Anne Shu-Lei Chin MD, Presenter: Nothing to Disclose

Patients with prior aortic dissection remain at risk for repeat events, particularly those with hereditary aortopathy. CT angiographic (CTA) findings of acute aortic lesions superimposed on prior chronic dissection may be difficult to interpret. Our aim is to evaluate the incidence of aortic re-dissection in the clinical setting of acute aortic syndrome (AAS), and describe CTA imaging characteristics and clinical outcomes.

CTAs from Jan 1, 2003 - Dec 31, 2012 in 497 patients presenting to a single instituion with AAS were retrospectively reviewed by two cardiovascular radiologists. Aortic re-dissection was defined as an acute aortic lesion occurring in the same aortic segment affected by a prior aortic dissection, greater than 30 days after the inital aortic event. Patients with age-indeterminant lesions were excluded. 

A total of 513 AAS occurred over the 10-year study period. The incidence of aortic re-dissection was 2.3% (12/513). The time interval between the historic event and the acute re-dissection ranged from 38-1777 days. The mean age of patients with re-dissection was 55.2 years (range 43-68 years); a third had a history of Marfan's syndrome. There were 7 new classic aortic dissection (AD) and 5 intramural hematoma (IMH) re-dissections. There were 2 type A and 10 type B lesions. One re-dissection was complicated by aortic rupture. AD re-dissections had the unique CTA characteristic of 2 intimal-medial flaps and 3 flow lumens, typically involving the original false lumen. IMH re-dissections had acute extensive intramural hemorrhage within the false lumen of prior chronic AD. Both type A and 4/10 type B lesions underwent surgical repair.

Aortic re-dissection within a chronic dissection is rare, but can present with AAS indistinguishable from the first event. CTA imaging characteristics are unique given persistent findings of the initial dissection, but can confirm the presence of a new acute aortic lesion. The false lumen of re-dissections often expands quickly, and urgent treatment is required. While the true incidence of rupture and death from re-dissection remains unknown, these lesions tend to be unstable requiring surgical repair

Aortic re-dissection is rare but can present as an acute aortic syndrome. CTA can confirm the presence of a new acute aortic lesion in the same aortic segment, despite persistence of the prior chronic dissection.

Chin, A, Incidence and CT Angiographic Characteristics of Aortic Re-Dissection: A 10-Year Single Center Experience.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14018749.html