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Endovascular Repair of a Secondary Aortoesophageal Fistula: a Case Report and Review of the Literature
Endovascular Repair of a Secondary Aortoesophageal Fistula: a Case Report and Review of the Literature Benedict J.W. Taylor, David Stewart, Phillip West, James T. Dunn, and Paul Cisek
Secondary aortoesophageal fistula (SAEF) is a rare condition requiring expeditious diagnosis and immediate surgical correction. The prognosis for untreated patients is universally grim, while operative repair is challenging and fraught with high morbidity and mortality. Although the literature provides a selection of case reports, no general consensus exists as to the optimal surgical approach for repair of an aortoesophageal fistula. We present the case of a patient with an SAEF managed by an endovascular stent graft and staged esophageal repair. This particular case demonstrates the importance of surgical repair of the esophagus and helps define the appropriate indications for endovascular stent grafts in the setting of aortoesophageal fistula. We also include a review of the recent literature concerning SAEF, with particular emphasis on the novel use of endovascular stent grafts in this area.
CASE REPORT The patient is a 69-year-old Caucasian female who had undergone a repair of an aortic coarctation over 30 years prior to this presentation. Although the medical records of her previous surgery were unable to be located, the patient was adamant that no graft material had been used at her previous operation. She presented to a local Presented at the 23rd Annual Meeting of the Southern California Vascular Surgical Society, La Quinta, CA, May 13-15, 2005. Department of Vascular Surgery, Santa Barbara Cottage Hospital. Correspondence to: Paul Cisek, MD, E-mail: [email protected] Ann Vasc Surg 2007; 21: 167-171 DOI: 10.1016/j.avsg.2007.01.007 Ó Annals of Vascular Surgery Inc. Published online: March 9, 2007
emergency department with a 12-hour history of malaise and fever, as well as vague substernal chest discomfort that radiated toward her left neck. Initially, suspicions of an acute myocardial infarction prompted admission to the cardiology service. Aspirin and therapeutic Lovenox were administered in anticipation of angiography and percutaneous transluminal coronary angioplasty. A chest roentgenogram is shown (Fig. 1) that reveals the subtle findings of mediastinal fullness and slight rightward deviation of the trachea. A formal coronary angiography obtained within 24 hours of admission revealed normal coronary vessels and no evidence of cardiac disease. Shortly thereafter, the patient vomited 400 cc of bright red blood and became bradycardic and hypotensive. Two units of packed red blood cells, fresh frozen plasma, and a dopamine infusion were required to stabilize the patient and permit an emergent CT scan of the chest. This revealed a mediastinal soft tissue density and possibly free fluid in the mediastinum, in the area between the descending thoracic aorta and the esophagus (Fig. 2). Mural thickening of the esophageal wall was noted along with an intraluminal fluid collection in the stomach, likely representing swallowed blood. As the patient remained relatively stable, an emergent esophagoduodenoscopy was performed. A large amount of clot was noted in the middle esophagus, with an adjacent, ulcerated gelatinous mass at 25 cm. An MRI was obtained that again demonstrated areas of enhancing soft tissue density in the mediastinum between the aorta and esophagus with obvious periaortic inflammation. After a second episode of hematemesis, a thoracic aortography was obtained, which demonstrated the presence of a pseudoaneurysm just distal to the ligamentum arteriosum (Fig. 3). The patient was brought emergently to the operating room and underwent an endovascular repair of the thoracic aorta via a common femoral artery approach. An intravascular ultrasound revealed the proximal margin of the pseudoaneurysm to be just distal to the origin of the
167
168 Taylor et al.
Annals of Vascular Surgery
Fig. 1. Presenting CXR. Note mediastinal widening and rightward tracheal deviation from a secondary aortoesophageal fistula. Fig. 3. Thoracic aortic angiogram demonstrating a pseudoaneurysm just distal to the origin of the left subclavian artery.
Fig. 2. Coronal reformats of CT angiogram demonstrating soft tissue edema in the mediastinum, suggestive of an aortoesophageal fistula.
left subclavian artery. The internal diameter of the aorta at this level was between 21 and 23 mm. A 28.5-mm 3.3cm graft was deployed at this level, with a 26-mm by 3.3-cm length extension placed more proximally. A completion angiogram confirmed exclusion of the pseudoaneurysm (Fig. 4). Though the patient did not experience any further episodes of hematemesis postoperatively, she remained persistently febrile with an elevated white blood cell count. Blood cultures drawn at the time of admission grew Staphylococcus aureus and broad-spectrum antibiotics were given. Because of the clinical suspicion of ongoing mediastinitis, a repeat endoscopy was performed. This again revealed a large ulcer at approximately 25 cm, correlating to the level of the aortoesophageal fistula. A CT
Fig. 4. Intraoperative completion angiogram demonstrating complete exclusion of the pseudoaneurysm.
scan of the chest was obtained on the third postoperative day showing a fluid collection, with an air fluid interface, adjacent to the site of the repaired pseudoaneurysm. Also, the esophagus appeared adherent to the thoracic aorta. Clinically the patient’s mediastinitis and sepsis began to evolve further, and she was taken to the operating room on the fourth postoperative day for a right thoracotomy. A 3-cm esophageal ulceration was noted on exploration as well as a local area of chronic inflammation. Neither
Vol. 21, No. 2, 2007
an abscess cavity nor gross pus was encountered. The esophageal ulceration was excised and then repaired primarily with a two-layered interrupted repair using #3-0 Vicryl suture. A circumferential intercostal muscle flap was wrapped around this primary repair. The soft tissue of the posterior mediastinum was closed behind the repair to prevent the esophagus from returning to its inflamed native bed. A #2 Vicryl suture was used to ligate the esophagus 4 cm below the thoracic inlet, and a cervical loop esophagostomy was created in the left neck for complete diversion. The chest was drained with a #32 chest tube, and a feeding jejunostomy was placed through a separate midline abdominal incision. Postoperatively the patient recovered well and was discharged 9 days later on oral antibiotics. A CT scan prior to discharge was negative for residual disease. Six weeks later, she was brought back for an elective restoration of esophageal continuity. This was complicated by an empyema requiring a reopening of a portion of her thoracotomy incision, decortication, chest tube drainage, and broadspectrum antibiotics. Ultimately she was discharged without residual disease or indications for further operative treatments.
DISCUSSION The first report of AEF was described by the French physician Dubrueil1 in a case involving a sailor who died of massive hematemesis days after ingesting a beef rib splinter in 1818. Autopsy would reveal that the bone had perforated his esophagus and penetrated his descending thoracic aorta. Chiari,2 however, is responsible for a more elaborate description of the clinical presentation of AEF: distinguishing midthoracic pain, a sentinel hemorrhage event, and delayed exsanguination after a symptom-free hiatus as parts of a now classic triad. One review of AEFs by Coselli3 reveals that over two thirds of AEF patients present with chest pain, whereas two thirds manifest a herald bleed, and over 60% die within 6 hours of presentation. Overall mortality with nonsurgical therapy is total, with surgical intervention mortality ranges from 30% to 80%.3 Survival is dependent on swift diagnosis and prudent operative repair. A thorough vascular and surgical history should be acquired for any patient presenting with chest pain and hematemesis. Some authors include the presence of sepsis as an adjunctive component to Chiari’s description, as all patients with an AEF will have some degree of mediastinitis. Importantly, the hematemesis seen in AEF is characteristically bright red as compared to the darker venous hemorrhage seen in variceal bleeding.4 Chest roentgenograms may reveal a widened mediastinum, calcifications delineating a TAA and tracheal deviation. Endoscopy is invaluable in
Endovascular repair of SAEFs 169
delineating the location of the bleed and helping to establish the diagnosis of AEF. In such cases, a ‘‘cherry spot’’ clot is often seen at 20-30 cm beyond the dental arch, where the esophagus and aorta are in closest anatomical association. Computed tomography and aortography are essential in diagnosis as well as for planning the strategy of surgical approach. The former may reveal a pseudoaneurysm, fluid collection with air bubbles, a dissection, or aneurysm, whereas the later may demonstrate an active fistula tract. The causes of AEF are many fold, and may conveniently be classified into primary and secondary types. Primary AEFs are the result of intrinsic disease, such as thoracic aortic aneurysm, esophageal cancer, mediastinal tubercular infections, or incurred injury from foreign body ingestion, trauma or caustic erosions as from lye consumption.3-5 Secondary AEFs occur in the setting of prosthetic repair of aortic aneurismal disease or coarctation in 0.3% to 1.6% of patients.5 The presence of synthetic graft appears to be a risk factor, although there are cases of AEFs developing subsequent to TAA repair without the use of graft.3 Hollander4 in a comprehensive review identified 500 cases of AEF. Two hundred and fifty-six of these were caused by thoracic aneurysmal disease, 93 were associated with foreign bodies, 85 were in the setting of esophageal cancer, and 24 were deemed to be from surgical complications. Of these last 24, 15 occurred after esophagectomy operations, and seven after prosthetic grafts. Three mechanisms of pathogenesis have been suggested to explain the formation of secondary fistulas: (1) pressure necrosis of the esophageal wall secondary to a pseudoaneurysm from a leaking graft, (2) directly from pulsatile graft material in contact with the esophagus, and (3) persistent and evolving graft sepsis eroding into the adjacent esophagus.5,6 There have been reports of AEF developing from inadvertent suturing of graft to esophagus during aortic repair.6 Thus, AEF should be included in the differential diagnosis for any patient presenting with Chiari’s triad, with or without sepsis; and a known or suspected TAA, history of TAA repair, or history of primary esophageal disease. Torse et al.7 reported the first attempt at surgical repair of a primary AEF; however the patient expired from intraoperative hemorrhage. The first successful surgical repair of an AEF was performed by Yonago8 in 1969 for a patient with a prior aortic ring repair. Snyder and Crawford9 were successful with placing an in situ prosthesis as well as esophagectomy in two patients with AEF. In 1997 Oliva was successful in the endovascular repair of an
170 Taylor et al.
Annals of Vascular Surgery
Table I. Cases of endovascular repair of SAEFs #
Author
Year
Age
Sepsis
Primary procedure
Secondary procedure
Survival (months)
1
Leobon
2002
61
-
Stent graft
None
36
2 3 4
Leobon Burks Bond
2002 2001 2001
66 76 58
-
Stent graft Stent graft Stent graft
None None None
8 <1 23
AEF.10 Since that time, only 15 cases of endovascular stent grafting of AEFs have been reported, four of which have been for SAEFs. The principles of AEF repair are essentially the same regardless of approach. Foremost, hemorrhage must be controlled as soon as possible, and the fistula tract must be excluded with a definitive repair of the aorta. Second, control of the local sepsis is necessary, which usually entails esophageal repair, resection, or diversion; ultimately, if the patient survives, continuity of the esophagus can be restored with a second stage operation. An open repair requires a left thoracotomy, resection of the diseased aortic segment with an in situ graft repair, followed by esophagectomy or diversion. Da Silva11 outlined these principles in their review of 11 open AEF repairs, concluding that the best results were achieved with esophagectomy; an in situ aortic repair with a synthetic graft; and an interposed omental, pleural, or adventitia flap around the esophagus. In the presence of extensive or severe infections, extra anatomic bypass is recommended, and primary esophageal repair is discouraged because of the risk of dehiscence.11,12 All patients should receive lifelong antibiotics and should be regularly surveyed with computed tomography. Most authors argue that endovascular stents do not provide for definitive treatment of AEF without a concurrent esophageal procedure to control the concomitant sepsis that is typical in such cases.11,12,16,20 It has been suggested that an endovascular approach might serve as a bridge to thoracotomy in unstable patients, or those with comorbidities that preclude an emergent open surgery. Furthermore, an endovascular stent, in select patients, might be most appropriate as palliative procedure in the overtly moribund patient. However, recent case reports, though still few in number, have demonstrated the success of endovascular stents coupled with a second procedure to address the esophageal defect. There has also been some success with endovascular grafts being placed to treat SAEFs without
Complications
Required right iliofemoral bypass, left common femoral arterial embolectomy None Sepsis/death None
any further invasive procedures to address the esophagus (Table I).13-16 Leobon13 describes four patients, two of which had SAEFs, where endovascular stents alone were employed for AEFs. Three patients were alive and well at 8, 14, and 25 months follow-up after stent graft placement; one patient ultimately died of mediastinitis 25 months after two endovascular stent procedures spaced 23 months apart.13 Nishibe17 reports success in a primary AEF patient treated with an endovascular graft alone, with survival beyond 3 years. One SAEF was described in a review of seven aortoenteric fistulas treated with endovascular stent grafts compiled by Burks.14 One of these patients died in the postoperative period from overwhelming fungal (aspergillus) sepsis. This was a 76-year-old male with multiple comorbidities including coronary artery disease, chronic obstructive pulmonary disease, CRI, and prior TAA. Bond16 describes a case of an SAEF with an acute presentation, emergently treated with a stent graft with survival greater than 2 years. Poor results of endovascular stent grafts in the management of aortoenteric fistulas are recounted by Gonzalez-Fajardo.18 One occurred from an aortic rupture after an endovascular stent was placed for an aortoduodenal fistula. In this case, 1 week after stent placement, ensuing sepsis prompted laparotomy, bowel resection, aortic debridement, and omental wrapping of the graft. Though the patient was discharged from the hospital, the aorta ruptured 2 months later. Another occurred in the setting of an AEF, where sepsis preceded massive bleeding from an aortic rupture on the ninth postoperative day. In both cases, the authors attribute graft failure to infection. These authors advocate extreme discretion with the use of endovascular stent grafts in the presence of significant infection. Van Doorn19 provides a case of a primary AEF, managed by an endovascular graft and subsequent transhiatal esophagectomy 3 days later. This patient required reoperation at 18 months for drainage of
Vol. 21, No. 2, 2007
a symptomatic aneurysm sac hygroma. The patient survives beyond 2 years of follow-up. In another report, a 32-year-old man who presented with an AEF from a foreign body was treated with an endovascular stent and right thoracotomy with primary esophageal repair using an intercostals muscle flap. The patient had an uncomplicated postoperative course and survived past 18 months follow-up.20 This case report, along with the literature presented, supports the contention that there is a role for endovascular stent grafts in the treatment of primary and secondary AEFs. The appropriate indications for use remain to be established. Endovascular stents are an effective and expeditious means of controlling the massive hemorrhage associated with AEFs in the usual setting of sepsis and patient comorbidities. In cases of minimal local infection, or patients who are less moribund, further treatment might be unnecessary if close surveillance and broad-spectrum antibiotic coverage are strictly maintained. When there is significant or persistent infection, a definitive esophageal repair is indicated. Esophageal continuity can be restored when the patient is fully recovered from the initial acute presentation and recovered from their sepsis.
REFERENCES 1. Dubrueil. Observations sur la perforation of l’oesophage et de l’aorte thoracique par une potion d’os avale: avec der reflexions. J Univ Sci Med 1818;9:357-363. 2. Chiari H. Ueber Fremdkorpeverletzung des Oesophagus mit Aortenperforation. Berlin Klin Wschr 1914;51:7-9. 3. Coselli J, Crawford S. Primary aortoesophageal fistula from aortic aneurysm: successful surgical treatment by use of omental pedicle graft. Journal of Vascular Surgery 1990; 12:269-277. 4. Hollander J. Aortoesophageal fistula: a comprehensive review of the literature. The American Journal of Medicine 1991;91:279-287.
Endovascular repair of SAEFs 171
5. Hance K. Secondary aortoesophageal fistula after endoluminal exclusion because of thoracic aortic transection. Journal of Vascular Surgery 2003;37:886-888. 6. Pinpinos I. Secondary aortoesophageal fistula. Journal of Vascular Surgery 1997;26:144-1449. 7. Torse L, Potter RT, Laforet EG. Aorto-esophageal fistula: attempted surgical repair. Dis Chest 1962;41:680-684. 8. Yonago RH. Aortic bypass in the management of aortoesophageal fistula. Ann thoracic Surgery 1969;7:235-237. 9. Snyder DM, Craford ES. Successful treatment of primary aortaesophageal fistula resulting from aortic aneurysm. J Throacic Cardiovascular Surgery 1983;85:457-463. 10. Oliva VL. Aortoesophageal fistula: repair with transluminal placement of a thoracic aortic stent-graft. J Vasc Interv Radiology 1997;8:35-38. 11. da Silva ES. Aortoesophageal fistula caused by aneurysm of the thoracic aorta: successful surgical treament, case report, and literature review. Journal of Vascular Surgery 1999;30: 1150-1157. 12. Flores J. Aortoesophageal fistula: alternatives of treatment case report and literature review. Ann Thoracic Cardiovascular Surgery 2004;10:241-246. 13. Leobon B. Endovascular treament of thoracic aortic fistulas. Ann Thoracic Surgery 2002;74:247-249. 14. Burks J. Endovascular repair of bleeding aortoenteric fistulas: A 5 year experience. Journal of Vascular Surgery 2001;34:1055-1915. 15. Mok V. Combined endovascular stent grafting and endoscopic injection of fibrin sealant for aortoenteric fistula complicating esophagectomy. Journal of Vascular Surgery 2004;40. 16. Bond SE. Repair of secondary aortoesophageal fistula by endoluminal stent-grafting. Journal of Endovascular Therapy 2001;8:597-601. 17. Nishibe T. Successful endovascular stent-graft treatment for an aortoesophageal fistula caused by a descending thoracic aortic aneurysm: report of a case. Surgery Today 2004;34: 529-531. 18. Gonzalez-Fajardo J. Endovascular repair in the presence of aortic infection. Annals of Vascular Surgery 2005;19: 94-98. 19. Van Doorn RC. Aortoesophageal fistula secondary to mycotic thoracic aortic aneurysm: endovascular repair and transhiatal esophagectomy. Journal Endovascular Therapy 2002;9:212-217. 20. Vierhout AJ. Emergency endovascular repair of an aortoesophageal fistula caused by a foreign body. Journal of Endovascular Therapy 2005;12:129-133.
Secondary aortoesophageal fistula (SAEF) is a rare condition requiring expeditious diagnosis and immediate surgical correction. The prognosis for untreated patients is universally grim, while operative repair is challenging and fraught with high morbidity and mortality. Although the literature provides a selection of case reports, no general consensus exists as to the optimal surgical approach for repair of an aortoesophageal fistula. We present the case of a patient with an SAEF managed by an endovascular stent graft and staged esophageal repair. This particular case demonstrates the importance of surgical repair of the esophagus and helps define the appropriate indications for endovascular stent grafts in the setting of aortoesophageal fistula. We also include a review of the recent literature concerning SAEF, with particular emphasis on the novel use of endovascular stent grafts in this area.
CASE REPORT The patient is a 69-year-old Caucasian female who had undergone a repair of an aortic coarctation over 30 years prior to this presentation. Although the medical records of her previous surgery were unable to be located, the patient was adamant that no graft material had been used at her previous operation. She presented to a local Presented at the 23rd Annual Meeting of the Southern California Vascular Surgical Society, La Quinta, CA, May 13-15, 2005. Department of Vascular Surgery, Santa Barbara Cottage Hospital. Correspondence to: Paul Cisek, MD, E-mail: [email protected] Ann Vasc Surg 2007; 21: 167-171 DOI: 10.1016/j.avsg.2007.01.007 Ó Annals of Vascular Surgery Inc. Published online: March 9, 2007
emergency department with a 12-hour history of malaise and fever, as well as vague substernal chest discomfort that radiated toward her left neck. Initially, suspicions of an acute myocardial infarction prompted admission to the cardiology service. Aspirin and therapeutic Lovenox were administered in anticipation of angiography and percutaneous transluminal coronary angioplasty. A chest roentgenogram is shown (Fig. 1) that reveals the subtle findings of mediastinal fullness and slight rightward deviation of the trachea. A formal coronary angiography obtained within 24 hours of admission revealed normal coronary vessels and no evidence of cardiac disease. Shortly thereafter, the patient vomited 400 cc of bright red blood and became bradycardic and hypotensive. Two units of packed red blood cells, fresh frozen plasma, and a dopamine infusion were required to stabilize the patient and permit an emergent CT scan of the chest. This revealed a mediastinal soft tissue density and possibly free fluid in the mediastinum, in the area between the descending thoracic aorta and the esophagus (Fig. 2). Mural thickening of the esophageal wall was noted along with an intraluminal fluid collection in the stomach, likely representing swallowed blood. As the patient remained relatively stable, an emergent esophagoduodenoscopy was performed. A large amount of clot was noted in the middle esophagus, with an adjacent, ulcerated gelatinous mass at 25 cm. An MRI was obtained that again demonstrated areas of enhancing soft tissue density in the mediastinum between the aorta and esophagus with obvious periaortic inflammation. After a second episode of hematemesis, a thoracic aortography was obtained, which demonstrated the presence of a pseudoaneurysm just distal to the ligamentum arteriosum (Fig. 3). The patient was brought emergently to the operating room and underwent an endovascular repair of the thoracic aorta via a common femoral artery approach. An intravascular ultrasound revealed the proximal margin of the pseudoaneurysm to be just distal to the origin of the
167
168 Taylor et al.
Annals of Vascular Surgery
Fig. 1. Presenting CXR. Note mediastinal widening and rightward tracheal deviation from a secondary aortoesophageal fistula. Fig. 3. Thoracic aortic angiogram demonstrating a pseudoaneurysm just distal to the origin of the left subclavian artery.
Fig. 2. Coronal reformats of CT angiogram demonstrating soft tissue edema in the mediastinum, suggestive of an aortoesophageal fistula.
left subclavian artery. The internal diameter of the aorta at this level was between 21 and 23 mm. A 28.5-mm 3.3cm graft was deployed at this level, with a 26-mm by 3.3-cm length extension placed more proximally. A completion angiogram confirmed exclusion of the pseudoaneurysm (Fig. 4). Though the patient did not experience any further episodes of hematemesis postoperatively, she remained persistently febrile with an elevated white blood cell count. Blood cultures drawn at the time of admission grew Staphylococcus aureus and broad-spectrum antibiotics were given. Because of the clinical suspicion of ongoing mediastinitis, a repeat endoscopy was performed. This again revealed a large ulcer at approximately 25 cm, correlating to the level of the aortoesophageal fistula. A CT
Fig. 4. Intraoperative completion angiogram demonstrating complete exclusion of the pseudoaneurysm.
scan of the chest was obtained on the third postoperative day showing a fluid collection, with an air fluid interface, adjacent to the site of the repaired pseudoaneurysm. Also, the esophagus appeared adherent to the thoracic aorta. Clinically the patient’s mediastinitis and sepsis began to evolve further, and she was taken to the operating room on the fourth postoperative day for a right thoracotomy. A 3-cm esophageal ulceration was noted on exploration as well as a local area of chronic inflammation. Neither
Vol. 21, No. 2, 2007
an abscess cavity nor gross pus was encountered. The esophageal ulceration was excised and then repaired primarily with a two-layered interrupted repair using #3-0 Vicryl suture. A circumferential intercostal muscle flap was wrapped around this primary repair. The soft tissue of the posterior mediastinum was closed behind the repair to prevent the esophagus from returning to its inflamed native bed. A #2 Vicryl suture was used to ligate the esophagus 4 cm below the thoracic inlet, and a cervical loop esophagostomy was created in the left neck for complete diversion. The chest was drained with a #32 chest tube, and a feeding jejunostomy was placed through a separate midline abdominal incision. Postoperatively the patient recovered well and was discharged 9 days later on oral antibiotics. A CT scan prior to discharge was negative for residual disease. Six weeks later, she was brought back for an elective restoration of esophageal continuity. This was complicated by an empyema requiring a reopening of a portion of her thoracotomy incision, decortication, chest tube drainage, and broadspectrum antibiotics. Ultimately she was discharged without residual disease or indications for further operative treatments.
DISCUSSION The first report of AEF was described by the French physician Dubrueil1 in a case involving a sailor who died of massive hematemesis days after ingesting a beef rib splinter in 1818. Autopsy would reveal that the bone had perforated his esophagus and penetrated his descending thoracic aorta. Chiari,2 however, is responsible for a more elaborate description of the clinical presentation of AEF: distinguishing midthoracic pain, a sentinel hemorrhage event, and delayed exsanguination after a symptom-free hiatus as parts of a now classic triad. One review of AEFs by Coselli3 reveals that over two thirds of AEF patients present with chest pain, whereas two thirds manifest a herald bleed, and over 60% die within 6 hours of presentation. Overall mortality with nonsurgical therapy is total, with surgical intervention mortality ranges from 30% to 80%.3 Survival is dependent on swift diagnosis and prudent operative repair. A thorough vascular and surgical history should be acquired for any patient presenting with chest pain and hematemesis. Some authors include the presence of sepsis as an adjunctive component to Chiari’s description, as all patients with an AEF will have some degree of mediastinitis. Importantly, the hematemesis seen in AEF is characteristically bright red as compared to the darker venous hemorrhage seen in variceal bleeding.4 Chest roentgenograms may reveal a widened mediastinum, calcifications delineating a TAA and tracheal deviation. Endoscopy is invaluable in
Endovascular repair of SAEFs 169
delineating the location of the bleed and helping to establish the diagnosis of AEF. In such cases, a ‘‘cherry spot’’ clot is often seen at 20-30 cm beyond the dental arch, where the esophagus and aorta are in closest anatomical association. Computed tomography and aortography are essential in diagnosis as well as for planning the strategy of surgical approach. The former may reveal a pseudoaneurysm, fluid collection with air bubbles, a dissection, or aneurysm, whereas the later may demonstrate an active fistula tract. The causes of AEF are many fold, and may conveniently be classified into primary and secondary types. Primary AEFs are the result of intrinsic disease, such as thoracic aortic aneurysm, esophageal cancer, mediastinal tubercular infections, or incurred injury from foreign body ingestion, trauma or caustic erosions as from lye consumption.3-5 Secondary AEFs occur in the setting of prosthetic repair of aortic aneurismal disease or coarctation in 0.3% to 1.6% of patients.5 The presence of synthetic graft appears to be a risk factor, although there are cases of AEFs developing subsequent to TAA repair without the use of graft.3 Hollander4 in a comprehensive review identified 500 cases of AEF. Two hundred and fifty-six of these were caused by thoracic aneurysmal disease, 93 were associated with foreign bodies, 85 were in the setting of esophageal cancer, and 24 were deemed to be from surgical complications. Of these last 24, 15 occurred after esophagectomy operations, and seven after prosthetic grafts. Three mechanisms of pathogenesis have been suggested to explain the formation of secondary fistulas: (1) pressure necrosis of the esophageal wall secondary to a pseudoaneurysm from a leaking graft, (2) directly from pulsatile graft material in contact with the esophagus, and (3) persistent and evolving graft sepsis eroding into the adjacent esophagus.5,6 There have been reports of AEF developing from inadvertent suturing of graft to esophagus during aortic repair.6 Thus, AEF should be included in the differential diagnosis for any patient presenting with Chiari’s triad, with or without sepsis; and a known or suspected TAA, history of TAA repair, or history of primary esophageal disease. Torse et al.7 reported the first attempt at surgical repair of a primary AEF; however the patient expired from intraoperative hemorrhage. The first successful surgical repair of an AEF was performed by Yonago8 in 1969 for a patient with a prior aortic ring repair. Snyder and Crawford9 were successful with placing an in situ prosthesis as well as esophagectomy in two patients with AEF. In 1997 Oliva was successful in the endovascular repair of an
170 Taylor et al.
Annals of Vascular Surgery
Table I. Cases of endovascular repair of SAEFs #
Author
Year
Age
Sepsis
Primary procedure
Secondary procedure
Survival (months)
1
Leobon
2002
61
-
Stent graft
None
36
2 3 4
Leobon Burks Bond
2002 2001 2001
66 76 58
-
Stent graft Stent graft Stent graft
None None None
8 <1 23
AEF.10 Since that time, only 15 cases of endovascular stent grafting of AEFs have been reported, four of which have been for SAEFs. The principles of AEF repair are essentially the same regardless of approach. Foremost, hemorrhage must be controlled as soon as possible, and the fistula tract must be excluded with a definitive repair of the aorta. Second, control of the local sepsis is necessary, which usually entails esophageal repair, resection, or diversion; ultimately, if the patient survives, continuity of the esophagus can be restored with a second stage operation. An open repair requires a left thoracotomy, resection of the diseased aortic segment with an in situ graft repair, followed by esophagectomy or diversion. Da Silva11 outlined these principles in their review of 11 open AEF repairs, concluding that the best results were achieved with esophagectomy; an in situ aortic repair with a synthetic graft; and an interposed omental, pleural, or adventitia flap around the esophagus. In the presence of extensive or severe infections, extra anatomic bypass is recommended, and primary esophageal repair is discouraged because of the risk of dehiscence.11,12 All patients should receive lifelong antibiotics and should be regularly surveyed with computed tomography. Most authors argue that endovascular stents do not provide for definitive treatment of AEF without a concurrent esophageal procedure to control the concomitant sepsis that is typical in such cases.11,12,16,20 It has been suggested that an endovascular approach might serve as a bridge to thoracotomy in unstable patients, or those with comorbidities that preclude an emergent open surgery. Furthermore, an endovascular stent, in select patients, might be most appropriate as palliative procedure in the overtly moribund patient. However, recent case reports, though still few in number, have demonstrated the success of endovascular stents coupled with a second procedure to address the esophageal defect. There has also been some success with endovascular grafts being placed to treat SAEFs without
Complications
Required right iliofemoral bypass, left common femoral arterial embolectomy None Sepsis/death None
any further invasive procedures to address the esophagus (Table I).13-16 Leobon13 describes four patients, two of which had SAEFs, where endovascular stents alone were employed for AEFs. Three patients were alive and well at 8, 14, and 25 months follow-up after stent graft placement; one patient ultimately died of mediastinitis 25 months after two endovascular stent procedures spaced 23 months apart.13 Nishibe17 reports success in a primary AEF patient treated with an endovascular graft alone, with survival beyond 3 years. One SAEF was described in a review of seven aortoenteric fistulas treated with endovascular stent grafts compiled by Burks.14 One of these patients died in the postoperative period from overwhelming fungal (aspergillus) sepsis. This was a 76-year-old male with multiple comorbidities including coronary artery disease, chronic obstructive pulmonary disease, CRI, and prior TAA. Bond16 describes a case of an SAEF with an acute presentation, emergently treated with a stent graft with survival greater than 2 years. Poor results of endovascular stent grafts in the management of aortoenteric fistulas are recounted by Gonzalez-Fajardo.18 One occurred from an aortic rupture after an endovascular stent was placed for an aortoduodenal fistula. In this case, 1 week after stent placement, ensuing sepsis prompted laparotomy, bowel resection, aortic debridement, and omental wrapping of the graft. Though the patient was discharged from the hospital, the aorta ruptured 2 months later. Another occurred in the setting of an AEF, where sepsis preceded massive bleeding from an aortic rupture on the ninth postoperative day. In both cases, the authors attribute graft failure to infection. These authors advocate extreme discretion with the use of endovascular stent grafts in the presence of significant infection. Van Doorn19 provides a case of a primary AEF, managed by an endovascular graft and subsequent transhiatal esophagectomy 3 days later. This patient required reoperation at 18 months for drainage of
Vol. 21, No. 2, 2007
a symptomatic aneurysm sac hygroma. The patient survives beyond 2 years of follow-up. In another report, a 32-year-old man who presented with an AEF from a foreign body was treated with an endovascular stent and right thoracotomy with primary esophageal repair using an intercostals muscle flap. The patient had an uncomplicated postoperative course and survived past 18 months follow-up.20 This case report, along with the literature presented, supports the contention that there is a role for endovascular stent grafts in the treatment of primary and secondary AEFs. The appropriate indications for use remain to be established. Endovascular stents are an effective and expeditious means of controlling the massive hemorrhage associated with AEFs in the usual setting of sepsis and patient comorbidities. In cases of minimal local infection, or patients who are less moribund, further treatment might be unnecessary if close surveillance and broad-spectrum antibiotic coverage are strictly maintained. When there is significant or persistent infection, a definitive esophageal repair is indicated. Esophageal continuity can be restored when the patient is fully recovered from the initial acute presentation and recovered from their sepsis.
REFERENCES 1. Dubrueil. Observations sur la perforation of l’oesophage et de l’aorte thoracique par une potion d’os avale: avec der reflexions. J Univ Sci Med 1818;9:357-363. 2. Chiari H. Ueber Fremdkorpeverletzung des Oesophagus mit Aortenperforation. Berlin Klin Wschr 1914;51:7-9. 3. Coselli J, Crawford S. Primary aortoesophageal fistula from aortic aneurysm: successful surgical treatment by use of omental pedicle graft. Journal of Vascular Surgery 1990; 12:269-277. 4. Hollander J. Aortoesophageal fistula: a comprehensive review of the literature. The American Journal of Medicine 1991;91:279-287.
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5. Hance K. Secondary aortoesophageal fistula after endoluminal exclusion because of thoracic aortic transection. Journal of Vascular Surgery 2003;37:886-888. 6. Pinpinos I. Secondary aortoesophageal fistula. Journal of Vascular Surgery 1997;26:144-1449. 7. Torse L, Potter RT, Laforet EG. Aorto-esophageal fistula: attempted surgical repair. Dis Chest 1962;41:680-684. 8. Yonago RH. Aortic bypass in the management of aortoesophageal fistula. Ann thoracic Surgery 1969;7:235-237. 9. Snyder DM, Craford ES. Successful treatment of primary aortaesophageal fistula resulting from aortic aneurysm. J Throacic Cardiovascular Surgery 1983;85:457-463. 10. Oliva VL. Aortoesophageal fistula: repair with transluminal placement of a thoracic aortic stent-graft. J Vasc Interv Radiology 1997;8:35-38. 11. da Silva ES. Aortoesophageal fistula caused by aneurysm of the thoracic aorta: successful surgical treament, case report, and literature review. Journal of Vascular Surgery 1999;30: 1150-1157. 12. Flores J. Aortoesophageal fistula: alternatives of treatment case report and literature review. Ann Thoracic Cardiovascular Surgery 2004;10:241-246. 13. Leobon B. Endovascular treament of thoracic aortic fistulas. Ann Thoracic Surgery 2002;74:247-249. 14. Burks J. Endovascular repair of bleeding aortoenteric fistulas: A 5 year experience. Journal of Vascular Surgery 2001;34:1055-1915. 15. Mok V. Combined endovascular stent grafting and endoscopic injection of fibrin sealant for aortoenteric fistula complicating esophagectomy. Journal of Vascular Surgery 2004;40. 16. Bond SE. Repair of secondary aortoesophageal fistula by endoluminal stent-grafting. Journal of Endovascular Therapy 2001;8:597-601. 17. Nishibe T. Successful endovascular stent-graft treatment for an aortoesophageal fistula caused by a descending thoracic aortic aneurysm: report of a case. Surgery Today 2004;34: 529-531. 18. Gonzalez-Fajardo J. Endovascular repair in the presence of aortic infection. Annals of Vascular Surgery 2005;19: 94-98. 19. Van Doorn RC. Aortoesophageal fistula secondary to mycotic thoracic aortic aneurysm: endovascular repair and transhiatal esophagectomy. Journal Endovascular Therapy 2002;9:212-217. 20. Vierhout AJ. Emergency endovascular repair of an aortoesophageal fistula caused by a foreign body. Journal of Endovascular Therapy 2005;12:129-133.