A multicenter experience of the management of collapsed thoracic endografts

From the Society for Vascular Surgery

A multicenter experience of the management of collapsed thoracic endografts Rami O. Tadros, MD,a Evan C. Lipsitz, MD,b Rabih A. Chaer, MD,c Peter L. Faries, MD,a Michael L. Marin, MD,a and Jae-Sung Cho, MD,c New York and Bronx, NY; and Pittsburgh, Pa Objectives: Thoracic endograft collapse after thoracic endovascular aortic repair (TEVAR) is a potentially devastating complication. This study evaluates the management of thoracic stent graft collapse. Methods: A multicenter review of thoracic stent graft collapse was performed from 2005 to 2009. Diagnosis and preoperative planning was performed by computed tomography angiography (CTA). Outcome measures included success of endovascular salvage, postoperative complications, and conversion to open repair. Results: Eleven patients (10 men) with thoracic endograft collapse were identified. Mean age was 41.2 years old (range, 21-66 years). Indications for the index TEVAR were traumatic aortic transections in 8 patients and acute type B dissections in 3 patients. All were initially treated with the TAG endoprosthesis (Gore and Associates, Flagstaff, Ariz). The median duration from initial repair to diagnosis of collapse was 9 days (range, 1 day-38 months). All collapses were initially treated by endovascular means using another TAG device in 7 patients, a Talent (Medtronic, Santa Rosa, Calif) thoracic stent graft in 3 patients, and a Palmaz (Cordis Endovascular, Warren, NJ) stent in 1 patient. In 1 patient, the secondary TAG did not resolve the collapse and required a Palmaz stent placement. Technical success rate was 91%, while re-expansion of the collapsed endograft was achieved in all patients. Early and late complications were observed in 3 patients. Delayed (>30 days) open conversion with device explantation was performed for an aortoesophageal fistula, physiological aortic coarctation, and prevention of a recurrent collapse in 1 patient each. There were no perioperative deaths or recurrent collapses. Conclusion: Endograft collapse can be successfully managed by endovascular techniques in most cases. Redo-TEVAR using high radial force devices should be considered the initial treatment of choice. Late endograft-related complications after treatment of collapsed endografts are not uncommon and can be safely managed by open conversion. ( J Vasc Surg 2011;53:1217-22.)

Thoracic endovascular aortic repair (TEVAR) has been established as the preferential therapeutic modality for treatment of intact aneurysms of the descending thoracic aorta given its superior early and late outcomes compared with direct open repair.1-4 Its application has also gained a wide acceptance to treatment of acute thoracic aortic pathologies based on its favorable outcomes in comparison to open repair.5,6 However, to date, there exist no commercially available devices that are pathology-specific and satisfy the differential engineering considerations for the spectrum of thoracic aortic pathologies. Rare, but increasingly noted endograft-related complications, physiological aortic coarctation, and endograft collapse have been reported when used for, although not specific to, nonaneurysmal pathologies.7-16 These compliFrom the Division of Vascular Surgery, Mount Sinai Medical Centera; the Division of Vascular Surgery, Montefiore Medical Centerb; and the Division of Vascular Surgery, University of Pittsburgh School of Medicine.c Competition of interest: none. Presented at the 2010 Vascular Annual Meeting of the Society for Vascular Surgery, Boston, Mass, June 10-13, 2010. Reprint requests: Jae-Sung Cho, MD, Associate Professor of Surgery, University of Pittsburgh School of Medicine, Division of Vascular Surgery, 200 Lothrop Street, PUH A 1010, Pittsburgh, PA 15213 (e-mail: [email protected]). The editors and reviewers of this article have no relevant financial relationships to disclose per the JVS policy that requires reviewers to decline review of any manuscript for which they may have a competition of interest. 0741-5214/$36.00 Copyright © 2011 by the Society for Vascular Surgery. doi:10.1016/j.jvs.2010.10.119

cations can lead to devastating consequences, including reperfusion of the injured or dissected aortic segment and end-organ malperfusion. Herein, a multicenter experience with collapsed thoracic endografts and its management are reported. METHODS A retrospective chart review of medical records at the University of Pittsburgh Medical Center (Pittsburgh, Pa), Mount Sinai Medical Center (New York, NY), and Montefiore Medical Center (Bronx, NY) identified 11 patients who presented with thoracic endograft collapse from January 2005 to December 2009. The initial TEVAR was considered as the index procedure. All stent graft collapses were confirmed by computed tomographic angiography (CTA). This study was approved by the Institutional Review Board of each respective institution. Baseline patient characteristics and perioperative variables were evaluated, including the type of device used, length of aortic coverage, and adjunctive procedures used. Postoperative follow-up data were also collected. Clinical outcomes, including endograft salvage and graft-related complications were recorded. Postoperative imaging (CTA) protocol varied slightly among the institutions, but in general it was obtained before discharge, and then at 1 month, 3 months, and then annually thereafter, unless otherwise indicated as per CT findings or clinical suspicion. The method of repair (endovascular vs open) was determined by the operating surgeon. 1217

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Table I. Patient characteristics, aortic pathology, and index TEVAR

Pt #

Age

Gender

Aortic pathology

1 (RI)

21

M

2 (MS)

66

F

Traumatic TBAD (pseudoaneurysm) TAT

3 (MS) 4 (MF) 5 (UP) 6 (UP) 7 (UP) 8 (UP) 9 (RI)

21 34 50 21 43 41 36

M M M M M M M

TAT TAT TAT TAT TAT TAT TAT

10 (UP)

63

M

11 (UP)

57

M

Spontaneous TBAD (rupture) Spontaneous TBAD (refractory pain)

Proximal aortic diameter

Proximal landing zone

TAG 26 ⫻ 10

24

3

No

TAG 34 ⫻ 10, 31 ⫻ 10, 26 ⫻ 10 TAG 28 ⫻ 10 TAG 26 ⫻ 10 TAG 28 ⫻ 15 TAG 26 ⫻ 10, 26 ⫻ 10 TAG 28 ⫻ 10 TAG 28 ⫻ 10 TAG 26 ⫻ 10

28

3

No

24 20 23 22 24 24 28

3 3 3 3 3 3 2

TAG 34 ⫻ 15, 37 ⫻ 10

32

2

TAG 31 ⫻ 10

28

3

No No No No No No LCCA-LSA bypass 1 month later for salvage of L arm arteriovenous fistula LSA-LCCA transposition for type I endoleak No

Initial device and size (mm ⫻ cm)

LSA revascularization?

F, Female; LCCA, left common carotid artery; LSA, left subclavian artery; M, male; MF, Montefiore Medical Center; MS, Mount Sinai Medical Center; RI, referring institution; TAT, traumatic aortic transection; TBAD, type B aortic dissection; TEVAR, thoracic endovascular aneurysm repair; UP, University of Pittsburgh Medical Center.

RESULTS Eleven patients (10 men and 1 women) with thoracic endograft collapse were identified (Table I) from a prospectively collected database from each institution. The distribution of cases from each institution is detailed in Table I. The total numbers of TEVAR cases done during the study period at each institution are as follows: the University of Pittsburgh, 120; Mount Sinai, 81; and Montefiore, 51; of which 43, 6, and 3 were for traumatic aortic transections from the respective institutions. The mean age was 41.2 years (range, 21-66 years). The indications for the index TEVAR were traumatic aortic transection in 8 patients and acute complicated type B aortic dissection in 3 patients. All patients were initially treated with TEVAR using the TAG endoprosthesis (Gore and Associates, Flagstaff, Ariz). The left subclavian artery (LSA) was covered in 2 patients and with concomitant revascularization in 1 patient. In the other patient (patient #9), a left common carotid artery (LCCA) to LSA bypass was performed 1 month later to preserve a left arm hemodialysis access arteriovenous fistula (Table II). An iliac conduit was used in 1 patient only. The median duration from the time of the index TEVAR to the recognition of stent graft collapse was 9 days (range, 1 day-38 months; Table II); 8 of the 11 patients had the collapse diagnosed within 30 days of and during the same hospitalization of the device implantation. Endograft collapse occurred in the proximal segment in 10 patients and in the distal part in 1 patient. Most of the collapses were asymptomatic and detected by routine imaging studies; symptoms were present in only 4 patients (36.4%; Table II). All collapses were initially treated by endovascular means and re-expansion was achieved in all patients. In 1 patient, an additional TAG device did not achieve reexpansion, thereby requiring a Palmaz stent (Cordis Endo-

vascular, Warren, NJ) placement as detailed below. Technical success rate was 91% (10 of 11). High radial force devices were used in 4 patients: the Talent thoracic stent grafts (Medtronic, Santa Rosa, Calif) in 3 patients and the Palmaz stents in 1 patient, with successful re-expansion in all. The TAG endograft was used in the remaining 7 patients with re-expansion achieved in 6 patients. The 1 patient (patient #11) with a persistent collapse, initially had undergone a TEVAR using a TAG device for an acute type B dissection. The patient was noted to have a collapse and underwent an additional TAG placement 3 days later. A persistent collapse was noted on a follow-up CTA, and the patient was treated with a Palmaz stent 4 days later. An unrecognized iatrogenic injury in the ascending aorta had occurred at the time of Palmaz placement (Fig 1) that was not detected until 8 days later. The patient underwent an uncomplicated open repair of type A dissection with preservation of the endograft. Two patients had LSA coverage at the secondary intervention without its revascularization. Balloon angioplasty was initially attempted in 5 patients but was successful in none. There were no mortalities with re-expansion achieved in all patients. The cumulative complication rate was 27% (3 of 11). Early (⬍30 days) complications occurred in 1 patient: persistent collapse and an iatrogenic type A dissection as detailed above. Late (⬎30 days) graft-related complications, an aortoesophageal fistula, and a physiological coarctation developed at 1 month and 7 months after secondary TEVAR, respectively; these were successfully treated by open conversion with device explantation as reported earlier.7,17 Endograft preservation was achieved in 8 patients (72.7%). In addition to the 2 aforementioned patients, 1 additional patient underwent elective open conversion.

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Tadros et al 1219

Table II. Treatment for collapse and clinical outcomes Time interval: TEVAR to collapse

Collapse site

Sx/findings with collapse

1 (MS)

30 days

Proximal

2 (MS)

2 days

Proximal

Lower extremity malperfusion None

3 (MS)

7 days

Proximal

4 (MF)

20 days

Proximal

Lower extremity malperfusion None

5 (UP)

5 months

Proximal

Chest pain

6 (UP)

32 days

Proximal

None

7 (UP)

23 days

Proximal

None

8 (UP)

8 days

Proximal

None

9 (UP)

38 months

Proximal

Paraplegia (resolved)

10 (UP)

1 day

Mid

None

11 (UP)

3 days

Proximal

None

Pt #

Treatment Talent, proximal extension without LSA coverage Talent, proximal extension with LSA coverage Talent, proximal extension without LSA coverage Palmaz, proximal extension without LSA coverage TAG, proximal extension with LSA coverage TAG, proximal extension with LSA coverage TAG, without proximal extension TAG, without proximal extension TAG, with proximal extension (severe “bird-beak”) TAG, without proximal extension TAG ⫹ Palmaz proximally without proximal extension; TAG distal extension

Complications

Endograft salvage?

Follow-up duration from secondary procedure

None

Yes

None

Yes

Lost to follow-up 2 months

None

Yes

3 months

None

Yes

Lost to follow-up

AEF

4.3 yearsa

Physiological aortic coarctation None

No, explanted No, explanted Yes

None

Yes

None

No, explanted

Lost to follow-up 3 monthsa

None

Yes

4 months

Failure to open the collapse with TAG; type A dissection with Palmaz (treated with open repair)

Yes

6 months

1.2 yearsa 1 year

AEF, Aortoesophageal fistula; LSA, left subclavian artery; MF, Montefiore Medical Center; MS, Mount Sinai Medical Center; TEVAR, thoracic endovascular aneurysm repair; UP, University of Pittsburgh Medical Center. a Follow-up from open conversion.

This patient (patient #9) presented with symptomatic endograft collapse: complete bilateral lower extremity motor and sensory loss and bowel incontinence. He underwent an emergency redo-TEVAR by proximal extension with partial coverage of the common origin of the brachiocephalic and the LCCA (bovine arch) with resolution of the collapse and full neurologic recovery.18 However, a severe “birdbeak” was noted on completion aortography (Fig 2). The patient was advised to undergo elective open conversion with device explantation lest collapse may recur with devastating neurologic sequelas. He tolerated the procedure well 2 weeks later without any complications. Not all patients who have undergone open conversion experienced any further complications at last follow-up. No recurrent collapses have been noted after secondary TEVAR at a mean follow-up of 8.7 months. DISCUSSION This study represents the largest series of thoracic stent graft collapse, a rare but well-known complication of TEVAR. Although thoracic stent graft collapse can occur after TEVAR is performed for aneurysmal disease, it does occur

more commonly after treatment for traumatic aortic transection or spontaneous aortic dissection. This can be attributed to the difference in aortic morphology and the lack of commercially available disease-specific endografts. The use of TEVAR has emerged as the preferred method of treatment for traumatic aortic transections and complicated type B dissections. These conditions, despite the lack of endografts, meet their disease-specific considerations and have experienced improved outcomes with endovascular treatment as compared to conventional surgical repair.19-22 TEVAR can be performed quickly, safely, and with the patient under local anesthesia without systemic heparinization, which can be advantageous in patients with bleeding concerns.17 Demetriades et al22 demonstrated a significantly increased mortality rate (age-adjusted and injury severity-adjusted odds ratio of 8.4) in patients treated with open surgical repair compared with TEVAR. Clearly, TEVAR has added a valuable treatment option to the armamentarium used in the management of the spectrum of thoracic aortic pathologies. However, device-related complications may occur and often require expeditious management. Stent graft collapse in

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Fig 1. An iatrogenic aortic dissection of the ascending aorta (arrow). This was not recognized until 8 days later.

Fig 2. An additional Gore TAG endoprosthesis was placed to re-expand the collapse. However, a severe “bird-beak” is noted (arrow).

particular occurs more commonly after treatment of aortic dissection or transection,23 a finding corroborated in our review of institutional experiences. Although its true incidence is not well-defined due to poor follow-up of trauma patients in whom the majority of transection occurs, the reported incidences range from 1.4% to 19% in reported case series.10,15,16,24 Although asymptomatic in

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most cases,8,11,12,15,24,25 the collapse may pose a significant risk, namely reperfusion of the injured or dissected aortic segment or aortic occlusion, and distal end-organ malperfusion syndrome. Stent graft collapse after TEVAR may be caused by a number of anatomic- and device-related factors. It may occur with all devices, although most commonly described with the TAG endoprosthesis.14,16,26 This is not a unique problem to the Gore TAG device and has been reported with other endografts, including the Zenith TX2 (Cook Medical Inc, Bloomington, Ind) and the EndoFit (LeMaitre Vascular, Burlington, Mass). The underlying mechanism of endograft collapse is multifactorial and includes a tight aortic arch, a narrow aortic diameter,11,12,23 endograft oversizing,11,16,24,25 a “bird-beak” phenomenon,10,24 low radial force devices,11,12,23,24 material fatigue,14 and young healthy aorta.16 Muhs et al,23 in their series of six stent graft collapses, noted that no collapse occurred in patients with an aortic diameter of ⱖ23 mm, and that the sealing zone aortic diameter and the minimum aortic diameter, and not the percentage of oversizing, were predictive of stent graft collapse; they warned against the use of the TAG device in aortas smaller than 23 mm in diameter. However, the data from the current series and others indicate that the collapse can occur even when the treated aortic diameter is ⬎23 mm.12,24,25 Although excessive oversizing (even up to 90% has been reported23) has been attributed to the collapse,11,23,24 it has been shown to occur even with proper sizing.12,24-26 Canaud et al24 found acute aortic arch angulation and poor apposition of the stent graft to the inner curve of the arch to be associated with the collapse in their review of 4 cases. Neschis et al,27 in a review of 43 consecutive TEVARs for traumatic aortic transection, determined that all 4 patients who developed device-related complications (including two collapses) had the site of aortic injury within 2 cm of the LSA with the sharpest bend in the descending thoracic aorta between the LSA and the tear. The management of thoracic endograft collapse includes redo-TEVAR and open surgical repair. This can result in significant morbidity and mortality, especially in symptomatic patients. Canaud et al,24 in a review of 29 cases reported in the literature, noted a 6.8% mortality both of which occurred in symptomatic patients.15 They also noted in their series of 7 cases that all 3 patients with symptomatic collapse either died (2 patients) or suffered severe complications (renal failure, bowel ischemia, and paraparesis).15 Open thoracotomy, although definitive, can be associated with major complications even in young patients. If the collapse occurs in the early postprocedural period, which is predominantly the case, endovascular salvage is more desirable as the attendant risks of open surgery may be higher, especially in patients with multiple traumatic injuries. In addition, if the patient presents with symptoms, an endoluminal therapy may provide a quicker solution than direct open repair. The goal of endovascular repair should be to increase the radial force at the locus of collapse and improve appo-

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sition to the aortic wall. This can be achieved by placement of a large balloon-expandable stent, such as the Palmaz stent, without proximal extension into the native aorta. Simple balloon angioplasty alone is not effective; it may temporarily open the endograft, but it collapsed again after a few cardiac cycles. Deployment of a Palmaz stent into the uncovered aorta should be avoided to prevent a retrograde type A dissection or injury to the aortic arch.12 Catheterrelated or wire-related injury to the ascending aorta may also result in a type A dissection, as was observed in this series. Due precautions should be taken to avoid such an outcome. Alternatively, additional endograft placement with or without proximal extension can be performed.11,12,15,27 Proximal extension, while not always necessary, can be achieved when a sufficient neck is available. In this series, proximal extension was performed in 4 patients with coverage of the LSA in 3 patients; in 1 patient, the LSA had been covered at the initial repair. While coverage of the LSA is commonly reported and well tolerated, graft extension across the LCCA should be discouraged in young patients who have an otherwise normal life expectancy.12 When such is needed, open conversion should be strongly considered if the patient is fit. Open conversion should also be considered when additional endograft or Palmaz stent deployment leaves any concern for recurrent collapse or when late device-related complications develop. Ideally, this can be done safely when the patient has recovered fully from the initial traumatic injuries.7,25 All 3 patients in this series who underwent late conversion tolerated it well without any complications. It is also of interest to note that all these patients had late (⬎30 days) stent graft collapse. There are several limitations to this study inherent to its multicenter, retrospective design. The number of patients was small and thereby limiting. Follow-up data are also limited and thus preclude drawing any conclusions on long-term performance of redo-TEVAR for the collapse. The findings of this study relate to the Gore TAG device, as the authors have not seen any collapses with other devices as yet. As such, the observations and findings of this study may not be applicable to other devices. CONCLUSIONS Endograft collapse after TEVAR can be successfully managed by endovascular techniques in the majority of cases. Redo-TEVAR using high radial force devices should be considered the initial treatment of choice as the technical success is improved with reduced morbidity. Failure of endovascular salvage of collapsed endografts and late graftrelated complications can be effectively and safely managed with open repair without significantly added morbidity or mortality. Delayed graft collapse can occur and warrants ongoing surveillance. Late outcomes of endovascular treatment of collapse remain to be determined.

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AUTHOR CONTRIBUTIONS Conception and design: JC, PF, EL Analysis and interpretation: JC, EL, RC, PF Data collection: RT, EL, JC, RC, MM Writing the article: JC, RT, EL, RC, PF Critical revision of the article: JC, EL, RC Final approval of the article: JC Statistical analysis: Not applicable Obtained funding: Not applicable Overall responsibility: JC REFERENCES 1. Makaroun MS, Dillavou ED, Wheatley GH, Cambria RP; Gore TAG Investigators. Five-year results of endovascular treatment with the Gore TAG device compared with open repair of thoracic aortic aneurysms. J Vasc Surg 2008;47:912-8. 2. Cho JS, Haider SE, Makaroun MS. Endovascular therapy of thoracic aneurysms: Gore TAG trial results. Semin Vasc Surg 2006;19:18-24. 3. Matsumura JS, Cambria RP, Dake MD, Moore RD, Svensson LG, Snyder S; TX2 Clinical Trial Investigators. International controlled clinical trial of thoracic endovascular aneurysm repair with the Zenith TX2 endovascular graft: 1-year results. J Vasc Surg 2008;47:247-57; discussion 257. 4. Fairman RM, Criado F, Farber M, Kwolek CJ, Matsumoto A, Mehta M, et al. Pivotal results of the Medtronic Vascular Talent Thoracic Stent Graft System: the VALOR trial. J Vasc Surg 2008;48:546-54. 5. Cambria RP, Crawford RS, Cho JS, Bavaria J, Farber M, Lee WA, et al. A multicenter clinical trial of endovascular stent graft repair of acute catastrophes of the descending thoracic aorta. J Vasc Surg 2009;50:1255-64. 6. Tang GL, Tehrani HY, Usman A, Katariya K, Otero C, Perez E, et al. Reduced mortality, paraplegia, and stroke with stent graft repair of blunt aortic transections: a modern meta-analysis. J Vasc Surg 2008;47:671-5. 7. Go MR, Siegenthaler MP, Rhee RY, Gupta N, Makaroun MS, Cho JS. Physiologic coarctation of the aorta resulting from proximal protrusion of thoracic aortic stent grafts into the arch. J Vasc Surg 2008;48:1007-11. 8. Lazar HL, Varma PK, Shapira OM, Soto J, Shaw P. Endograft collapse after thoracic stent-graft repair for traumatic rupture. Ann Thorac Surg 2009;87:1582-3. 9. McCready RA, Bryant MA, Divelbiss JL, Phillips JL. Complete endograft collapse 91/2 years following endograft repair of an abdominal aortic aneurysm. Vasc Endovascular Surg 2009;43:627-30. 10. Ueda T, Fleischmann D, Dake MD, Rubin GD, Sze DY. Incomplete endograft apposition to the aortic arch: bird-beak configuration increases risk of endoleak formation after thoracic endovascular aortic repair. Radiology 2010;255:645-52. 11. Idu MM, Reekers JA, Balm R, Ponsen KJ, de Mol BA, Legemate DA. Collapse of a stent-graft following treatment of a traumatic thoracic aortic rupture. J Endovasc Ther 2005;12:503-7. 12. Steinbauer MG, Stehr A, Pfister K, Herold T, Zorger N, Töpel I, et al. Endovascular repair of proximal endograft collapse after treatment for thoracic aortic disease. J Vasc Surg 2006;43:609-12. 13. Mestres G, Maeso J, Fernandez V, Matas M. Symptomatic collapse of a thoracic aorta endoprosthesis. J Vasc Surg 2006;43:1270-3. 14. Melissano G, Tshomba Y, Civilini E, Chiesa R. Disappointing results with a new commercially available thoracic endograft. J Vasc Surg 2004;39:124-30. 15. Hinchliffe RJ, Krasznai A, Schultzekool L, Blankensteijn JD, Falkenberg M, Lönn L, et al. Observations on the failure of stent-grafts in the aortic arch. Eur J Vasc Endovasc Surg 2007;34:451-6. 16. Bandorski D, Brück M, Günther HU, Manke C. Endograft collapse after endovascular treatment for thoracic aortic disease. Cardiovasc Intervent Radiol 2010;33:492-7. 17. Go MR, Barbato JE, Dillavou ED, Gupta N, Rhee RY, Makaroun MS, et al. Thoracic endovascular aortic repair for traumatic aortic transection. J Vasc Surg 2007;46:928-33.

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23. Muhs BE, Balm R, White GH, Verhagen HJ. Anatomic factors associated with acute endograft collapse after Gore TAG treatment of thoracic aortic dissection or traumatic rupture. J Vasc Surg 2007;45:655-61. 24. Canaud L, Alric P, Desgranges P, Marzelle J, Marty-Ané C, Becquemin JP. Factors favoring stent-graft collapse after thoracic endovascular aortic repair. J Thorac Cardiovasc Surg 2010;139:1153-7. 25. Rodd CD, Desigan S, Hamady MS, Gibbs RG, Jenkins MP. Salvage options after stent collapse in the thoracic aorta. J Vasc Surg 2007;46: 780-5. 26. Eggebrecht H, Plicht B, Kahlert P, Erbel R. Intramural hematoma and penetrating ulcers: indications to endovascular treatment. Eur J Vasc Endovasc Surg 2009;38:659-65. 27. Neschis DG, Moainie S, Flinn WR, Scalea TM, Bartlett ST, Griffith BP. Endograft repair of traumatic aortic injury-a technique in evolution: a single institution’s experience. Ann Surg 2009;250:377-82. Submitted Aug 13, 2010; accepted Oct 23, 2010.

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