given intravenously and it helps stimulate the muscles inside the patent ductus arteriosus to tighten and close the connection. 
  • Some babies may need diuretic medicines to help the heart and lungs work better. Diuretics help the kidneys remove extra fluid from the body, which may be needed when the heart is not working well


Most infants with patent ductus arteriosus eat and grow normally; however, some premature infants or infants with large PDAs may become 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 properly.
  • Supplemental tube feedings. Supplemental feedings are given through a small, flexible tube. The tube passes through the nose, down the 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. Infants who are too tired to bottle-feed may get all of their formula or breastmilk through the feeding tube.

Cardiac catheterization

Closure of the patent ductus arteriosus can be done using cardiac catheterization. Metal mesh coils or blocking devices can be put in the PDA using a catheter. This patent ductus arteriosus treatment is usually reserved for beyond infancy and for those whose PDA is not very large. 

Heart surgery

Surgical closure of a patent ductus arteriosus involves closing the PDA with stitches or clips. This prevents the extra blood from entering the lungs. Premature babies require this surgery and it is usually advised for babies younger than six months of age who have large defects and who have symptoms such as poor weight gain and fast breathing. For babies who do not have symptoms, surgery may be delayed until after 6 to 12 months of age. Your child's cardiologist will recommend if and when the surgery should be done.

If you have any questions about the patent ductus arteriosus treatment options, please call 314.454.5437 or 800.678.5437 or email us.

Ongoing Care of Patent Ductus Arteriosus

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

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

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

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 patent ductus arteriosus lets them live normal, healthy lives. Activity levels, appetite, and growth should return to normal. Your child's cardiologist may recommend 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.

It is important to talk with your child's cardiologist about your child’s outlook.

For more information regarding patent ductus arteriosus in St. Louis or to make an appointment, please call 314.454.5437 or 800.678.5437 or email us.