Before birth

It's possible for a baby to be diagnosed with hypoplastic left heart syndrome while still in the womb. Your doctor might be able to identify the condition on a routine ultrasound exam during the second trimester of pregnancy.

After birth

After your baby is born, a doctor might suspect a heart defect, such as hypoplastic left heart syndrome, if your baby has grayish-blue skin color or has trouble breathing. Your baby's doctor might also suspect a heart defect if he or she hears a heart murmur — an abnormal sound caused by turbulent blood flow — when listening to the heart with a stethoscope.

Doctors usually use an echocardiogram to diagnose hypoplastic left heart syndrome. This test uses sound waves that bounce off your baby's heart to produce moving images that can be viewed on a video screen.

If your baby has hypoplastic left heart syndrome, the echocardiogram will show a smaller than normal left ventricle and aorta. The echocardiogram might also show abnormal heart valves.

Because this test can track blood flow, it also shows blood moving from the right ventricle into the aorta. In addition, an echocardiogram can identify associated heart defects, such as an atrial septal defect.


Hypoplastic left heart syndrome is treated through several surgical procedures or a heart transplant. Your child's doctor will discuss treatment options with you.

If the diagnosis has been made before the baby is born, doctors usually recommend delivery at a hospital with a cardiac surgery center.

Your baby's doctor might recommend several options to help manage your baby's condition before surgery or transplant, including:

  • Medication. The medication alprostadil (Prostin VR Pediatric) helps widen the blood vessels and keeps the ductus arteriosus open.
  • Breathing assistance. If your baby has trouble breathing, he or she may need help from a breathing machine (ventilator) to get enough oxygen.
  • Intravenous fluids. Your baby will receive fluids through a tube inserted into a vein.
  • Feeding tube. If your baby has trouble feeding or tires while feeding, he or she can be fed through a feeding tube.
  • Atrial septostomy. This procedure creates or enlarges the opening between the heart's upper chambers (atria) to allow more blood flow from the right atrium to the left atrium if the foramen ovale closes or is too small. If your baby already has an atrial septal defect, an atrial septostomy might not be necessary.

Surgeries and other procedures

Your child will likely need several surgical procedures to treat hypoplastic left heart syndrome. Surgeons perform these procedures to create separate pathways to get oxygen-rich blood to the body and oxygen-poor blood to the lungs. The procedures are done in three stages.

  • Norwood procedure. This surgery is usually done within the first two weeks of your child's life. There are several ways to do this procedure.

    Surgeons reconstruct the aorta and connect it to the heart's lower right chamber (right ventricle). Surgeons insert a tube (shunt) that connects the aorta to the arteries leading to the lungs (pulmonary arteries), or they place a shunt that connects the right ventricle to the pulmonary arteries. This method allows the right ventricle to pump blood to both the lungs and the body.

    In some cases, a hybrid procedure is done. Surgeons implant a stent in the ductus arteriosus to maintain the opening between the pulmonary artery and aorta. Bands placed around the pulmonary arteries reduce blood flow to the lungs and create an opening between the atria of the heart.

    After the Norwood procedure, your baby's skin will still have a blue coloring because oxygen-rich and oxygen-poor blood continue to mix within the heart. Once your baby successfully passes through this stage of treatment, the odds of survival can increase.

  • Bidirectional Glenn procedure. This procedure is generally the second surgery. It's done when your child is between 3 and 6 months of age. Doctors remove the first shunt attached to the pulmonary arteries, and then connect one of the large veins that normally returns blood to the heart (the superior vena cava) to the pulmonary artery instead. If surgeons previously performed a hybrid procedure, they'll follow additional steps during this procedure.

    This procedure reduces the work of the right ventricle by allowing it to pump blood mainly to the aorta. It also allows most of the oxygen-poor blood returning from the body to flow directly into the lungs without a pump.

    After this procedure, all the blood returning from the upper body is sent to the lungs, so blood with more oxygen is pumped to the aorta to supply organs and tissues throughout the body.

  • Fontan procedure. This surgery is usually done when your child is between 18 months and 4 years of age. The surgeon creates a path for the oxygen-poor blood in one of the blood vessels that returns blood to the heart (the inferior vena cava) to flow directly into the pulmonary arteries. The pulmonary arteries then transport the blood into the lungs.

    The Fontan procedure allows the rest of the oxygen-poor blood returning from the body to flow to the lungs. After this procedure, there's minimal mixing of oxygen-rich and oxygen-poor blood in the heart, and your child's skin will no longer look blue.

  • Heart transplant. Another surgical option is a heart transplant. However, the availability of a heart to be used for transplant is limited, so this option is not used as often. After a heart transplant, your child will need medications throughout life to prevent rejection of the donor heart.

Follow-up care

After surgery or a transplant, your baby will need lifelong follow-up care with a cardiologist trained in congenital heart diseases. Some medications might be needed to regulate heart function. Various complications can occur over time and might require further treatment or other medications.

Your child's cardiologist will tell you whether your child needs to take preventive antibiotics before certain dental or other procedures to prevent infections. In some cases, the doctor might also recommend that your child limit physical activity.

Follow-up care for adults

As an adult, you'll transition from a pediatric cardiologist to a cardiologist trained in congenital heart disease in adults. Only recently have advances in surgical care resulted in children with hypoplastic left heart syndrome surviving into adulthood, so it's not yet clear the challenges an adult with the condition might face. You'll need regular, lifelong follow-up care to monitor for any changes in your condition.

Women considering pregnancy should discuss pregnancy risks and birth control options with their doctors. Having this condition increases your risk of cardiovascular problems during pregnancy, the risk of miscarriage and the risk of having a baby with congenital heart disease.

Clinical trials

Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this condition.

Coping and support

It can be challenging to live with hypoplastic left heart syndrome or to care for a baby with the condition. Here are some strategies that may help make it easier:

  • Seek support. If you have a child with hypoplastic left heart syndrome, ask family members and friends for help. It's important for caregivers to take breaks. Talk with your child's cardiologist about support groups and other types of assistance.

    If you're a teen or an adult with hypoplastic left heart syndrome, ask your doctor if there are support groups for adults with congenital heart conditions. It can be helpful to talk to other people who share your challenges.

  • Record your or your baby's health history. Write down your or your baby's diagnosis, medications, surgery and other procedures and the dates they were performed, as well as the name and phone number of your or your child's cardiologist, emergency contact numbers for your or your child's doctors and hospital, and other important information about your or your baby's care. Include a copy of the operative report from your or your child's surgeon in your records.

    This information will help you recall the care you or your child has received, and it will be useful for doctors who are unfamiliar with you or your baby to review the complex health history. This information is also helpful as your child grows into adulthood and transitions from pediatric to adult cardiology care.

  • Talk about your concerns. As your child grows, talk with the cardiologist about which activities are best for your child. If some are off-limits, encourage your child in other pursuits rather than focusing on what he or she can't do.

    If other issues about your child's health concern you, discuss them with your child's cardiologist, too. As an adult, ask your doctor about what activities you can do, and about your concerns.

Hypoplastic left heart syndrome care at Mayo Clinic

Dec. 03, 2020
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