Hypoplastic Left Heart Syndrome (HLHS) | Symptoms and Causes

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What are the symptoms of hypoplastic left heart syndrome?

At first, a newborn with hypoplastic left heart syndrome (HLHS) may appear normal, but symptoms usually develop in the first few hours or days of life. Lack of vital blood flow causes the baby to go into profound shock, endangering the brain, liver, kidneys and other vital organs.

  • rapid breathing or shortness of breath
  • rapid heartbeat or pounding heart
  • poor suckling and feeding
  • cold extremities (poor perfusion)
  • blue color of the skin, lips and nailbeds (cyanosis)
  • lethargy

What causes hypoplastic left heart syndrome?

It’s important to understand that as parents, you’ve done nothing to cause HLHS and its associated defects. HLHS is the result of under development of sections of the fetal heart during the first eight weeks of pregnancy. But it’s not understood why some babies’ hearts don’t develop normally. Congenital heart defects usually occur sporadically (by chance) with no clear reason for their development.

When to seek medical advice

Call your health care provider immediately if your child is having difficulty breathing or is breathing rapidly, has a bluish color, tires easily, has cold hands and feet, is drowsy or unresponsive, and is uninterested in eating.

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