Pulmonary atresia (PA)

It’s natural for you to be concerned right now about your child’s health—a diagnosis of pulmonary atresia can be overwhelming. But you can rest assured that at Children’s Hospital Boston, your child is in expert hands.

What are the forms of pulmonary atresia?

There are two major variations in pulmonary atresia, usually characterized by the presence or absence of a hole (ventricular septal defect, or VSD) between the right and left ventricles:

• pulmonary atresia with intact ventricular septum (PA/IVS): If there’s no VSD, the right ventricle receives little blood flow before birth and can become significantly underdeveloped.
  
  Severe underdevelopment of the right ventricle makes it incapable of performing its role as a pumping chamber. The blood vessels that provide fresh blood to the heart muscle may also develop abnormally.
   
• pulmonary atresia with ventricular septal defect (PA with VSD): There may be an abnormal opening in the ventricular wall (septum) called a ventricular septal defect (VSD)—that allows blood in the right ventricle a way out to the body. The presence of the VSD may also help the right ventricle maintain size. PA with VSD is related to another condition called tetralogy of Fallot.

 PA/IVS and PA with VSD are the two major types of pulmonary atresia. Both variations exist on a spectrum of severity, and each one has its own options for treatment. 

Are there additional defects associated with PA?

Like many congenital heart conditions, pulmonary atresia isn’t a single defect, but rather a cluster of associated defects. Two additional holes usually close after birth, but are now important as temporary alternative openings for blood flow through the baby’s heart to his body and lungs:

• A natural opening between the right and left atria, called the foramen ovale, normally shuts at birth, but may stay open in this situation, allowing oxygen-poor (blue) blood to pass from the right atrium to the left atrium, then to the left ventricle, out the aorta, to the body.
   
• Newborns also have another natural connection between the aorta and the pulmonary artery—called the ductus arteriosus. The ductus arteriosus normally closes within a few hours or days after birth. Medication can help keep this opening open (patent). In PA, a patent ductus arteriosis will allow some blood to pass from the aorta to the pulmonary artery and on through the lungs to pick up oxygen.

Why is pulmonary atresia a concern?

Before birth, while the fetus is developing, pulmonary atresia isn’t a problem because the placenta provides oxygen for the baby. But once a baby is born, his lungs must provide the oxygen needed for survival. In children with pulmonary atresia, because there’s no opening on the pulmonary valve, blood cannot to get to the lungs and become oxygenated.

In PA, the abnormal development of the pulmonary valve prevents oxygen-poor (blue) blood from passing from the right atrium to the right ventricle and on to the lungs for oxygenation as it should. In this situation, blue blood will pass from the right atrium across the foramen ovale to the left atrium and ultimately out to the body, causing the characteristic “blueness” seen in babies with PA.

This situation is life-threatening, since the body requires oxygenated blood for survival, and oxygen-poor (blue) blood cannot meet the body’s demands.

What are the signs and symptoms of PA?

Signs and symptoms of PA are clear shortly after a baby’s birth. The obvious sign of PA is a newborn who becomes cyanotic (blue) in the transitional first day of life, when the maternal source of oxygen (from the placenta) is removed. The degree of cyanosis is related to the presence of other defects that allow blood to mix, including a patent (open) ductus arteriosus.

Besides cyanosis (“blue baby syndrome”), the most common symptoms of pulmonary atresia are lethargy and pale, cool or clammy skin.

If your baby’s pediatrician notices any of these symptoms, the doctor may refer you to a pediatric cardiologist (and/or neonatologist) for immediate testing, diagnosis and a determination of treatment.

How do you diagnose PA?

Most babies with PA show symptoms on the day they’re born. Others show symptoms in the first few days of life. If your newborn baby was born with a bluish tint to his skin, or if he’s having difficulty breathing, your pediatrician may refer you to a pediatric cardiologist (and/or neonatologist), who will perform a physical exam.

Your Children’s cardiologist will detect a heart murmur, measure blood oxygen levels (non-invasively) and order diagnostic testing, which could include EKG, cardiac ultrasound, cardiac MRI, cardiac catheterization or chest x-ray. (PA is sometimes diagnosed before birth by a prenatal ultrasound done by your obstetrician.)

How do you treat PA/IVS?

Catheterization. Treatment of pulmonary atresia with intact ventricular septum depends on the degree of undevelopment of the right ventricle (RV) and associated abnormalities. All babies with PA/IVS undergo cardiac catheterization to further define the heart’s anatomy. Some babies may be candidates for balloon dilation of the pulmonary valve in the catheterization lab.

Surgery. In other babies, the RV may be too small, or associated abnormalities may exist that preclude opening the valve in the catheterization lab. Infants with this more severe form of PA/IVS are treated with a series of surgeries performed in the baby’s first few years. The goal of these surgeries is to re-route blood flow so that enough oxygen is added to the baby’s bloodstream to meet his body’s needs.

Your child most likely will be admitted to Children’s cardiac intensive care unit (CICU) once symptoms are noted. Initially, he may be placed on oxygen, and possibly a ventilator, to help his breathing. We may give him IV (intravenous) medications to help his heart and lungs function more efficiently.

Important aspects of initial treatment—that allow time for the baby to stabilize —include the following:

• A cardiac catheterization procedure is usually performed to evaluate the defect(s), whether the foramen ovale and/or ductus arteriosus are still open, and the amount of blood that is mixing.
• An intravenous medication called prostaglandin E1 is given to keep the ductus arteriosus from closing.
• If the anatomy is favorable, a catheter may be used to open the atretic (unopened) pulmonary valve to allow blood flow to the lungs.

Ultimately, for patients with a more severe form of PA/IVS, surgery will be necessary to improve permanent blood flow to the lungs. A series of three staged operations—called the Fontan sequence—may be needed, starting shortly after birth and concluding when a child is a few years old. The operations will redirect blood flow to the lungs and body through various surgical connections.

Will my child be OK after surgical repair for pulmonary atresia?

The outlook varies from child to child, but open heart surgery at Children’s has among the highest success rates in the United States among large pediatric cardiac centers.

Your child may need multiple operations or catheterizations to replace conduits or revise a palliation as your infant grows older. After each procedure, your child will need to be followed by a Children’s pediatric cardiologist, who will make adjustments to medications, assist you with feeding problems, measure oxygen levels, and determine when/if it’s time for another procedure.

Note: Infants who’ve had initial surgery for a single ventricle defect are typically enrolled in Children’s Home Monitoring Program between the baby’s Stage I and Stage II operations in the Fontan sequence.

What causes pulmonary atresia?

The heart starts to form during the first eight weeks of fetal development. In PA, during this development period the pulmonary valve doesn’t develop properly.

Some congenital heart defects may have a genetic link, either due to a defect in a gene or a chromosome abnormality—causing heart problems to occur more often in certain families. Most often, though, this heart defect occurs sporadically (by chance), with no clear reason for its development.

It’s important for parents to understand that you’ve done nothing to cause your baby’s pulmonary atresia and its accompanying defects. Nothing you’ve ingested or have been exposed to environmentally has been definitively be linked to having a baby with PA.

How common is PA?

Pulmonary atresia affects one out of every 10,000 babies. While relatively rare, it’s the tenth most common form of congenital heart disease in newborns. It occurs slightly more often in boys than girls.

Will my baby be OK in the medium- and longer-term?

Your cardiologist will help you create a long-term care program as your baby matures into childhood, the teen years and even adulthood. Most people who have had congenital heart disease will have an ongoing relationship with their Children’s cardiologist. We’ll prevent and treat complications, and will advise on daily-life issues, such as exercise and activity levels, nutrition and precautions related to pregnancy.

Surgical techniques for treating PA and its associated defects are continually being refined, and surgical success rates at Children’s are very high. Nevertheless, your child will need lifelong monitoring and medication, since he may be at some risk for arrhythmias, infections, leaky valves, heart failure or stroke.

Non-cardiac surgeries and, for females, pregnancy do pose major risks and will require careful evaluation and discussion with a cardiologist.

Where can my child find care and support when he grows up?

• The Boston Adult Congenital Heart and Pulmonary Hypertension Service (BACH) provides long-term inpatient and outpatient care and advanced therapeutic options for patients with congenital heart disease and pulmonary hypertension as they reach and progress through adulthood.
  
  BACH is an international center for excellence, with physicians and services from Children’s, Brigham and Women’s Hospital and Beth Israel Deaconess Medical Center. The center promotes and supports clinical and scientific research for the advancement of care of these patients, and is a leader in the education of providers caring for this unique population.
   
• The Adult Congenital Heart Association (ACHA) is a national not-for-profit organization dedicated to improving the quality of life—and extending the life—of adults with congenital heart defects. The organization serves and supports many of the adults with congenital heart defects (now thought to number as many as one million), their families and the medical community, as well as conducting research and providing advocacy, outreach and education.

FAQ

Q: What is pulmonary atresia (PA)?

A: The pulmonary valve has three one-way leaflets that allow blood to flow into the pulmonary artery. With pulmonary atresia, abnormal valve development prevents these leaflets from opening; therefore, blood cannot flow forward from the right ventricle to the lungs to get oxygenated.

Q: Are there different types of pulmonary atresia?

A: The two types of PA are:

• pulmonary atresia with intact ventricular septum (PA/IVS): If there’s no opening in the ventricular wall (septum)—called a ventricular septal defect or VSD—the right ventricle receives little blood flow before birth and does not develop fully.
   
• pulmonary atresia with ventricular septal defect (PA with VSD): An abnormal opening in the ventricular wall (septum)—called a ventricular septal defect or VSD—allows blood in the right ventricle a way out. This is a severe form of the defect related to tetralogy of Fallot.

Q: If my child has PA/IVS, will he be OK?

A: Open heart surgery at Children’s Hospital Boston has among the highest success rates in the United States among large pediatric cardiac centers. While very serious, pulmonary atresia is treatable surgically, and recent surgical advances have greatly improved your child’s outlook for success.

Q: How does Children’s treat PA?

A: Initial stabilization of your baby usually happens with medications and catheterizations. In your baby’s first few years, the skilled surgeons at Children’s will usually treat pulmonary atresia with a series of surgeries that re-route blood flow so that enough oxygen is added to the baby’s bloodstream to meet his body’s needs.

Q: What are the symptoms of PA?

A: Most babies with PA show symptoms on the day they’re born. Others show symptoms in the first few days of life. These include:

• blue color of the skin, lips and nailbeds (cyanosis, “blue baby”)
• lethargy
• pale, cool or clammy skin
• disinterest in feeding or tiring while feeding

If your child has any of these symptoms, your pediatrician may refer you to a pediatric cardiologist for immediate testing, diagnosis and a determination of treatment.

Q: If my child has PA, what should I ask my Children’s doctor?

A: After your child is diagnosed with PA, you may feel overwhelmed with information. It can be easy to lose track of the questions that occur to you. Lots of parents find it helpful to jot down questions as they arise—that way, when you talk to your child’s doctors, you can be sure that all of your concerns are addressed.

Some of the questions you may want to ask include:

• What tests will you perform to further diagnose my child?
• What actions might you take after you reach a diagnosis?
• Are there alternative therapies?
• Will my child be OK if he has congenital heart disease?
• Will there be restrictions on my child’s activities?
• Will there be long-term effects?
• What can we do at home?

Q: When is PA usually diagnosed, and how?

A: Most babies with PA show symptoms on the day they’re born. Others show symptoms in the first few days of life. If your newborn baby was born with a bluish tint to his skin, your pediatrician may refer you to a pediatric cardiologist (and/or neonatologist), who will perform a physical examination.

Your Children’s cardiologist will detect a heart murmur, measure blood oxygen levels (non-invasively) and order diagnostic testing, which could include EKG, cardiac ultrasound, cardiac MRI, cardiac catheterization or chest x-ray. (Some PA may be diagnosed before birth by an ultrasound done by your obstetrician.)

Q: What should we do at home after PA surgery?

A: Consult your child’s cardiologist for guidance on follow-up care—including:

• wound care while your baby is healing
• a nutritional program to encourage weight gain
• an oral hygiene program to prevent infection
• an appropriate exercise regimen to build body mass and achieve fitness

Your child may need multiple surgeries or catheterizations in his early years. As he recovers and grows, be sure to follow a regular program of well-baby/well-child checkups.

Q: What is the long-term outlook for PA-affected children?

A: Surgical techniques for PA and its associated defects are continually being refined, and the long-term outlook is continually improving. Nevertheless, your child will need lifelong monitoring and possibly medication, since he may be at some risk for arrhythmias, infections, leaky valves, heart failure or stroke.

Q: What causes PA?

A: Pulmonary atresia occurs due to the abnormal development of the heart’s pulmonary valve during the first eight weeks of fetal growth. It’s important for parents to understand that you’ve done nothing to cause your baby’s pulmonary atresia and its accompanying defects. Nothing you’ve ingested or have been exposed to environmentally has been definitively linked to having a baby with PA.

Most often, this heart defect occurs sporadically (by chance), with no clear reason for its development.

Q: What is Children’s’ experience treating congenital heart defects?

A: Children’s surgeons treat some of the most complex pediatric heart conditions in the world, with overall success rates approaching 98 percent—among the highest in the nation among large pediatric cardiac centers.

Our experts have pioneered some of medical science’s most advanced heart treatments, now in use around the globe. Children’s is among the only major pediatric heart centers in the world performing fetal heart interventions for certain congenital defects.

Q: What heart research and innovations are coming from Children’s?

A: A significant amount of Children’s groundbreaking cardiac research aims to refine and advance the open heart surgery and catheterization procedures that treat congenital heart defects in newborns and young children—including pulmonary atresia. Children’s Cardiac Surgery Research Laboratory is studying the mechanisms of heart disease and new treatments for children with congenital heart defects.

Learn more about Children’s cardiac research initiatives and Children’s current projects in cardiology research.

Causes

Pulmonary atresia occurs due to the abnormal development of the heart’s pulmonary valve during the first eight weeks of fetal growth. It’s important for parents to understand that you’ve done nothing to cause your baby’s pulmonary atresia and its accompanying defects.

Some congenital heart defects may have a genetic link, causing heart problems to occur more often in certain families. Most often, though, this heart defect occurs sporadically (by chance), with no clear reason for its development.

Symptoms

• blue color of the skin, lips and nailbeds (cyanosis, “blue baby”)
• lethargy
• pale, cool or clammy skin
• disinterest in feeding or tiring while feeding

When to seek medical advice

Call your health care provider immediately if your baby or child is having difficulty breathing or is breathing rapidly, has a bluish color or seems to tire too easily.

Questions to ask your doctor

After your child is diagnosed with PA, you may feel overwhelmed with information. It can be easy to lose track of the questions that occur to you. Lots of parents find it helpful to jot down questions as they arise—that way, when you talk to your child’s doctors, you can be sure that all of your concerns are addressed.

Some of the questions you may want to ask include:

• What tests will you perform to further diagnose my child?
• What actions might you take after you reach a diagnosis?
• Are there alternative therapies?
• Will my child be OK if he has congenital heart disease?
• Will there be restrictions on my child’s activities?
• Will there be long-term effects?
• What can we do at home?

Who’s at risk

Congenital heart defects usually occur sporadically (by chance), with no clear reason for their development. So, it’s difficult to predict who’s at risk. Familial cases have been reported, but no genetic link has been confirmed. In general, if you have a child with a congenital cardiac defect, the chance of other children you may have being born with a defect is about 2 to 3 percent.

Complications

The first children who underwent the staged surgical repairs for congenital heart defects are now in their 20s and largely doing well. However, complications can occur, including arrhythmias, blood clots, infections within the heart (endocarditis), leaky valves, easy tiring and loss of protein from the digestive tract. As he grows, it’s important for your child to be closely monitored by his cardiologist.

Long-term outlook

Surgical techniques for PA and its associated defects are continually being refined, and the long-term outlook is continually improving. Nevertheless, your child will need lifelong monitoring and possibly medication, since he may be at some risk for arrhythmias, infections, leaky valves, heart failure or stroke.

For teens

If you’re a teen with a congenital heart defect, you have a lot to cope with. Besides the typical issues any teenager faces—from social acceptance to body changes and more—you’ll also have to deal with medical appointments and procedures, some delay of your natural wish for independence, feeling different and assuming a lot of personal responsibility for maintaining your own good health.

If you feel overwhelmed, depressed or anxious through this important time in your transition to adulthood, speak to your doctor or counselor to get help.

For adults

If you were treated for congenital heart disease as a child, you’re probably being followed by your cardiologist, since complications from early heart disease can arise in adulthood.

You may need lifelong monitoring and medication, since you could be at some risk for arrhythmias, blood clots, infections, leaky valves, heart failure or stroke. Going forward, your cardiologist will advise you on activity levels, pregnancy issues and certain lifestyle choices.

Fortunately, Children’s can help adults with congenital heart defects. Many adults who were patients at Children’s as babies or children continue to be monitored by the clinicians who’ve followed them since childhood.

In addition, our Boston Adult Congenital Heart and Pulmonary Hypertension Service (BACH) provides long-term inpatient and outpatient care and advanced therapeutic options for patients with congenital heart disease and pulmonary hypertension as they reach and progress through adulthood.

BACH is an international center for excellence, with physicians and services from Children’s, Brigham and Women’s Hospital and Beth Israel Deaconess Medical Center. The center promotes and supports clinical and scientific research for the advancement of care of these patients, and is a leader in the education of providers caring for this unique population.

What you can do at home

After surgery, your child’s cardiologist will offer recommendations for follow-up care,

including:

• wound care while your baby is healing
• a nutritional program to encourage weight gain
• an oral hygiene program to prevent infection
• an appropriate exercise regimen to build body mass and achieve fitness

Your child may need multiple surgeries or catheterizations in his early years. As he recovers and grows, be sure to follow a regular program of well-baby/well-child checkups.

Prevention

It’s important to understand that as parents, you’ve done nothing to cause PA and its accompanying defects, and there are no precautions you could have taken to prevent it. Congenital heart defects usually occur sporadically (by chance), with no clear reason for their development.

PA glossary

• aorta: one of the heart’s two great arteries. In a normal heart, the aorta arises from the left ventricle and carries oxygen-rich blood out to the body.
   
• atrial septal defect (ASD): a congenital (present at birth) heart defect in which there is an opening in the tissue wall (septum) that divides the two upper chambers of the heart (right and left atria). A patent foramen ovale (PFO) is a type of ASD.
   
• bi-directional Glenn: surgical procedure that frequently replaces the Blalock-Taussig shunt with another connection to the pulmonary artery to provide a path for blue blood to go out to the lungs. The superior vena cava is surgically connected to the right pulmonary artery to direct blood from the upper part of the body to the lungs to receive oxygen. This is the second procedure of the Fontan Sequence.
   
• Blalock-Taussig shunt: a surgical procedure to create a pathway for blood to reach the lungs. A shunt (tube) may be inserted between the aorta or one of its branches and pulmonary artery to increase blood flow. This is frequently the first procedure of the Fontan Sequence.
   
• cardiac catheterization: an invasive diagnostic procedure performed under sedation to obtain detailed visual information and measurements about the structures inside the baby’s heart. Blood pressure and oxygen measurements are taken in the four chambers of the heart, as well as the pulmonary artery and aorta.
  
  Cardiac catheterization can also be an interventional procedure. For some babies with PA, the pulmonary valve may be dilated in the catheterization lab.
   
• cardiac/cardio-: pertaining to the heart
   
• cardiac magnetic resonance imaging (MRI): a non-invasive diagnostic tool using 3-D imaging technology produced by magnets to accurately determine the blood flow and functioning of your child's heart
   
• cardiac surgery: a surgical procedure performed on the heart or one of the blood vessels connected to the heart
   
• cardiac surgeon: a doctor who performs surgery on the heart. A pediatric cardiac surgeon performs surgery on the hearts of infants and children.
   
• cardiologist: a doctor who diagnoses and treats heart problems non-surgically. A pediatric cardiologist treats infants, children and some adults with heart problems.
   
• chest x-ray: a diagnostic tool to evaluate the size and spatial relationships of the heart within the child’s chest
   
• cyanosis (cyanotic): blue color of skin, lips and nailbeds caused by a reduction in the amount of oxygen-rich (red) blood circulating in baby’s bloodstream
   
• congenital heart defect: heart defect present at birth. The heart usually starts to form in the first eight weeks of fetal development. It’s thought that most congenital heart defects develop during this period.
   
• diagnosis: medical determination of illness or disease based on history, physical examinations and advanced technology diagnostic testing tools
   
• echocardiogram (echo, cardiac ultrasound): a diagnostic tool that evaluates the structure and function of the heart using sound waves that produce a moving picture of your child’s heart and heart valves. The ultrasound can be used to understand flow in the different chambers and to estimate pressures.
   
• electrocardiogram (ECG, EKG): a diagnostic tool that evaluates the electrical activity of your child’s heart. An EKG is usually the initial test for evaluating the causes of symptoms and detecting heart abnormalities, including PA.
   
• Fontan sequence: a series of three operations performed on children who have just one full-sized functioning ventricle (a type of single ventricle defect), as with severe PA/IVS. The Fontan operations are usually performed at intervals starting within days or months after birth and ending at a few years of age. The Fontan operation is the third procedure in the Fontan sequence.
   
• hypoplasia (hypoplastic): underdevelopment, as with the right ventricle in PA/IVS
   
• IV: intravenous, into the vein; one method of delivering medication
   
• neonatologist: a doctor who specializes in illnesses affecting newborns, both premature and full-term
   
• PA/IVS: acronym for pulmonary atresia with intact ventricular septum, meaning that there is no ventricular septal defect (VSD) to help provide a mixture of blue and red blood. PA/IVS is considered a single ventricle defect because of associated underdevelopment (hypoplasia) of the right ventricle
   
• PA with VSD: acronym for pulmonary atresia with ventricular septal defect, a hole (septum) in the wall separating the right and left ventricles
   
• PFO (patent foramen ovale): a defect in the wall (septum) between the upper two heart chambers (the left and right atria)
   
• pulmonary artery: one of the heart’s two great arteries, which normally arises from the right ventricle and carries oxygen-poor blood to the lungs, where it receives oxygen
   
• pulmonary atresia: a congenital heart defect in which the pulmonary valve doesn’t open and oxygen-poor blood can’t get through the pulmonary artery to the lungs to pick up fresh oxygen. Other related defects can also occur, including an underdeveloped right ventricle.
   
• pulmonary valve: one of the four valves in the heart, between the right ventricle and the pulmonary artery; allows blood to flow one way to the lungs to pick up oxygen
   
• pulse oximetry: a non-invasive test to measure the amount of oxygen in the blood
   
• shunt: an artificial connection of blood vessels in order to redirect blood to the lungs in children with inadequate flow for oxygenation
   
• single ventricle defect (SVD): one of several congenital (present at birth) heart defects in which the heart has only one fully functioning ventricle. The more severe forms of PA/IVS are considered a single ventricle defect.
   
• sporadic: occurring by chance, occasionally, not inherited
   
• signs and symptoms: the presenting reasons why a child needs medical attention. Characteristics such as onset, quality, triggers and severity help diagnosticians to determine a disease, or to decide which testing is needed to determine the disease.
   
• ventricular septal defect (VSD): a congenital (present at birth) heart defect associated with PA in which there’s an opening in the tissue wall (septum) that divides the two lower chambers of the heart (right and left ventricles)

For in-depth visual information on several of the conditions, diagnostic tools and procedures described above, visit our cardiovascular Multimedia library.