Background: Blunt aortic injury (BAI) in young patients with a compliant aorta and evolving hyperdynamic physiology may result in significant variation in aortic diameter during the cardiac cycle. Intravascular ultrasound (IVUS) may be useful to detect real-time variations in aortic diameters for more reliable sizing in patients undergoing thoracic endovascular aortic repair (TEVAR) of BAI.
Methods: This is a single-institution retrospective study of patients who underwent TEVAR for BAI in a Level 1 trauma center from January 2004 to January 2014. Patients underwent either trauma survey computed tomography (CT) alone (CT group) or IVUS and CT (IVUS group). We compared predeployment aortic measurements, implanted device size, landing zones, and repair outcomes between the groups.
Results: Forty-one patients underwent TEVAR for BAI: 28 were in the CT group and 13 in the IVUS group. Left subclavian artery (LSCA) coverage was performed in 50% (CT group) and 38% (IVUS group) of patients. CT-based median aortic diameter was similar in both groups (20.5 mm in the CT group vs. 19.0 mm in the IVUS group, p = 0.374). The median proximal diameter of the proximal device implanted was 26 mm in the CT group and 24 mm in the IVUS group (p = 0.329), which resulted in oversizing of 25.7% and 13.7% (p < 0.001), respectively. The implanted device was changed in 6 of 13 patients and in 4 of 5 patients in which the LSCA was covered because of IVUS measured-diameters. Graft extension proximal to the LSCA resulted in greater differences between the CT and IVUS measurements of the proximal aorta than if the graft was isolated to the descending aorta (18.8% vs. 5.57%, p = 0.005). Technical success of repair for both groups was 100%; no secondary interventions were required in either group.
Conclusion: In combination with CT, IVUS provides important separate sizing information at the point of implantation for more accurate device selection, eliminating need for a repeat CT.
Level of evidence: Therapeutic study, level IV.