Aortoenteric fistula caused by a ruptured stent-graft: a case report

Three-step surgical treatment of aortoesophageal fistula after thoracic endovascular aortic repair: A case report

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The number of aortoesophageal fistula (AEF) after thoracic endovascular aortic repair (TEVAR) is recently increasing due to the spread of TEVAR.

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AEF is a rare but fatal disease, and only surgery can save the life of patients with AEF after TEVAR.

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The therapeutic strategy for AEF after TEVAR remains controversial.

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The three-step surgical approach described herein could be a useful therapeutic option for AEF after TEVAR.

Introduction

Aortoesophageal fistula (AEF) is a fatal complication results in sudden massive hematemesis. Although thoracic endovascular aortic repair (TEVAR) is an established method of treating aortic aneurysms or aortic dissection, the number of AEF after TEVAR is recently increasing due to the spread of TEVAR. However, the therapeutic strategy for AEF remains controversial.

Presentation of case

We describe a 71-year-old man with Stanford B aortic dissection and aortic aneurysm rupture treated by TEVAR who developed AEF between the thoracic aorta and upper thoracic esophagus 20 months thereafter. We applied a three-step surgical procedure for this patient comprising resection of the esophagus as the infectious source, removal of an aortic aneurysm with stent-graft and replacement of the aorta, and final reconstruction of the esophagus. Thereafter, the patient resumed oral intake and has remained relapse-free for 24 months without adverse events.

Discussion

Previous reports have described simultaneous resection of the esophagus and aortic stent-graft via a left thoracotomy followed by a two-step surgical reconstruction of the esophagus. We applied a three-step procedure consisting of resections of the esophagus and aortic stent-graft on separate occasions followed by esophageal reconstruction in this patient. The first procedure in the three-step approach is less stressful than that of the two-step approach.

Conclusion

The three-step surgical approach to treating AEF after TEVAR resulted in a good outcome for this patient. Thus, this surgical strategy is a useful option for treating AEF after TEVAR.

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.

Type IIIb endoleak after elective endovascular aneurysm repair: a systematic review

INTRODUCTION

The aim of this article is to investigate the presentation, etiology, management and outcomes of type IIIb endoleak after endovascular aneurysm repair (EVAR).

EVIDENCE ACQUISITION

Electronic bibliographic databases were searched to identify published reports of type IIIb endoleak after EVAR, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards.

EVIDENCE SYNTHESIS

In total 33 articles were identified reporting on a total of 50 patients spanning 19 years of EVAR (1998-2017). Some 11 device-types were used. The median time from implantation to intervention was 27 months (0-168). There was a significant aneurysm sac expansion in 69% of reported cases. Thirteen patients (26%) presented with aneurysm rupture. A definitive diagnosis of type IIIb endoleak made on computed tomographic angiography (CTA) in only 20% of cases. Proposed failure modes included suture breakage, graft erosion by stents, iatrogenic, graft infection and presumed manufacturing faults. Endoleak location was in the main body in 81% of reported cases. Almost one third (31%) of patients were treated with open repair. The remaining patients were treated with endovascular techniques or hybrid procedures. Some novel off-label endovascular solutions were proposed to maintain a bifurcated configuration. Thirty-day mortality in patients treated for aneurysm rupture was 50%. The 30-day mortality rate in non- rupture cases was 2% (endovascular 0% treatment, open 2%).

CONCLUSIONS

Type IIIb endoleak is a serious condition associated with a significant risk of rupture. Definitive diagnosis is challenging and has been described in almost all conventional devices. Most patients can be treated successfully by endovascular means, though maintaining a bifurcated configuration may require non-standard techniques or off-label use.

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.

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.

Successful endovascular management of an aortic rupture following stent placement for severe atherosclerotic stenosis: A case report

Aortic rupture during endovascular procedures is a devastating complication that mandates expedient intervention. The present report describes a case in which endovascular treatment was used to successfully manage an aortic rupture following placement of a covered stent graft for severe infrarenal aortic stenosis. Successful management of this case was the result of the procedure being performed in an operating room under appropriate anesthesia and close hemodynamic monitoring. Bilateral common femoral arterial access and use of covered aortic stent grafts also contributed to a favourable outcome.

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.

Fatores envolvidos na migração das endopróteses em pacientes submetidos ao tratamento endovascular do aneurisma da aorta abdominal

A migração da endoprótese é complicação do tratamento endovascular definida como deslocamento da ancoragem inicial. Para avaliação da migração, verifica-se a posição da endoprótese em relação a determinada região anatômica. Considerando o aneurisma da aorta abdominal infrarrenal, a área proximal de referência consiste na origem da artéria renal mais baixa e, na região distal, situa-se nas artérias ilíacas internas. Os pacientes deverão ser monitorizados por longos períodos, a fim de serem identificadas migrações, visto que estas ocorrem normalmente após 2 anos de implante. Para evitar migrações, forças mecânicas que propiciam fixação, determinadas por características dos dispositivos e incorporação da endoprótese, devem predominar sobre forças gravitacionais e hemodinâmicas que tendem a arrastar a prótese no sentido caudal. Angulação, extensão e diâmetro do colo, além da medida transversa do saco aneurismático, são importantes aspectos morfológicos do aneurisma relacionados à migração. Com relação à técnica, não se recomenda implante de endopróteses com sobredimensionamento excessivo (> 30%), por provocar dilatação do colo do aneurisma, além de dobras e vazamentos proximais que também contribuem para a migração. Por outro lado, endopróteses com mecanismos adicionais de fixação (ganchos, farpas e fixação suprarrenal) parecem apresentar menos migrações. O processo de incorporação das endopróteses ocorre parcialmente e parece não ser suficiente para impedir migrações tardias. Nesse sentido, estudos experimentais com endopróteses de maior porosidade e uso de substâncias que permitam maior fibroplasia e aderência da prótese à artéria vêm sendo realizados e parecem ser promissores. Esses aspectos serão discutidos nesta revisão.

AAA stent-grafts: past problems and future prospects

Endovascular aneurysm repair (EVAR) has quickly gained popularity for infrarenal abdominal aortic aneurysm repair during the last two decades. The improvement of available EVAR devices is critical for the advancement of patient care in vascular surgery. Problems are still associated with the grafts, many of which can necessitate the conversion of the patient to open repair, or even result in rupture of the aneurysm. This review attempts to address these problems, by highlighting why they occur and what the failings of the currently available stent grafts are, respectively. In addition, the review gives critical appraisal as to the novel methods required for dealing with these problems and identifies the new generation of stent grafts that are being or need to be designed and constructed in order to overcome the issues that are associated with the existing first- and second-generation devices.

[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.

Fungal Infection of Aortoiliac Endograft: A Case Report and Review of the Literature

Infection of aortoiliac endografts is, to date, a rare complication of endovascular surgery. Staphylococcus species are the most common responsible pathogens, just as in cases with infected grafts after open aortic surgery. We report a case of a 65-year-old man with a history of diabetes mellitus and bladder cancer who developed stent-graft infection 3 years after endovascular treatment for a 5.6 cm abdominal aortic aneurysm. The diagnosis of endograft infection was established radiologically by computed tomographic scans. After intravenous administration of antibiotics and fluids to improve his clinical condition, the patient underwent surgical excision of the infected prosthesis and a bifurcated rifampicin-impregnated Dacron graft was placed in situ. Cultures from the purulent fluid around the aorta and from the endograft revealed development of Candida albicans. To our knowledge, this is the first case of an infected endograft due to a fungus. The patient died from septic shock 3 days postoperatively in the intensive care unit.

Evolving strategies for the treatment of aortoenteric fistulas

BACKGROUND

Aortoenteric fistulas (AEFs) are a rare but often fatal cause of gastrointestinal bleeding. Operative repair of AEF has been historically associated with extremely high morbidity and mortality. We reviewed our experience of open surgical and endovascular treatment of AEF to compare outcomes over a contemporaneous time period.

METHODS

Over a 9-year period between January 1997 and January 2006, 16 patients (11 men and 5 women) were diagnosed with and treated for AEFs. Seven patients underwent open surgical repair, and nine, with anatomically suitable lesions, underwent endovascular repair. The outcome after treatment of these patients was investigated for survival, perioperative complications, length of hospital stay, and long-term disposition.

RESULTS

Three primary and 13 secondary AEFs were treated. The mean time from the initial aortic operation until AEF diagnosis was 5.9 years (range, 0.7-12.2 years) for patients with secondary AEFs. The overall 30-day mortality rate was 18.8%. One intraoperative death and one in-hospital death secondary to multisystem organ failure occurred in patients undergoing open repair. One in-hospital death related to persistent sepsis occurred in the endovascular group. The overall perioperative complication rate was 50.0%. Complications in the open group included sepsis, renal failure, bowel obstruction, and pancreatitis. Complications in the endovascular group were related to persistent sepsis. The mean in-hospital length of stay was significantly longer for patients undergoing open repair compared with endovascular repair (44.0 vs 19.4 days; P = .04). Four (80%) of five patients who were discharged from the hospital in the open group were placed in skilled nursing facilities, and seven (87.5%) of eight patients discharged in the endovascular group returned home. The median overall survival after hospital discharge was 23.1 months. There were no late aneurysm-related deaths or late deaths related to septic complications.

CONCLUSIONS

Patients with AEFs have limited overall survival. Endovascular therapy offers an alternative to open surgical repair, seems to be associated with decreased perioperative morbidity and mortality and a shorter in-hospital stay, and allows for acceptable survival given the presence of coexisting medical comorbidities. Furthermore, endovascular repair provides a therapeutic option to control bleeding and allow for continued intervention in a stabilized setting.

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.

Endovascular treatment of abdominal aortic aneurysms

BACKGROUND

Endovascular treatment of abdominal aortic aneurysms is a rapidly evolving technique that has gained broad acceptance in the treatment of patients with abdominal aortic aneurysms.

METHODS

A review of the English literature was done to determine the short- and long-term outcomes of endovascular repair of abdominal aortic aneurysms. Reports of complications such as endoleak, graft migration, graft limb occlusion, aneurysm rupture, and aneurysm enlargement were evaluated.

RESULTS

Short-term results of endovascular repair of abdominal aortic aneurysms are excellent. The necessity for open conversions is less than 5%. The cumulative risk of aneurysm rupture is approximately 1% per year. The coverall incidence of graft limb occlusion was 2.8% in the follow-up period. The cumulative risk for a secondary procedure was 12% at 1 year, 24% at 2 years, and 35% at 3 years. Moderate and severe neck angulation was associated with an increased incidence of adverse events in the follow-up period. Endografts have the potential to become infected and develop aortoduodenal fistula. The treatment of ruptured aneurysms with endovascular grafts has been successful and a technique that is increasingly used.

CONCLUSION

Endovascular treatment of abdominal aortic aneurysm is an effective technique with excellent short-term results. The long-term results remain to be determined. Ongoing surveillance is necessary to avoid late complications of aneurysm rupture.

Aortoiliac stent graft infection: current problems and management

Aortic stent graft infection is uncommon. Most cases have been described anecdotaly in single-case reports. After observing one case in our experience, we decided to review the literature and contact centers performing endovascular aortic repair to determine the frequency, risk factors, and current treatment of stent graft infection. The literature was reviewed and the authors of identified articles were contacted for further information. In addition, 40 centers specializing in endovascular treatment were contacted by means a dedicated questionnaire. A total of 65 aortic stent graft infections were identified, including 43 reported cases and 22 previously unpublished cases that were observed at specialized centers. Stent grafts were implanted in the aorta in 50 cases and in the iliac artery in 15 cases. The frequency of infection was 0.43%. The gender ratio was 4:1 (M:F). Twenty-three percent of patients had immunodeficiency factors. Placement was performed in an interventional radiology suite in 62.5% of cases and in a sterile operating theater in 37.5%. Also, 35.5% of patients underwent other vascular procedures during the course of study and 29.2% stent grafts benefited from adjuvant endovascular procedures. Infection was classified as low grade in 35.4% of patients and high grade in 64.6%. Thirty-one percent of infections were associated with aortoenteric fistula. The offending microorganism was Staphylococcus aureus in 54.5% of cases. Treatment was conservative in 18% of cases and surgical in 82%. Surgical treatment consisted of stent graft removal followed by either extraanatomical bypass (59.5%) or in situ prosthetic reconstruction (40.5%). Mortality was 18% overall, 36.4% after conservative treatment and 14% after surgical treatment ( p = 0.083). Mortality was 16% after surgical treatment with extraanatomical bypass vs. 5.8% surgical treatment with in situ reconstruction. From these results we conclude that stent graft infection is an uncommon occurrence associated with poorly defined risk factors. Surgical treatment with complete excision of the infected stent graft followed by in situ reconstruction provides the best outcome. Establishment of a multicenter register to record such complications is needed to confirm the findings of this study.

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.

The endovascular repair of abdominal aortic aneurysm: an update analysis of structural failure modes of endovascular stent grafts

Over the last decade, more than 25,000 endovascular stent grafts have been used to treat aortic aneurysms. Although results have been promising thus far, problems with endoleaks, material failure, device migration, and aneurysm rupture continue to be reported. Improvements in device material and design have contributed to the rapid growth and utility of these devices; however, material failure still remains a concerning mode for potential procedure failure. A review of the authors'experience with material failure and a review of the literature was conducted to help understand and comprehend the magnitude of this problem and try to determine its clinical significance.

Secondary aortoesophageal fistula after endoluminal exclusion because of thoracic aortic transection

Secondary aortoesophageal fistula (AEF) is a rare but catastrophic complication that occurs after thoracic aortic reconstruction. Recently endoluminal stent grafts have been used in selected patients with a thoracic aortic aneurysm, dissection, or traumatic aortic transection. A 24-year-old woman had massive upper gastrointestinal tract bleeding 15 months after endoluminal stent graft placement because of traumatic descending thoracic aortic transection. Evaluation demonstrated an AEF from the mid-esophagus to the endoluminal stent graft. The endoluminal graft was explanted, with primary repair of the thoracic aortic defect and simultaneous primary repair of the esophageal injury. The patient is well 15 months after open repair of the AEF.

Mechanical failure of prosthetic human implants: a 10-year experience with aortic stent graft devices

OBJECTIVE

The first endovascular stent graft was implanted to treat an abdominal aortic aneurysm more than a decade ago. This technique has evolved dramatically with the growing understanding of metallurgic and fabric sciences and improved device designs. However the potential for stent graft material failure remains. This investigation describes the incidence of material failure, potential modes of device fatigue, and the clinical significance of these failures.

METHODS

Six hundred eighty-six endovascular stent grafts were used to treat patients with aortic aneurysms. Device fatigue in the form of stent, suture fracture, or graft wear was identified with an analysis of follow-up radiographs and explanted stent grafts. A review of patient clinical histories, spiral computed tomographic scan studies, scanning electron microscopy, and energy dispersion spectroscopy of explanted devices was conducted to evaluate the modes and consequences of failure.

RESULTS

Sixty patients were identified with device fatigue, 49 of whom had abdominal endovascular repairs and 11 of whom had thoracic repairs. Of the 60 patients with stent graft fatigue, 43 patients had metallic stent fractures, 14 had suture disruptions, and three had graft holes. These material failures occurred within seven distinct stent graft designs. The average time to the recognition of failure was 19 months, with a mean follow-up period of 8 months since the event was identified. Eleven patients died, and one was lost to follow-up 2 years after identification of a stent fracture. The remaining patients are presently being followed eoyj physical examination, plain film radiograph, and computed tomographic scans for clinical sequelae of device fatigue.

CONCLUSION

Endovascular stent graft fatigue has been recognized in numerous devices after aortic implantation. Fatigue may take the form of stent, graft, or suture failure, with certain modes unique to specific stent graft devices. The clinical significance of stent graft material failure remains uncertain.

Rupture of abdominal aortic aneurysm with tear of inferior vena cava in a patient with prior endograft

We report a case of contained rupture of abdominal aortic aneurysm and tear of the inferior vena cava (IVC) 15 months after placement of an aortic endograft (ANEURX graft, Medtronic, Sunnyvale, Calif). A 63-year-old man with significant coronary artery disease underwent endograft exclusion of abdominal aortic aneurysm with Aneurx graft. The patient was seen with a rupture of the aortic aneurysm, probably caused by poor proximal fixation of the graft associated with separation of the left iliac extension limb from the main body of the graft. Angulated right iliac limb of the stent graft penetrated into the Ivc just above the common iliac junction and caused sealed perforation. Successful repair with aortobiiliac graft reconstruction after removal of the endograft was accomplished. The IVC laceration was repaired. Possible mechanisms of failure of endograft are discussed.

Acute aortic abnormalities

Aneurysm and type B dissections account for most acute abdominal aortic abnormalities. The postsurgical aorta deserves special attention owing to the risk of complications. Most aortic abnormalities presenting acutely are emergencies that carry a high risk of mortality, and imaging plays a critical role in patient evaluation. Modern helical CT scanners provide excellent spatial resolution, are readily available, and allow for rapid imaging. For these reasons, helical CT angiography is the imaging modality of choice for initial evaluation of the acute aorta.

Endovascular repair of an inflammatory abdominal aortic aneurysm complicated by aortoduodenal fistulation with an unusual presentation

Aortoenteric fistulation (AEF) is a well-documented late complication of open abdominal aortic aneurysm (AAA) repair, occurring in between 0.4% and 4% of cases. In the absence of an anastomosis, AEF is likely to be rare after endovascular aneurysm repair (EVAR) and has only recently been described in the literature as a result of mechanical stent failure or migration. We present the case of a 61-year-old man who underwent EVAR for an AAA with a "nonspecific" periaortic inflammatory mass. Six months postoperatively, an AEF developed, presenting with metastatic sepsis followed by septic infective thromboembolization to his right leg, and amputation was necessary. His stent was well positioned and mechanically intact. We emphasize the need for vigilance about the risk of AEF when adopting an endovascular approach to repair the AAA with a nonspecific periaortic inflammatory mass and highlight the need for awareness about the unusual septic manifestations of AEF.

Which factors increase the risk of conversion to open surgery following endovascular abdominal aortic aneurysm repair? The EUROSTAR collaborators

OBJECTIVE

to identify factors that increase the risk of conversion to open surgery following endovascular repair of abdominal aortic aneurysms (AAAs) and to assess their outcome. Design analysis of 1871 patients enrolled in the EUROSTAR collaborators registry.

MATERIALS AND METHODS

patient characteristics, anatomic features of the aneurysm, type of endovascular device, institutional experience and the year in which the procedure was performed were related to risk of conversion.

RESULTS

forty-nine patients (2.6%) required conversion. In 38 patients conversion was performed during the first postoperative month (primary conversions) and in 11 patients during follow-up (secondary conversions). Primary conversion was mostly due to access problems and device migration. Secondary conversions were performed for rupture in six and for a persistent endoleak, with or without aneurysmal growth, in five patients. Patients who were converted were significantly older, had a lower body weight, and had a higher prevalence of chronic obstructive pulmonary disease. Conversion was associated with shorter, wider infrarenal necks and larger aneurysms. The conversion rate was lower when a team had performed more than 30 procedures, and in procedures performed during the last two years of the study period. The conversion rate was higher with EVT or Talent devices. Patients who required primary conversion had an 18% mortality rate, compared to 2.5% mortality in patients without conversion (p<0.01). Secondary conversion was associated with a perioperative mortality of 27%, and when performed for rupture 50%.

CONCLUSION

both primary conversion and secondary conversion for rupture carry a high operative mortality. Awareness of the risk factors may reduce conversion rate as well as early and medium term mortality.

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

Despite satisfying short- and middle-term effectiveness and feasibility, endovascular stent-grafting for abdominal aortic aneurysm is still under evaluation. We report a case of an aortoduodenal fistula after the use of this technique. Enlargement of the upper aneurysmal neck was followed by caudal migration of the major portion of the stent-graft, which resulted in kinking of the device in the aneurysmal sac. Ulcerations were found on adjacent portions of both the aneurysmal sac and the adjacent duodenum. Only the textile portion of the prosthetic contralateral limb separated the aortic lumen from the corresponding duodenal lumen. Early detection of complications after stent-grafting is essential to allow successful treatment, either surgical or endoluminal.