Patent Ductus Arteriosus Treatment in Delhi, India

Patent Ductus Arteriosus (PDA) is a congenital heart defect that primarily affects premature babies, especially those born before 30 weeks of gestation. It occurs when a vital fetal blood vessel, the ductus arteriosus, fails to close after birth. Before birth, this vessel helps blood bypass the baby's lungs, but it should close naturally soon after birth. If left untreated, PDA can put excessive strain on the heart and lungs, increasing the risk of heart failure, pulmonary hypertension, and other complications. Early detection and appropriate treatment are essential to prevent long-term health issues.

Depending on the size of the opening and the amount of blood it allows to flow between the aorta and pulmonary artery, PDA can be categorised into different types, each with distinct characteristics and potential health implications. 

Silent PDA

This type of PDA does not cause noticeable hemodynamic changes (does not significantly affect blood flow or heart function) and resolves on its own. It is often detected incidentally during an echocardiogram performed to diagnose other problems. Though silent PDA is asymptomatic, it may still lead to infective endocarditis in some cases.

Small PDA 

In this congenital heart condition, the ductus arteriosus remains open but is narrow, allowing only a minimal amount of blood to pass through. Because the opening is small, the amount of extra blood flowing into the lungs is minimal, and it does not usually strain the heart or lungs significantly.

Moderate PDA 

This PDA subtype allows more blood than silent and small PDA to flow between the aorta and pulmonary artery, leading to left-to-right shunting (meaning oxygenated blood is recirculated back to the lungs instead of going to the body). As pulmonary blood flow increases, the heart and lungs are forced to overwork. 

Large PDA

The ductus arteriosus opens wider in large PDA as compared to silent, small, and moderate PDA. It causes significant left-to-right shunting, leading to left ventricular volume overload. Left unaddressed, large PDA can lead to pulmonary hypertension, which can cause irreversible lung damage over time. 

Eisenmenger PDA

In Eisenmenger PDA, the opening is not necessarily "too wide" in all cases, but rather it becomes bidirectional and right-to-left shunting occurs due to pulmonary hypertension and increased pulmonary vascular resistance.

Though the exact cause of Patent Ductus Arteriosus (PDA) is not always known, there are certain conditions and circumstances that are commonly associated with its development.

Premature Birth 

The ductus arteriosus in preterm babies has less muscle tissue, making it less responsive to the signals that trigger closure (as a result it may not close). High prostaglandins levels (often associated with preterm birth) and low oxygen levels can also prevent the ductus arteriosus from closing. No wonder patent ductus arteriosus is more common in premature babies than babies who are born full term. 

Genetic Factors 

Here are some single gene mutations that can cause PDA: 

• Mutations in the TFAP2B: Are associated with Char syndrome, which can cause PDA
• Mutations in the NOTCH1 gene: Can affect vascular development and have been linked to PDA
• Mutations in the PITX2 gene: Because the PITX2 gene plays a role in heart development, mutations in this gene can cause PDA 

Health Conditions That Affect Maternal Health 

Here are a couple of maternal health conditions that can cause PDA:

• Rubella (German measles) during pregnancy: The rubella virus can damage the fetal heart and blood vessels
• Gestational diabetes: Uncontrolled diabetes can affect fetal circulation and delay the closure of the ductus arteriosus

Hypoxia (Low Oxygen Levels in the Womb)

Intrauterine growth restriction (IUGR) and other conditions that lead to low oxygen levels in the fetus, can delay the normal closure of the ductus arteriosus. Chronic fetal hypoxia due to placental insufficiency may cause PDA.

Certain Medications 

The following medications can cause PDA if taken during pregnancy:

• Ibuprofen, indomethacin, and aspirin - Reduce prostaglandin (hormone-like lipids that keep the ductus arteriosus open in the fetus) levels
• Fluoxetine, sertraline, and paroxetine - Can lead to persistent pulmonary hypertension
• Valproic acid and phenytoin- Disrupt fetal heart development and can lead to congenital heart defects

The potential risk factors for patent ductus arteriosus include the following:

Low Birth Weight 

The patent ductus arteriosus closes due to muscle contraction in its walls. In babies born weighing less than 2,500 grams, the smooth muscle in the DA is underdeveloped, making it less responsive to oxygen and closure signals. 

Gender 

PDA is twice as common in female infants than in male infants as estrogen and other female sex hormones relax blood vessels delaying the closure of the patent ductus arteriosus. Some genes that affect vascular development are linked to the X chromosome. Since females have two X chromosomes, female infants are more likely to develop PDA 

Oxygen and Respiratory Issues

Conditions such as neonatal respiratory distress syndrome (RDS), persistent pulmonary hypertension of the newborn (PPHN), and meconium aspiration syndrome can affect a baby’s blood oxygen levels (hypoxia), increasing their risk of PDA. 

Multiple Birth

Multiple pregnancies often result in preterm birth, as the uterus is stretched more and labour tends to start earlier. The earlier a baby is born, higher the chances that the ductus arteriosus remains open instead of closing after birth.

Other Congenital Heart Defects

Cyanotic congenital heart defects such as transposition of the great arteries (TGA), tetralogy of Fallot (TOF), and hypoplastic left heart syndrome (HLHS) lead to low blood oxygen levels. Since oxygen helps trigger the closure of the ductus arteriosus, persistent hypoxia can keep it open.

The symptoms of PDA can vary depending on the size of the opening and the severity of the condition. While some infants with PDA may have no noticeable symptoms, others may experience difficulty breathing, poor weight gain, or heart murmurs.

Breathing Problems 

When the ductus arteriosus remains open, it allows oxygenated blood from the aorta to flow back into the pulmonary artery. This increases blood volume in the lungs, leading to pulmonary congestion, which causes breathing problems. In premature babies, PDA can lead to chronic lung disease and bronchopulmonary dysplasia (BPD)-often associated with shortness of breath and other breathing problems. 

Heart Murmur

In PDA, oxygenated blood does not circulate through the body and is pushed from the high-pressure aorta into the low-pressure pulmonary artery instead. This abnormal movement of blood creates turbulence, leading to a continuous "machine-like" murmur. 

Slow Weight Gain 

Patent ductus arteriosus causes more blood to flow to the lungs. As a result, the heart is forced to work harder and uses more energy than usual. This leads to unintentional weight loss, rather than weight gain. Excess blood flow to the lungs can also cause pulmonary edema, making it harder for the baby to breathe. Increased respiratory effort further burns calories, leading to slow weight gain in infants. 

Fatigue and Lethargy 

When more blood flows into the lungs instead of reaching the body, less oxygen is delivered to muscles and tissues, leading to lethargy. Left unaddressed, PDA can weaken heart muscles. As their heart struggles to pump blood effectively, the baby can experience fatigue. 

Frequent Respiratory Infections 

PDA can cause pulmonary edema-a condition characterised by a buildup of fluid (in this case blood) in the lungs. Too much fluid in the lungs creates the right conditions for bacteria and viruses that cause respiratory infections to grow.

A heart murmur typically heard through a stethoscope during a routine checkup can indicate PDA. To confirm a diagnosis, imaging techniques such as echocardiography, chest X-rays, and electrocardiograms (ECG) are commonly used. 

Clinical Evaluation 

If a doctor suspects that a baby has PDA, they evaluate the infant’s symptoms. The physician also conducts a physical examination that may involve checking the baby’s pulse (to check for a bounding pulse), measuring their heart rate, and listening to the baby’s heart using a stethoscope.

Imaging Tests 

Some common imaging tests used to diagnose PDA include:

• Echocardiography- Helps identify a left-to-right shunt and measure pulmonary artery pressure 
• Chest X-ray- Helps identifypulmonary congestion and diagnose an enlarged heart due to volume overload
• Electrocardiography- Doctors use an ECG to diagnose left and right ventricular hypertrophy

Cardiac Catheterisation

If non-invasive diagnostic techniques generate inconclusive results, cardiac catheterisation, an invasive imaging technique is used. It involves inserting a catheter into the heart to measure pressure in the aorta, pulmonary artery, and left atrium (abnormal pressure patterns can indicate PDA). 

MRI

An MRI is usually ordered when echocardiography results are inconclusive. The imaging test generates detailed images of the heart and blood vessels, helping doctors quantify left-to-right shunts and calculate the shunt fraction (Qp/Qs ratio).

Pulse Oximetry

The noninvasive imaging technique helps doctors calculate pre-ductal and post-ductal oxygen saturation levels. A significant difference (≥3-5%) between pre-ductal and post-ductal oxygen saturation levels could mean that deoxygenated blood is shunting from the pulmonary artery to the aorta.

Depending on the patient’s condition and their overall health, a doctor may use one or more of the following PDA treatment options:

Medication 

Often administered intravenously, NSAIDs such as indomethacin and ibuprofen regulate prostaglandins production, helping keep the ductus arteriosus open. If NSAIDs are not effective or contraindicated, acetaminophen (reduces prostaglandins production and has fewer side effects than NSAIDs) may be used. 

Catheter-Based Closure

The minimally invasive procedure involves inserting a catheter into a blood vessel (usually in the groin) and guiding it to the heart. Next, a PDA occluder device or coil is placed in the ductus arteriosus to seal it.Over time, tissue grows over the device, permanently closing the opening.

Surgical Ligation

When catheter-based closure is not possible (the baby cannot tolerate a catheter or heart failure occurs), doctors may perform a corrective surgical procedure, known as surgical ligation. The procedure involves making a tiny incision in the left side of the chest (thoracotomy) and ligating the ductus using surgical sutures or clips.

While Patent Ductus Arteriosus (PDA) cannot always be completely prevented, especially in premature infants, certain prenatal and neonatal care practices can significantly reduce the risk and promote better heart health in newborns.

Prevent Preterm Birth

Since PDA is more common in premature babies, preventing preterm labour is the most effective way to reduce its risk. Here are some ways to prevent preterm birth:

Realise the Importance of Prenatal Care

Regular prenatal check-ups help monitor the baby’s development and identify potential complications early, paving the way for timely intervention (if a congenital defect is diagnosed). 

Maintain a Healthy, Balanced Diet

Pregnant women should add foods high in folic acid, calcium, omega-3 fatty acids, and other nutrients that support healthy fetal development to their diet. They must also take prenatal vitamins as prescribed by their doctor to reduce the risk of congenital heart defects.

Break Bad Habits 

Women should avoid using drugs, alcohol, and tobacco during pregnancy as they can lead to preterm birth and congenital defects. Mothers-to-be must also reduce their caffeine intake and avoid exposure to secondhand smoke.

Manage Chronic Conditions

Diabetes, high blood pressure, and infections during pregnancy can increase the risk of PDA and other complications. Pregnant women living with these chronic conditions should follow their doctor’s instructions and maintain a healthy lifestyle to manage their symptoms. 

Prevent and Treat Maternal Infections

Rubella (German measles) and some other infections during pregnancy can cause PDA. Women should get vaccinated before pregnancy and avoid contact with infected individuals to prevent infections that can affect fetal development. 

Postnatal Care and Management

In premature babies, oxygen therapy can help maintain oxygen levels, reducing the risk of PDA. In some preterm babies, nonsteroidal anti-inflammatory drugs (NSAIDs) such as indomethacin and ibuprofen can help close the ductus arteriosus. Overhydration can increase blood flow through the ductus arteriosus, preventing it from closing. Neonatologists carefully regulate fluid intake in preterm infants and take steps to prevent water intoxication. 

Genetic Counselling 

If a congenital heart defect runs in the family, a genetic counsellor can help assess the fetus’s risk of developing PDA and suggest preventive measures.

How is PDA treated in preterm infants compared to full-term babies?

Treatment for PDA in preterm infants often begins with medications like ibuprofen or indomethacin to encourage closure. If these fail, a minimally invasive catheter-based procedure or surgery may be required. In full-term babies, small PDAs may close naturally, while larger ones may need intervention through catheter-based closure or surgical ligation.

What medications are used to close a PDA, and how do they work?

Doctors commonly prescribe nonsteroidal anti-inflammatory drugs (NSAIDs) such as indomethacin or ibuprofen to help close a PDA. These medications work by reducing prostaglandin levels, which play a role in keeping the ductus arteriosus open. Acetaminophen is sometimes used as an alternative when NSAIDs are not suitable.

When is catheter-based closure preferred over surgery for PDA?

Catheter-based closure is preferred when the PDA is moderate to large in size and the infant is stable enough for a minimally invasive approach. It is the first-line treatment for older infants, children, and adults with PDA, as it avoids the risks associated with open-heart surgery.

What are the benefits of minimally invasive PDA closure?

Minimally invasive PDA closure, performed via cardiac catheterisation, offers several advantages, including shorter recovery time, reduced risk of infection, minimal scarring, and less postoperative discomfort compared to open surgery.

Can PDA reopen after successful treatment?

While rare, PDA can reopen, particularly in cases where initial closure was achieved through medication. In such instances, catheter-based intervention or surgery may be required to permanently close the ductus arteriosus.

What complications can arise if PDA is left untreated?

An untreated PDA can lead to heart failure, pulmonary hypertension, frequent respiratory infections, and an increased risk of infective endocarditis. Over time, excessive blood flow to the lungs can cause irreversible damage to the pulmonary vessels.

Is PDA treatment different for adults compared to infants?

Yes, PDA treatment differs by age. In infants, especially preterm babies, treatment often starts with medication to encourage the duct to close. If that fails, a catheter-based procedure or surgery may be needed. In adults, catheter-based closure is preferred, as surgical intervention carries higher risks. Long-standing untreated PDA in adults may also require additional treatment for complications like pulmonary hypertension or heart failure.

How long does recovery take after PDA closure?

Recovery time depends on the type of procedure. For catheter-based closure, most patients recover within a few days and can resume normal activities within a week. Surgical PDA closure may require a hospital stay of a few days, with full recovery taking several weeks.

Are there any long-term lifestyle changes after PDA treatment?

Most children and adults can lead normal, active lives after successful PDA closure. However, in some cases, doctors may recommend routine cardiac follow-ups to monitor heart function, especially if PDA causes complications before treatment.

Can PDA be detected and treated before birth?

While PDA itself cannot be treated before birth, it can be detected during prenatal ultrasounds if there are concerns about congenital heart defects. In certain cases, medications may be given to the mother to manage conditions that increase the risk of PDA.

Reviewed by Dr Muthu Jothi, Director – Paediatric Cardiac Surgery, Paediatric (Ped) Cardiac Surgery, Paediatric (Ped) Cardiology, on 12 June 2025.