Hypoplastic Left Heart Syndrome (HLHS) in Children
Hypoplastic left heart syndrome (HLHS) is a group of defects of the heart and large
blood vessels. A child is born with this condition (congenital heart defect). It occurs
when part of the heart doesn't develop as it should during the first 8 weeks of
HLHS, most of the left side of the heart is small, underdeveloped, or both. The
following structures are usually affected:
This valve controls blood flow between the left atrium and left
This is the lower left chamber of the heart. It pumps blood to the
This valve controls blood flow from the left ventricle into the aorta,
and then to the body. The aorta is the major blood vessel that delivers blood to the
This is the large artery leading from the left ventricle to the body.
left ventricle is normally very strong, so it can pump blood to the body. When it
small and poorly developed, it can't pump any or enough blood out to the body. For
reason, a baby with HLHS will not live long without surgery to fix the defect.
child is born with this condition (congenital). Some congenital heart defects occur
often in certain families (genetic defects).
In many children, HLHS occurs by chance. There is no clear reason for its development.
Babies with hypoplastic left heart syndrome usually get symptoms shortly after
- Blue color of the skin, lips, and nails (cyanosis)
- Pale skin
- Sweaty, clammy, or cool skin
- Trouble breathing
- Fast heart rate
- Cold feet
- Poor pulses in the feet
- Poor feeding
symptoms of HLHS may look like other health conditions and heart problems. Your child
needs to see a healthcare provider for a diagnosis.
many cases, hypoplastic left heart syndrome can be diagnosed with an ultrasound while
the baby is still in the womb (uterus). After birth, you or your healthcare provider may
notice that your baby seems limp or listless, has trouble breathing, or has a blue
to their skin, lips, or nails. Your child will need a pediatric cardiologist to make
the diagnosis. This is a doctor with special training in treating heart problems
cardiologist will examine your baby, listen to their heart and lungs, and make other
observations. Testing for congenital heart disease varies. Your child may have these
Echocardiogram (echo). An echo uses sound waves to make moving pictures of
the heart and heart valves. Children with HLHS are almost always diagnosed by
Chest X-ray. A chest X-ray
may show problems that appear with HLHS.
Electrocardiogram (ECG). An ECG records the electrical activity of the
heart. It shows abnormal rhythms (arrhythmias) and finds heart muscle damage.
baby will most likely be cared for in the neonatal intensive care unit (NICU). At
they may get oxygen or be placed on a ventilator. This is to help with breathing.
child may get IV medicine. The medicine helps the heart and lungs work.
most cases, surgery is used to treat hypoplastic left heart syndrome. Your baby’s
cardiologist and cardiac surgeon will explain the risks and benefits. A heart
transplant is another option. But it can be very difficult to find a donor heart for
baby. Also, the child will need to take medicines for the rest of their life to prevent
rejection. For this reason, transplant may not be a first choice.
Surgery typically involves a series of several surgeries. In this very complex
treatment, the surgeon redirects blood flow to the lungs and the body through several
connections. The surgery is done in stages. The first surgery is done shortly after
birth. The second stage is done between ages 4 to 6 months, and the third stage is
between ages 18 months and 3 years. Another option for treatment of HLHS is a
combination of surgery and cardiac catheterization. This is called a hybrid procedure.
It accomplishes the goal of the first surgery without the need for placing your child
a heart-lung machine. This procedure is typically reserved for children who are at
risk, such as prematurity, low birth weight, and organ dysfunction.
the surgery, your baby will return to the intensive care unit (ICU) to be closely
watched. After the first surgery, you can expect your child to be in the hospital
several weeks. When your child is well enough to go home, the healthcare provider
recommend pain medicine such as acetaminophen or ibuprofen to keep your child
comfortable. Your child's healthcare provider will discuss pain control before your
Typically, after the first surgery, your baby will need frequent monitoring even when
home. This may involve frequent phone calls with the medical team, daily checks of
baby's oxygen levels, and daily weights. Many centers have specialized programs that
help families and train them in how to care for the baby at home. If any special
treatments are to be given at home, the nursing staff will make sure that you or a
health agency is able to provide them.
You may get other instructions from your child's healthcare providers and the hospital
baby with hypoplastic left heart syndrome needs surgery. to survive.
first stage of the surgery has the highest risk for complications and death. Some
special treatment centers that do many of these procedures have higher survival rates
than centers where fewer procedures are done. Survival rates are higher with the second
and third stages of surgery.
Babies and children who have the staged surgeries will need special care and treatment
to support growth and development. These children may have physical developmental
and will likely need extra support. Some children will need a heart transplant to
survive into adulthood. They will also need regular follow-up care at a center
specializing in this type of congenital heart care.
the long term, children with HLHS have an increased risk for complications such as
failure and heart rhythm problems. They are also at risk for digestive and liver
problems. Children with HLHS after surgery often have lower exercise tolerance.
Discuss your child's specific outlook with the healthcare provider.
When to Call a Healthcare Provider
Call your child's healthcare provider if your child's symptoms get worse or if new
- Hypoplastic left heart syndrome is a group of problems that affect the heart and large
- Babies usually get symptoms shortly after birth.
with HLHS need surgery to survive.
babies will need a series of surgeries during their first 2 to 3 years of life.
the surgeries, children will need special care and to be monitored for
Tips to help you get the most from a visit to your child’s healthcare provider:
- Know the reason for the visit and what you want to happen.
- Before your visit, write down questions you want answered.
- At the
visit, write down the name of a new diagnosis and any new medicines, treatments, or
tests. Also write down any new instructions your provider gives you for your
- Know why a new medicine or treatment is prescribed and how it will help your child.
Also know what the side effects are.
- Ask if your child’s condition can be treated in other ways.
- Know why a test or procedure is recommended and what the results could mean.
- Know what to expect if your child does not take the medicine or have the test or procedure.
- If your child has a follow-up appointment, write down the date, time, and purpose
for that visit.
how you can contact your child’s provider after office hours. This is important if
your child becomes ill and you have questions or need advice.