Hypoplastic Left Heart Syndrome (HLHS)

What are hypoplastic left heart syndrome symptoms?

Children with hypoplastic left heart syndrome develop a blue or gray tint to their skin. This condition is called cyanosis. The blue color can become more intense when an infant cries.

Other hypoplastic left heart syndrome symptoms to look for include:

• Low or faint pulse
• Trouble nursing and feeding
• Fast breath or shortness of breath
• Extreme tiredness
• Loud heartbeat

How is hypoplastic left heart syndrome diagnosed?

In some cases, a child's HLHS will be diagnosed during a routine ultrasound exam before he or she is born. If your doctor suspects hypoplastic left heart syndrome, more tests will be needed to confirm the syndrome.

The most common test is an echocardiogram that lets pediatric cardiologists see the structure of the heart and how it is functioning.

Other cardiac tests include:

• Chest X-ray
• EKG
• Cardiac catheterization
• Intracranial and renal ultrasounds

What are hypoplastic left heart syndrome treatment options?

At Children's Colorado's Heart Institute, our doctors are experts at identifying and treating HLHS.

Hypoplastic left heart syndrome treatment options include:

Medication

After your child is diagnosed, your pediatric heart cardiologist will start him or her on medicine that helps keep the natural passage (ductus arteriosus) between the aorta and pulmonary artery open. This medicine is called PGE-2. It allows oxygen-rich blood and blood that needs oxygen to mix inside a child's heart.

Surgery

There are two options for surgery for children with hypoplastic left heart syndrome: a surgical repair or a heart transplant.

Surgical repair

HLHS repair takes a series of surgeries, usually three, that typically take place within the first four years of a child’s life.

The first surgery, called the Norwood procedure, is performed in the first week of life. This surgery allows the right ventricle to function as the pumping chamber to get blood to both the lungs and the body.

During the Norwood procedure, the pulmonary artery and aorta are combined to create one larger path for blood to get from the heart to the body. The heart wall between the left and right atria is removed to let oxygen-rich and oxygen-poor blood mix in the heart. An artificial tube is made between the heart and the lungs so blood can get to the lungs.

The second surgery, the Glenn procedure (sometimes called a bi-directional Glenn or the Hemi-Fontan), is usually performed between 4 and 6 months of age. This surgery redirects blood from the upper part of the body away from the heart and directly to the lungs.

The final surgery redirects the blood from the lower part of the body away from the heart directly to the lungs. This is called the Fontan procedure and is usually performed at 2-4 years of age.

Following this series of surgeries, most children can have normal lives. But like any child with a complex congenital heart abnormality, he or she will need to see a pediatric cardiologist for monitoring after the repairs.

Heart transplant

The second option for kids with hypoplastic left syndrome is a heart transplant. At Children's Colorado, we have been transplanting hearts for more than 20 years.

Rather than doing surgery to repair the existing heart, a heart transplant will replace the defective heart with a new one from a donor. Transplant patients will require lifelong medication and will be followed by a transplant cardiologist to monitor possible rejection of the new organ.

Learn more about our nationally ranked Heart Transplant Program.

Living with hypoplastic left heart syndrome

Children with hypoplastic left heart syndrome will need regular follow-up appointments with a pediatric cardiologist to monitor their health. Most children will need to take medication after surgery.

If you'd like to learn more about hypoplastic left heart syndrome, visit:

• The U.S. Library of Medicine
• The American Heart Association
• HLHS information page run by parents of children with hypoplastic left heart syndrome