PHACE Syndrome (hemangiomas)

PHACE_syndromeThere are no shortage of congenital syndromes that are acronyms arranged into some sort of vaguely pronounceable word. There will be lots of doodles about these, but we’ll start off with a more uncommon one – PHACE Syndrome.

PHACE Syndrome is a collection of findings that go along with large infantile hemangiomas. They’re the more worrisome (but less obviously disfiguring) things you need to look for when you see a baby with a large hemangioma on the face or multiple hemangiomas.

  • Posterior fossa brain malformations
  • Hemangiomas
  • Arterial anomalies
  • Cardiac anomalies and coarctation of the aorta
  • Eye abnormalities
  • Sternal cleft

The most common symptom of PHACE is cerebrovascular abnormalities, followed by cardiac anomalies (coarctation, aortic arch anomalies, VSDs). If you suspect PHACE, do clinical exam of the skin and eyes and MRI of the head, neck and chest.

Other cool facts

  • PHACE occurs in full-term normal birth weight infants (other hemangiomas tend to occur in preterm infants)
  • Quite common, more girls than boys (8:1)
  • Don’t confuse it with Strurge-Weber (port wine stain, associated with the facial dermatomes)
    • Port wine stains don’t proliferate and then regress like an infantile hemangioma

Acyanotic vs Cyanotic Congenital Heart Defects

You separate congenital heart defects into acyanotic and cyanotic. Basically, is the baby (or kid) nice and pink, or is he or she dusky as they like to say. Sometimes the blueishness only happens when they’re working really hard, like feeding and crying (or thinking about the pathophysiological mechanisms of heart disease).

One of the important things to remember is that acyanotic heart defects can switch over if they’re left alone for too long because of pulmonary hypertension caused by the extra flow. This is called Eisenmenger Syndrome.

It’s also important to realize that many of the cyanotic lesions are duct dependent, meaning that as long as the ductus arteriosus is open, they are happy and pink. The problems start in that time 6-24h after delivery when the ductus closes. Thankfully you can keep it open by giving prostaglandin E1.

Need the ductus for systemic circulation:

  • Coarctation of the aorta
  • Critical aortic stenosis
  • Hypoplastic left heart syndrome

Need the ductus for pulmonary circulation:

  • Pulmonary atresia
  • Critical pulmonary stenosis
  • Tricuspid atresia
  • Tetralogy of fallot

Also, I realize that the 5 Ts of cyanotic heart lesions are a pentad of 6 (plus some), but mnemonics can only do so much, and the T thing is just so catchy.

For a more detailed illustration of PDAs, you can check out this doodle!

Patent ductus arteriosus

Normal fetal circulation

The ductus arteriosus is a connection between the aorta and pulmonary artery present in the fetal circulation. Since the pulmonary vascular pressure is higher than the systemic pressure, blood is shunted through the ductus from the right to the left, bypassing the lungs.

 

When the baby is born, the resistance in the pulmonary vascular falls and more of the blood goes through the lungs. In conjunction with this the fall in the level of circulating prostaglandins causes the contraction of the ductus arteriosus.

Patent ductus arteriosus

In some babies, particularly those born prematurely, the ductus fails to close and the shunt becomes left to right.

This gives you the classic “continuous machine-like murmur