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