Partial Anomalous Pulmonary Venous Return

• Etiology: Congenital
  — Most common form is anomalous drainage of right superior pulmonary vein into superior vena cava which is often associated with superior sinus venosus atrial septal defect
  — One form is Scimitar syndrome which is right sided with pulmonary veins (forming scimitar vein) draining typically to inferior vena cava or inferior vena cava-right atrium junction with hypoplasia of right lung and right pulmonary artery
• Imaging: Findings that constitute Scimitar syndrome:
  — Right lung hypoplasia
  — Right pulmonary artery hypoplasia
  — Right lung bronchial and lobation anomalies
  — Horseshoe or crossover lung and diaphragm abnormalities
  — Aberrant systemic arterial supply with or without sequestration
  — Note: In 66% Scimitar vein drains entire right lung and in 33% Scimitar vein drains only part of right lung (usually right upper lobe)
  — Note: 20% of Scimitar veins are obstructed
• DDX:
• Complications:
• Treatment:
• Clinical: Causes left to right shunt

Radiology Cases of Partial Anomalous Pulmonary Venous Return