Coarctation of Aorta

  • Infantile / diffuse = preductal from innominate artery to ductus arteriosus
    Etiology: congenital
    Imaging: long segment narrowing
    Clinical: left sided obstructive lesion, neonatal ductal dependent for collateral flow
  • Adult / focal = ductal / postductal
    Etiology: acquired, due to rubella or neurofibromatosis type 1 in adults
    CXR: 3 sign is prestenotic dilation of ascending aorta / coarctation / post-stenotic dilation of descending aorta, rib notching takes 10 years due to shunting from subclavian artery -> internal thoracic artery -> intercostal arteries -> descending aorta, first 2 ribs spared from notching because they are supplied from costocervical trunk
    UGI: Reverse 3 sign is hypoplastic aortic knob with dilated post stenotic segment
    Clinical: most common form, presents later due to presence of collaterals

Cases of Coarctation of Aorta

CXR of coarctation of aorta
CXR AP shows a 3 sign in the region of the aortic arch and bilateral rib notching.