Minimal Aortic Injury Research Articles

Minimal Aortic Injury Detected on Computed Tomography Angiography during Initial Trauma Imaging: Single Academic Level 1 Trauma Center Experience.

Minimal aortic injury (MAI), a subtype of acute traumatic aortic injury, is being increasingly recognized with better imaging techniques. Given conservative management, the role of follow-up imaging albeit important yet has to be defined. All trauma chest computed tomography angiographies (CTAs) at our center between January 2012 and January 2019 were retrospectively reviewed for presence of MAI. MAIs were generally reimaged at 24 to 72 hours and then at a 7- and 30-day interval. Follow-up CTAs were reviewed for stability, progression, or resolution of MAI, along with assessment of injury severity scores (ISS) and concomitant injuries, respectively. A total of 17,569 chest CTAs were performed over this period. Incidence of MAI on the initial chest CTA was 113 (0.65%), with 105 patients receiving follow-up CTAs. The first, second, third, and fourth follow-up CTAs were performed at a median of 2, 10, 28, and 261 days, respectively. Forty five (42.9%), 22 (21%), 5 (4.8%), and 1 (1%) of the MAIs were resolved by first, second, third, and fourth follow-up CTAs. Altogether, 21 patients showed stability (mean ISS of 16.6), and 11 demonstrated improvement (mean ISS 25.8) of MAIs. Eight patients had no follow-up CTA (mean ISS 21). No progression to higher-grade injury was observed. Advancing age decreased the odds of MAI resolution on follow-up. A possible trend (p-value 0.22) between increasing ISS and time to resolution of MAIs was noted. In our series of acute traumatic MAIs diagnosed on CTA imaging, there was no progression of injuries with conservative management, questioning the necessity of sequential follow-up imaging.

Outcomes and practice patterns of medical management of blunt thoracic aortic injury from the Aortic Trauma Foundation global registry

Objective: Blunt thoracic aortic injury (BTAI) is the second leading cause of death from blunt trauma. In the present study, we aimed to determine the outcomes of medical management (MM) for BTAI. We hypothesized from the results of several previously reported studies, that patients with a minimal aortic injury (BTAI grades 1 and 2) could safely be treated with definitive MM alone.

Outcomes and practice patterns of medical management of blunt thoracic aortic injury from the Aortic Trauma Foundation global registry

ObjectiveBlunt thoracic aortic injury (BTAI) is the second leading cause of death from blunt trauma. In the present study, we aimed to determine the outcomes of medical management (MM) for BTAI. We hypothesized from the results of several previously reported studies, that patients with a minimal aortic injury (BTAI grades 1 and 2) could safely be treated with definitive MM alone. MethodsThe Aortic Trauma Foundation international prospective multicenter registry was used to examine the demographics, injury characteristics, management, and outcomes of patients with BTAI. We analyzed a subset of patients for whom MM was initiated as definitive therapy. ResultsFrom November 2016 to April 2020, 432 patients (median age, 41 years; 76% male; median injury severity score, 34) with BTAI (Society for Vascular Surgery grade 1, 23.6%; grade 2, 14.4%; grade 3, 51.2%; grade 4, 10.9%) were evaluated. Of the 432 patients, 245 (57%) had received MM in the initial period and 114 (26.4%) had received MM as the planned definitive therapy (grade 1, 59.6%; grade 2, 23.7%; grade 3, 15.8%; grade 4, 0.9%). The most common mechanism of BTAI was a motor vehicle collision (60.4%). Hypotension was present on arrival in 74 patients (17.2%). Continuous titratable infusion of antihypertensive medication was used for 49.1%, followed by intermittent bolus administration (29.8%), with beta-blockers (74.6%) the most common agent used. Treatments were targeted to a goal systolic blood pressure for 83.3%, most often to a target goal systolic blood pressure <120 mm Hg (66.3%). The MM goals based on blood pressure control were attained in 64.0% (73 of 114). Twelve patients (10.5%; grade 1, 1; grade 2, 0; grade 3, 10; grade 4, 1) had required subsequent intervention after MM. Eleven patients (9.6%) had undergone thoracic endovascular aortic repair and one (0.9%) had required open repair for a grade 4 injury. The overall in-hospital mortality for patients selected for definitive MM was 7.9%. No aortic-related deaths had occurred in the patients receiving definitive MM. ConclusionsApproximately one in four patients with BTAI will receive MM as definitive therapy. The variation in the pharmacologic therapies used is considerable. MM for patients with minimal aortic injury (BTAI grades 1 and 2) is safe and effective, with a low overall intervention rate and no aortic-related deaths. These findings support the use of definitive MM for grade 2 BTAI.

Macrophage-biomimetic anti-inflammatory liposomes for homing and treating of aortic dissection

Aortic dissection (AD) is a life-threatening disease featured by the dissection of intimal layer and the formation of a blood-filled false lumen within the aortic wall. Recent studies revealed that the formation and progression of AD lesions is closely related to vascular inflammation and macrophage infiltration. However, the potential efficacy of anti-inflammatory therapy on the prevention and treatment of AD has not been extensively investigated. Herein, we proposed a biomimetic anti-inflammatory liposome (PM/TN-CCLP) co-loaded with curcumin and celecoxib (CC), modified with cell-penetrating TAT-NBD fusion peptide (TN), and further camouflaged by isolated macrophage plasma membrane (PM), as a potential nanotherapy for AD. In vitro results showed that PM/TN-CCLP exhibited low cytotoxicity and elevated cellular uptake by inflammatory macrophages, and prominently inhibited the transendothelial migration, inflammatory responses and ROS generation of macrophages. Moreover, the PM/TN-CCLP treatment significantly prevented the H2O2-induced smooth muscle cell apoptosis. In vivo experiments were performed on the acute and chronic AD mouse models, respectively. The results verified the elevated accumulation of PM-camouflaged liposome at the aorta lesions. Further, the anti-inflammatory liposomes, especially PM/TN-CCLP, could reduce the rupture rate of dissection, prevent the loss of elastic fibers, and reduce MMP-9 expression as well as macrophage infiltration in the aortic lesions. Notably, as compared with free drugs and TN-CCLP, the PM/TN-CCLP treatment displayed the longest survival period along with the minimal aortic injury on both acute and chronic AD mice. Taken together, the present study suggested that the macrophage-biomimetic anti-inflammatory nanotherapy would be a promising strategy for the prevention and therapy of aortic dissection.

Minimal Aortic Injury: Mechanisms, Imaging Manifestations, Natural History, and Management.

Over the last 2 decades, increased depiction of minimal aortic injury (MAI) in the evaluation of patients who have sustained trauma has mirrored the increased utilization and improved resolution of multidetector CT. MAI represents a mild form of blunt traumatic aortic injury (BTAI) that usually resolves or stabilizes with pharmacologic management. The traditional imaging manifestation of MAI is a subcentimeter round, triangular, or linear aortic filling defect attached to an aortic wall, representing a small intimal flap or thrombus consistent with grade I injury according to the Society for Vascular Surgery (SVS). Small intramural hematoma (SVS grade II injury) without external aortic contour deformity is included in the MAI spectrum in several BTAI classifications on the basis of its favorable outcome. Although higher SVS grades of injury generally call for endovascular repair, there is growing literature supporting conservative management for small pseudoaneurysms (SVS grade III) and large intimal flaps (>1 cm, unclassified by the SVS), hinting toward possible future inclusion of these entities in the MAI spectrum. Injury progression of MAI is rare, with endovascular aortic repair reserved for these patients as well as patients for whom medical treatment cannot be implemented. No consensus on the predetermined frequency and duration of multidetector CT follow-up exists, but it is common practice to perform a repeat CT examination shortly after the initial diagnosis. The authors review the evolving definition, pathophysiology, and natural history of MAI, present the primary and secondary imaging findings and diagnostic pitfalls, and discuss the current management options for MAI. Online DICOM image stacks are available for this article. ©RSNA, 2020.

Nonoperative management rather than endovascular repair may be safe for grade II blunt traumatic aortic injuries: An 11-year retrospective analysis.

The Society of Vascular Surgery (SVS) guidelines currently suggest thoracic endovascular aortic repair (TEVAR) for grade II-IV and nonoperative management (NOM) for grade I blunt traumatic aortic injury (BTAI). However, there is increasing evidence that grade II may also be observed safely. The purpose of this study was to compare the outcome of TEVAR and NOM for grade I-IV BTAI and determine if grade II can be safely observed with NOM. The records of patients with BTAI from 2004 to 2015 at a Level I trauma center were retrospectively reviewed. Patients were separated into two groups: TEVAR versus NOM. All BTAIs were graded according to the SVS guidelines. Minimal aortic injury (MAI) was defined as BTAI grade I and II. Failure of NOM was defined as aortic rupture after admission or progression on subsequent computed tomography (CT) imaging requiring TEVAR or open thoracotomy repair (OTR). Statistical analysis was performed using Mann-Whitney U and χ tests. A total of 105 adult patients (≥16 years) with BTAI were identified over the 11-year period. Of these, 17 patients who died soon after arrival and 17 who underwent OTR were excluded. Of the remaining 71 patients, 30 had MAI (14 TEVAR vs. 16 NOM). There were no failures in either group. No patients with MAI in either group died from complications of aortic lesions. Follow-up CT imaging was performed on all MAI patients. Follow-up CT scans for all TEVAR patients showed stable stents with no leak. Follow-up CT in the NOM group showed progression in two patients neither required subsequent OTR or TEVAR. Although the SVS guidelines suggest TEVAR for grade II-IV and NOM for grade I BTAI, NOM may be safely used in grade II BTAI. Therapeutic study, level IV.

Determinants and outcomes of nonoperative management for blunt traumatic aortic injuries

ObjectiveThe natural history and parameters for successful nonoperative management of blunt traumatic aortic injuries (BTAIs) involving the descending aorta are poorly understood. We examined our experience with nonoperative BTAI treatment (anti-impulse, blood pressure) and evaluated for determinants of successful outcomes. MethodsWe performed a review of our institutional prospective trauma registry database for all BTAI patients from 1999 to 2015. Computed tomography angiography was used to classify aortic injuries on the basis of severity: grade I, intimal tear; grade II, intramural hematoma; grade III, aortic pseudoaneurysm; and grade IV, free rupture. Grade IV injuries were excluded from nonoperative management. Baseline characteristics, clinical outcomes, and follow-up lesion resolution were compared within the medically managed cohort and between surgical and nonoperative groups using univariate and multivariable analysis. ResultsAmong 338 BTAI patients admitted between 1999 and 2015, 67 BTAI patients were managed nonoperatively; 26 (54%) had grade I BTAI, 22 (46%) had grade II, and 2 (4%) had grade III. Both grade III injuries required a late thoracic endovascular aortic repair after initial medical management and were excluded from analysis. In all, 48 were managed with initial medical therapy, and the remaining 19 died on admission or before definitive treatment. Among the 48 medically managed, the median age was 34 years, and 14 (29%) were female. Six of the 48 (12%) were transferred from other facilities. There was no significant difference in baseline characteristics or early outcomes between BTAI grades. Median injury resolution time was 39 days for grade I and 62 days for grade II (P = .03). Compared with a surgical cohort, BTAI grade and Abbreviated Injury Scale score for the chest were the only significant determinants of propensity to operate. ConclusionsBased on these limited data, it appears that patients with minimal aortic injuries (grades I and II) may be managed medically, with the majority resolving within 8 weeks. Minimal aortic injury is associated with low mortality and excellent intermediate-term outcomes. Further prospective studies are required to validate these findings.

Advances in Imaging and Management Trends of Traumatic Aortic Injuries.

Acute traumatic aortic injury (ATAI) is a life-threatening injury. CT is the imaging tool of choice, and the knowledge of direct and indirect signs of injury, grading system, and current management protocol helps the emergency radiologist to better identify and classify the injury and provide additional details that can impact management options. Newer dual-source CT technology with ultrafast acquisition speed has also influenced the appropriate protocol for imaging in patients with suspected ATAI. This review highlights the imaging protocol in patients with blunt trauma, CT appearance and grading systems of ATAI, management options, and the role of the multidisciplinary team in the management of these patients. We also briefly review the current literature on the definition, treatment, and follow-up protocol in patients with minimal aortic injury.

Determinants and Outcomes of Nonoperative Management of Blunt Traumatic Aortic Injuries

Natural history and parameters for successful nonoperative management of blunt traumatic aortic injuries (BTAIs) are poorly understood. We examined our experience with nonoperative BTAI treatment (anti-impulse, blood pressure) and evaluated for determinants of successful outcomes. Review of trauma registry database for all patients with BTAIs from 2004 to 2015 was performed. Computed tomographic angiography was used to classify aortic injuries: grade 1, intimal tear; grade 2, intramural hematoma; grade 3; aortic pseudoaneurysm; and grade 4, free rupture. Grade 4 injures were excluded from nonoperative management. Baseline, clinical outcomes, and follow-up lesion resolution were compared within the medically managed cohort and between surgical and nonoperative groups using univariate and multivariable analysis. Among 338 patients with BTAI admitted between 2004 and 2015, 67 patients with BTAIs were managed nonoperatively, 48 were managed with initial medical therapy, and the remaining 19 died on admission or prior to definitive treatment (Fig 1). Among the 48 medically managed, median age was 34 years, and 13 (27%) were female. Six of 48 (12%) were transferred from other facilities. Twenty-five (52%) had grade 1 BTAI, 21(44%) had grade 2, and two (4%) had grade 3. No baseline or early outcomes were significantly different between BTAI grades. Median injury resolution time was 39 days in grade 1 and 62 days for grade 2 (P = .09; Fig 2). Both grade 3 injuries required a late thoracic endovascular aneurysm repair following initial medical management. When compared with a surgical cohort, BTAI grade and Abbreviated Injury Scale (AIS) chest were the only significant determinants of propensity to operate. Based on this limited data, it appears that grade 1 and 2 injuries may be managed medically with the majority resolving within 8 weeks. Minimal aortic injury is associated with low mortality and excellent intermediate-term outcomes. Further prospective studies are required to validate these findings.Fig 2Cumulative healing rate by injury grade.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Call for a new classification system and treatment strategy in blunt aortic injury

The current Society for Vascular Surgery (SVS) classification scheme for blunt aortic injury (BAI) is descriptive but does not guide therapy. We propose a simplified classification scheme based on our robust experience with BAI that is descriptive and guides therapy. Patients presenting with BAI between January 1999 and September 2014 were identified from our institution's trauma registry. We divided patients into eras by time. Era 1: before the first United States Food and Drug Administration (FDA)-approved thoracic endovascular aortic repair (TEVAR) device (1999-2005); era 2: FDA-approved TEVAR devices (2005-2010); and era 3: FDA-approved BAI-specific devices (2010-present). Baseline demographic information, Injury Severity Score, hospital details, and survival were collected and compared. Our classification scheme was minimal aortic injury, SVS grade 1 and 2; moderate aortic injury, SVS grade 3; and severe aortic injury, SVS grade4. We identified 226 patients with a diagnosis of BAI: 75 patients in era 1, 84 in era 2, and 67 in era 3. Mean Injury Severity Score was 39.5 (range, 16-75). The BAI-related in-hospital mortality was significantly higher before endovascular introduction in era 1 (14.6% vs 4.8%; P= .03), but was not significantly different between eras 2 and 3 or before and after BAI-specific devices were introduced (P= .43). Of 146 patients (64.6%) who underwent aortic intervention, 91 underwent endovascular repair, and 55 underwent open repair. All but nine patients (94%) had a moderate or severe injury. Survival across all three eras of patients undergoing operative intervention was 80.2%. Survival in eras 2 and 3 was higher than in era 1 (86.4% vs 73.8%) but was not significant (P= .38). Of 47 patients in eras 2 and 3 with minimal aortic injury, 45 (96%) were managed nonoperatively, with no BAI-related deaths. After 2007, follow-up imaging was obtained in 38 patients (80%) with minimal aortic injury, and progression was not observed. Computed tomography scans showed the injury in 13 patients appeared stable, 19 had complete resolution (50%), and 6 had a decreasing size of injury. Our experience confirms that BAI-related mortality for patients who survive to presentation is now 5%. From our findings during the past 15years, we propose simplification of the SVS grading criteria of BAI into minimal, moderate, and severe based on treatment differences among the three groups. Minimal aortic injury can be successfully managed nonoperatively without mandatory follow-up imaging. Moderate aortic injury can be managed semielectively with TEVAR, and severe aortic injury, requires emergency TEVAR.

PC10. Selective Nonoperative and Delayed Operative Approaches for the Management of Grade III Blunt Traumatic Aortic Injury

Blunt traumatic aortic injury (BAI) is a condition associated with high morbidity and mortality. Nonoperative management is advocated for patients with minimal aortic injury (grade I), but for grade II-IV, BAI operative repair remains the standard of care as recommended by the Society for Vascular Surgery (SVS). The SVS classifies blunt traumatic aortic pseudoaneurysms as grade III injuries and recommends repair using thoracic endovascular aortic repair (TEVAR). We have observed significant variability among severity of grade III BAI and have adopted a management strategy consisting of immediate TEVAR (<24 hours), delayed TEVAR (>24 hours), and selective nonoperative approaches for the management of these injuries. We therefore evaluated outcomes with these approaches in comparison with immediate TEVAR. We retrospectively identified all BAI presenting to an academic level I trauma center over a 15-year period (2000-2014). Computed tomography cross-sectional images were reviewed by a radiologist and graded according to SVS guidelines (grade I-IV). Pseudoaneurysm size was measured in three dimensions. Demographics, injury severity score (ISS), and outcomes were recorded. Patients were selected for operative intervention based on the size and morphology of the pseudoaneurysm, coexisting burden of traumatic injury, age, and comorbidities, at the discretion of the vascular surgeon. Patients were grouped according to management strategy: immediate TEVAR (i-TEVAR, ≤24 hours of admission), delayed TEVAR (d-TEVAR, >24 hours from admission), and nonoperative management (nonop). Outcomes in these groups were compared. Primary outcome measures were overall mortality and aortic-related mortality (death due to aortic injury). We identified 153 patients with grade III BAI. Mean age was 39.3 years, and mean ISS was 38.6. Patients were excluded if they did not have meaningful possibility of recovery from traumatic injuries (n = 18) or if they underwent open repair (n = 48). The remaining patients were grouped as follows: i-TEVAR (n = 32), d-TEVAR (n = 16), and nonop (n = 37). ISS was similar in all three groups (P = NS). TEVAR was performed a median of 5 days and a mean of 30 days after injury in the d-TEVAR group. Overall mortality was 15.6% in the i-TEVAR group at 3.1 years’ mean follow-up, 6% in the d-TEVAR group at 1.5 years, and 18.9% in the nonop group at 1.7 years (P = NS). Aortic-related mortality was 6% for i-TEVAR, 0% for d-TEVAR, and 3% in the nonoperative group (P = NS). Mean maximum pseudoaneurysm dimension was 33 mm for i-TEVAR, 33 mm for d-TEVAR, and 23 mm in the nonop group (P = .0003 vs i-TEVAR, P = .005 vs d-TEVAR). Patients presenting with grade III BAI may be safely managed with a delayed operative or nonoperative approach in selected circumstances with minimal associated mortality. Delayed TEVAR provides a window of opportunity for selection of patients for TEVAR who do not succumb to their other traumatic injuries. Nonoperative management may be appropriate for patients presenting with smaller pseudoaneurysms, as we did not observe rupture in pseudoaneurysms measuring ≤31 mm in maximum diameter in patients managed nonoperatively. Mortality in all these groups was high, primarily as a result of other traumatic injuries, and therefore, appropriate selection of patients for TEVAR must rely on sound clinical judgement.

Abstract No. 403 - Initial and follow-up imaging findings of minimal aortic injury

Abstract No. 403 - Initial and follow-up imaging findings of minimal aortic injury

Blunt abdominal aortic injury: a Western Trauma Association multicenter study.

Blunt abdominal aortic injury (BAAI) is a rare injury. The objective of the current study was to examine the presentation and management of BAAI at a multi-institutional level. The Western Trauma Association Multi-Center Trials conducted a study of BAAI from 1996 to 2011. Data collected included demographics, injury mechanism, associated injuries, interventions, and complications. Of 392,315 blunt trauma patients, 113 (0.03%) presented with BAAI at 12 major trauma centers (67% male; median age, 38 years; range, 6-88; median Injury Severity Score [ISS], 34; range, 16-75). The leading cause of injury was motor vehicle collisions (60%). Hypotension was documented in 47% of the cases. The most commonly associated injuries were spine fractures (44%) and pneumothorax/hemothorax (42%). Solid organ, small bowel, and large bowel injuries occurred in 38%, 35%, and 28% respectively. BAAI presented as free aortic rupture (32%), pseudoaneurysm (16%), and injuries without aortic external contour abnormality on computed tomography such as large intimal flaps (34%) or intimal tears (18%). Open and endovascular repairs were undertaken as first-choice therapy in 43% and 15% of cases, respectively. Choice of management varied by type of BAAI: 89% of intimal tears were managed nonoperatively, and 96% of aortic ruptures were treated with open repair. Overall mortality was 39%, the majority (68%) occurring in the first 24 hours because of hemorrhage or cardiac arrest. The highest mortality was associated with Zone II aortic ruptures (92%). Follow-up was documented in 38% of live discharges. This is the largest BAAI series reported to date. BAAI presents as a spectrum of injury ranging from minimal aortic injury to aortic rupture. Nonoperative management is successful in uncomplicated cases without external aortic contour abnormality on computed tomography. Highest mortality occurred in free aortic ruptures, suggesting that alternative measures of early noncompressible torso hemorrhage control are warranted. Epidemiologic study, level III; therapeutic study, level IV.

Minimal aortic injury of the thoracic aorta: imaging appearances and outcome

The aim of this study is to describe the frequency, computed tomographic angiography (CTA) imaging appearance, management, and outcome of patients who present with minimal thoracic aortic injury. This retrospective study was Institutional Review Board-approved. Eighty-one patients with blunt traumatic aortic injuries (BTAI) were identified between 2004 and 2008, comprising 23 patients with minimal aortic injury (MAI) (mean age, 43.2 years ±18.2 years; 12 males and 11 females) and 58 patients with non-minimal aortic injury (mean age, 42.6 years ±22.7 years). CTA imaging was reviewed for each patient to differentiate those with MAI from those with non-MAI BTAI. Inclusion criteria for MAI on CTA were: post-traumatic abnormality of the internal contour of the aorta wall projecting into the lumen, intimal flap, intraluminal filling defect, intramural hematoma, and no evidence of an abnormality to the external contour of the aorta. Relevant follow-up imaging for MAI patients was also reviewed for resolution, stability, or progression of the vascular injury. The electronic medical record of each patient was reviewed and mechanism of injury, injury severity score, associated injuries, type and date of management, outcome, and days from injury to last medical consultation. Minimal aortic injury represented 28.4 % of all BTAI over the study period. Mean injury severity score (37.1), age (43.2 years), and gender did not differ significantly between MAI and non-MAI types of BTAI. Most MAI occurred in the descending thoracic aorta (16/23, 69 %). Without operative or endovascular repair, there was no death or complication due to MAI. One death occurred secondary to MAI (4.4 %) in a patient who underwent endovascular repair and surgical bypass, compared with an overall mortality rate of 8.6 % in the non-MAI BTAI group (p = 0.508). The most common CT appearance of MAI was a rounded or triangular intra-luminal aortic filling detect (18/23 patients, 78 %). In a mean of 466 days of clinical follow-up, no complications were observed in survivors treated without endovascular repair or operation. Minimal aortic injury is identified by multi-detector row CT in more than a quarter of cases of BTAI and has a low mortality. Conservative management is associated with an excellent outcome.

Natural history of grade I-II blunt traumatic aortic injury

Endovascular aortic repair has revolutionized the management of traumatic blunt aortic injury (BAI). However, debate continues about the extent of injury requiring endovascular repair, particularly with regard to minimal aortic injury. Therefore, we conducted a retrospective observational analysis of our experience with these patients. We retrospectively reviewed all BAI presenting to an academic level I trauma center over a 10-year period (2000-2010). Images were reviewed by a radiologist and graded according to Society for Vascular Surgery guidelines (grade I-IV). Demographics, injury severity, and outcomes were recorded. We identified 204 patients with BAI of the thoracic or abdominal aorta. Of these, 155 were deemed operative injuries at presentation, had grade III-IV injuries or aortic dissection, and were excluded from this analysis. The remaining 49 patients had 50 grade I-II injuries. We managed 46 grade I injuries (intimal tear or flap, 95%), and four grade II injuries (intramural hematoma, 5%) nonoperatively. Of these, 41 patients had follow-up imaging at a mean of 86 days postinjury and constitute our study cohort. Mean age was 41 years, and mean length of stay was 14 days. The majority (48 of 50, 96%) were thoracic aortic injuries and the remaining two (4%) were abdominal. On follow-up imaging, 23 of 43 (55%) had complete resolution of injury, 17 (40%) had no change in aortic injury, and two (5%) had progression of injury. Of the two patients with progression, one progressed from grade I to grade II and the other progressed from grade I to grade III (pseudoaneurysm). Mean time to progression was 16 days. Neither of the patients with injury progression required operative intervention or died during follow-up. Injury progression in grade I-II BAI is rare (~5%) and did not cause death in our study cohort. Given that progression to grade III injury is possible, follow-up with repeat aortic imaging is reasonable.

Patterns and Management of Blunt Abdominal Aortic Injury

Blunt abdominal aortic injury (BAAI) is historically associated with significant morbidity and mortality. Our institutional experience was analyzed to define current patterns of injury and to help guide management. Adult patients with BAAI between January 2000 and July 2011 were identified from our trauma registry. Medical, radiographic, and autopsy records were reviewed for relevant clinical data. Management and outcomes were compared between patients with minimal aortic injury limited to the intima (MAI) compared to more significant aortic injury (SAI). Nine patients had MAI and 8 had SAI, including 2 dissections, 2 pseudoaneurysms, 2 branch avulsions, 1 thrombosis, and 1 transection. The MAI and SAI groups had similar demographics and patterns of injury, and all patients had significant polytrauma, with a mean injury severity score of 42. More MAI than SAI patients were managed nonoperatively (100% vs. 38%; P=0.01). All observed patients underwent repeat imaging during the index admission, 85% within 72 hours, and no observed lesions led to malperfusion, death, or progression during the index admission. One MAI progressed to a pseudoaneurysm within 8 months. Five SAI patients underwent aortic-related repairs, including 2 endovascular stent grafts, 2 open primary repairs, and 1 axillobifemoral bypass. Overall, 15 (88%) patients underwent procedures for any injury-9 required laparotomy (53%) and 2 underwent thoracotomy. There were 6 (35%) deaths, 2 attributable to aortic injury-1 from hemorrhage and 1 from hyperkalemic cardiac arrest after prolonged ischemia from infrarenal aortic occlusion. Among patients who survived the initial resuscitation, SAI was associated with a significantly higher mortality rate compared to MAI (50% vs. 0%; P=0.03). Patients with MAI are at low risk of complications and may be considered for observation. Patients with SAI requiring intervention manifest clinically and/or radiographically at presentation. Those not associated with bleeding, malperfusion, or thromboembolism may be observed with interval imaging. For all observed patients, long-term surveillance is required to document complete resolution or stability, because even MAI can progress to a more complex lesion.

Validating Common Carotid Artery Stenosis by Duplex Ultrasound With Carotid Angiogram or Computed Tomographic Angiography Scan

Objectives: Endovascular aortic repair has revolutionized the management of blunt aortic trauma. However, debate continues about the extent of injury requiring endovascular repair, particularly with regard to minimal aortic injury. Therefore, we conducted a retrospective observational analysis of our experience with these patients. Methods: Weretrospectively reviewedall blunt traumatic aortic injuries at an academic Level I trauma center over a tenyear period (2001-2010). Images were reviewed by a radiologist and graded according to SVS guidelines (Grade I-IV). Demographics, injury severity, and outcomes were recorded. Results: We identified214patientswithblunt injuries to the thoracic or abdominal aorta. 115 were deemed operative injuries at presentation and were excluded from analysis. The remaining 99 were observed. On presentation, 54 had minimal (Grade I or II) injury. Of these, 43 had follow-up imaging at a mean of 102 days postinjury and constitute our study cohort. Mean age was 39 years and mean length of stay was 16 days. Forty-one patients (95%) had Grade I injury (intimal flap) and two patients had Grade II injury (medial hematoma). Forty (93%) were thoracic aortic injuries and the remaining were abdominal. On follow-up imaging, 23 of 43 (54%) had complete resolution of injury, 18 (42%) had no change in aortic injury, and two (5%) had progression (enlargement) of injury. Of the 2 patients with progression, one progressed fromGrade I to Grade II and one progressed from Grade I to Grade III (pseudoaneurysm). Mean time to progression was 16 days. Neither of the patients with injury progression required operative intervention. No patients were operated on or died from a grade I or II aortic injury. Conclusions: Injury progression in Grade I-II blunt aortic injury is rare (w5%) and did not cause death in our study cohort. Since progression to Grade III injury is possible, follow-up with repeat aortic imaging is reasonable.

Natural history of minimal aortic injury following blunt thoracic aortic trauma.

Endovascular repair of blunt traumatic thoracic aortic injuries (BTAI) is common at most trauma centres, with excellent results. However, little is known regarding which injuries do not require intervention. We reviewed the natural history of untreated patients with minimal aortic injury (MAI) at our centre. We conducted a retrospective database review to identify all patients with a BTAI between October 2008 and March 2010. The cohort comprised patients initially untreated because of the lesser degree of injury of an MAI. We reviewed initial and follow-up computed tomography (CT) scans and clinical information. We identified 69 patients with a BTAI during the study period; 10 were initially untreated and were included in this study. Degree of injury included intimal flaps (n = 7, 70%), pseudoaneurysms with minimal hematoma (n = 2, 20%) and circumferential intimal tear (n = 1, 10%). Six (60%) patients were male, and the median age was 40 years. Duration of clinical follow-up ranged from 1 month to 6 years (median 2 mo) after discharge, whereas CT radiologic follow-up ranged from 1 week to 6 years (median 6 wk). Seven (70%) patients had complete resolution or stabilization of their MAI, 1 (10%) with circumferential intimal tear showed extension of the injury at 8 weeks postinjury and underwent successful repair, and 2 (20%) were lost to follow-up. There appears to be a subset of patients with BTAI who require no surgical intervention. This includes those with limited intimal flaps, which often resolve. Radiologic surveillance is mandatory to ensure MAI resolution and identify any progression that might prompt repair.

Minimal Aortic Injury After Blunt Trauma: Selective Nonoperative Management Is Safe

An increasing number of minimal aortic injuries (MAIs) are being identified with modern computed tomography (CT) imaging techniques. The optimal management and natural history of these injuries are unknown. We have adopted a policy of selective multidisciplinary nonoperative management of MAI. This study examines our experience with these patients from July 2004 to June 2009. Retrospective chart review of all blunt trauma patients who underwent chest CT angiography to evaluate for blunt aortic injury (BAI) was undertaken. All patients deemed to have a MAI were managed nonoperatively, and those with a severe aortic injury underwent repair. Data collected included age, mechanism of injury, Injury Severity Score, type and location of aortic injury, intensive care unit length of stay (LOS), overall LOS, ventilator days, disposition, and mortality. In addition, all BAIs were graded according to the Presley Trauma Center CT Grading System of Aortic Injury. Forty-seven patients with BAI were identified. Thirty-two were classified as severe injuries, and 15 were considered MAI (32%). Nineteen underwent operative repair, 13 underwent endovascular stent graft repair, and 15 were managed nonoperatively. The average Injury Severity Score was 31 ± 10, and the average age was 44 ± 20 with no significant difference across treatment groups. There was no difference in overall or intensive care unit LOS. The nonoperative group had a shorter duration of ventilator days (1.1 vs. 4.28, p = 0.02). There were five deaths, none in the nonoperative group. None of these patients required subsequent intervention. All nonoperative patients had follow-up imaging at median of 4 days; on CT chest angiography, five injuries had resolved, eight had stable intimal flaps or pseudoaneurysm, and two had no detectable injury on subsequent aortogram. Almost one-third of our BAI were safely managed nonoperatively. Patients with MAI should be considered for selective nonoperative management in a multidisciplinary approach with close radiographic follow-up. We recommend that patients with MAIs should be considered for selective nonoperative management.

Vancouver simplified grading system with computed tomographic angiography for blunt aortic injury

Delineation of blunt aortic injury by computed tomographic angiography guides management of this potentially fatal injury. Two existing grading systems are problematic to apply and not linked to outcomes. A simplified computed tomographic angiography-based grading system, linked to clinical outcomes, was developed, and feasibility and reliability were evaluated. Retrospective review was performed of all blunt aortic injury cases presenting to a single provincial quaternary referral center designated for blunt aortic injury management between 2001 and 2009. Management, associated injuries, hospital survival, and cause of death were determined. Initial computed tomographic angiography was reviewed, and injuries were graded according to the new Vancouver simplified grading system by 2 study authors. Three additional trauma radiologists then graded the aortic injuries with the 2 existing systems and the simplified system. Interrater reliability was determined. Forty-eight patients were identified. Two had minimal aortic injury (grade I), 7 had an intimal flap larger than 1 cm (grade II), 32 had traumatic pseudoaneurysm (grade III), 6 had active contrast extravasation (grade IV), and 1 could not be rated. Survivals were 100%, 90%, and 33% for grades I and II, III, and IV, respectively. Of grade III injuries, 14% were medically managed, 68% repaired endovascularly, and 18% repaired with open surgery. Interrater correlation was best with the simplified score, with only 0.5% of cases unable to be classified. The Vancouver simplified blunt aortic injury grading system is easy to use and correlates with clinical outcomes. Prospective external validation is required.