There is no debate that CT imaging has undergone significant advancements in both image quality and image acquisition speed over the last two decades. This has resulted in CT imaging techniques and “pan scanning” becoming an essential part of the overwhelming majority of patients’ with blunt traumatic injuries initial evaluations. This increased fidelity of images and ubiquitous nature of CT in emergency departments has made identifying BTAI much easier. BTAI represents a spectrum of lesions that range from intimal tear to aortic rupture. Naturally, the treatment for all injuries is not the same. In 2009, we proposed a classification system based on the extent of injury to the anatomic layers of the aortic wall: intimal tears (Grade 1), intramural hematomas (Grade II), pseudoaneurysms (Grade III), and ruptures (Grade IV) (Fig. 11.1).

The SVS adopted this classification system in 2011 as part of its clinical practice guidelines for the treatment of BTAI [13]. While widely accepted as part of the SVS BTAI treatment guidelines, it is important to note that other grading scales have also been developed that take into account additional CT imaging findings, such as hemothorax and aortic dimensions, in the area of injury as well as to physiologic parameters at the time of ED presentation [15–18]. Due to lack of prospective trials evaluating treatment outcomes implementing these grading scales, only low-grade evidence is available in the literature supporting one scale over the other. Despite superiority of a single grading scale, it is imperative that some form of grading scale be systematically used when addressing treatment algorithms. Using the available treatment options appropriately is critical to optimizing successful outcomes in patients with BTAI.

As stated earlier, in 2011 the SVS tasked an expert panel to develop clinical practice guidelines for the treatment of BTAI [13]. After a systematic review and meta-analysis of the literature, the committee reached a consensus based on expert opinion. More definitive recommendations could not be reached due to the overwhelming “low-grade” evidence based primarily from single-center studies available for review [14]. The systematic review included 7,768 patients from 139 studies. The study revealed a significantly lower mortality rate in patients who underwent TEVAR, compared to OR, and nonoperative management (9 %, 19 %, and 46 %, respectively, P < .01). Based on this, the SVS Clinical Practice Guidelines suggest urgent endovascular repair for Grade II-IV injuries with suitable aortic anatomy once other injuries have been stabilized [13]. These recommendations are supported by the results of the only non-industry sponsored Level II data available in the literature from the AAST Aortic Injury Study Group reported in 2008 [3]. These results supported improved outcomes with initial blood pressure optimization, followed by delayed intervention after 24 hours, as compared to patients who underwent emergent repair within 24 hours of presentation [3]. What needs further refinement within the literature is to determine the exact optimal timing for aortic repairs based on grade and the natural course of aortic injuries if left untreated, especially in patients with lower grade BTAI. A more refined description of patient risk factors for early rupture after BTAI would also help define optimal timing for repair, as this complication almost invariably leads to mortality. Some centers have reported nonoperative management with anti-impulse therapy for Grade I and select Grade II injuries [15–18, 20]. The inclusion of Grade II injuries into nonoperative management directly conflicts with SVS guidelines but has been supported in a number of single-institution studies [15–18, 20]. The Achilles heel of nonoperative management in patients with BTAI is the notoriously poor compliance of this patient cohort with medical therapy and follow-up imaging protocols.

At present, the most impactful series in the literature on contemporary management of BTAI comes from two studies. The AAST prospective multicenter trial by Demetriades et al. and the Aortic Trauma Foundation (ATF) retrospective multicenter study, which was in press at the time of this writing [3, 21]. Both studies report similar trends and outcomes in regard to the use of TEVAR, mortality, and paraplegia rates. In the AAST study, 64.8 % of patients were treated with an endovascular approach and 35.2 % were treated with OR, with an overall mortality rate of 13.5 % [3]. Mortality with OR was 23.5 % compared to 7.2 % with endovascular repair (p value < 0.001) [3]. In regard to postoperative paraplegia, patients repaired with an open approach had an incidence of 2.9 %, all associated with bypass procedures, while an incidence of 0.8 % was found in patients repaired with an endovascular approach [3]. The solo paraplegia complication in the endovascular group was due to stent graft collapse and thrombosis [3]. The most striking finding in the AAST report was the significant number of device-related complications. In the group of patients repaired with an endovascular approach, 20 % experienced device-related complications [3]. Most of these complications were related to endoleaks (14.4 %), with the remaining complications related to access sites [3].

The 2014 Aortic Foundation multicenter study reported results from 382 patients from 9 American College of Surgeons (ACS) verified trauma centers [19]. The SVS grading scale was used with patients in the following distribution: 94 Grade 1 injuries, 68 Grade II injuries, 192 Grade III injuries, and 28 Grade IV injuries [21]. Nonoperative management was used as the initial method of treatment in 32.2 % of the patients with only two failures [21]. Both patients, one Grade II injury and one Grade IV, were subsequently repaired with TEVAR without complication [19]. The overall mortality rate for patients managed nonoperatively was 34.4 % with an aortic mortality rate of 9.8 % [19]. They represented a significantly older group of the cohort and predominantly consisted of Grade 1 injuries [19]. Of the patients repaired operatively, OR was selected in 16 % with a mortality rate of 8.6 % and an aortic-related mortality of 2.5 % [19]. The interesting finding in this group is that median time from admission to OR was 36.4 hours, with half of the patients being repaired within 6 hours of admission [19]. This is important to note as it could indicate the need for operative repair more urgently than endovascular resources could be mobilized. An endovascular approach with TEVAR was chosen in 52 % of the cohort with a hospital mortality rate of 8.6 % with an aortic-related mortality of 2.5 % [19]. The study reported 2 deaths during the operative placement of TEVAR, neither of which were due to the procedure itself [19]. The study also reported 6 TEVAR failures, with salvage coming in the form of 2 repeat TEVARS and 4 conversions to open approaches [19]. TEVAR complications consisted of 6 malpositioned endografts (3.0 %), 5 endoleaks (2.5 %), 1 incidence of paralysis (0.5 %), and 2 strokes (1.0 %) [19]. Coverage of the left subclavian artery was required in 41.4 % of the patients treated with TEVAR [19].

When the operative groups were compared directly, the results revealed that patients who were treated with OR had higher ISS scores, more likely to have mediastinal hematomas with associated compression, faster time to repair from admission and higher transfusion rates [21]. Overall complication rates were similar between operative approaches. When all treatment modalities were compared, the overall in-hospital mortality for all patients with BAI was 18.8 %, with 34.4 % in patients managed nonoperatively, 19.7 % for patients repaired with open techniques, and 8.6 % for those repaired with TEVAR (p = 0.021) [21]. Mortality as related to BAI Grading was 0 % in Grade I, 2.9 % in Grade II, 5.2 % in Grade 3, and 46.4 % in Grade 4 [21]. Most aortic-related deaths reported in this series occurred prior to patients having an opportunity for surgical intervention of any type (18/25 deaths) [21]. Of the patient deaths following operative intervention, all had an ISS > 25 [21]. Three of these seven deaths had a GCS of 3 upon arrival with head AIS scores >3, two required massive transfusions, three required emergent laparotomies and five dying within 24 hours of admission [21]. These findings represent the poly-trauma nature of these patients and the significant amount of force transferred as a result of deceleration injury mechanisms.

The study reported that the independent predictors of all-cause mortality were higher ISS scores, higher SVS BAI grades, low admission GCS, need for blood transfusion in the first 24 hours and nonoperative management [21]. When direct aortic-related mortality was analyzed, higher ISS, SVS grade of injury and chest AIS scores were predictive [21]. Ultimately, in this study cohort, intervention with TEVAR proved to be protective against aortic-related mortality.

While these landmark studies set the most recent benchmark for care of patients with BTAI, Karmy-Jones et al. provided a comprehensive review of the BTAI literature up until 2010. This report reviewed 62 retrospective reviews and six meta-analysis [16]. At that time, 25 papers were available comparing TEVAR to OR [16]. Using the key phrases in the above stated search strategy, eight additional studies were identified for review. All studies available in the literature comparing TEVAR to OR are available for review in Table 11.2.