Patent ductus arteriosus

Synonyms

4

Overview

Patent ductus arteriosus (PDA) is a persistent opening between two major blood vessels leading from the heart. The opening, called the ductus arteriosus, is a normal part of a baby's circulatory system before birth that usually closes shortly after birth. If it remains open, however, it's called a patent ductus arteriosus. A small patent ductus arteriosus often doesn't cause problems and might never need treatment. However, a large patent ductus arteriosus left untreated can allow poorly oxygenated blood to flow in the wrong direction, weakening the heart muscle and causing heart failure and other complications. Treatment options include monitoring, medications and closure by cardiac catheterization or surgery.

Symptoms

Patent ductus arteriosus symptoms (PDA) vary with the size of the defect and whether the baby is full-term or premature. A small PDA might cause no signs or symptoms and go undetected for some time — even until adulthood. A large PDA can cause signs of heart failure soon after birth.

Your baby's doctor might first suspect a heart defect during a regular checkup after hearing a heart murmur while listening to your baby's heart through a stethoscope.

A large PDA found during infancy or childhood might cause:

  • Poor eating, which leads to poor growth
  • Sweating with crying or eating
  • Persistent fast breathing or breathlessness
  • Easy tiring
  • Rapid heart rate

Causes

Congenital heart defects arise from problems early in the heart's development — but there's often no clear cause. Genetics and environmental factors might play a role. Before birth, a vascular connection (ductus arteriosus) between two major blood vessels leading from the heart — the aorta and pulmonary artery — is necessary for the baby's blood circulation. The ductus arteriosus diverts blood from the baby's lungs while they develop and the baby receives oxygen from the mother's circulation.

After birth, the ductus arteriosus normally closes within two or three days. In premature infants, the connection often takes longer to close. If the connection remains open, it's referred to as a patent ductus arteriosus. The abnormal opening causes too much blood to circulate to the baby's lungs and heart. Untreated, the blood pressure in the baby's lungs might increase (pulmonary hypertension) and the baby's heart might enlarge and weaken.

Risk factors for having a patent ductus arteriosus include:

  • Premature birth. Patent ductus arteriosus (PDA) occurs more commonly in babies who are born too early than in babies who are born full term.
  • Family history and other genetic conditions. A family history of heart defects and other genetic conditions, such as Down syndrome, increase the risk of having a PDA.
  • Rubella infection during pregnancy. If you contract German measles (rubella) during pregnancy, your baby's risk of heart defects increases. The rubella virus crosses the placenta and spreads through the baby's circulatory system, damaging blood vessels and organs, including the heart.
  • Being born at a high altitude. Babies born above 10,000 feet (3,048 meters) have a greater risk of a PDA than babies born at lower altitudes.

Prevention

There's no sure way to prevent having a baby with a patent ductus arteriosus. However, it's important to do everything possible to have a healthy pregnancy. Here are some of the basics:

  • Seek early prenatal care, even before you're pregnant.Quitting smoking, reducing stress, stopping birth control — these are all things to talk to your doctor about before you get pregnant. Also discuss medications you're taking.
  • Eat a healthy diet. Include a vitamin supplement that contains folic acid.
  • Exercise regularly. Work with your doctor to develop an exercise plan that's right for you.
  • Avoid risks. These include harmful substances such as alcohol, cigarettes and illegal drugs. Also avoid hot tubs and saunas.
  • Avoid infections. Update your vaccinations before becoming pregnant. Certain types of infections can be harmful to a developing baby.
  • Keep diabetes under control. If you have diabetes, work with your doctor to manage the condition before and during pregnancy.

If you have a family history of heart defects or other genetic disorders, consider talking with a genetic counselor before becoming pregnant.

Diagnosis

Babies with PDA often have a characteristic heart murmur that can be heard with a stethoscope. However, in premature infants, a heart murmur may not be heard. Doctor's may suspect the condition if the infant has breathing or feeding problems soon after birth. Changes may be seen on chest x-rays. The diagnosis is confirmed with an echocardiogram. Sometimes, a small PDA may not be diagnosed until later in childhood.

If the doctor suspects a heart defect, he or she might request one or more of the following tests:

  • Echocardiogram. Sound waves produce images of the heart that can help the doctor identify a PDA, see if the heart chambers are enlarged, and judge how well the heart is pumping. This test also helps the doctor evaluate the heart valves and detect other potential heart defects.
  • Chest X-ray. An X-ray image helps the doctor see the condition of your baby's heart and lungs. An X-ray might reveal conditions other than a heart defect, as well.
  • Electrocardiogram (ECG). This test records the electrical activity of the heart, which can help the doctor diagnose heart defects or rhythm problems.
  • Cardiac catheterization. This test isn't usually necessary for diagnosing a PDA alone, but it might be done to examine other congenital heart defects found during an echocardiogram or if a catheter procedure is being considered to treat a PDA. A thin, flexible tube (catheter) is inserted into a blood vessel at your child's groin or arm and guided through it into the heart. Through catheterization, the doctor can do procedures to close the patent ductus arteriosus.

Prognosis

If the patent ductus is not closed, the infant has a risk of developing heart failure, pulmonary artery hypertension, or infective endocarditis, an infection of the inner lining of the heart.

Treatment

The goal of treatment, if the rest of circulation is normal or close to normal, is to close the PDA. In the presence of certain other heart problems, such as hypoplastic left heart syndrome, the PDA may actually be lifesaving. Sometimes, a PDA may close on its own. Premature babies have a high rate of closure within the first 2 years of life. In full-term infants, a PDA rarely closes on its own after the first few weeks. 

Treatments for patent ductus arteriosus depend on the age of the person being treated. Options might include:

  • Watchful waiting. In a premature baby, a PDA often closes on its own. The doctor will monitor your baby's heart to make sure the open blood vessel is closing properly. For full-term babies, children and adults who have small PDAs that aren't causing other health problems, monitoring might be all that's needed.
  • Medications. In a premature baby, nonsteroidal anti-inflammatory drugs (NSAIDs) — such as ibuprofen (Advil, Infant's Motrin), ibuprofen lysine (Neoprofen) or indomethacin (Indocin) — might be used to help close a PDA. NSAIDs block the hormonelike chemicals in the body that keep the PDA open. NSAIDs won't close a PDA in full-term babies, children or adults.
  • Open-heart surgery. If medications aren't effective and your child's condition is severe or causing complications, open-heart surgery might be recommended. A surgeon makes a small cut between your child's ribs to reach your child's heart and repair the open duct using stitches or clips. After the surgery, your child will remain in the hospital for several days for observation. It usually takes a few weeks for a child to fully recover from open-heart surgery. Open-heart surgery might also be recommended for adults who have a PDA that's causing health problems. Possible risks include hoarseness, bleeding, infection and a paralyzed diaphragm.
  • Catheter procedures. Premature babies are too small for catheter procedures. However, if your baby doesn't have PDA-related health problems, the doctor might recommend waiting until the baby is older to do a catheter procedure to correct the PDA. Catheter procedures can also be used to treat full-term babies, children and adults. In a catheter procedure, a thin tube (catheter) is inserted into a blood vessel in the groin and threaded up to the heart. Through the catheter, a plug or coil is inserted to close the ductus arteriosus. If the procedure is done on an outpatient basis, your child probably won't stay overnight in the hospital. Complications from catheter procedures include bleeding, infection, or movement of the plug or coil from where it was placed in the heart.

Preventive antibiotics:
In the past, people who've had a PDA were advised to take antibiotics before dental work and certain surgical procedures to prevent a heart infection (infective endocarditis). Today, preventive antibiotics are no longer recommended for most people with a patent ductus arteriosus.
Your child may need to take preventive antibiotics the first six months after a catheter repair procedure or if there's still damage after the repair. Talk to your doctor about whether your child needs to take antibiotics before any procedures.

Resources

Refer to Research Publications.