Hypoplastic left heart syndrome (HLHS) is a severe congenital heart defect characterized by a small (underdeveloped) and functionally inadequate left ventricle. In a normal heart, the left side pumps oxygenated blood to the aorta, which then carries the blood to the body. In a baby with HLHS, the mitral valve and aortic valve are too small (atretic) or completely closed and nonfunctioning. As a result, the blood flow to the body is severely restricted.
Initially, a baby may present with little-to-no symptoms due to the presence of the PDA. However, when the PDA closes, this could be very serious and life threatening for the infant. The following are some symptoms associated with HLHS:
Blue or purple lips, skin and nails
Cool extremities
Difficulty breathing/increased work of breathing
Difficulty feeding
Diaphoresis/clammy skin
Lethargy (excessive sleepiness)
Low oxygen saturation reading on the CR monitor
Diagnosis may require some or all of the following tests:
Echocardiogram
Electrocardiogram
Cardiac catheterization
Cardiac MRI
HLHS is often fatal without early intervention and immediate treatment. Medications may help stabilize the baby initially, but surgery will be absolutely necessary and vital for survival. Open-heart surgery is performed in order to redirect the oxygen-rich and oxygen-poor blood. The end result is that the right side will take over the role of the left and pump oxygenated blood to the body. The deoxygenated blood will flow from the veins to the lungs without passing through the heart.
A series of three reconstructive operations will be performed to repair the heart; these include the Sano Modification of the Norwood Procedure (immediately after birth), Glenn repair (around 6 months of age), and Fontan (3-4 years old). These three stages are referred to as “Staged Reconstruction.”
After the baby is discharged, pediatric cardiologists will continue to follow him/her well into young adulthood, coordinating care as needed.
