Patent ductus arteriosus (PDA) is a persistent, abnormal opening between two major blood vessels leading from the heart. Fortunately, this heart defect present at birth (congenital) often closes on its own or is readily treatable.

A small patent ductus arteriosus often doesn't cause symptoms. A doctor may discover it during a routine exam. An infant with a larger patent ductus arteriosus often has trouble gaining weight and exhibits other symptoms. An older child with a patent ductus arteriosus may not be as active as normal, may tire more easily and may have frequent lung infections.

Treatment options for repairing a patent ductus arteriosus include medications and surgery.

Signs and symptoms of a patent ductus arteriosus vary with the size of the defect and the gestational age of the infant at birth. A small patent ductus may cause no signs or symptoms, and may go undetected for some time. A larger one can cause signs of heart failure soon after birth. A premature infant may have other problems associated with prematurity, and related testing may uncover a heart defect.

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

A large patent ductus arteriosus may cause:

• Poor eating, poor growth
• Sweating with crying or play
• Persistent fast breathing or breathlessness
• Easy tiring
• Rapid heart rate
• Frequent lung infections

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Patent ductus arteriosus

Patent ductus arteriosus is common in premature babies, but rare in infants born at full term.

As a baby develops in the womb, a vascular connection (ductus arteriosus) between two major blood vessels leading from the heart — the aorta and pulmonary artery — is a normal and necessary part of fetal circulation. But, this duct is supposed to close within two or three days after birth once the newborn's heart adapts to life outside the womb. In premature infants, the duct often closes on its own within a few weeks of birth. But if the duct remains open, it's referred to as a patent ductus arteriosus.

The abnormal opening causes too much blood to circulate to the lungs and heart. If not treated, the blood pressure in the lungs may increase (pulmonary hypertension) and the heart may weaken.

Congenital heart defects arise from errors early in the heart's development — but there's often no clear cause. Genetics and perhaps environmental factors may play a role.

Congenital heart defects appear to run in families and sometimes occur with other genetic problems, such as Down syndrome. If you have a child with a congenital heart defect, a genetic counselor can predict the approximate odds that any future children could have one.

Patent ductus arteriosus is more common in premature babies. Also, babies with other types of congenital heart defects often have a patent ductus arteriosus.

Experiencing any of the following conditions during pregnancy can increase your risk of having a baby with a heart defect.

• Rubella infection. Becoming infected with rubella (German measles) while pregnant can increase the risk of fetal heart defects. The rubella virus crosses the placenta and spreads through the fetus's circulatory system damaging blood vessels and organs, including the heart.
• Poorly controlled diabetes. Uncontrolled diabetes in the mother in turn affects the fetus's blood sugar causing various damaging effects to the developing fetus.
• Drug or alcohol use or exposure to certain substances. Use of certain medications, alcohol or drugs, or exposure to chemicals or radiation during pregnancy can harm the developing fetus.

Call your doctor if your infant or child:

• Tires easily when eating or playing
• Is not gaining weight
• Becomes breathless when eating or crying
• Always breathes rapidly or is short of breath
• Turns dusky or blue when crying or eating

Your baby's doctor may detect a heart defect when listening to his or her heart. Patent ductus arteriosus can cause a heart murmur that your doctor can hear through a stethoscope. If your doctor hears a heart murmur or finds other signs or symptoms of a heart defect, he or she may request one or more of these tests:

• Echocardiogram. An echocardiogram uses sound waves to produce a video image of the heart. This image can help doctors see the heart chambers and evaluate how well the heart is pumping. This test also checks the heart valves and looks for any other heart defects.
• Chest X-ray. An X-ray image helps the doctor see the condition of your baby's heart and lungs and the amount of blood in the lungs. An X-ray may identify conditions other than a heart defect that may explain your baby's symptoms.
• Electrocardiogram (ECG). This test records the electrical activity of your baby's heart. This test helps diagnose heart defects or rhythm problems.
• Cardiac catheterization. In this test, a thin, flexible tube (catheter) is inserted into a blood vessel at your baby's groin or arm and guided through it into the heart. Through catheterization, doctors can do further testing to evaluate congenital heart defects found during echocardiography. In certain defects, treatment procedures can be done during cardiac catheterization to improve the heart's function.

Occasionally, a small patent ductus arteriosus may not be detected until adulthood.

A small patent ductus arteriosus may not cause symptoms. Larger defects that are untreated can cause high blood pressure in the lungs (pulmonary hypertension), frequent lung infections, irregular heartbeat (arrhythmia) or heart failure, a chronic condition in which the heart can't pump effectively.

People with structural heart problems, such as a patent ductus arteriosus, are at a higher risk of infectious endocarditis than is the general population. Infectious endocarditis is an inflammation of the inner lining of the heart caused by a bacterial infection.

Rarely, pulmonary hypertension can cause permanent lung damage, and pulmonary hypertension becomes irreversible (Eisenmenger's syndrome).

Patent ductus arteriosus and pregnancy
Pregnancy is often a concern for women born with a heart defect. Most women with patent ductus arteriosus can tolerate pregnancy without any problems. However, having a larger defect or having complications such as heart failure, arrhythmias or pulmonary hypertension can increase your risk of complications during pregnancy. Doctors strongly advise women with Eisenmenger's syndrome not to become pregnant because it can endanger the woman's life.

The risk of congenital heart disease in the general population is less than 1 percent. For children of parents with congenital heart disease, whether father or mother, this risk increases to between 2 percent and 20 percent, according to the American Heart Association. Experts recommend that anyone with a congenital heart defect, repaired or not, who is considering starting a family, carefully discuss it beforehand with his or her doctor.

In some cases, preconception consultations with doctors who specialize in cardiology, genetics and high-risk obstetric care are needed. Some heart medications can cause serious problems for a fetus and may need to be stopped or adjusted before you become pregnant.

In a premature infant, the patent ductus arteriosus often closes on its own in the weeks after birth. In a full-term infant, a patent ductus arteriosus usually will close within the first few days of life. If the defect doesn't close and is causing health problems, medications or surgery may be used to close it.

Medications
Doctors use nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or indomethacin, to help close a patent ductus arteriosus in premature infants. NSAIDs block the hormone-like chemicals in the body that keep the PDA open.

Surgery
Surgery to repair a patent ductus arteriosus involves patching or sewing shut the abnormal opening. This can be done through an incision in the side of the chest or by catheterization. In cardiac catheterization, 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 may be deployed to close the ductus arteriosus. In surgery, the ductus is closed with a metal clip.

Preventive antibiotics
In the past, it was recommended that people with an unrepaired patent ductus arteriosus take antibiotics before dental work and certain types of surgical procedures to prevent infective endocarditis.

But new guidelines issued by the American Heart Association in 2007 have substantially revised this recommendation. After weighing the risks and benefits of preventive antibiotics, the reviewing committee found that the risks outweighed the benefits for most people, except a small group at high risk of serious complications of infectious endocarditis.

The reviewers found that random germs caused infectious endocarditis more frequently than did routine dental or medical procedures. They suggest a more effective strategy for preventing endocarditis may be to practice good oral hygiene and get regular dental checkups. They also noted that taking preventive antibiotics carries certain uncommon though possible risks, such as an allergic reaction, and may contribute to growing antibiotic resistance.

Because of these changes, preventive antibiotics are no longer recommended for many people with a patent ductus arteriosus. However, some people still need antibiotics, such as those who:

• Have other heart conditions or artificial valves
• Have a large defect that's causing a low blood oxygen level
• Have had repair with prosthetic material

If you've been told you or your child needed to take antibiotics before any procedures in the past, talk with your doctor about how these new recommendations apply to you.

In most cases, you can't do anything to prevent having a baby with a heart defect. However, it's important to do everything possible to have a healthy pregnancy. Here are the basics:

• Get 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, be sure you talk to your doctor about any medications you're taking.
• Eat a well-balanced diet. Include a vitamin supplement that contains folic acid. Also, limit caffeine.
• 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 illicit drugs. Also, avoid X-rays, hot tubs and saunas.
• Avoid infections. Be sure you are up to date on all of your vaccinations before becoming pregnant. Certain types of infections can be harmful to a developing fetus.
• Keep diabetes under control. If you have diabetes, work with your doctor to be sure its well controlled before and after getting pregnant.

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

If your child has a congenital heart defect, or has had surgery to correct one, you may have some concerns about how best to care for your child. Here are some issues you may be thinking about:

• Preventing infection. In some cases, a child who has congenital heart disease may need to take preventive antibiotics before certain dental and surgical procedures. Your doctor will help you learn if this is necessary. But for most kids with a single heart defect, maintaining good oral hygiene and getting regular dental checkups is the best way to help prevent infection.
• Exercising and play. Parents of children with congenital heart defects often worry about the risks of rough play and vigorous activity even after successful treatment. Although some children may need to limit the amount or type of exercise, many can lead normal or near-normal lives. Your doctor can advise you about which activities are safe for your child.