Tricuspid atresia is a type of heart disease that is present at birth (congenital heart disease), in which the tricuspid heart valve is missing or abnormally developed. The defect blocks blood flow from the right atrium to the right ventricle.
Tricuspid atresia is an uncommon form of congenital heart disease that affects about 5 in every 100,000 live births. Twenty percent of patients with this condition will also have other heart problems.
Normally, blood flows from the body into the right atrium, then through the tricuspid valve to the right ventricle and on to the lungs. If the tricuspid valve does not open, the blood cannot flow from the right atrium to the right ventricle. Because of the problem with the tricuspid valve, blood ultimately cannot enter the lungs, where it must go to pick up oxygen (becomes oxygenated).
Instead, the blood passes through a hole between the right and left atrium. In the left atrium, it mixes with oxygenated blood returning from the lungs. This mix of oxygenated and de-oxygenated blood is then pumped out into the body, which causes oxygen levels in the blood to be lower than normal.
The lungs receive blood either through a hole between the right and left ventricles, or through a fetal vessel called the ductus arteriosus that connects the pulmonary artery (artery to the lungs) to the aorta (main artery to the body). The ductus arteriosus is present when a baby is born, but closes by itself shortly after birth.
Bluish color to the skin
Shortness of breath
Exams and Tests
This condition may be discovered during routine prenatal ultrasound imaging or when the baby is examined shortly after birth. Bluish skin is present from birth. A heart murmur is often present at birth and may increase in loudness over several months.
Tests may include the following:
MRI of the heart
Once the diagnosis is made, the baby will often be admitted to the neonatal intensive care unit (NICU). A medicine called prostaglandin E1 may be used to keep the ductus arteriosis open so that blood can circulate to the lungs.
The condition always requires surgery. If the heart is unable to pump enough blood out to the lungs and rest of the body, the first surgery usually occurs within the first few days of life. In this procedure, an artificial shunt is inserted to keep blood flowing to the lungs. In some cases, this first surgery is not needed.
Afterward, the baby usually goes home. The child will need to take one or more daily medicines and be closely followed by a pediatric cardiologist, who will decide when the second stage of surgery should be done.
The next stage of surgery is called the Glenn shunt or Hemifontan procedure. This procedure connects half of the veins carrying blue blood from the upper half of the body directly to the pulmonary artery. The surgery is usually done when the child is between 4 to 6 months old.
During stage I and II, the child may still look blue (cyanotic).
Stage III, the final step, is called the Fontan procedure. The rest of the veins carrying blue blood from the body are connected directly to the pulmonary artery leading to the lungs. The left ventricle now only has to pump to the body, not the lungs. This surgery is usually performed when the child is 18 months to 3 years old. After this final step, the baby is no longer blue.
Usually, surgery will improve the condition.
Irregular, fast heart rhythms (arrhythmias)
Chronic diarrhea (from a disease called protein-losing enteropathy)
Fluid in the abdomen (ascites) and in the lungs (pleural effusion)
Blockage of the artificial shunt
Strokes and other nervous system complications
When to Contact a Medical Professional
Contact your health care provider right away if your infant has:
New changes in breathing patterns
Skin that is turning blue
There is no known way to prevent tricuspid atresia.
Webb GD, Smallhorn JF, Therrien J, Redington AN. Congenital heart disease. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. Philadelphia, Pa: Elsevier Saunders; 2011:chap 65.
Kurt R. Schumacher, MD, Pediatric Cardiology, University of Michigan Congenital Heart Center, Ann Arbor, MI. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.