Classification Scheme Developed for Blunt Aortic Injury Treatment

November 30, 2011—The Society for Vascular Surgery (SVS) announced that investigators at the University of Washington's Harborview Medical Center in Seattle developed a classification scheme for the treatment of blunt aortic injury (BAI). Benjamin W. Starnes, MD, et al published their findings online ahead of print in the Journal of Vascular Surgery.

According to SVS, the investigators used radiographic and clinical data from 140 patients with BAI in an effort to provide clear treatment guidelines. Patient data were collected from 1999 to 2008 and studied retrospectively. Patients with radiographically or operatively confirmed BAI by echocardiography, computed tomography (CT), or angiography were included. 


“Most of the injuries were pseudoaneurysms at the isthmus (70%),” stated Dr. Starnes. “Our classification system was based on the presence or absence of an aortic external contour abnormality defined as an alteration in the symmetric round shape of the aorta.”

Injury characteristics included: (1) intimal tear (absence of an aortic external contour abnormality and intimal defect and/or thrombus < 10 mm in length or width) (16.4%); (2) large intimal flap (absence of aortic external contour abnormality and intimal defect and/or thrombus > 10 mm in length or width) (5.7%); (3) pseudoaneurysm (presence of aortic external contour abnormality and contained rupture) (71%); and (4) rupture (presence of aortic external contour abnormality and free contrast extravasation or hemothorax at thoracotomy) (6.4%).

The investigators reported survival rates by classification: intimal tear (87%), large intimal flap (100%), pseudoaneurysm (76%), and rupture (11%; one patient). Of the intimal tears, large intimal flaps, and pseudoaneurysms that were treated nonoperatively, 65% completely healed, none worsened, and no patients died. Most patients with ruptures lost vital signs before presentation or in the emergency department and did not survive. Hypotension before or at hospital presentation and the size of the periaortic hematoma at the level of the aortic arch predicted the likelihood of death from BAI.

Dr. Starnes stated, “Our classification scheme showed that no patient with a normal external contour of the aorta died of BAI, and intimal tear can be managed nonoperatively. Patients with ruptures will die, and resources may be prioritized elsewhere. Patients with large intimal flaps do well; most are treated with a stent graft.”

Dr. Starnes noted that if a pseudoaneurysm is going to rupture, it does so early, before or while in the operating room, and that the current practice at the University of Washington is to treat all pseudoaneurysms with endovascular aneurysm repair (EVAR) if the patient has a reasonable likelihood of survival. Hematoma at the arch on CT scan and hypotension before or at arrival in the emergency department also will help to predict which pseudoaneurysms need urgent instead of semielective repair. The investigators concluded that longer-term follow-up of these BAI patients is needed to determine the durability of an “endovascular first” strategy.

SVS outlined the University of Washington's recommended clinical treatment guidelines for the management of BAI as follows:

• All patients with radiographic evidence of BAI should undergo anti-impulse therapy with ß-blockade, if tolerated, coupled with antiplatelet therapy (81 mg aspirin).
• Observation alone with interval follow-up CT angiography within 30 days is appropriate for all intimal tears < 10 mm.
• Selective management of large intimal flaps < 10 mm is appropriate with repeat imaging within 7 days to assess for progression. Evidence of progression should be managed, when possible, with EVAR.
• All patients with an aortic external contour abnormality should be considered for semielective (≤ 1 week) EVAR if there is a high likelihood of survival from other associated injuries. These patients should be monitored with CT imaging as follows: 1 month, 6 months, 1 year, and every other year thereafter. Patients with hypotension on presentation and aortic arch hematoma > 15 mm should be repaired with EVAR methods on a more urgent basis.
• Intentional left subclavian artery coverage without revascularization is well tolerated in a majority of patients with BAI.
• Patients with traumatic brain injury and an aortic external contour abnormality should be considered for earlier repair if a deliberate increase in mean arterial pressure is deemed beneficial for the patient