Pulmonary arterial aneurysm

Pulmonary arterial aneurysms refer to a focal dilatation of the pulmonary arterial system.

Overall it is considered a rare entity with autopsy prevalence rates of around 1 in 14,000 to 100,000 4,5.

A true pulmonary artery aneurysm results from dilatation of all three layers of the vessel wall while a pulmonary artery pseudoaneurysm does not involve all layers of the arterial wall. Most of the aneurysms are central, affecting the main pulmonary arteries 4.

The differential for etiologies of pulmonary artery aneurysms can be broad. Different sources differ as to the most frequent etiologies, likely due to the rarity of the entity and reliance on limited case series.

Radiographic features are non-specific and they may appear as hilar enlargement or a lung nodule.

CT angiography (CTA) allows a much better appreciation of the anatomy. Some consider enlargement or ectasia of the pulmonary trunk on CT scan to be 29 mm and the right interlobar artery to be 17 mm 1. Proximal pulmonary artery aneurysms are defined by pulmonary trunk diameter >4 cm 9.

Share article

Article information

rID: 25912
System: Vascular, Chest
Synonyms or Alternate Spellings:
  • Pulmonary arterial aneurysms
  • Aneurysm of pulmonary artery
  • Focal dilatation of the pulmonary arteries
  • Focal dilatation of the pulmonary artery
  • Pulmonary artery aneurysm
  • Pulmonary artery aneurysms

Support Radiopaedia and see fewer ads

Cases and figures

  • Case 1: with Behçet disease
    Drag here to reorder.
  • Case 2: with Behçet disease
    Drag here to reorder.
  • Case 3: infective aneurysm
    Drag here to reorder.
  • Case 4
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.