Patent Ductus Arteriosus

A patent ductus arteriosus (PDA) is a common congenital heart condition in newborns. The ductus arteriosus is a normal blood vessel in unborn babies that connects the two major blood vessels from the heart and allows blood to bypass the lungs. After birth, the ductus arteriosus is expected to close on its own; when it stays open, it is called a PDA. In some infants — particularly those born prematurely — a PDA allows too much blood to flow to the lungs and not enough to the rest of the body. A small PDA may not cause symptoms or require treatment. However, a large PDA can cause blood to flow in the wrong direction, forcing the heart to work harder. Over time, this can weaken the heart and lead to heart failure and other serious complications.

PDAs are more common in premature infants because their bodies aren’t mature enough to close the ductus arteriosus on their own. Common lung diseases associated with preterm birth, such as respiratory distress syndrome and low oxygen saturations, also interfere with normal closure. The more premature and smaller the infant, the higher the risk of a PDA. Many PDAs close on their own in time, but some require careful monitoring and treatment by specialized neonatal and pediatric cardiology teams. Treatment for preterm infants can include medicine, surgery to close the opening, or a minimally invasive catheter procedure.

At Boston Children’s Hospital, our Premature PDA Closure Program is one of the largest programs in the country dedicated to supporting infants who may need PDA closure. Our team provides expert consultation, treatment, and follow-up care for these complex and fragile cases.

Common signs and symptoms of a PDA may include:

• A heart murmur
• Trouble breathing
• Pauses in breathing (apnea)
• An increasing need for oxygen and respiratory support
• Changes in blood pressures
• Poor weight gain

The presence of a PDA is usually noted in the first few days of life. How a PDA affects an infant depends on its size and the amount of extra blood flowing through it. If untreated, a PDA can cause increased pressure in the lungs (pulmonary hypertension) and long-term heart and lung damage.

The exact cause of a PDA isn’t fully understood. Before birth, the ductus arteriosus allows oxygen-rich blood from the placenta to reach the fetus while bypassing the lungs, which aren’t used for breathing while the fetus is in the womb. The ductus arteriosus usually closes within two to three days after birth, but in some infants it remains open.

A PDA is diagnosed using a combination of tests, including:

• Physical exam
• Chest X-ray and blood pressure monitoring
• Echocardiogram (heart ultrasound)

A PDA is considered a hemodynamically significant PDA (hsPDA) when the extra blood flow stresses the lungs and heart or reduces blood flow to other organs. Because there is no single definition, doctors evaluate each infant individually to guide treatment decisions. To determine a hsPDA, doctors will evaluate:

• The size of the PDA and the direction of blood flow
• How the PDA affects heart and lung function
• Signs that blood flow to organs such as the kidneys, brain, or intestines may be reduced

Most PDAs do not require treatment. Treatment is considered when:

• The PDA affects breathing or heart function
• There is poor blood flow to vital organs
• Symptoms worsen despite supportive care

Your baby’s care team will choose the treatment option that’s best for baby based on their size, age, and overall condition.

Treatment of a PDA depends on an infant’s size, age, symptoms, and overall health. Some PDAs are small and close on their own, while others need treatment to prevent strain on the heart or lungs. Your care team will recommend the safest and most effective option for your baby.

Treatment options may include:

• Monitoring and supportive care: If the PDA is small and is not causing symptoms, doctors may monitor it closely over time. Some PDAs close naturally as a baby grows, which can be a safe option especially if there are no signs of breathing problems, poor growth, or heart strain.
• Medication: Certain medications may help close the PDA in premature infants. Medications such as indomethacin, ibuprofen, and acetaminophen work by stimulating the muscles inside the PDA to tighten and close the connection.
• Catheter-based (minimally invasive) closure: In many cases, a PDA can be closed using a cardiac catheterization procedure. During this procedure, a thin tube is guided through a blood vessel to the heart, where a small device is placed to seal the PDA. This approach often avoids surgery and allows for faster recovery. Newer devices now make this option possible for very small and premature infants.
• Surgical repair: We may recommend surgery if medication or catheter-based closure is not appropriate. During surgery, the PDA is closed through a small incision in the chest using a clip or suture. This procedure is done under general anesthesia.

Your child’s neonatology and cardiology teams will work together to carefully determine when treatment is needed and which option is best, based on how the PDA is affecting their heart, lungs, and overall growth.

Most children with a PDA recover well from closure. Their activity levels, appetite, and growth should return to normal. Early recognition, careful assessment of hemodynamic significance, and individualized treatment are key to optimizing long-term heart and lung health.

The first successful PDA closure ever was done here at Boston Children’s Hospital in 1938 by renown surgeon Dr. Robert Gross. Today, therapies have advanced tremendously and we now provide multidisciplinary care for infants and children with a patent ductus arteriosus (PDA) to determine the best treatment option. Our teams specialize in catheter-based treatments that often avoid open-heart surgery and allow for faster recovery. Older infants and children with a PDA are cared for through the Benderson Family Heart Center, while our Premature PDA Closure Program brings together cardiologists, newborn specialists, surgeons, and respiratory therapists to care for extremely small and premature babies, including those who can benefit from minimally invasive PDA closure.

Boston Children’s Hospital is home to one of the nation’s most advanced pediatric cardiac research programs and is a world leader in translational research — bringing advances from the lab to patients as quickly as possible. Our clinical and research teams use real-time heart and lung data to guide precision care for critically ill newborns, especially premature infants. Our Premature PDA Closure Program is one of the few specialized programs of its kind — delivering cutting-edge care and simultaneously studying the effects of a PDA and its treatment, including minimally invasive device closure for extremely small newborns. Our SmallWonder Neonatal Cardiovascular Research Group collaborates across Cardiology, Newborn Medicine, Surgery, and Respiratory Therapy, to develop and refine approaches to diagnose and treat the PDA and other heart and lung conditions.