Small vessel avulsion and acute aortic syndrome: A putative aetiology for initiation and propagation of blunt traumatic aortic injury at the isthmus

SummaryBased on literature, clinical observation and the analysis of material properties of the aorta, we hypothesize that the aortic isthmus is intrinsically susceptible to blunt trauma because it has a higher density of tributary vessels than other elements of the aortic tree, the avulsion of which during trauma, is a contributory factor in the development of an acute aortic syndrome resulting from intra-mural haematoma, localized dissection and ultimately rupture. This hypothesis provides putative explanations for several aspects of the injury profile including: localized peri-isthmus injuries, inside out injury profiles and the concept of initiation versus propagation of blunt traumatic aortic injury.