Aortoduodenal fistula after endovascular stent-graft of an abdominal aortic aneurysm

Aortoenteric Fistulas Following Endovascular Aortic Aneurysm Repair: A Review

BackgroundSecondary aortoenteric fistulas (SAEF) following endovascular aortic repair (EVAR) is an extremely rare event but life threatening. Our review offers comprehensive knowledge on pathophysiology, clinical presentation, diagnosis, and treatment options.AimTo summarize the current literature regarding pathophysiology, clinical, diagnostic and therapeutic approach of aortoenteric fistulas secondary to EVAR.MethodsWe performed a literature search in Pubmed/MEDLINE to identify the literature published about SAEF after EVAR. Cases were summarized in a table and prevalences. Other relevant literature was included in the results sections.ResultsA total of 35 reports (single cases and small series) with 45 patients were included. SAEF after EVAR can result from infection, inflammation, or mechanical factors. Clinical presentation is often non-specific, ranging from a gastrointestinal herald bleed to hemorrhagic shock, or malaise and general infection-related symptoms. Cross-sectional imaging plays a critical role in diagnosing SAEF. The treatment approach involves a multidisciplinary team approach and requires broad-spectrum intravenous antibiotics, endovascular intervention for urgent hemorrhage control, and open surgical intervention for definitive repair. Long-term antimicrobial therapy is essential to avoid reinfection.ConclusionsSAEF following EVAR represents a complex, life-threatening condition with limited evidence-based management strategies. Given the growing prevalence of endovascular procedures, comprehensive knowledge of SAEF is crucial for all health care providers to improve early diagnosis and outcomes.

Quantifying the burden of survivorship associated with infrarenal abdominal aortic aneurysms

OBJECTIVES

Survivorship encompasses the physical, psychological, social, functional, and economic experience of a living with a chronic condition for both the patient and their caregiver. It is made up of nine distinct domains and remains understudied in nononcological pathologies, including infrarenal abdominal aortic aneurysmal disease (AAA). This review aims to quantify the extent to which existing AAA literature addresses the burden of survivorship.

METHODS

The MEDLINE, EMBASE, and PsychINFO databases were searched from 1989 through September 2022. Randomized controlled trials, observational studies, and case series were included. Eligible studies had to detail outcomes related to survivorship in patients with AAA. Owing to the heterogeneity between studies and outcomes, no meta-analysis was conducted. Study quality was assessed with specific risk of bias tools.

RESULTS

A total of 158 studies were included. Of these, only five (treatment complications, physical functioning, comorbidities, caregivers, and mental health) of the nine domains of survivorship have been studied previously. The available evidence is of variable quality; most studies display a moderate to high risk of bias, are of an observational study design, are based within a limited number of countries, and consist of an insufficient follow-up period. The most frequent complication after EVAR was endoleak. EVAR is associated with poorer long-term outcomes compared with open surgical repair in most studies retrieved. EVAR showed better outcomes in regard to physical functioning in the short term, but this advantage was lost in the long term. The most common comorbidity studied was obesity. No significant differences were found between open surgical repair and EVAR in terms of impact on caregivers. Depression is associated with various comorbidities and increased the risk of a nonhospital discharge.

CONCLUSIONS

This review highlights the absence of robust evidence regarding survivorship in AAA. As a result, contemporary treatment guidelines rely on historic quality-of-life data that are narrow in scope and nonrepresentative of contemporary clinical practice. As such, there is an urgent need to reevaluate the aims and methodology associated with traditional quality-of-life research moving forward.

Secondary Aorto-Colonic Fistula: A Case Report and Literature Review of a Rare Complication after EVAR

Background: Aorto-enteric fistula (AEF) is a rare but fatal condition. The incidence of the overall AEF was approximately 0.36–2%, but the incidence of the aorto-colonic fistula was scarcely reported. A history of abdominal pain, fever, or gastrointestinal bleeding (GIB) in a patient with a history of aortic intervention should be highly suspected of this condition. This report describes a patient with lower GIB after an endovascular aneurysm repair (EVAR) for a symptomatic abdominal aortic aneurysm (AAA). Case Presentation: A 65-year-old man with a history of EVAR for symptomatic AAA presented with a massive lower GIB for two weeks. He also had a history of left lower quadrant pain and low-grade fever. Diverticular disease was suspected, and medical treatment was administered. After the initial conservative treatment, a colonoscopy was performed. The findings showed a fistula that exposed an aortic stent graft at the left-sided colon. An aorto-colonic fistula was diagnosed. After administering intravenous (IV) antibiotics, a staged axillo-bifemoral bypass graft with aortic stent graft explantation was performed. The patient recovered well and was discharged home after a month of hospitalization and IV antibiotics. Conclusion: In a patient with a history of aortic intervention, any abdominal pain, unknown fever, or even GIB should be suspected of complications of aortic intervention. Highly suspicious of this rare condition is the key to an early diagnosis and prompt treatment.

Treatment of Post-Evar Aortoduodenal Fistula Without Endograft Excision

An 80 year-old gentleman presented with aortoduodenal fistula 2 months after uncomplicated endovascular aneurysm repair (EVAR). Upon laparotomy and fistula takedown, there was no active hemorrhage from the excluded aneurysm. It was theorized the fistula had originated from an occult type II endoleak which had since thrombosed. The duodenum was repaired primarily; the anterior defect in the aneurysm sac was packed and covered with omentum. The patient recovered uneventfully and remains well after 9 months. This is the first case, to our knowledge, of a post-EVAR aortoduodenal fistula successfully treated without endograft excision.

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.

Aortoenteric Fistula: A Late Complication of Endovascular Repair of an Inflammatory Abdominal Aortic Aneurysm

Endovascular repair provides a reasonable alternative to open repair for the treatment of abdominal aortic aneurysms in select cases. Although the endovascular approach may be preferable for inflammatory aneurysms, aggressive surveillance is needed to monitor for long-term complications. A 61-year-old man underwent endovascular exclusion of a symptomatic inflammatory abdominal aortic aneurysm with an AneuRx bifurcated aortic prosthesis. He presented with gastrointestinal bleeding 51/2 months later and was found to have an aortoenteric fistula involving the third portion of the duodenum. The aneurysm had expanded significantly at the proximal neck. The patient underwent successful removal of the device, aortic ligation, and extraanatomic bypass. Aortoenteric fistula is a rare but now established complication of endovascular aneurysm repair. The pathophysiology in these cases remains unclear. The presence of inflammation and endoleak may predispose to further aneurysmal degeneration.

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.

Results from the Multicenter Study on Aortoenteric Fistulization After Stent Grafting of the Abdominal Aorta (MAEFISTO)

OBJECTIVE

This study investigated the frequency, clinical features, therapeutic options, and results of aortoenteric fistulas (AEFs) developing after endovascular abdominal aortic repair (EVAR).

METHODS

Eight Italian centers with an EVAR program participated in this retrospective multicenter study and collected data on AEFs that developed after a previous EVAR.

RESULTS

A total of 3932 patients underwent EVAR between 1997 and 2013 at the participating centers. During the same period, 32 patients presented with an AEF during EVAR follow-up, 21 with original EVAR performed for atherosclerotic aneurysmal disease (ATS group) and 11 with the original EVAR performed for a postsurgical pseudoaneurysm (PSA group). The incidence of AEF development after EVAR was 0.46% in the ATS group and 3.9% in the PSA group. Anastomotic PSA as the indication to EVAR (P < .0001) and urgent/emergency EVAR (P = .01) were significantly associated with AEF development. Median time between EVAR and the AEF diagnosis was 32 months (interquartile range, 11-75 months) for the ATS group and 14 months (interquartile range, 10.5-21.5 months) for the PSA group. Among five AEF patients treated conservatively, two (40%) died, at 7 and 15 months, and the remaining three were alive at a median follow-up of 12 months. The AEF was treated surgically in 27 patients, including aortic stent graft explantation in all cases, in situ aortic reconstruction in 14 (52%), and extra-anatomic bypass in 13 (48%). Perioperative mortality was 37% (10 of 27). No additional aortic-related death was recorded in operated-on patients at a median follow-up of 28 months.

CONCLUSIONS

Late AEFs rarely occur during EVAR follow-up, but the risk is significantly increased when EVAR is performed for PSA after previous aortic surgery and EVAR is performed as an emergency. Conservative and surgical treatment of post-EVAR AEF are both associated with high mortality. However, beyond the perioperative period, surgical correction of AEFs appears to be durable at midterm follow-up.

Aortoenteric fistula as a complication of open reconstruction and endovascular repair of abdominal aorta

The paper intends to present a review of imaging characteristics of secondary aortoenteric fistula (AEF). Mechanical injury, infection, and adherence of a bowel segment to the aorta or aortic graft are major etiologic factors of AEF after open aortic repair. The pathogenesis of AEF formation after endovascular abdominal aortic repair is related to mechanical failure of the stent-graft, to stent graft infection, and to persistent pressurization of the aneurysmal sac. The major clinical manifestations of AEF comprise haematemesis, melaena, abdominal pain, sepsis, and fever. CT is the initial diagnostic modality of choice in a stable patient. However, the majority of reported CT appearances are not specific. In case of equivocal CT scans and clinical suspicion of AEF, scintigraphy, (67)Ga citrate scans or (18)F-FDG PET/CT is useful. Diagnostic accuracy of endoscopy in evaluation of AEF is low; nevertheless it allows to evaluate other than AEF etiologies of gastrointestinal bleeding. Without adequate therapy, AEF is lethal. Conventional surgical treatment is associated with high morbidity and mortality. The endovascular repair may be an option in hemodynamically unstable and high-risk surgical patients. We also illustrate an example of a secondary AEF with highly specific albeit rare radiologic picture from our institution.

Secondary aortoduodenal fistula following endovascular repair of inflammatory abdominal aortic aneurysm due to Streptococcus anginosus infection: A case report and literature review

INTRODUCTION

Aortoenteric fistula is a rare but very serious complication of both surgical and endovascular abdominal aortic reconstruction. Since the advent of endovascular abdominal aortic aneurysm repair (EVAR), 20 cases of aortoduodenal fistula associated with aortic stent grafts have been reported.¹ However, only a handful has been reported following inflammatory abdominal aortic aneurysm repair. It most commonly presents with bleeding, usually from the upper gastro-intestinal tract. With recent advances in the screening, diagnosis and management of abdominal aortic aneurysms either surgically or through an endovascular approach, the diagnosis of an aortoduodenal fistula in patients with gastro-intestinal bleeding must be suspected and excluded.

PRESENTATION OF CASE

We describe a case of secondary aortoduodenal fistula that occurred two and a half years following endovascular stent graft repair of an inflammatory abdominal aortic aneurysm. We also outline the emergency correction plan and the attempts at repair.

DISCUSSION

This case defies the general concept that patients with inflammatory abdominal aortic aneurysms are relatively immune to rupture. Although the presence of a peri-aneurysm thick inflammatory membrane decreases the possibility of rupture, these patients are more susceptible to other related complications such as aorto-enteric and aorto-caval fistulas.² This case also demonstrates the peculiar presence of Streptococcus anginosus as the pathological organism leading to graft infection and subsequent fistula, as opposed to enterococci which are often found in endograft infection.

CONCLUSION

Aorto-enteric fistulas are associated with a grave prognosis. Early diagnosis is crucial and extra vigilance should be taken in cases of inflammatory AAA.

Aortoenteric fistula diagnosed by double balloon enteroscopy: a case report

A secondary aortoenteric fistula (AEF) is a direct communication between the gastrointestinal tract and the aorta in a patient who has undergone major surgery on the aorta, often an aorta graft operation. We experienced a patient who had undergone graft interposition for abdominal aortic aneurysm and was admitted due to three episodes of hematemesis and following hamatochezia. Gastroscopy, colonoscopy, and radioactive iodine scan failed to identify the bleeding site in the patient. He was diagnosed with AEF by double balloon enteroscopy and recovered after surgical intervention.

Aortoenteric fistulae: present-day management

An aortoenteric fistula (AEF) is a communication between the aorta and an adjacent loop of the bowel. The three most useful diagnostic modalities for detecting AEF are abdominal computed tomography scan with intravenous contrast, esophagogastroduodenoscopy, and arteriography. The treatment of AEFs has improved in recent years, but despite the multiple surgical techniques reported, many of the patients do not survive or are left debilitated after treatment. Endovascular repair is an efficient and safe method to stabilize patients with life-threatening AEFs. The aim of this study is to provide a comprehensive and synthetic review of the latest advantages on the diagnosis and management of primary and secondary AEF.

Conversion to open repair after endografting for abdominal aortic aneurysm: a review of causes, incidence, results, and surgical techniques of reconstruction

PURPOSE

To review the incidence, causes, and mortality rates of early and late conversion to open surgery after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm (AAA).

METHODS

A systematic search of the English-language literature from 2002 to 2009 was performed by interrogation of the PubMed, MEDLINE, and EMBASE databases. Studies were included if they: (1) had >100 patients treated with EVAR and (2) provided adequate data to calculate incidence and associated mortality rates. The search yielded 13 articles with sufficient data to analyze early conversion (12,236 patients, 178 conversions) and 15 articles with available data for late conversion (14,298 patients, 279 conversions).

RESULTS

The rate of early conversion among the 13 articles reviewed ranged from 0.8% to 5.9%; more recent studies carried lower rates of early conversion. Mortality rates of early conversion varied between 0% and 28.5%. Overall, there were 178 (1.5%) early conversions among the 12,236 AAAs treated with EVAR, with an average mortality of 12.4%. The rates of late conversion ranged from 0.4% to 22%. Of the 14,289 AAA patients undergoing endovascular repair, 279 (1.9%) required late conversion; the mortality rate was 10%.

CONCLUSION

Though the incidence is gradually declining, secondary interventions persist as the Achilles' heel of EVAR. A lifelong follow-up strategy for AAA patients treated with EVAR is essential for early detection and treatment of complications of the procedure. Vascular surgeons should be familiar with the complex open conversion procedures.

Infecção em endoprótese

A infecção envolvendo endopróteses é uma complicação pouco frequente, associada a elevadas taxas de mortalidade. A apresentação clínica é geralmente tardia, podendo variar de sintomas inespecíficos até complicações graves como pseudoaneurisma e fístula aortoentérica. O diagnóstico envolve alto índice de suspeição e investigação com exames de imagem e laboratoriais. O tratamento segue os preceitos da infecção de prótese em cirurgia convencional, indicando-se, para a maioria dos pacientes, a excisão cirúrgica acompanhada da revascularização in situ ou extra-anatômica. O tratamento conservador fica reservado para casos selecionados.

Aortoenteric fistulas: CT features and potential mimics

Prompt diagnosis of aortoenteric fistulas is imperative for patient survival. The clinical signs of aortoenteric fistula include hematemesis, melena, sepsis, and abdominal pain, but the condition also may be clinically occult. Because clinical signs may not be present or may not be sufficiently specific, imaging is most often necessary to achieve an accurate diagnosis. Although no single imaging modality demonstrates the condition with sufficient sensitivity and specificity, computed tomography (CT), owing to its widespread availability and high efficiency, has become the imaging modality of choice for evaluations in the emergency setting. CT has widely variable sensitivity (40%-90%) and specificity (33%-100%) for the diagnosis of aortoenteric fistulas. To use this modality effectively for the initial diagnostic examination, radiologists must be familiar with the spectrum of CT appearances. Mimics of aortoenteric fistulas include retroperitoneal fibrosis, infected aortic aneurysm, infectious aortitis, and perigraft infection without fistulization. Differentiation is aided by the observation of ectopic gas, loss of the normal fat plane, extravasation of aortic contrast material into the enteric lumen, or leakage of enteric contrast material into the paraprosthetic space; these features are highly suggestive of aortoenteric fistula in a patient with bleeding in the gastrointestinal tract.

Is F 18 Fluorodeoxyglucose Positron Emission Tomography Too Sensitive for the Diagnosis of Vascular Endograft Infection?

We report a case of a false positive fluorodeoxyglucose positron emission tomography (FDG-PET) scan in a patient who presented with abdominal pain, and gastrointestinal bleeding accompanied by elevation of inflammatory markers, seven weeks after a proximal type I endoleak repair with a cuff extension. Aortoenteric fistula and endograft infection was ruled out by laparotomy. FDG-PET image may have a role in diagnosis of infection, but false positive results are possible and caution is necessary if other data are non-confirmatory.

Unusual forms of ruptured abdominal aortic aneurysms

Over 95% of abdominal aortic aneurysms (AAAs) rupture into the retroperitoneal space. Rare types of AAA ruptures comprise ruptures into the inferior vena cava with aortocaval fistula formation (ACF), ruptures into the duodenum with formation of a primary aortoduodenal fistula (ADF), and chronic contained ruptures (CCRs). This article presents a study of 41 cases with unusual forms of ruptured AAA of a series of 506 patients with AAA rupture treated within a 14-year period. There were 11 cases of CCR, 5 cases with ADF, and 25 cases with ACF. The correct preoperative diagnosis was established in 6 (of 11) cases of CCR, in 2 (of 5) cases of primary ADF, and in 13 (of 25) cases of ACF. AAA replacement was performed in 8 cases using a tube graft, whereas a bifurcated graft was used in 31 patients because of the distant extent of the atherosclerotic/aneurysmatic lesions engaging iliac arteries. Two patients had an axillobifemoral bypass. The overall 30-day mortality rate was 19% (8 of 41), with subgroup mortality rates of 0 (CCR), 60% (ADF), and 20% (ACF). Diagnosis and treatment are simplest in cases of CCR and the most complicated in cases of ADF.

[Repair of secondary aortoenteric fistulas. A systematic review]

We performed a systematic review of the literature on the diagnosis and treatment of secondary aortoenteric fistulas (AEF). A MEDLINE search was performed of articles published in English or Spanish between January 1991 and August 2006. Diagnostic methods, treatment modalities and the results of surgical treatment were analyzed. The most frequent first aortic surgery associated with AEF was repair of abdominal aortic aneurysm (54.31%). The most common form of presentation was gastrointestinal bleeding. Repair through in situ prosthetic replacement had the lowest early mortality rates (8-13.3%) compared with graft excision and extraanatomic revascularization (18.2-44%). AEF is a serious entity and diagnosis requires a high index of suspicion based on clinical findings and indirect data from imaging techniques (computed tomography). The most appropriate therapeutic option continues to be controversial.

Prosthetic stent graft infection after endovascular abdominal aortic aneurysm repair

OBJECTIVE

The purpose of this report is to discuss the incidence, diagnosis, and management of stent graft infections after endovascular aneurysm repair (EVAR).

METHODS

Data were collected from the hospital database and medical case notes for all patients with infected endografts after elective or emergency EVAR for abdominal aortic aneurysm (AAA) during the last 8 years in two university teaching hospitals in Northern Ireland. The data included the patient's age, gender, presentation of sepsis, treatment offered, and the ultimate outcome. The diagnosis of graft-related sepsis was established by a combination of investigations including inflammatory markers, labelled white cell scan, computed tomography (CT) scan, microbiology cultures, and postmortem examination.

RESULTS

Graft-related septic complications occurred in six of 509 patients, including 433 elective repairs and 76 emergency endografts for ruptured AAA. Two patients presented with left psoas abscess and were treated successfully with extra-anatomic bypass and removal of the infected stent graft. Two more patients presented with infected graft without other evidence of intra-abdominal sepsis: one underwent successful removal of the infected prosthesis with extra-anatomical bypass, and the other was treated conservatively and died of progressively worsening sepsis. The fifth patient presented with unexplained fever and died suddenly, with a postmortem diagnosis of aortoenteric fistula and ruptured aneurysm. The last patient presented with an aortoenteric fistula, was treated conservatively in view of concurrent myelodysplasia, and died of possible aneurysm rupture.

CONCLUSION

This report emphasizes the need for continued awareness of potential graft-related septic complications in patients undergoing EVAR of AAA. Attention to detail with regard to sterility and antibiotic prophylaxis during stent grafting and during any secondary interventions is vital in reducing the risk of infection. In addition, early recognition and prompt treatment are essential for a successful outcome.

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.

Aortoenteric fistula as a late complication of thrombolysis and bare metal stenting for perioperative occlusion of aortofemoral bypass

We previously described the case of a 47-year-old man who experienced perioperative graft occlusion after infrarenal aortic endarterectomy and aortobifemoral expanded polytetrafluoroethylene bypass graft for occlusive disease. The patient was treated with local graft thrombolysis and stenting of an intimal flap at the level of the endarterectomized aorta next to the aortic anastomosis. An urgent laparotomy performed 6 years later showed aortic wall perforation by the stent with a large aortoenteric fistula. Surgical treatment included removal of the stent and the aortobifemoral graft, bowel repair, and extra-anatomic lower-limb revascularization by axillofemoral and cross-femoral bypass grafting. The patient was discharged 12 days later with no early complications. Although local thrombolysis and stenting may be a technically feasible technique instead of reoperation in early aortofemoral graft thrombosis, long-term results of this procedure may be affected by perigraft hematoma due to perioperative thrombolysis, increased risk of infection due to the prolonged intragraft cannulation, and risk of stent-related aortic injury, especially if an endarterectomy has been performed. All these issues may increase the risk of late aortoenteric fistula. More experience with hybrid, open/endovascular procedures, and more contemporary stent-based devices is needed to assess the efficacy and safety of this alternative treatment.

Aortoenteric Fistula After Endovascular Stent Grafting for an Abdominal Aortic Aneurysm: Report of a Case

We report a case of an aortoenteric fistula (AEF) developing after endovascular stent grafting (EVSG) for an abdominal aortic aneurysm (AAA). A 69-year-old male patient with a history of panperitonitis caused by rectal perforation underwent EVSG for an AAA. A follow-up contrast-enhanced computed tomography (CT) scan, done 12 months after the EVSG, confirmed shrinkage of the AAA with no endoleak. However, 19 months postoperatively, an AEF developed between the AAA and the jejunum. Although there was no endoleak on a subsequent CT scan, we noted enlargement of the AAA and inflammatory changes in the surrounding tissue. The patient was treated surgically and discharged in good health 74 days postoperatively. Thus, one should consider the possibility of this devastating complication, even in patients without an endoleak, after EVSG for AAA.

Late Infection of an Endovascular Stent Graft with Septic Embolization, Colonic Perforation, and Aortoduodenal Fistula

We report on a 52-year-old male who developed late stent graft infection resulting in infective aneurysm formation with systemic septic embolization and aortoduodenal fistulation 9 months following endoluminal repair of an abdominal aortic aneurysm. Although endoluminal stent graft infection and erosion into surrounding viscera is rare, we highlight the need for awareness of this potentially catastrophic complication.

Recurrent Aortoenteric Fistula: Case Report and Review

Aortoenteric fistulas (AEFs) are abnormal communications between the aorta and the bowel most frequently resulting from prosthetic graft erosion. Despite advances in surgery and medical technology, these entities are still associated with significant morbidity and mortality for the patient. Multiple case reports and reviews have attempted to elucidate the nature of AEFs in an effort to better characterize and manage these entities. However, reports of recurrence of this process are extremely rare. In this article, we describe a unique case of recurrence of an AEF that was successfully managed with primary aortic oversew and bowel resection. We will also review the literature on AEFs with a comprehensive overview on background, presentation, diagnosis, and current management options.

Computed Tomography and Ultrasound in Follow-up of Patients after Endovascular Repair of Abdominal Aortic Aneurysm

The purpose of this study was to compare our experience with duplex ultrasonography (US) and computed tomography (CT) for the routine follow-up of patients after endovascular repair (EVAR) of abdominal aortic aneurysm (AAA). We reviewed the electronic charts and radiologic exams of the first 125 patients (113 males, 12 females, median age of 76 years, range 48-98 years) with AAA treated by EVAR from June 1996 to November 2001. Our follow-up protocol included serial CT and US at regular intervals after the procedure (before discharge, at 1 month, and then every 6 months). Adequacy of each exam, ability to detect endoleaks, measurements of AAA diameter, and ability to determine graft patency were compared. For endoleak detection, comparison between CT and US was done using CT as the gold standard. A total of 608 exams, 337 CTs and 271 US, were performed 1 day to 5 years after endovascular aneurysm repair; 98% of CT and 74% of US were technically adequate. Contrary to CT, the proportion of adequate US exam was significantly less in patients with higher body mass index (BMI > or = 30 = 54% vs. BMI < 30 = 81%, p < 0.001) and for pre-discharge US compared to the post-discharge US (54% vs. 88%, p = 0.0005). Concurrent scan pairs were obtained in 252 instances in 107 patients (1-8 pairs per patient). Excellent correlation between AAA diameter measured on CT and US was noted (correlation coefficient of 0.9, p < 0.0001). However, agreement was poor. CT anteroposterior (AP) and transverse measurements were on average 2.9 mm (95% limits of agreement = -7 to 13 mm) and 1.8 mm (95% limits of agreement = -9 to 12 mm) greater than US. For AAA diameter change, there was no case of increase AP diameter on CT. However, in 23% (29/128 pairs of sets) of US, an increase in AAA size that could have influenced patient management (> or = 4 mm) was reported despite no change demonstrated on CT. For endoleak detection, sensitivity and specificity of US compared to that of CT was 25% and 89%. Similar sensitivity and specificity were noted when we excluded the first set (25% and 95%), sets done prior to 2000 (30% and 89%), inadequate CT or US scans (31% and 98%), or duplicate sets of results for each patient (28% and 81%). Of the 27 endoleaks missed on US in 17 patients, 2 were type I endoleaks. None of the four endoleaks seen only on US were type I endoleak. US usefulness prior to discharge was reduced by the high rate of inadequate exam, especially in obese patients. Despite the excellent correlation in AAA diameter between US and CT, there was significant disagreement in AAA diameter measurement and diameter change. Sensitivity of nonstandardized US for endoleak was low compared to CT. CT remains our primary imaging study after EVAR, but standardization of post-EVAR US technique may improve its accuracy.

Aortoenteric fistula development following endovascular abdominal aortic aneurysm repair: a case report

Aortoenteric fistulae (AEF) are now known to occur following endovascular repair of abdominal aortic aneurysms (AAA), presumably because of mechanical forces of dislodged or migrating devices. We present an unusual case of fistula development between the ileum and an AAA presenting as a graft infection following endovascular AAA repair in the absence of direct mechanical strain. Continued pressurization of the aneurysm sac due to endoleak may predispose to this event, especially in large aneurysms. Aggressive surveillance and early interventions are necessary following all endovascular AAA repairs.

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.

Aortic stent-graft infection due to a presumed aortoenteric fistula

PURPOSE

To report a case of late stent-graft infection with aortoenteric fistula.

CASE REPORT

A 76-year-old Colombian man received an AneuRx stent-graft for a 5.5-cm infrarenal AAA. The aneurysm sac progressively shrank until 22 months postoperatively, when an increase in diameter was noted on magnetic resonance imaging without evidence of endoleak or air in the sac. Two months prior, the patient had developed fever and an elevated white blood cell count; he underwent a 6-week course of intravenous antibiotics. Shortly thereafter, the fever recurred, along with progressive weight loss, which prompted admission. The computed tomographic scan showed no evidence of endoleak, but gas collection was seen anteriorly in the sac; aspirated material was positive for a variety of organisms. At surgery 23 months after stent-graft implantation, pronounced inflammatory reaction and scarring were seen around the graft in conjunction with evidence of a healed duodenal perforation, suggestive of an aortoenteric fistula. The excised stent-graft was intact; no deterioration was seen. The patient had a protracted recovery but has been afebrile and asymptomatic >1 year after stent-graft explantation

CONCLUSIONS

Close surveillance after endovascular AAA repair is essential to detect late leaks, secondary migration, endotension, structural failure, and infection with or without aortoenteric fistula.