Tetralogy of Fallot symptoms vary, depending on the extent of obstruction of blood flow out of the right ventricle and into the lungs. Signs and symptoms may include:

  • A bluish coloration of the skin caused by blood low in oxygen (cyanosis)
  • Shortness of breath and rapid breathing, especially during feeding
  • Loss of consciousness (fainting)
  • Clubbing of fingers and toes — an abnormal, rounded shape of the nail bed
  • Poor weight gain
  • Tiring easily during play
  • Irritability
  • Prolonged crying
  • A heart murmur

Tet spells

Sometimes, babies with tetralogy of Fallot will suddenly develop deep blue skin, nails and lips after crying, feeding, having a bowel movement, or kicking his or her legs upon awakening. These episodes are called Tet spells and are caused by a rapid drop in the amount of oxygen in the blood. Toddlers or older children may instinctively squat when they are short of breath. Squatting increases blood flow to the lungs. Tet spells are more common in young infants, around 2 to 4 months old.

When to see a doctor

Seek medical help if you notice that your baby has the following symptoms:

  • Difficulty breathing
  • Bluish discoloration of the skin
  • Passing out or seizures
  • Weakness
  • Unusual irritability

If your baby becomes blue (cyanotic), immediately place your child on his or her side and pull the knees up to the chest. This helps increase blood flow to the lungs. Call 911 or your local emergency number immediately.

Feb. 23, 2012

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