Tricuspid Atresia

What is tricuspid atresia?

Anatomy of the heart, normal

Tricuspid atresia (TA) is a congenital (present at birth) heart defect that occurs due to abnormal development of the fetal heart beginning during the first eight weeks of pregnancy. The tricuspid valve, normally located between the right atrium and the right ventricle, does not develop properly during pregnancy.

Normally, oxygen-poor (blue) blood returns to the right atrium from the body, travels to the right ventricle, then is pumped through the pulmonary artery into the lungs where it receives oxygen. Oxygen-rich (red) blood returns to the left atrium from the lungs, passes into the left ventricle, and then is pumped through the aorta out to the body.

In tricuspid atresia, however, the following occurs:

  • Improper development of the tricuspid valve. The tricuspid valve does not form at all, and instead a plate of tissue is present in its place. This plate of tissue prevents oxygen-poor (blue) blood from passing from the right atrium to the right ventricle and on to the lungs as it should.
  • The right ventricle is often underdeveloped.
  • Openings may be present in the atrial and ventricular walls (atrial and ventricular septal defects), allowing oxygen-poor (blue) blood and oxygen-rich (red) blood to mix with each other.
  • A patent ductus arteriosus allows blood to pass through from the aorta to the pulmonary artery and receive oxygen from the lungs.
Anatomy of a heart with tricuspid atresia

Tricuspid atresia makes up a small percentage of all cases of congenital heart disease and occurs in about ;five of every 100,000 births.One in five babies born with tricuspid atresia will have some other heart problem as well. TA occurs equally in boys and girls.

Prevention & Risk Treatment

Prevention & Risk Treatment

What causes tricuspid atresia?

The heart is forming during the first eight weeks of fetal development. In TA, during the middle of this development period, the tricuspid valve does not develop properly. Ventricular development is influenced by blood flowing through it, and since no blood is able to pass through the tricuspid valve, the right ventricle remains small.

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

Why is tricuspid atresia a concern?

This heart defect causes children to be cyanotic (blue) since a combination of oxygen-poor (blue) and oxygen-rich (red) blood leaves the heart and goes to the body. Just how much oxygen or how little oxygen will be in the bloodstream depends on a number of factors. Some children will only be mildly cyanotic, while others will not have enough oxygen in the blood to meet the body's needs.

What are the symptoms of tricuspid atresia?

Symptoms are noted shortly after birth. The following are the most common symptoms of tricuspid atresia. However, each child may experience symptoms differently. Symptoms may include:

  • Blue color of the skin, lips, and nail beds (cyanosis)
  • Rapid breathing
  • Labored breathing 
  • Rapid heart rate

The symptoms of TA may resemble other medical conditions or heart problems. Always consult your child's doctor for a diagnosis.



How is tricuspid atresia diagnosed?

A pediatric cardiologist and/or a neonatologist may be involved in your child's care. A pediatric cardiologist specializes in the diagnosis and medical management of congenital heart defects, as well as heart problems that may develop later in childhood. A neonatologist specializes in illnesses affecting newborns, both premature and full-term.

Cyanosis is the major indication that there is a problem with your newborn. Your child's doctor may have also heard a heart murmur during a physical examination. In this case, a heart murmur is a noise caused by the turbulence of blood flowing through the openings that allow the blood to mix or across an obstructed pulmonary valve.

Diagnostic testing for congenital heart disease varies by the child's age, clinical condition, and institutional preferences. Some tests that may be recommended include the following:

  • Chest X-ray. A diagnostic test that uses invisible X-ray beams to produce images of internal tissues, bones, and organs onto film.
  • Electrocardiogram (ECG or EKG). A test that records the electrical activity of the heart, shows abnormal rhythms (arrhythmias or dysrhythmias), and detects heart muscle stress.
  • Echocardiogram (echo). A procedure that evaluates the structure and function of the heart by using sound waves recorded on an electronic sensor that produce a moving picture of the heart and heart valves. 
  • Cardiac catheterization. A cardiac catheterization is an invasive procedure that gives very detailed information about the structures inside the heart. Under sedation, a small, thin, flexible tube (catheter) is inserted into a blood vessel in the groin, and guided to the inside of the heart. Blood pressure and oxygen measurements are taken in the four chambers of the heart, as well as the pulmonary artery and aorta. Contrast dye is also injected to more clearly visualize the structures inside the heart.
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Jeanne Ricks' Story

Jeanne Ricks

Jeanne Ricks, BSN, MS, RN, NE-BC, Director of Outpatient Nursing and Ambulatory Services in Children's National's Heart Institute, said she was meant to be a nurse.

Read More of Jeanne Ricks' Story