Hypoplastic Right Ventricle or Tricuspid Atresia

Similar to hypoplastic left heart syndrome, a baby born with hypoplastic right ventricle or tricuspid atresia may immediately experience severe symptoms and need medical intervention quickly. In both congenital heart diseases, the ventricle (bottom chamber) is underdeveloped or nonexistent. The other side of the pumps harder to compensate but the extra stress can cause other health problems, including congestive heart failure. The tricuspid valve between the right atrium (upper chamber) and ventricle is also missing or blocked off with tricuspid atresia. After treatment, children with hypoplastic right ventricle can have active lives.

Wellness & Prevention

During the first eight weeks of pregnancy, the baby’s heart develops from a hollow tube into four chambers. Tricuspid atresia happens when the tricuspid valve doesn’t form properly in those weeks. Because the ventricles need blood flowing through to fully develop, a faulty tricuspid valve blocks the flow of blood and the right ventricle can’t grow to a normal size. In a hypoplastic right ventricle heart, oxygen-poor blood returns from body through the right atrium but it can’t flow into the right ventricle to be pumped to the lungs for oxygenation.

Children who have hypoplastic right ventricle can also have related conditions. Most have pulmonary stenosis, or a narrowing of the pulmonary valve and pulmonary artery, and ventricular septal defect that leaves a hole in the wall between the ventricles and allows blood to mix. For some children with tricuspid atresia, the pulmonary artery and aorta can also be attached to the wrong ventricle in an associated defect called transposition of the great arteries or transposition of the great vessels.

Two natural holes in the heart that typically close after birth can help your baby’s heart compensate for hypoplastic right ventricle. The ductus arteriosus blood vessel connects the pulmonary artery and the aorta and lets oxygenated and oxygen-depleted blood mix, allowing some blood to reach the lungs for oxygen.

The ductus arteriosus usually closes shortly after birth but a pediatric cardiologist can prescribe medication to keep the hole open until a baby with tricuspid atresia can have surgery. If the ductus arteriosus closes, the baby may not receive enough oxygen and her life could be threatened.

The second opening, called the foramen ovale, is in the wall between the atria. The foramen ovale lets oxygen-poor blood in the right atrium mix with oxygen-rich blood in the left atrium. The mixed blood can move into the left ventricle and be pumped to the body through the aorta. Because the mixed blood doesn’t contain enough oxygen, the baby’s skin, lips and nails may begin to look blue though.

A baby born with hypoplastic right ventricle tends to have severe symptoms shortly after birth. Symptoms vary but may include:

  • Fatigue and weakness
  • Poor weight gain and growth
  • Labored or rapid breathing
  • Blue-colored skin
  • Circulatory collapse
  • Rapid heartbeat
  • Swelling

Diagnosis

You child’s doctor may first suspect hypoplastic right ventricle if your baby has cyanosis, a blue tint to the skin caused by inadequate oxygen in the blood, or she may hear a heart murmur during a physical examination. To confirm a diagnosis of tricuspid atresia, a pediatric cardiologist may perform different tests including:

  • Chest X-ray: An X-ray gives a pediatric cardiologist an image of the tissue, bones and organs in your child’s chest. An X-ray shows the size and shape of your baby’s heart and the lungs too.
  • Electrocardiogram (ECG or EKG): Electrocardiograms measure and record the activity in the heart’s electrical conduction system through electrodes placed on your baby’s chest, arms and legs. An ECG shows cardiac arrhythmias and stress on the heart muscle.
  • Echocardiogram: Using sound waves, an echocardiogram creates a moving image of the heart and valves. The test also assesses the structure and function of the heart, including how blood flows and how well the heart pumps.
  • Cardiac catheterization: A tiny catheter is inserted through a larger blood vessel, often in the groin, and guided to the heart to take blood pressure and oxygen measurements.

Treatments

Treatment may start soon after birth with IV medications to keep the ductus arteriosus open. Your pediatric cardiologist may also prescribe medication to help dilate blood vessels. Another early treatment may involve using cardiac catheterization and a balloon to create or widen the foramen ovale and let more oxygenated blood reach the body.

A child with tricuspid atresia will likely need a series of surgeries in the first two years to restore adequate function to the heart.

Aftercare

A child with tricuspid atresia may need lifelong care from a cardiologist to monitor his heart health and make adjustments to medications or treatments. Babies may need surgery as they grow older to continue improving function.

Some children who have hypoplastic right ventricle can be active with no restrictions. Others may need to restrict their activities depending on their pediatric cardiologist’s recommendation.