Aortic stent-graft infection due to a presumed aortoenteric fistula

Secondary Aorto-enteric Fistula and Type II Endoleak Five Years after Endovascular Abdominal Aortic Aneurysm Repair

Introduction

Secondary aorto-enteric fistula (AEF) after endovascular abdominal aortic aneurysm repair (EVAR) is a rare but potentially fatal disease. The aetiology and mechanisms are unclear. This study presents a patient who developed secondary AEF and type II endoleak five years after EVAR.

Case

A 73 year old man underwent successful EVAR with a bifurcated aortic stent graft for a 5.5 cm infrarenal abdominal aortic aneurysm. The aneurysm sac showed no change in size for three years, then shrank 20 mm to 3.5 cm by five years. After five years and eight months, the patient presented with fever and back pain. Enhanced CT demonstrated enlargement of the aneurysm sac, type II endoleak from the third and fourth right lumbar arteries, and air around the stent graft. An emergency operation was performed. The infected stent graft was removed by pushing up the stent graft to release the hooks from the wall of the aorta. A small fistula resembling a fish mouth measuring 1×1 cm was observed in the third part of the duodenum. The fistula was closed by direct suture, and in situ reconstruction was performed with an 18×9 mm standard polyethylene terephthalate graft. Culture of the explanted stent graft grew enterobacter. Intravenous antibiotic therapy was continued for six weeks and was stopped after confirming no recurrence of infection with computed tomography and laboratory testing. Two years later, there has been no recurrence of infection.

Conclusion

Long term surveillance is critical because AEF can occur even after initially successful EVAR.

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Secondary aorto-enteric fistula post endovascular abdominal aortic aneurysm repair can occur in the late phase of follow up.

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Staged omentopexy may be beneficial for prevention of recurrent infection.

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Type II endoleak can affect the development of secondary aorto-enteric fistula.

Editor's Choice - Management of Secondary Aorto-enteric and Other Abdominal Arterio-enteric Fistulas: A Review and Pooled Data Analysis

OBJECTIVES

To compare management strategies for secondary abdominal arterio-enteric fistulas (AEFs).

METHODS

This study is a review and pooled data analysis. Medline and Scopus databases were searched for studies published between 1999 and 2015. Particular emphasis was given to short- and long-term outcomes in relation to AEF repair type.

RESULTS

Two hundred and sixteen publications were retrieved, reporting on 823 patients. In-hospital mortality was 30.7%. Open surgery had higher in-hospital mortality (246/725, 33.9%), than endovascular methods (7/98, 7.1%, p < .001, OR 6.7, 95% CI 3-14.7, including staged endovascular to open surgery, 0/13, 0%). In-hospital mortality after graft removal/extra-anatomical bypass grafting was 31.2% (66/226), graft removal/in situ repair 34% (137/403), primary closure of the arterial defect 62.5% (10/16), and for miscellaneous open procedures 41.3% (33/80), p = .019. Among the subgroups of in situ repair, homografts were associated with a higher mortality than impregnated prosthetic grafts (p = .047). There was no difference in recurrent AEF-free rates between open and endovascular procedures. Extra-anatomical bypass/graft removal and in situ repair had a lower AEF recurrence rate than primary closure and homografts. Late sepsis occurred more often after endovascular surgery (2-year rates 42% vs. 19% for open, p = .001). The early survival benefit of endovascular surgery was blunted during follow-up, although it remained significant (p < .001). Within the in situ repair group, impregnated prosthetic grafts were associated with the worst overall and AEF related mortality free rates and vein grafts with the best. No recurrence, sepsis, or mortality was reported following staged endograft placement to open repair after a mean follow-up of 16.8 months (p = .18, p = .22, and p = .006, respectively, compared with patients in other groups).

CONCLUSIONS

Endovascular surgery, where appropriate, is associated with better early survival than open surgery for secondary AEFs. Most of this benefit is lost during long-term follow-up, implying that a staged approach with early conversion to in situ vein grafting may achieve the best results in selected patients.

Endovascular Graft Infection: Preliminary Results of an International Enquiry

Purpose:

To investigate the frequency of aortoiliac endovascular graft infections and seek the main factors influencing their development.

Methods:

To augment personal experience (1 case), a questionnaire was sent to 40 international centers of vascular and endovascular surgery. The literature was also reviewed to collect data on infections developing in endovascular grafts.

Results:

The survey (85% response rate) and literature review identified 62 cases of infected endovascular grafts (0.4% frequency of endograft infection). In 22 (35%) patients, the infection manifested initially with vague symptoms only, but 41 (65%) patients eventually presented with abdominal abscess, groin fistula, and septic embolization. Common bacteria, such as Staphylococcus aureus, were identified as the cause of most infections (54.5%). The majority (49, 79%) of the 62 patients were treated surgically; 11 (17.7%) patients received conservative therapy (no therapeutic data in 2 patients). Overall mortality was 27.4% (17/62), and operative mortality was 16.3% (8/49). Conservative treatment led to a mortality rate of 36.4% (4/11). The mean follow-up for all patients was 47.8 weeks. Possible factors influencing the development of an infection were secondary adjunctive procedures, immunosuppression, treatment of false aneurysms, and infected central lines.

Conclusions:

Infected endovascular grafts are an urgent problem that has been heretofore underestimated and will probably increase as follow-up lengthens. New techniques should be sought to expedite the diagnosis, and an international registry should be set up to provide validated data.

Aortoduodenal Fistula after Abdominal Aortic Stent Graft Presenting with Extremity Abscesses

Aortoenteric fistula (AEF) has been described after endovascular stent graft repair of abdominal aortic aneurysms (EVAR). AEF after EVAR has been associated with aneurysm growth, endoleak, migration, and aortic inflammation. We report a patient with an AEF presenting 2 years after EVAR with two abscesses in the right leg. A computed tomographic scan showed a gas-filled thrombus lining the right limb of his graft. At conversion, no endoleak, device migration, or residual aneurysm sac was found. AEF can occur after endoluminal stent graft (ELG) in the absence of aneurysm growth, endoleak, migration, or inflammation. AEF can cause ELG infection and extremity infection.

Portal vein pseudoaneurysm with portoenteric fistula: an unusual cause for massive gastrointestinal hemorrhage

Pancreaticoduodenectomy (Whipple's procedure) is a commonly performed procedure for the treatment of pancreatic malignancies. Postoperative bleeding from adjacent arteries is a well-established complication of this procedure. This article describes an unusual case of massive gastrointestinal bleeding following pancreaticoduodenectomy due to the development of a portal vein pseudoaneurysm with a portoenteric fistula. The diagnosis was confirmed with multidetector computed tomography angiography; the different endovascular treatment options are discussed.

Aortoduodenal fistula 5 years after endovascular abdominal aortic aneurysm repair with the Ancure stent graft

We report a case of aortoduodenal fistula 5 years after uncomplicated endovascular abdominal aortic aneurysm repair. The diagnosis was confirmed by abdominal computed tomography scan and esophagogastroduodenoscopy. The patient was successfully treated with primary duodenal repair, removal of the infected graft, in situ placement of a bifurcated graft, and omental interposition. Review of the literature identifies this as one of very few documented aortoduodenal fistulas after endovascular aneurysm repair. Fistulization occurred despite accurate stent graft placement without migration, endoleak, or aortic sac size enlargement on annual postoperative imaging studies.

Neoaortic Reconstruction for Aortic Graft Infection: Need for Endovascular Adjunctive Therapies?

Neoaortic reconstruction using an autogenous conduit is an increasingly accepted option for the management of aortic graft infections. However, this approach is not without technical challenges and potential graft-related problems, some of which can be solved with endovascular techniques. All patients who underwent neoaortic reconstruction with femoral-popliteal vein for aortic graft infection over a 6-year period were identified from the operative registry. Those patients requiring endovascular adjunctive therapies form the basis of this report. Of 17 cases of neoaortic reconstruction for aortic graft infection, five (29%) required endovascular adjunctive procedures. These included stent placement for graft stenosis (n = 3), stent graft placement for proximal anastomotic stenosis (n = 1), and stent graft placement for anastomotic disruption (n = 1). While two of these procedures occurred within 30 days of the original neoaortic reconstruction, three were required during late follow-up. Although there were no direct complications related to the endovascular procedures, the patient with anastomotic disruption died within 30 days of causes unrelated to the endovascular procedure. Primary patency of neoaortic reconstruction was 87% at 30 days and 61% at 3 years, with assisted primary patency increasing to 100% at 3 years after endovascular adjunctive intervention. While neoaortic reconstruction using an autogenous conduit for aortic graft infection has proven durability, it is not without potential early and late graft complications. When graft problems occur, endovascular options are an attractive alternative to reoperative open aortic procedures, especially in the setting of a vastly altered surgical field.

Nonoperative approach to endotension

OBJECTIVE

The necessity of operative treatment of endotension after endovascular grafting of abdominal aortic aneurysms (endovascular aneurysm repair; EVAR) is under debate. The proposed causes of endotension and related treatment protocols are controversial. We report the outcome of a nonoperative approach to five patients with endotension after EVAR.

METHODS

From February 1997 to August 2004, 160 patients who underwent EVAR of an infrarenal abdominal aortic aneurysm were evaluated for the incidence of endotension. According to the endovascular protocol, plain radiographs, spiral computed tomography, and angiography were performed before and after surgery for follow-up. To detect endotension, spiral computed tomography was performed by using a delayed imaging technique after the infusion of contrast medium. Endotension was defined as an aneurysm sac enlargement after EVAR without evidence of endoleak. Aneurysm sac rupture was defined as discontinuity of the calcific rim of the aneurysmal sac and the presence of intra-aneurysmal fluid outside the sac.

RESULTS

We found five (3.1%) patients with endotension. Three of these experienced aneurysmal sac rupture. Only one of the three was underwent operation on experiencing sudden intestinal occlusion due to intra-abdominal adhesions. This patient had no intra-abdominal or retroperitoneal bleeding or hematoma but died after intensive care as a result of non-aneurysm-related problems. Four patients with endotension are still being closely followed up according to our surveillance protocol, and they are doing clinically well. After rupture, clear shrinking of the aneurysm sac was seen in two patients.

CONCLUSIONS

Endotension after EVAR may cause subsequent aneurysm rupture. Endotension is evidently not associated with endoleak I to III provided that the endovascular graft is maintained in appropriate position and that free endovascular flow is observed. We propose to consider a nonoperative approach in the clinically asymptomatic patient with aneurysm enlargement after EVAR if endoleak is excluded by well-performed imaging techniques.

Aortoesophageal fistula secondary to stent-graft repair of the thoracic aorta

PURPOSE

To report the incidence and management of aortoesophageal fistula (AEF) secondary to endovascular stent-graft repair of the descending thoracic aorta.

METHODS

A retrospective review was conducted of patients treated at our facility between July 1999 and June 2003. During this interval, 60 patients (46 men; average age 66+/-10 years) underwent thoracic aortic stent-graft placement for a variety of pathologies.

RESULTS

AEF occurred in 3 (5%) patients. One 62-year-old man presented with recurrent back pain and fever and died suddenly due to fatal exsanguination; the AEF was revealed at necropsy. The other 2 patients (both women) presented with hematemesis after endovascular repair of thoracic aortic aneurysms. AEF was detected by esophagogastroduodenoscopy. Both patients were treated conservatively, as open surgical repair was refused because of their general condition. Both patients developed severe mediastinitis and died after 5 weeks and 10 months, respectively.

CONCLUSIONS

Aortoesophageal fistula is, in our experience, a catastrophic complication of endovascular stent-graft placement. Treatment options are very limited, as these patients are usually not candidates for open surgery. Outcome under conservative management is, however, almost invariably fatal.

Aortoenteric fistula due to endoleak coil embolization after endovascular AAA repair

PURPOSE

To report a late complication associated with embolization coils used to treat an endoleak after endovascular abdominal aortic aneurysm (AAA) repair.

CASE REPORT

A 79-year-old man with a 5.8-cm AAA underwent endovascular repair with an Ancure graft in 1997. A persistent type I endoleak was identified on serial postoperative computed tomographic scans. Three transarterial coil embolization procedures were performed to treat an endoleak from the proximal and right distal attachment sites with outflow by the inferior mesenteric and lumbar arteries. Coil embolization was ultimately successful in sealing the endoleak, and the AAA decreased in size. Four years later, the patient developed an aortoenteric fistula due to erosion of the metallic embolization coils into the duodenum. The endograft was explanted and an extra-anatomical bypass inserted.

CONCLUSIONS

Coil embolization to treat endoleaks can, on rare occasions, be the cause of aortoenteric fistula. Lifelong follow-up of stent-graft patients is required.