Aortic Isthmus Narrowing after Endovascular Repair of Acute Traumatic Aortic Transection.

Purpose: The traumatic transection is located in the normal sized aortic isthmus where the angle is curved. We found a reversal of upper and lower blood pressure differences among patients who underwent thoracic endovascular aortic repair (TEVAR) for transection of the thoracic aorta. We investigated the isthmus stenosis in patients who underwent TEVAR for aortic injury using computed tomography.

Materials and Methods: Sixteen patients who underwent TEVAR for transection were divided in two groups: the aortic narrowing (AN) group and the non-aortic narrowing (NAN) group. AN was defined as stent graft folding more than 5 mm at the isthmus confirmed by computed tomography. The length of aorta at isthmus, pseudoaneurysm, and angle of isthmus were measured.

Results: AN was noted in five patients (31.3%). The area index in the NAN group (2.16±0.35 cm2 /m2 ) was larger than that in the AN group (1.74±0.77 cm2 /m2 ). The size of the pseudoaneurysm in the NAN group (31.9±4.2 mm) was smaller than that in the AN group (37.4±7.5 mm). The distance from the subclavian artery in the NAN group (15.7±9.3 mm) was longer than that in the AN group (8.4±3.2 mm) but not statistically significant. The angle of the isthmus in the NAN group (131±6 degrees) was larger than that in the AN group (107±3 degrees), and this was the only statistically significant difference (P=0.002).

Conclusion: AN by stent graft folding should be considered when performing TE-VAR in aortic injury with an acute angle of the isthmus less than 110 degrees.