Tricuspid Atresia: Symptoms, Causes, Diagnosis, and Treatment Explained
Updated: 2 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: September 2026
Editorial note: This article is for educational purposes only. It is not medical advice. Serious congenital heart conditions require care from qualified pediatric cardiology professionals — always consult your child's health care team for diagnosis and treatment decisions. Last updated: August 2026.
TL;DR
Tricuspid atresia is a congenital heart defect present at birth in which the tricuspid valve never forms, blocking blood flow between the heart's right chambers. It affects about 1 in 12,500 U.S. babies each year — roughly 296 infants [3]. Symptoms like blue or gray skin, breathing difficulty, and poor feeding appear soon after birth. Treatment requires a staged path of multiple surgeries, usually ending with the Fontan procedure at ages 2–5. With surgery, most children live well into adulthood [1].
Quick Answer
Tricuspid atresia is a congenital heart defect where the tricuspid valve is missing, so blood cannot flow from the right atrium to the right ventricle. It occurs in about 1 in 12,500 U.S. births and is considered a critical congenital heart defect. Babies show blue or gray skin, breathing trouble, and poor feeding soon after birth. Treatment is not a single fix but a planned series of surgeries — a shunt in the first two weeks of life, the Glenn procedure in infancy, and the Fontan procedure between ages 2 and 5. Most children who complete treatment grow up to lead full lives with lifelong cardiology follow-up [1] [3] [4].
What is tricuspid atresia?
Tricuspid atresia is a heart problem present at birth, known as a congenital heart defect. The tricuspid valve — the gate between the heart's two right chambers — is never formed. Instead, a solid sheet of tissue blocks blood flow between the right chambers. This forces the right lower chamber (the right ventricle) to stay small and underdeveloped, and it limits how blood moves through the heart [1].
The condition is also called tricuspid valve atresia or TV atresia. It is ranked as the third most common cyanotic congenital heart disease — "cyanotic" meaning it causes low blood oxygen levels and bluish skin coloring. It affects about 1.2 children per 10,000 live births, with no gender preference [4].
Because blood cannot follow its normal route, it must find detours. In most babies, blood crosses from the right upper chamber to the left upper chamber through a hole between the walls — either a structural defect called an atrial septal defect (ASD) or a natural fetal opening called the foramen ovale. From there, the mixed blood moves through the left side of the heart, the body's main pump, and out to the body [1] [3].
The public health scale is small but significant. In the United States, about 1 in 12,500 babies — roughly 296 infants per year — is born with tricuspid atresia [3].
What are the symptoms of tricuspid atresia?
Symptoms usually appear soon after birth because the body is not receiving enough oxygen-rich blood. The signs caregivers and doctors see most often are directly tied to low oxygen levels and the heart working harder than it should [1] [3].
Symptom | What it looks like | Why it happens |
Blue or gray skin and lips (cyanosis) | Bluish tint to skin, lips, and nail beds | Low oxygen levels in the blood |
Difficulty breathing | Fast or labored breathing | Lungs receive less blood flow than normal |
Tiring easily during feedings | Baby stops feeding, rests often, eats slowly | The heart works harder, using up energy |
Slow growth and poor weight gain | Below-expected weight and length curves | Feeding fatigue limits calorie intake |
Some children also develop heart failure symptoms as the condition progresses. These include fatigue and weakness, shortness of breath, swelling in the legs, ankles, and feet, swelling of the belly area (a condition called ascites), and sudden weight gain from fluid buildup [1].
When should you see a doctor?
Serious congenital heart defects like tricuspid atresia are typically diagnosed before birth or within hours of delivery, so most families never have to wait for a decision about seeking care. Modern newborn pulse oximetry screening — a painless oxygen sensor on the hand or foot — can flag low oxygen levels before any symptom appears [2] [3].
Still, you should contact your health care provider right away if you notice any of these signs in your baby [1]:
Warning sign | What to look for |
Skin color change | Blue or gray tint to skin, lips, or nail beds |
Breathing trouble | Rapid, labored, or unusually quiet breathing |
Feeding problems | Tiring quickly, sweating, or refusing feeds |
Growth concerns | Slow growth or poor weight gain |
A doctor may also hear a heart murmur — an abnormal "whooshing" sound caused by blood not flowing in its usual path — during a routine exam [2] [3].
What causes tricuspid atresia?
Most congenital heart defects, including tricuspid atresia, result from changes that occur early in pregnancy as the baby's heart is forming. The exact cause is usually unknown [1].
How a normal heart works
Understanding the defect is easier when you see the normal design. A healthy heart has four chambers and four valves working in sequence [1]:
Chamber | Position | Main job |
Right atrium | Upper right | Receives oxygen-poor blood from the body |
Right ventricle | Lower right | Pumps oxygen-poor blood to the lungs through the pulmonary arteries |
Left atrium | Upper left | Receives oxygen-rich blood back from the lungs |
Left ventricle | Lower left | The main pumping chamber; pushes blood out through the aorta to the body |
Valves act as one-way gates. They open to let blood move into the next chamber or artery, then close to stop it flowing backward [1].
What goes wrong in tricuspid atresia
In tricuspid atresia, the tricuspid valve gate is missing entirely. A sheet of tissue seals the passage between the right atrium and right ventricle, so the right side of the heart can no longer pump blood to the lungs. Blood must reroute: it flows from the right upper chamber across a hole into the left upper chamber, then continues through the left side of the heart [1].
Two structural variations shape how blood reaches the lungs after that [1] [3]:
Scenario | How blood reaches the lungs | Potential problem |
Through the ductus arteriosus | A temporary fetal blood vessel carries blood from the aorta to the lungs; it normally closes after birth | If it closes before surgery, blood flow to the lungs drops sharply |
Through a VSD (ventricular septal defect) | A hole between the lower chambers sends blood directly to the main lung artery | A large VSD sends too much blood to the lungs, risking heart failure |
How much blood reaches the lungs depends on the size of any VSD and whether the pulmonary valve is narrowed. Too little flow means dangerous low oxygen; too much flow strains the heart and lungs [1].
Doctors classify the anatomy into three types, which guides surgery planning [4]:
Type | Share of cases | Defining anatomy |
Type I | 70–80% | Normal relationship of the great arteries |
Type II | 12–25% | D-transposition of the great arteries (D-TGA) |
Type III | 3–6% | Other malposition defects such as truncus arteriosus or double outlet right ventricle |
What increases the risk of tricuspid atresia?
It is not entirely clear why congenital heart defects such as tricuspid atresia occur, but several risk factors have been identified [1].
Tricuspid atresia is notably more common in babies with Down syndrome. Research shows many babies born with this genetic disorder have the condition [1]. Beyond that, several factors during pregnancy can raise the risk [1]:
Risk factor | How it affects risk |
Rubella (German measles) or another viral illness in early pregnancy | Viral infections may disrupt early heart formation |
Family history of congenital heart disease | Some inherited patterns raise risk |
Drinking alcohol during pregnancy | Increases overall congenital defect risk |
Smoking before or during pregnancy | Tobacco exposure affects fetal heart development |
Poorly controlled diabetes during pregnancy | High blood sugar interferes with organ formation |
Certain medications during pregnancy | Some acne, bipolar disorder, and seizure medicines raise risk |
The good news: no significant familial recurrence pattern has been confirmed in most cases, and the condition affects boys and girls equally [4].
What are the complications of tricuspid atresia?
The most serious complication is hypoxemia — a life-threatening lack of oxygen reaching the body's tissues. Because blood flow to the lungs is restricted and the right lower chamber is small and underdeveloped, untreated hypoxemia can quickly become dangerous [1].
Prompt treatment greatly improves outcomes, but long-term complications can still develop as children grow. These are monitored for at every follow-up visit [1]:
Complication | What it means |
Easy tiring during activity | Reduced stamina during play and exercise |
Irregular heart rhythms | The surgically rerouted heart may beat erratically |
Kidney or liver disease | Reduced blood flow can strain these organs |
Heart failure | The single working ventricle can weaken over time |
Without surgical intervention in the first year of life, tricuspid atresia carries a high mortality rate — which is why it is classified as a critical congenital heart defect requiring rapid treatment [3] [4].
Is tricuspid atresia preventable?
Because the exact cause of most congenital heart defects is unknown, it may not be possible to prevent tricuspid atresia in most cases [1].
However, families with specific risk factors can take concrete steps. If you have a family history of congenital heart defects or are at high risk of having a child with one, genetic screening before or during pregnancy may be recommended. Talking with a genetic counselor and a pediatric heart specialist helps you understand your personal risk [1].
Everyday steps that lower the overall risk of congenital heart defects include [1]:
Preventive step | Why it helps |
Get proper prenatal care | Regular checkups keep mother and baby healthy |
Take 400 micrograms of folic acid daily | Proven to reduce brain and spinal cord birth defects; may help reduce heart defect risk too |
Get the rubella (German measles) vaccine | Rubella infection during pregnancy can affect heart development — vaccinate before trying to conceive |
Check all medications with your provider | Some prescription and over-the-counter medicines can harm the baby |
Do not smoke or drink alcohol during pregnancy | Both increase congenital defect risk |
Avoid chemical exposure | Stay away from cleaning products and paint as much as possible while pregnant |
Manage other health conditions | Work with your provider on the safest way to treat conditions like diabetes |
How is tricuspid atresia diagnosed?
Tricuspid atresia may be spotted during a routine pregnancy ultrasound before birth — another reason proper prenatal care matters so much. The diagnosis is then usually confirmed with a more detailed fetal echocardiogram [2] [3].
After birth, a health care provider examines the baby immediately, listening to the heart and lungs. Tricuspid atresia becomes a suspect when a newborn has blue or gray skin, trouble breathing, or a heart murmur [2].
A set of diagnostic tests confirms the picture. Each one contributes different information [2]:
Test | How it works | What it reveals |
Echocardiogram | Sound waves create moving images of blood flow through the heart and valves | The missing tricuspid valve, irregular blood flow, and any other heart problems |
Electrocardiogram (ECG/EKG) | Records the heart's electrical activity | Heart rate and irregular rhythms |
Pulse oximetry | A small sensor on a hand or foot | Oxygen level in the blood — simple and painless |
Chest X-ray | Standard imaging of the chest | Heart size, chamber size, and fluid in the lungs |
Cardiac catheterization | A thin, flexible tube guided from the groin into the heart | Chamber pressures and detailed anatomy via dye contrast |
Cardiac catheterization is rarely used for the initial diagnosis. It is more often done to map the heart's anatomy and pressures before surgery [2].
What treatments are available?
There is no way to replace a tricuspid valve in tricuspid atresia. Instead, treatment is a planned series of surgeries that reroute blood flow so the lungs receive enough blood and the body gets enough oxygen. Medications manage symptoms along the way [2].
If your child is diagnosed, experts recommend care at a medical center where surgeons and staff have deep experience with complex congenital heart disease [2].
Medications and supportive care
Medications play a supporting but essential role [2]:
Medication purpose | Example use |
Strengthen the heart muscle | Helps the single working ventricle pump effectively |
Lower blood pressure | Reduces strain on the heart and vessels |
Remove excess fluid | Diuretics ease swelling and fluid buildup |
Supplemental oxygen | Helps the baby breathe more comfortably |
Prostaglandin | Given before surgery to keep the ductus arteriosus open, preserving blood flow to the lungs |
The surgical pathway
Most babies with tricuspid atresia need several surgeries or procedures. Some are temporary fixes that buy time until a permanent correction can be made. The type of surgery depends on the baby's specific anatomy [2] [3]:
Procedure | When it happens | What it does |
Shunting | Usually within the first two weeks of life | Creates a new pathway (shunt) redirecting blood from a main vessel to the lungs, raising blood flow and oxygen levels |
Atrial septostomy | Rarely, early in life | A balloon creates or enlarges the opening between the upper chambers so more blood can cross over |
Pulmonary artery band | When a VSD sends too much blood to the lungs | A band around the main lung artery reduces excess lung blood flow |
Glenn procedure | After the first shunt, as lung pressures fall with age | Removes the shunt and connects a large vein directly to the lung artery, reducing strain on the lower left chamber |
Fontan procedure | Typically at ages 2–5 | Creates the permanent pathway so most blood that would have gone to the right heart flows directly into the pulmonary artery |
The shunt is a temporary bridge — babies usually outgrow it and may need another surgery to replace it. The Glenn procedure sets the stage for the Fontan, which is the definitive operation. Short- and intermediate-term outlook after the Fontan is generally promising, though regular checkups are essential to monitor for complications such as heart failure [2].
The CDC is careful to note that these surgical repairs are not a cure — lifelong cardiology care is part of the treatment plan [3].
What is life like after surgery?
Many children with congenital heart defects like tricuspid atresia grow up to lead full lives. But the journey does not end at the operating table. It becomes a rhythm of structured follow-up [2].
After treatment, babies need regular checkups — ideally with a pediatric congenital cardiologist, a doctor trained in children's congenital heart conditions. As adults, they transition to an adult congenital cardiologist for lifelong monitoring [2].
Day-to-day self-care focuses on five areas [2]:
Self-care area | Practical guidance |
Feeding | Frequent, small feedings; breast milk is excellent, but a special high-calorie formula may be needed; some babies need a feeding tube |
Infection prevention | Ask about preventive antibiotics before dental and other procedures to guard against infective endocarditis; keep up good oral hygiene |
Physical activity | Stay as active as tolerated or as the provider recommends, with plenty of rest |
Sports limits | Some exercise types may need limits — ask your provider about specific restrictions |
Vaccinations | Standard immunizations plus flu, COVID-19, pneumonia, and RSV vaccines |
At least yearly appointments with a pediatric congenital cardiologist are the standard [2].
Can adults with tricuspid atresia have children?
Adults treated for tricuspid atresia who are pregnant or hoping to be should work with an adult congenital heart disease specialist and a maternal-fetal medicine specialist [2].
Pregnancy is considered high risk for people who have had a Fontan procedure. Those with a history of heart failure may be discouraged from becoming pregnant at all. Specialist guidance before conception is essential [2].
How do you prepare for a doctor's appointment?
If your child has a life-threatening congenital heart defect, diagnosis usually comes soon after birth — sometimes before birth on a pregnancy ultrasound. If a defect was not recognized at birth, bring your concerns to your child's health care provider. Be ready to describe symptoms and share your family medical history, since some congenital heart defects run in families [2].
You will likely be referred to a heart doctor specializing in pediatric or adult congenital heart disease. Before the appointment, gather the following [2]:
What to bring | Details |
Symptoms observed | Everything you have noticed in yourself or your child, even items that seem unrelated |
Personal information | Family history of congenital heart disease; lifestyle choices during pregnancy (smoking, alcohol); illnesses during pregnancy |
Questions for the provider | Prepared in advance to make the most of the visit |
Medications | All prescriptions and over-the-counter medicines, including dosages |
If possible, bring a family member or friend — someone who can help you remember what the provider says [2].
Questions to ask
Coming prepared with questions helps you and your health care team use the appointment well [2]:
# | Question |
1 | What tests are needed? |
2 | What treatments are available, and which do you recommend? |
3 | Will this require more than one surgery? |
4 | How can I make myself or my child more comfortable? |
5 | Are there restrictions to follow? |
6 | If I get pregnant again, is there a way to prevent tricuspid atresia from happening? |
7 | Are there brochures or other printed material I can have? |
8 | What websites do you recommend? |
What the doctor will ask you
Being ready for the provider's questions saves time for what matters most to you [2]:
Provider's question | Why it matters |
Can you describe the symptoms? | Establishes the clinical picture |
When do symptoms occur? | Links symptoms to activity or feeding |
Do symptoms come and go? | Patterns hint at severity |
Are symptoms getting worse? | Tracks progression |
Does anything make symptoms better? | Reveals what already helps |
Family history of congenital heart defects? | Checks for inherited patterns |
Is your child growing and meeting milestones? | Growth reflects how well the heart is coping |
The bottom line
Tricuspid atresia is a serious congenital heart defect — the tricuspid valve never forms, and blood must find new routes through the heart. It affects roughly 1 in 12,500 babies born in the United States each year, about 296 infants [3].
But the outlook has changed dramatically with modern treatment. Most babies who receive the staged surgical pathway — early shunt, Glenn procedure, then Fontan between ages 2 and 5 — live well into adulthood and grow up to lead full lives [1] [2].
The practical takeaways are clear. Recognize the signs early: blue or gray skin, breathing difficulty, feeding fatigue, and poor growth. Seek care at a center experienced in complex congenital heart disease. Commit to the follow-up schedule — at least yearly with a pediatric congenital cardiologist in childhood, and lifelong cardiology care in adulthood [1] [2] [3].
If your baby shows blue or gray coloring, struggles to breathe, or tires quickly during feedings, contact your health care provider immediately — early treatment is the single most important factor in a strong outcome.
Frequently Asked Questions
What is tricuspid atresia?
It is a congenital heart defect present at birth in which the tricuspid valve between the heart's right upper and lower chambers never forms. A solid sheet of tissue blocks blood flow, leaving the right ventricle underdeveloped [1].
How common is tricuspid atresia?
About 1 in 12,500 babies in the United States — roughly 296 infants per year — is born with the condition. It is the third most common cyanotic congenital heart disease [3] [4].
What are the signs of tricuspid atresia in a newborn?
Symptoms appear soon after birth and include blue or gray skin and lips, difficulty breathing, tiring easily (especially during feedings), and slow growth or poor weight gain [1] [3].
Is tricuspid atresia curable?
No single cure exists — the missing valve cannot be replaced. But a planned series of surgeries reroutes blood flow, and most children who complete treatment live well into adulthood [1] [2].
How many surgeries does a child with tricuspid atresia need?
Most children need several. A shunt is placed in the first two weeks of life, the Glenn procedure follows in infancy, and the definitive Fontan procedure is typically done between ages 2 and 5 [2].
What is the Fontan procedure?
The final corrective surgery, usually performed when a child is 2 to 5 years old, that creates a pathway so blood that would have gone to the right heart flows directly into the pulmonary artery. Short- and intermediate-term outcomes are generally promising [2].
Can tricuspid atresia be prevented?
In most cases the cause is unknown, so it cannot be reliably prevented. Steps like prenatal care, folic acid (400 micrograms daily), the rubella vaccine before pregnancy, and avoiding smoking and alcohol during pregnancy lower the overall risk of congenital heart defects [1].
What is life expectancy after tricuspid atresia treatment?
Most babies with tricuspid atresia who undergo surgery live well into adulthood and lead full lives. Lifelong checkups with a congenital cardiologist are necessary to monitor for complications such as heart failure [1] [2].
References
Mayo Clinic — Tricuspid atresia: Symptoms & causes (updated Jan. 21, 2025)
Mayo Clinic — Tricuspid atresia: Diagnosis & treatment (updated Jan. 21, 2025)
CDC — Tricuspid Atresia, Congenital Heart Defects (updated Jan. 9, 2026)
American Academy of Pediatrics — Congenital heart defects: Know the facts
National Heart, Lung, and Blood Institute — Congenital heart defects
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