IS Case 232: Descending thoracic aortic pseudoaneurysm

Jeremy Sykes, MD

Imaging Sciences URMC 2008
Publication Date: 2009-05-22

History

Patient is a 4-month-old male with one day history of upper respiratory symptoms and difficulty feeding.

Findings

A portable AP chest radiograph demonstrates a large left-sided chest mass projecting posterior to the heart and extending from the area of the aortic knob to the left hemidiaphragm. Contrast-enhanced CT images of the chest demonstrate pseudoaneurysmal dilatation of the thoracic aorta with a large false lumen anteromedial to a smaller true lumen, with a large amount of thrombus along the wall of the false lumen. The thoracic aorta is tortuous as it courses below the left hemidiaphragm to continue as a normal abdominal aorta.

Diagnosis

Descending thoracic aortic pseudoaneurysm

Discussion

Aortic aneurysms of any kind are exceedingly rare in the pediatric population, but occur most often in the descending aorta. Arterial aneurysms in infancy are classified as follows: arterial infection (secondary to Staphylococcus aureus and Salmonella), giant cell aortoarteritis/autoimmune vasculitis (Kawasaki disease), degeneration of the media layer (Ehlers-Danlos and Marfan syndromes), disruption of the arterial layers (pseudoaneurysm), or idiopathic/congenital (congenital defect in type III collagen). Aortic pseudoaneurysms have also been described secondary to trauma.

In the above case, imaging suggested and surgical repair proved that the patient had a pseudoaneurysm of the descending thoracic aorta. While the exact etiology has not been confirmed, genetic testing was begun for the suspicion of Loeys-Dietz syndrome, which is a Marfan-like syndrome first described in 2005 where there is mutation of the TGF-beta 1 or 2 receptors. Among the many possible features of this syndrome, three main features that this patient demonstrates include aortic tortuosity with or without aneurysm or dissection, a bifid uvula, and contractures of the fingers/toes.

The pseudoaneurysm was successfully resected and repaired with an end-to-end anastomosis.

References

  1. Marín-Manzano E, González-de-Olano D, Haurie-Girelli J, et al. Idiopathic thoracic aortic aneurysm at pediatric age. Ann Vasc Surg. 2008 Sep 20:1-3. [PMID: 18809285]
  2. Bichell DP, Saenz NC, LoSasso BE, Sobo EJ. Pediatric aortic pseudoaneurysm associated with a gunshot wound to the chest. J Trauma. 2000 Apr;48(4):791. [PMID: 10780623]
  3. Loeys BL, Chen J, Neptune ER, et al. A syndrome of altered cardiovascular, craniofacial, neurocognitive and skeletal development caused by mutations in TGFBR1 or TGFBR2. Nat Genet. 2005 Mar;37(3):275-81. [PMID: 15731757]

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