Hypoplastic Left Heart Syndrome (HLHS)
What is HLHS?
Hypoplastic left heart syndrome (HLHS) is a severe congenital heart defect in which the left side of the heart is underdeveloped or too small.
This means the left ventricle, the aorta and the aortic and mitral valves are too small, and because of that, the left side of the heart cannot pump oxygen-rich blood to the body properly.
HLHS is amongst the most severe forms of heart defect. Most babies are very ill in the early days of life and will need urgent surgery to survive.
Symptoms of HLHS:
Babies born with HLHS are usually very sick soon after birth. Symptoms include:
- Blue or gray skin, lips or fingernails. Depending on skin color, these changes may be harder or easier to see.
- Rapid, difficult breathing.
- Poor feeding.
- Cold hands and feet.
- Weak pulse.
- Being more drowsy or less active than is typical for most babies.
What treatment options are there?
Soon after a baby with HLHS is born, multiple surgeries done in a particular order are needed. These surgeries will help increase blood flow to the body and bypass the poorly functioning left side of the heart. The surgeries help the right ventricle become the main pumping chamber for blood to reach the body.
These surgeries do not cure HLHS but help restore heart function. Sometimes medicines are given to help treat symptoms of the defect before or after surgery. Surgery for HLHS usually is done in three separate stages:
Norwood Procedure: Usually performed during the first two weeks of life, the Norwood procedure involves reconstruction parts of the heart and placing a tube or shunt to help the right ventricle pump blood to the body and lungs. This procedure is done in the first few weeks of life, to prevent damage to the heart and lungs until the second procedure is performed.
Bi-Directional Glenn Shunt procedure: Usually performed when the child is 4-6 months of age, this procedure replaces the old shunt with a new one that allows blood to flow straight to the lungs, lowering the strain on the right side of the heart.
Fontan procedure: Usually performed when the child is aged between 18 months and 4 years, the Fontan procedure sees that the inferior vena cava is connected to the pulmonary artery. This allows all blood that needs oxygen to flow directly to the lungs.
