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Original Articles: Adult Cardiac

Endovascular Stenting for Traumatic Aortic Injury: An Emerging New Standard of Care

^a Division of Cardiac Surgery, University of Maryland School of Medicine, Baltimore, Maryland
^b Division of Vascular Surgery, University of Maryland School of Medicine, Baltimore, Maryland
^c R. Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland

Accepted for publication January 28, 2008.

^_* Address correspondence to Dr Moainie, Division of Cardiac Surgery, N4W94, 22 S Greene St, Baltimore, MD 21201 (Email: smoainie{at}smail.umaryland.edu).

Presented at the Forty-third Annual Meeting of The Society of Thoracic Surgeons, San Diego, CA, Jan 29–31, 2007.

This article has been selected for the open discussion forum on the CTSNet Web Site: http://www.ctsnet.org/sections/newsandviews/discussions/index.html

 

	Abstract

Top Abstract Introduction Patients and Methods Results Comment Discussion References

 
Background: Thoracic aortic injury remains a leading cause of death after blunt trauma. Thoracic aortic stents have the potential to treat aortic tears using a less invasive approach. We have accumulated the largest series of patients treated with blunt thoracic aortic injury over a 2-year period.

Methods: From July 2005 to present, 26 patients presenting with blunt aortic injury were treated with thoracic aortic endografting; these patients were retrospectively compared with the prior 26 patients presenting with similar aortic injury who were treated by open surgical repair. A Severity Characterization of Trauma score calculated for each patient predicts mortality based on severity of injury and degree of physiologic derangement on presentation.

Results: Patients treated with endografting had a significantly shorter length of stay, less intraoperative blood loss, decreased 24-hour blood transfusion, and lower incidence of postoperative tracheostomy compared with patients undergoing open repair. Survival in both groups was similar despite a trend toward higher injury severity among patients treated with endografting.

Conclusions: This early experience suggests that aortic endografting may provide a safe and efficient treatment of aortic tears that cardiac surgeons can be successful in employing.

Thoracic aortic trauma remains a leading cause of mortality after blunt trauma. In trauma patients incurring aortic injury, between 20% and 50% have associated injuries [1]. The high incidence of concomitant injuries in patients with traumatic aortic rupture makes them poorly suited to undergo a major operative procedure involving a thoracotomy, single-lung ventilation, and cardiopulmonary bypass for aortic reconstruction. Operative mortality for conventional repair of traumatic aortic rupture ranges from 0% to 54%, with postoperative paraplegia incidence ranging from 0% to 36% [2–6].

Endovascular stent grafts for the thoracic aorta provide an exciting new alternative to the conventional approach for treating traumatic aortic rupture. Numerous investigators have demonstrated successful repair of traumatic aortic rupture using endovascular repair techniques [7–13]. The use of endoaortic stents to treat traumatic aortic rupture has a number of theoretical advantages over conventional surgery. By avoiding the need for thoracotomy and single-lung ventilation in a multiple-trauma patient, the risk of postoperative pulmonary complications should be reduced. Additionally, the minimally invasive approach used in the endovascular repair should decrease the need for blood transfusion.

The commercial availability of stent grafts for use in the thoracic aorta in 2005 enabled our group to investigate the hypothesis that treatment of traumatic aortic rupture using an endovascular approach would result in improved patient outcomes. The low procedural risk of endoaortic stenting demonstrated by other investigators combined with the theoretical advantages of a minimally invasive surgical treatment convinced us to begin using endovascular stenting as our preferred treatment strategy for all patients presenting with traumatic aortic rupture since July 2005 [7–13]. Over a 24-month period, we have accumulated a relatively large series of 26 patients, which is to our knowledge the largest single-center series of traumatic aortic rupture endografts accumulated over a 2-year period. In the present report, we retrospectively compare our experience with endovascular repair for traumatic aortic rupture with that of our conventional surgical repair.

	Patients and Methods

Top Abstract Introduction Patients and Methods Results Comment Discussion References

 
Patients
From July 2005 to July 2007, 27 patients presented to the R. Adams Cowley Shock Trauma Center with traumatic aortic rupture secondary to blunt force trauma, 26 of whom were treated with endovascular thoracic aortic stent grafts. One patient, a 21-year-old man who sustained a traumatic aortic rupture after a fall, was found on initial evaluation to have a right-sided aortic arch and aberrant arch vessel anatomy. This patient was treated with open repair because it was thought that his anatomic anomalies would not permit adequate landing of an endograft without compromising the arch vessels. Mechanisms of injury in the 26 patients treated with endovascular stenting were automobile accident in 20 patients (77.0%), fall in 2 patients (7.7%), motorcycle collision in 3 patients (11.5%), and light-weight aircraft failure in 1 patient (3.8%). Informed consent for surgical procedures performed was obtained in all cases, either from the patients themselves or from the patient's relatives. The University of Maryland Institutional Review Board granted waiver of consent and waiver of the Health Insurance Portablility and Accountablility Act for this study on January 24, 2008.

There were 19 males with a mean age of 33.0 ± 12.2 years (range, 17 to 88) and 7 females with mean age of 55.0 ± 11.5 years (range, 52 to 78) at the time of presentation. This group was compared in retrospective fashion with a group of 26 consecutive patients undergoing conventional surgical repair of traumatic aortic rupture over the preceding 42-month period. Mechanism of injury in patients treated with open repair was motor vehicle collision in 22 patients (84.6%), motorcycle accident in 2 patients (7.7%), and fall in 2 patients (7.7%). The patients in the open repair group included 19 males with mean age of 32.3 ± 14.3 years (range, 16 to 63) and 7 females with mean age of 36.6 ± 17.1 years (range, 21 to 72). Indication for surgery in both groups of patients was any evidence of aortic trauma defined as aortic pseudoaneurysm, intimal disruption, or adventitial hematoma, as identified by high-resolution computed tomography with 3-mm sections through the thoracic aorta. Admission computed tomography was used to measure aortic diameter by averaging the diameter of the uninjured aorta 1 cm proximal and distal to the level of injury. The common femoral artery diameter was measured at the level of the inguinal ligament.

Methods
All endovascular procedures were performed under general anesthesia in an angiographic operating room with fixed fluoroscopic equipment (Toshiba Medical Systems, Tustin, California). Preoperative computed tomography imaging with three-dimensional reconstruction was utilized in all cases to guide device selection (Fig 1). Mean aortic diameter in patients treated with endografting was 22.7 ± 2.7 cm (range, 17.9 to 28.2 cm). Our strategy was to limit any upsizing of the selected endoprosthesis to no more than 10% of the aortic diameter. Nine patients underwent endovascular repair using the Gore TAG stent graft (W.L. Gore & Assoc, Flagstaff, Arizona), and 17 patients underwent repair using proximal extension cuffs from the Excluder AAA endoprosthesis (W.L. Gore & Assoc; Fig 2). The Excluder device was used in patients with an aortic diameter less than 26 cm, as a TAG graft appropriate for this size is not available.

View larger version (82K): [in this window] [in a new window]   Fig 1. (A) Computed tomography scan demonstrating aortic disruption in a patient presenting after a motor vehicle collision. (B) Three-dimensional reconstruction of the computed tomography scan shown in (A) demonstrating the site of aortic injury in relation to the aortic arch.

View larger version (68K): [in this window] [in a new window]   Fig 2. (A) Pretreatment angiogram illustrating aortic rupture. (B) Completion angiogram demonstrating successful treatment of aortic rupture shown in (A), with two 26 mm x 3.3 cm Gore Excluder cuffs (W. L. Gore & Assoc, Flagstaff, Arizona).

Characterization of Injury
Patients' associated injuries at the time of presentation were determined by reviewing the admission examination of the attending trauma surgeon as well as the admitting radiography as interpreted by an independent attending radiologist. Hepatic, splenic, or intracranial trauma are defined as any evidence of injury identified on the admission computed tomography scan. Likewise, patients were characterized as having pulmonary contusion if any radiographic signs of contusion were identified by the attending radiologist interpretation of the admission computed tomography scan.

A Severity Characterization of Trauma (ASCOT) score is a physiologic and anatomic characterization of injury severity that uses Glasgow Coma Scale, Abbreviated Injury Scale, age, systolic blood pressure, and respiratory rate on arrival to the trauma center to further define injury severity and calculate probability of survival [15]. The ASCOT values were calculated using a logistic function calculation, as previously described by Champion and coworkers [15]. The calculated probability of survival based on the ASCOT score has been demonstrated to be the most accurate predictor of survival after blunt force trauma [16–18].

Statistics
Continuous variables are reported as mean ± SD. Differences between groups are compared by two-way analysis of variance (Microsoft Corporation, Redmond, Washington). Differences in length of stay, need for tracheostomy, and units of blood transfused were compared using the Mann-Whitney test.

	Results

Top Abstract Introduction Patients and Methods Results Comment Discussion References

 
Endovascular repair was successfully performed in 24 patients (92.3%). Two patients (7.7%) required reoperation, one for type I endoleak and 1 for delayed graft collapse (requiring open operation with graft retrieval and interposition graft placement). The patient with a type I endoleak was treated with repeat endovascular repair with placement of an additional endograft at the proximal landing zone, extending the proximal landing zone to cover the previously uncovered left subclavian artery, resulting in resolution of the endoleak. The observed graft collapse was most likely secondary to inadequate apposition of the stent along the inner curve of the aortic arch, resulting in graft collapse. No adverse sequelae were observed in the 6 patients (23.0%) requiring left subclavian artery exclusion for proper placement of the aortic endograft.

A comparison of results between patients treated with endovascular stent grafting and open surgery is summarized in Table 1. Interval from presentation to surgery was similar for patients treated with open and endovascular surgery, averaging 35.0 and 38.8 hours, respectively, and no deaths occurred in either group due to aortic rupture awaiting intervention. Early in our experience, our ability to perform emergent endovascular stenting was limited by a shortage of staff with adequate expertise in endovascular techniques and also limited immediate stent graft availability, thus leading to an increase in interval to surgery in patients treated with endografting. Delays in therapy for patients treated with open surgery were due to patients being deemed unsuitable for open surgical therapy owing to concerns about inability to tolerate single-lung ventilation or anticoagulation. The growth of our endovascular program has eliminated our earlier limitation to perform emergent endovascular interventions, and we anticipate that an additional advantage of endovascular therapy for future patients will be a decreased interval to surgery, resulting in a further decrease in length of hospitalization.

Perioperative blood loss was 2080.8 mL (± 2036.0 mL) in patients treated with open surgery as compared with 150.0 mL (± 68.0 mL) in patients treated with endovascular stenting (p < 0.00001). The decreased perioperative blood loss translated into a decreased need for perioperative blood transfusion, as demonstrated in Table 2. Need for postoperative tracheostomy, as determined by an independent critical care team caring for the patient, was used as a marker of prolonged mechanical ventilation. Despite a larger number of patients treated with endoaortic stenting identified as sustaining pulmonary contusion on admission as compared with patients treated with open surgery (46% versus 27%, respectively), only 3 patients (12%) treated with endografting required postoperative tracheostomy, as compared with 10 patients (40%) surviving open repair requiring tracheostomy. Length of stay was also found to be shorter among patients treated with an endovascular approach as compared with conventional surgery.

	Comment

Top Abstract Introduction Patients and Methods Results Comment Discussion References

A weakness of the present study is the limited number of patients and short-term follow-up; these early findings do, however, suggest areas for future investigation. The identical patient survival between patients treated with endografting and patients treated with open surgery, when evaluated in the context of increased intracranial and pulmonary trauma, and a trend toward lower predicted survival for patients treated with endografting lead us to believe that endoaortic stent grafting may have a favorable impact on survival in the most severely injured patients. Eight patients (31%) treated with endografting had an ASCOT-predicted mortality of greater than 50% (of whom only 2 died). In the group of patients treated with conventional surgery, only 5 patients (19%) had an ASCOT-predicted mortality greater than 50% (of whom 1 died). We plan continued investigation to determine impact on survival of endovascular treatment of traumatic aortic rupture in patients with high predicted mortality.

Since their first description in 1991, endovascular aortic stent grafts have dramatically altered the treatment of aortic aneurismal disease [21, 22]. The availability of endoaortic stent grafts provides an exciting new alternative to treating patients with traumatic aortic rupture. Endovascular techniques are ideally suited for the treatment of these injuries for a number of reasons. The use of endoluminally delivered stents eliminates the need for thoracotomy and single-lung ventilation and the ensuing pulmonary complications that occur with this surgical approach. The decreased requirement for tracheostomy observed in our group of patients treated with endoaortic stenting clearly demonstrates that these patients had decreased postoperative mechanical ventilation requirements as compared with patients undergoing conventional surgical repair. That 3 of the 4 deaths occurring among patients treated with open surgery were due to respiratory failure, as compared with no patient deaths secondary to respiratory complications in the endovascular therapy group, is further evidence of the significant decrease in pulmonary injury with endovascular therapy. The decreased incidence of pulmonary dysfunction among patients treated with endoluminal stenting along with a significantly larger proportion of these patients suffering pulmonary contusion supports the notion that avoiding thoracotomy and cardiopulmonary bypass significantly decreases postoperative morbidity. The combination of a major thoracotomy and cardiopulmonary bypass results in significantly greater blood loss, and thus higher blood transfusion requirements, for patients undergoing open surgery for traumatic aortic rupture than for patients having endoluminal stenting.

Additional theoretical benefits of endovascular treatment of traumatic aortic rupture exist that were not directly evaluated in this study. Because endovascular repair of traumatic aortic rupture does not involve an aortotomy, there is no need for the degree of aggressive blood pressure control postoperatively as there is for patients undergoing open repair. After endovascular repair of traumatic aortic rupture, we routinely allow the patient's blood pressure to remain at baseline levels. In contrast, patients treated with open repair are maintained with systolic blood pressures in the 100 to 120 mm Hg range to protect the aortic suture line. We speculate that the difference in antihypertensive management in the two groups of patients may lead to improved cerebral and other end-organ perfusion pressures in patients treated with endovascular grafts. Further, the minimally invasive approach certainly results in decreased postoperative discomfort, as suggested by the shorter length of stay of patients treated with endoaortic stenting. It is reasonable to assume that the faster recovery period translates into a more rapid return to work of patients treated with endovascular stenting, thus diminishing the socioeconomic impact of trauma.

The development of endovascular techniques for thoracic aortic trauma presents a minimally invasive alternative to treating patients with traumatic aortic rupture. Although the long-term outcome in patients treated with endoaortic stent grafts has yet to be determined, our early experience suggests that this new technique provides a favorable alternative to conventional open surgery for the treatment of thoracic aortic trauma.

	Discussion

Top Abstract Introduction Patients and Methods Results Comment Discussion References

 
DR JOSEPH S. COSELLI (Houston, TX): Congratulations on an excellent and concise presentation. I think this is important work from the standpoint that it continues to push this evolving technology in areas of off-label use, providing impetus for the industry to continue to evolve and develop the devices necessary to implement this technology. Additionally, this may be quite valuable in the management of patients in institutions and situations where open operations for traumatic lesions of the proximal thoracic aorta for trauma are carried out in the low single digits with frequently poor results. I do have a few questions with regard to the presentation and hopefully can elucidate some additional issues.

These include, was cerebrospinal fluid drainage used in either of the two groups? What was the time frame between the incidence of injury and the time of intervention for the two groups, and were they similar? How many stent grafts were used doing these repairs, and how much of the aorta was actually covered up? There is no mention of stroke, paraplegia, and paraparesis in the manuscript, and I think this should be elucidated.

The size of the graft is important. Many of these patients have relatively small aortas, and oversizing can be an issue, and at least in 1 of the patients, oversizing may have been the cause of collapse of the stent graft, which had to be removed. Further, tracheostomy as a variable can be prone to bias and subjectivity. So what were the criteria used for the placement of tracheostomy and were these similar for the two groups? And then finally, access—particularly in these still larger sizes that are available to us in the treatment of these patients, and the fact that in this series there were some older patients—were iliac conduit accesses required in any of these individuals? Thank you.

DR MOAINIE: Thank you, Dr Coselli. In response to your questions, first, cerebrospinal fluid drainage was not used in either group of patients, mainly because there was short segment coverage that was used in the endografting patients and focal repair was done in the open patients. So neither one received cerebrospinal fluid drainage.

Your second question in terms of timing of intervention, timing of intervention was similar in both groups of patients. Approximately 80% of patients had repair done within the first 24 hours of presentation, and the other 20% had delayed repair because of head injuries.

In terms of length of aorta that was covered, the patients received either a Gore TAG graft or the Gore Excluder proximal extension cuffs grafts, which are 3.3-cm grafts. The average length of aorta that was covered was about 8 cm. With those who received the Excluder cuffs grafts, we used an average of three grafts per patient in those groups, and those who received the Gore TAG grafts received one graft, on average, and that was a 10-cm graft.

There were no strokes or paraplegia in either group other than the one brain death that I mentioned; however, that was a patient who had no neurologic function preoperatively either, and there was no evidence of a change in the head computed tomography scan preoperatively or postoperatively.

Our indications for tracheostomy were an anticipated need for prolonged mechanical ventilation as determined by an independent assessment by a critical care physician. Thank you, sir.

	References

Top Abstract Introduction Patients and Methods Results Comment Discussion References

 

1. Cook J, Salerno C, Krishnadasan B, Nicholls S, Meissner M, Karmy-Jones R. The effect of changing presentation and management on the outcome of blunt rupture of the thoracic aorta J Thorac Cardiovasc Surg 2006;131:594-600.[Abstract/Free Full Text]
2. von Oppell UO, Dunne TT, De Groot MK, Zilla P. Traumatic aortic rupture: twenty-year metaanalysis of mortality and risk of paraplegia Ann Thorac Surg 1994;58:585-593.[Abstract]
3. Turney SZ, Attar S, Ayella R, Cowley RA, McLaughlin J. Traumatic rupture of the aorta. A five-year experience. J Thorac Cardiovasc Surg 1976;72:727-734.[Abstract]
4. Smith RS, Chang FC. Traumatic rupture of the aorta: still a lethal injury Am J Surg 1986;152:660-663.[Medline]
5. Fabian TC, Richardson JD, Croce MA, et al. Prospective study of blunt aortic injury: Multicenter Trial of the American Association for the Surgery of Trauma J Trauma 1997;42:374-380discussion 380–3.[Medline]
6. Gammie JS, Shah AS, Hattler BG, et al. Traumatic aortic rupture: diagnosis and management[see comment] Ann Thorac Surg 1998;66:1295-1300.[Abstract/Free Full Text]
7. Iannelli G, Piscione F, Di Tommaso L, Monaco M, Chiariello M, Spampinato N. Thoracic aortic emergencies: impact of endovascular surgery Ann Thorac Surg 2004;77:591-596.[Abstract/Free Full Text]
8. Agostinelli A, Saccani S, Borrello B, Nicolini F, Larini P, Gherli T. Immediate endovascular treatment of blunt aortic injury: our therapeutic strategy J Thorac Cardiovasc Surg 2006;131:1053-1057.[Abstract/Free Full Text]
9. Dunham MB, Zygun D, Petrasek P, Kortbeek JB, Karmy-Jones R, Moore RD. Endovascular stent grafts for acute blunt aortic injury J Trauma 2004;56:1173-1178.[Medline]
10. Fujikawa T, Yukioka T, Ishimaru S, et al. Endovascular stent grafting for the treatment of blunt thoracic aortic injury J Trauma 2001;50:223-229.[Medline]
11. Lebl DR, Dicker RA, Spain DA, Brundage SI. Dramatic shift in the primary management of traumatic thoracic aortic rupture Arch Surg 2006;141:177-180.[Abstract/Free Full Text]
12. Nio D, Vos PM, de Mol BA, Ponsen KJ, Reekers JA, Balm R. Emergency endovascular treatment of thoracic aortic rupture in three accident victims with multiple injuries J Endovasc Ther 2002;9(Suppl 2):II60-II66.[Medline]
13. Orend KH, Pamler R, Kapfer X, Liewald F, Görich J, Sunder-Plassmann L. Endovascular repair of traumatic descending aortic transection J Endovasc Ther 2002;9:573-578.[Medline]
14. Cardarelli MG, McLaughlin JS, Downing SW, Brown JM, Attar S, Griffith BP. Management of traumatic aortic rupture: a 30-year experience Ann Surg 2002;236:465-470.[Medline]
15. Champion HR, Copes WS, Sacco WJ, et al. A new characterization of injury severity J Trauma 1990;30:539-546.[Medline]
16. Champion HR, Copes WS, Sacco WJ, et al. Improved predictions from a severity characterization of trauma (ASCOT) over Trauma and Injury Severity Score (TRISS): results of an independent evaluation J Trauma 1996;40:42-49.[Medline]
17. Markle J, Cayten CG, Byrne DW, Moy F, Murphy JG. Comparison between TRISS and ASCOT methods in controlling for injury severity J Trauma 1992;33:326-332.[Medline]
18. Gabbe BJ, et al. Predictors of mortality, length of stay and discharge destination in blunt trauma Aust NZ J Surg 2005;75:650-656.
19. Ochsner Jr MG, Hoffman AP, DiPasquale D, et al. Associated aortic rupture-pelvic fracture: an alert for orthopedic and general surgeons J Trauma 1992;33:429-434.[Medline]
20. McGwin Jr G, Reiff DA, Moran SG, Rue 3rd LW. Incidence and characteristics of motor vehicle collision-related blunt thoracic aortic injury according to age J Trauma 2002;52:859-866.[Medline]
21. Parodi JC, Palmaz JC, Barone HD. Transfemoral intraluminal graft implantation for abdominal aortic aneurysms Ann Vasc Surg 1991;5:491-499.[Medline]
22. Volodos NL, et al. Clinical experience of the use of self-fixing synthetic prostheses for remote endoprosthetics of the thoracic and the abdominal aorta and iliac arteries through the femoral artery and as intraoperative endoprosthesis for aorta reconstruction Vasa 1991;33(Suppl):93-95.

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This Article Abstract Full Text (PDF) Online Discussion (Adult) Online Discussion (Pediatric) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Sina L. Moainie James S. Gammie James M. Brown Robert S. Poston Bartley P. Griffith Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Moainie, S. L. Articles by Griffith, B. P. Search for Related Content PubMed PubMed Citation Articles by Moainie, S. L. Articles by Griffith, B. P. Related Collections Great vessels