Hypoplastic Left Heart Syndrome
Hypoplastic left heart syndrome (HLHS) is a birth defect that affects normal blood flow through the heart. As the baby develops during pregnancy, the left side of the heart does not form correctly. Hypoplastic left heart syndrome is one type of congenital heart defect. Congenital means present at birth.
Hypoplastic left heart syndrome affects a number of structures on the left side of the heart that do not fully develop, for example:
In babies with hypoplastic left heart syndrome, the left side of the heart cannot pump oxygen-rich blood to the body properly. During the first few days of life for a baby with hypoplastic left heart syndrome, the oxygen-rich blood bypasses the poorly functioning left side of the heart through the patent ductus arteriosus and the patent foramen ovale. The right side of the heart then pumps blood to both the lungs and the rest of the body. However, among babies with hypoplastic left heart syndrome, when these openings close, it becomes hard for oxygen-rich blood to get to the rest of the body.
The Centers for Disease Control and Prevention (CDC) estimates that each year about 960 babies in the United States are born with hypoplastic left heart syndrome. In other words, about 1 out of every 4,344 babies born in the United States each year is born with hypoplastic left heart syndrome.
The facts above are for Hypoplastic Left Heart Syndrome, a severe CHD. For more generalized facts about congenital heart defects, please click HERE.
This information is taken directly from the Center of Disease Control.
Hypoplastic left heart syndrome affects a number of structures on the left side of the heart that do not fully develop, for example:
- The left ventricle is underdeveloped and too small.
- The mitral valve is not formed or is very small.
- The aortic valve is not formed or is very small.
- The ascending portion of the aorta is underdeveloped or is too small.
- Often, babies with hypoplastic left heart syndrome also have an atrial septal defect, which is a hole between the left and right upper chambers (atria) of the heart.
In babies with hypoplastic left heart syndrome, the left side of the heart cannot pump oxygen-rich blood to the body properly. During the first few days of life for a baby with hypoplastic left heart syndrome, the oxygen-rich blood bypasses the poorly functioning left side of the heart through the patent ductus arteriosus and the patent foramen ovale. The right side of the heart then pumps blood to both the lungs and the rest of the body. However, among babies with hypoplastic left heart syndrome, when these openings close, it becomes hard for oxygen-rich blood to get to the rest of the body.
The Centers for Disease Control and Prevention (CDC) estimates that each year about 960 babies in the United States are born with hypoplastic left heart syndrome. In other words, about 1 out of every 4,344 babies born in the United States each year is born with hypoplastic left heart syndrome.
The facts above are for Hypoplastic Left Heart Syndrome, a severe CHD. For more generalized facts about congenital heart defects, please click HERE.
This information is taken directly from the Center of Disease Control.
Factual information provided by the American Heart Association and The Children's Heart Foundation and the Center for Disease Control. We are not doctors and do not give medical advice. This site is for informational purposes.