Pediatric Atrioventricular Canal Defect

  • Etiology: Spectrum of ostium primum atrial septal defect, cleft mitral leaflet, inlet ventricular septal defect, common atrioventricular valve, complete endocardial cushion defect
  • Imaging: Intracardiac left to right shunt leads to acyanosis and increased pulmonary blood flow
  • Imaging CXR: Shunt vascularity and cardiomegaly
  • Imaging Angiogram: Gooseneck deformity = elongation of left ventricular outflow tract
  • DDX:
  • Complications:
  • Treatment:
  • Clinical: 30% of atrioventricular canal defect seen in Down syndrome and 30% of Down syndrome have atrioventricular canal defect

Radiology Cases of Atrioventricular Canal Defect

CXR of AV canal / endocardial cushion defect
CXR AP and lateral shows hyperexpanded lungs, increased pulmonary vascularity and marked cardiomegaly.

CXR of pediatric AV canal
CXR AP shows enlargement of the heart and markedly increased pulmonary vascularity. The lungs are clear.