Graft-related complications after abdominal aortic aneurysm repair: reassurance from a 36-year population-based experience

Revascularization and Digestive Tract Repair in Secondary Aortoenteric Fistula Using a Single-Center in Situ Revascularization Strategy

BACKGROUND

Information regarding optimal revascularization and digestive tract repair in secondary aortoenteric fistula (sAEF) remains unclear. Thus, reporting treatment outcomes and presenting comprehensive patient details through a structured treatment approach are necessary to establish a treatment strategy for this rare, complex, and fatal condition.

METHODS

We performed a single-center retrospective review of consecutive sAEF managed based on our in situ revascularization and intestinal repair strategy. The primary endpoint of this study was all-cause mortality, and secondary endpoints were the incidence of in-hospital complications and midterm reinfections.

RESULTS

Between 2007 and 2020, 16 patients with sAEF, including 13 men (81%), underwent in situ revascularization and digestive tract repair. The median follow-up duration for all participants was 36 (interquartile range, 6-62) months. Among the participants, 81% (n = 13), 13% (n = 2), and 6% (n = 1) underwent aortic reconstruction with rifampin-soaked grafts, unsoaked Dacron grafts, and femoral veins, respectively. The duodenum was the most commonly involved site in enteric pathology (88%; n = 14), and 57% (n = 8) of duodenal breaks were repaired by a simple closure. Duodenum's second part-jejunum anastomosis was performed in 43% of patients (n = 6), and 19% of the patients (n = 3) died perioperatively. In-hospital complications occurred in 88% patients (n = 14), and the most frequent complication was gastrointestinal. Finally, 81% patients (n = 13) were discharged home. Oral antibiotics were administered for a median duration of 5.7 months postoperatively; subsequently, the participants were followed up carefully. Reinfection was detected in 6% of the patients (n = 1) who underwent reoperation without any complications. The 1-year and 3-year overall survival rates of participants were 75% (n = 12) and 75% (n = 9), respectively, and no sAEF-related deaths occurred, except perioperative death.

CONCLUSIONS

Surgical intervention with contemporary management based on our vascular strategy and digestive tract procedure may be a durable treatment for sAEF.

Secondary aortoenteric fistula: a narrative review of the view of the surgeon

Aortoenteric fistula (AEF) is defined as the abnormal communication between the aorta and the gastrointestinal tract. AEFs are divided into primary and secondary usually after abdominal aortic aneurysm (AAA) recovery and are a rare but quite dangerous cause of gastrointestinal bleeding that the general surgeon may face during his/her career. Secondary AEF was first described in 1953 to a 44-year-old woman 3 months after an AAA operation. This review presents the role of the surgeon in the management of secondary aortoenteric fistulas. AEFs are a rare but fatal gastrointestinal bleeding cause that the general surgeon may be asked to manage. Diagnosis requires the combination of strong clinical suspicion and the presence of a history of AAA surgery. Although a vascular surgery case, general surgeons play a role in choosing the technique of restoring the intestinal tract, which seems to be significantly related to subsequent morbidity and mortality.

A Modern Series of Secondary Aortoenteric Fistula - A 19-Year Experience

OBJECTIVES

Secondary aortoenteric fistula is a rare and life-threatening condition. Clear evidence on the ideal therapeutic approach is largely missing. This study aims to analyze symptoms, etiology, risk factors, and outcomes based on procedural details.

PATIENTS AND METHODS

All patients with secondary aortoenteric fistula admitted between 2003 and 2021 were included. Patient characteristics, surgical procedure details, and postoperative outcomes were analyzed. Outcomes were stratified and compared according to the urgency of operation and the procedure performed. Descriptive statistics were used. The primary endpoint was in-hospital mortality.

RESULTS

A total of twentytwo patients (68% male, median age 70 years) were identified. Main symptoms were gastrointestinal bleeding, pain, and fever. From the twentytwo patients ten patients required emergency surgery and ten urgent surgery. Emergency patients were older on average (74 vs 63 years, P = .015) and had a higher risk of postoperative respiratory complications (80% vs 10%, P = .005). Primary open surgery with direct replacement of the aorta or an extra-anatomic bypass with an additional direct suture or resection of the involved bowel was performed in sixteen patients. In four patients underwent endovascular bridging treatment with the definitive approach as a second step. Other two patients died without operation (1x refusal; 1x palliative cancer history). In-hospital mortality was 27%, respectively. Compared to patients undergoing urgent surgery, those treated emergently showed significantly higher in-hospital (50% vs 0%, P = .0033) mortalities.

CONCLUSION

Despite rapid diagnosis and treatment, secondary aortoenteric fistula remains a life-threatening condition with 27% in-hospital mortality, significantly increased upon emergency presentation.

Pseudoaneurysms: Different ultrasound patterns, aetiologies and locations

Pseudoaneurysms are frequent vascular anomalies. This review article aims to describe the unique specific aspect of pseudoaneurysm (PSA) that allows to make the diagnosis using different modalities: colour Doppler ultrasound, computed tomographic angiography, magnetic resonance angiography and conventional angiography. It is essential to know the various aetiologies of PSA: iatrogenic, traumatic, dissecting and anastomotic; different locations and the possible complications, information to help clinicians choose the best treatment. Our review is supported by illustrated series of cases.

2022 ACC/AHA guideline for the diagnosis and management of aortic disease: A report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Predictors of Five-Year Survival after EVAR: 10-Year Experience of Single-Center Cohort Study

BACKGROUND

Endovascular abdominal aortic repair (EVAR) is the main therapeutic option for repairing abdominal aortic aneurysms (AAAs). We aimed to determine the long-term outcomes of patients who underwent EVAR at our center.

METHODS

In this retrospective cohort study, patients who underwent EVAR for intact isolated AAA at Tehran Heart Center between 2007 and 2017 were included. Clinical outcomes and the frequency of mortality were analyzed for follow-up periods. We calculated the 5-year survival rate and its predictors for our patients using Kaplan-Meier estimation.

RESULTS

We included the data of all patients (154 patients, mean age = 70.7 [± 8.0] years, 96.1% men) who successfully underwent EVAR at our center. The most common risk factors were coronary artery disease (70.1%), hypertension (68.2%), smoking (64.9%), and dyslipidemia (39.6%). There was no mortality during the procedure. The median follow-up was 65.5 months. An average decrease of 9.07 mm (95% confidence interval: 6.9-11.2) occurred in the size of the AAA. During follow-up, 12 patients developed some complications, 49 died, and 7 did not complete the follow-up. The 5-year survival rate was 75% (3.9%). The independent predictors for 5-year survival were age (hazard ratio [HR] = 1.06, P = 0.002) and anemia (HR = 1.91, P = 0.029). Despite not being statistically significant, dyslipidemia (HR = 0.573, P = 0.078) and long intensive care unit/cardiac care unit stays (HR = 1.08, P = 0.070) were borderline mortality predictors.

CONCLUSIONS

This study depicted an acceptable survival rate for patients who underwent EVAR at our center. Age and anemia, 2 modifiable predictors of 5-year survival, can probably prolong the survival rate of patients, which requires evaluation later.

Silver acetate and Triclosan Antimicrobial Graft Evaluation for surgical Repair of aortic disease (STAGER Study)

BACKGROUND

The aim of this study was to assess perioperative and late performance of a silver acetate and triclosan impregnated antimicrobial vascular graft (Intergard Synergy, Intervascular SAS, La Ciotat, France) during open surgical repair of abdominal aortic aneurysms (AAA), and to compare it with standard polyester grafts ones.

METHODS

This retrospective single-centre study (STAGER Study, clinicaltrials.gov: NCT04557254) included patients undergone non-infectious AAA surgical repair between 2012 and 2019, divided into two groups according to the implanted aortic prosthesis: standard polyester graft (PolyG) and silver-triclosan graft (SynG). Early primary endpoints were 30-day mortality, major adverse events (MAEs), and reintervention rates; late primary endpoints were overall and aortic-related survival, reintervention-free survival, and graft infection rate at a mean follow-up (FU) of 49.4±26.8 months.

RESULTS

Five hundred forty-seven patients were included [PolyG 49%, and SynG 51%]. Both groups were substantially homogeneous in risk factors and demographics. Two patients died within 30 days. In-hospital MAE rate [PolyG 14.2% vs. SynG 10.7%; P=.248] and 30-day reintervention rate were not significantly different [PolyG 2.6% vs. SynG 1.4%; P=.374]. At 5 years, overall survival in the PolyG and SynG groups were 85% and 84%, respectively. Reintervention-free survival was 82% for both groups. Aortic-related survival was 95% and 96%, respectively. Graft infection was observed in 8 (3.3%) PolyG patients and 5 (1.8%) SynG patients.

CONCLUSIONS

Silver acetate and triclosan impregnated grafts demonstrated good early and mid-term results, being considered safe and durable for AAA open repair. Similar graft infection and related death rates were observed compared to polyester standard grafts, supporting non-superiority of one graft over the other.

Aortoiliac graft-enteric fistula presenting as gastrointestinal hemorrhage: A report on a complex case management

Key Clinical Message

Iliac artery-enteric fistula is a rare cause of lower GI bleeding and can cause life-threatening consequences. A high degree of clinical suspicion is needed in patients with previous aortic surgery to allow early multidisciplinary intervention.

Abstract

This case study discusses the staged management of a 78-year-old patient presenting with life-threatening lower gastrointestinal (GI) bleeding secondary to an aortoiliac graft-enteric fistula (GEF) into the sigmoid colon on the background of an adenocarcinoma and diverticular disease. The patient had an aorto bi-iliac synthetic dacron graft repair of an abdominal aortic aneurysm (AAA) some 20 years ago. Here, we present a case of successful endovascular treatment of massive hemorrhage as a bridge to definitive second-stage dacron graft explant and autologous vein reconstruction with a simultaneous anterior resection.

Digestive hemorrhage and fever as a result of a double secondary aortoenteric fistula following the repair of a juxtarenal abdominal aortic aneurysm and an infection of the aortobifemoral bypass graft: a case report

A double secondary aortoenteric fistula (AEF) occurs in a patient who has had significant aortic surgery and is characterized by a direct connection between the gastrointestinal (GI) tract and the aorta at two separate sites.

IMPORTANCE

During aortoc reconstructive surgery, the patient may present with a variety of unusual complaints, including fever and GI bleeding. These symptoms are indicative of problems, including the development of an aortoentric fistula, particularly when there is a double secondary fistula.

CASE PRESENTATION

The patient was admitted to the hospital due to hematemesis, melena, and high-grade fever after undergoing synthetic grafting aortobifemoral bypass (anatomical reconstruction) and partial resection of the juxtarenal abdominal aortic aneurysm. Pus discharge and a double aortoenteric fistula in unusual sites such as the second-third portion of the duodenum and caecum are visible in upper GI endoscopy and computed tomography angiography. The patient underwent a two-stage open surgery, the first stage involving aortic limb graft exclusion and extra anatomical reconstruction, and the second stage involving graft removal, fistula management, and bowel repair. Then the patient spent a few days in the surgical intensive care unit before being discharged.

CLINICAL DISCUSSION

Primary and secondary AEF are the two categories of AEF. In patients who underwent aortic reconstruction surgery, the frequency of secondary AEF ranges from 0.36 to 1.6%. Due to the 8:1 injury ratio in the secondery AEF, men suffer more injuries than women.There are two types of fistula depending on whether or not the suture line is involved. The first form is graft enteric erosion, which excludes the suture line, while the second type is entric graft fistula, where the suture line is included. Most common site fistula is third and fourth part of duodenum and least common site is fistula formation in large bowel.

CONCLUSIONS

An uncommon complication is double secondary AEF following aortic reconstruction surgery. Since one of the most significant presentations an AEF patient can present with is major GI bleeding and sepsis, A delay in seeking immediate medical treatment could result in the patient's death. It should be emphasized that one of the mechanisms for AEF formation and a frequent cause of sepsis in patients is recurrent aortic graft infection following aortic reconstruction surgery.

"Redo" 2D-3D Fusion Technique during Endovascular Redo Aortic Repair

PURPOSE

The present study aims to describe a new 2D-3D fusion registration method in the case of endovascular redo aortic repair and compare the accuracy of the registration using the previously implanted devices vs. bones as landmarks.

MATERIALS AND METHODS

This single-center study prospectively analyzed all the patients that underwent elective endovascular re-interventions using the Redo Fusion technique between January 2016 and December 2021 at the Vascular Surgery Unit of the Fondazione Policlinico Universitario A. Gemelli (FPUG)-IRCCS in Rome, Italy. The fusion overlay was performed twice, first using bone landmarks (bone fusion) and the second using radiopaque markers of a previous endovascular device (redo fusion). The pre-operative 3D model was fused with live fluoroscopy to create a roadmap. Longitudinal distances between the inferior margin of the target vessel in live fluoroscopy and the inferior margin of the target vessel in bone fusion and redo fusion were measured.

RESULTS

This single-center study prospectively analyzed 20 patients. There were 15 men and five women, with a median age of 69.7 (IQR 42) years. The median distance between the inferior margin of the target vessel ostium in digital subtraction angiography and the inferior margin of the target vessel ostium in bone fusion and redo fusion was 5.35 mm and 1.35 mm, respectively (p ≤ 0.0001).

CONCLUSIONS

The redo fusion technique is accurate and allows the optimization of X-ray working views, supporting the endovascular navigation and vessel catheterization in case of endovascular redo aortic repair.

A Case Series of Secondary Aortoenteric Fistula after Open Aortic Aneurysm Repair: Timing and Technique of Surgery

Secondary aortoenteric fistula (sAEF) is a rare but serious complication after open aortic aneurysm repair (OAR). Although there is no consensus on the treatment strategy for sAEF, acute management of bleeding and infection control greatly affect the outcome. We report five cases of sAEF following OAR from 2016 to 2021. One patient died of sepsis following graft infection, whereas the others had relatively good outcomes. No recurrence of infection or fistula has been observed over an average follow-up period of 29.8 months. Timely management of bleeding and infection with surgical intervention resulted in favorable outcomes in our patients.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate. Structure: Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Long-Term Results of Complex Abdominal Aortic Aneurysm Open Repair

This study investigated the long-term outcomes of patients treated with open surgical repair for complex abdominal aortic aneurysms (c-AAAs). A total of 119 patients with c-AAAs undergoing repair between January 2010 and June 2016 in a high-volume aortic center were included. The long-term imaging follow-up consisted of yearly abdominal ultrasound examinations and 5-year computed tomography angiography. At a median follow-up of 76 months (IQR 38 months), forty-three deaths (37%) and three (2.5%) aortic-related deaths were observed. Long-term chronic renal decline was observed in fifty (43.8%) patients, significantly correlated with post-operative acute kidney injury. During the follow-up, five reinterventions (4.3%) were performed. The present study suggests that open c-AAA repair can be performed with acceptable operative risk with durable results. To achieve the best possible long-term outcome, the open surgery repair of complex AAA should be performed in high-volume aortic centers and tailored to the patient.

Mid-Term Results of Fenestrated Endovascular Repair after Prior Open Aortic Reconstruction

This study aims to assess the mid-term results of fenestrated endovascular aneurysm repair (FEVAR) for the treatment of proximal aortic pathology after previous open surgical repair (OSR). All patients with a previous history of OSR of an abdominal aortic aneurysm undergoing a FEVAR procedure between October 2010 and November 2021 were included. The endpoints of the study were technical success, mortality, target vessel patency and reinterventions during follow-up. Thirty-five patients (34 male, mean age 72.9 ± 7 years) were included. The median interval from the primary surgery to the FEVAR procedure was 136 months (range 47–261). The indication for treatment was a para-anastomotic aneurysm in 18 (51%) patients and a true aneurysm due to progression of disease in 17 (49%) patients. Technical success was achieved in 33 (94%) patients. There was one (3%) early death due to postoperative bleeding from a renal artery. Estimated survival at 12, 24 and 36 months was 89.1% ± 6%, 84.4% ± 7.3% and 84.4% ± 7.3%, respectively. There was no aneurysm-related mortality. One (3%) target vessel occluded during follow-up and three (9%) patients underwent late reinterventions. In conclusion, FEVAR is a safe and effective alternative for the endovascular treatment of para-anastomotic aneurysms/pseudoaneurysms after OSR showing high technical success, low mortality and morbidity, and good mid-term outcomes.

Out of sight for the endoscopist? Gastrointestinal bleeding after aortic repair

BACKGROUND AND STUDY AIM

Secondary Aortoenteric Fistulas (sAEF) are difficult to diagnose and usually result in fatal gastrointestinal (GI) bleeding following aortic repair. Outcomes are largely dependent on a timely diagnosis, but AEFs remain challenging to identify endoscopically and are usually diagnosed on computed tomography (CT) scans. The aim of our study was optimize diagnosis of AEF by identifying patients developing GI bleeding after aortic repair, investigate their clinical course and identify factors specific to different bleeding sources.

METHODS

A retrospective, single-center study capturing all patients developing upper or lower GI bleeding after aortic surgery between January 2009 and March 2020 was performed. Electronic health records were screened for diagnostic codes of the relevant procedures. Bleeding was classified into three groups: AEF with demonstrable fistula, ischemic - macroscopic ulceration plus histological confirmation or imaging and "other" due to other recognized conventional cause, such as peptic ulcer disease.

RESULTS

47 GI bleeding episodes in 39 patients were identified. Of these, 10 episodes (21%) were caused by AEF, 16 (34%) by ischemic ulceration and 21 (45%) due to other causes. Patients with AEF exhibited more frequent hemodynamic instability requiring vasopressors and had higher mortality, while ischemic ulcerations were associated with more recent operation or hypotensive episode.

CONCLUSIONS

GI bleeding complications are uncommon following aortic surgery. AEF and ischemic ulceration are however frequent bleeding causes in this cohort. In patients presenting with fulminant bleeding, primary CT-scanning should be considered.

Closed-Loop Bowel Obstruction Years After an Open Abdominal Aortic Aneurysm Repair

A 68-year-old male has a significant past medical history of severe aortic stenosis, peripheral arterial disease, chronic kidney disease, and an abdominal aortic aneurysm treated with a bifurcated interposition aortobiiliac graft. He was admitted to the hospital for an elective one-vessel coronary artery bypass graft and placement of a bioprosthetic aortic valve. Postoperatively, he developed worsening abdominal pain, leukocytosis, and inability to tolerate nutrition by mouth. Computed tomography revealed moderately dilated loops of the small bowel with two transition points in the right lower quadrant. He was taken emergently to the operating room for an exploratory laparotomy, and a 28-cm necrotic jejunal loop was entrapped posterior to the right iliac segment of the graft. In a patient with an intra-abdominal synthetic vascular graft, a closed-loop bowel obstruction caused by entrapment by the vascular graft is exceptionally rare; however, it should be considered in the presence of bowel obstruction.

Adjuncts to the Management of Graft Aorto-Enteric Erosion and Fistula with in situ Reconstruction

OBJECTIVE

The objective of this retrospective single centre study was to determine whether different enteric reconstruction methods and adjuncts confer a benefit after in situ reconstructions (ISRs) of graft aorto-enteric erosion (AEnE) and fistula (AEnF).

METHODS

Primary endpoints were in hospital mortality and AEnE/F recurrence. Survival was estimated using the Kaplan-Meier method and explanatory factors were searched for using uni- ± multivariable Cox regression analysis. In 2013, a multidisciplinary team meeting was convened and since then the primary operator has always been a senior surgeon.

RESULTS

Sixty-six patients were treated for AEnE (n = 38) and AEnF (n = 28, 42%) from 2004 to 2020. All patients with AEnF presented with gastrointestinal bleeding (vs. 0 for AEnE; p < .001). Signs of infection were seen in 50 patients (76% [37 for AEnE vs. 13 for AEnF]; p < .001). Referrals for endograft infection increased over time (n = 15, 23%; one before 2013 vs. 14 after; p = .002). Most patients underwent complete graft excision (n = 52, 79%) with increasing suprarenal cross clamping (n = 21, 32%; four before 2013 vs. 17 after; p = .015). Complex visceral reconstructions decreased over time (n = 31, 47%; 17 before 2013 vs. 14 after; p = .055), while "open abdomens" (OAs) increased (one before 2013 vs. 22 after; p < .001), reducing operating time (p = .012). In hospital mortality reached 42% (n = 28). Estimated survival reached 47.6% (95% confidence interval [CI] 35.0 - 59.1) at one year and 45.6% (95% CI 33.0 - 57.3) at three years and was higher for AEnE than for AEnF (log rank p = .029). AEnE/F recurrence was noted in 12 patients (18%). Older age predicted in hospital mortality in multivariable analysis (p = .034). AEnE/F recurrence decreased with the presence of a primary senior surgeon (vs. junior; p = .003) and OA (1 [4.4%] vs. 11 [26%] for primary fascial closure; p = .045) in univariable analysis.

CONCLUSION

Mortality and recurrence rates remain high after ISR of AEnE/F. Older age predicted in hospital mortality. Primary closure of enteric defects ≤ 2 cm in diameter reduced operating time without increasing the recurrence of AEnF.

A Rare Case of Abdominal Aortic Aneurysm with Ureteral Compression

Introduction: In this report, we present a rare case of aortic aneurysm with associated left ureter obstruction and consequent hydronephrosis.

Case presentation: A 62-year-old man was admitted for epigastric and periumbilical pain, extended in the spine, and anuria. As for associated diseases, he presented arterial hypertension stage II/III, chronic ischemic cardiomyopathy, acidosis, hyperpotassemia, spondylosis with radiculopathy, acute renal failure, renal lithiasis, and eating difficulties. After performing a CT scan, the patient was diagnosed with giant abdominal infrarenal aortic aneurysm with ureter compression, and retroperitoneal rupture with common and internal iliac arteries occlusion. We performed a xifo-pubian laparotomy with endoaneurysmorrhaphy and aortoiliac bilateral bypass using silver Dacron vascular prosthesis (16 × 8 mm in diameter). Douglas drainage was necessary, ending with laparoraphy. The patient presented a favorable postoperative evolution.

Conclusion: Open surgery remains the gold standard method of treatment for large aortic aneurysms, given the inability of endovascular procedures to solve problems caused by compression.

The retroperitoneal approach for contemporary open abdominal aortic aneurysm surgery: The anatomical reasoning

In current practice, the place of open surgery in managing abdominal aortic aneurysm is a contentious issue. The principal reason being greater applications of endovascular techniques treating increasingly complicated aortic disease. Development of branched and fenestrated devices enabled this, with numbers increasing annually. This meant a good risk patient with a long infrarenal aortic neck and normal diameter non-tortuous iliac arteries may be suitable for both endovascular and open techniques. However, indications for open surgery are becoming increasingly unclear nowadays due to short-term gains in morbidity and mortality. Exact aortic anatomical morphologies optimum for open or endovascular techniques remains unclear. As graft technology evolves, possibilities for endovascular options are expanding. Currently, establishing optimum treatment plans for complicated abdominal aortic aneurysm (little or no infrarenal neck) is difficult without considering general fitness of the patient. Hence, two sets of possible postoperative complications and follow-up protocols must be explained to patients before either approach. Complicating matters is the optimum surgical approach used for any open repair. The standard approach for open abdominal aortic aneurysm surgery has been transperitoneal as this provides excellent access to the infrarenal aorta and iliac arteries. However, although less commonly used, the retroperitoneal approach has advantages particularly when location of proximal aortic disease indicates suprarenal clamp might be optimum. This paper scrutinises benefits of the retroperitoneal approach performed purely for anatomical reasons where stent graft may be considered complicated. Also, long-term outcomes are examined in terms of endo-leak and subsequent development of true and false aneurysm following both endovascular and open repair.

Prosthetic vascular graft infection: A systematic review and meta-analysis on diagnostic accuracy of 18FDG PET/CT

INTRODUCTION

There is a high risk of mortality and morbidity associated with Vascular Graft Infections (VGI) which requires early diagnosis. The aim of the present systematic review and meta-analysis was to evaluate the diagnostic accuracy, sensitivity and specificity of 18FDG PET/CT in diagnosing VGI.

METHODS

A systematic review was conducted according to the PRISMA guidelines through a search in Embase, PubMed, and Cochrane databases. We evaluated five parameters including specificity, sensitivity, negative and positive predictive values (NPV and PPV), and accuracy. We used STATA/MP 15.0 (StataCorp, College Station, TX) for all of our analyses.

RESULTS

Overall 10 studies including 320 patients undergone 18FDG PET/CT were included. The sensitivity, specificity, positive and negative likelihood ratios along with their 95% CI were 0.92 (95% CI 0.88-0.95), 0.76 (95% CI 0.76-0.70), 3.49 (95% CI 3.49-2.32) and 0.14 (95% CI 0.09-0.23), respectively. The diagnostic odds ratio (DOR) for diagnosis of VGI was 37.12 (95% CI 14.84-92.82). The mean cut-off value of the maximum standardized uptake value (SUVmax) for diagnosis of VGI was 5.39 while the overall mean SUVmax among patients with VGI was 8.47.

CONCLUSION

According to our results, 18FDG PET/CT is a useful diagnostic method in detecting active VGI with high diagnostic accuracy. Because of its ability to evaluate morphology and main texture using SUVmax, the 18FDG PET/CT provides an objective assessment of aspects and extent of disease activity, which results in preventing unnecessary surgery, proper treatment planning, and evaluating the effectiveness of treatment.

Improved perioperative mortality after secondary aorto-enteric fistula repair and lessons learned from a 20-year experience

BACKGROUND

Secondary aorto-enteric fistulas (SAEFs) are rare but represent one of the most challenging and devastating problems for vascular surgeons. Several issues surrounding SAEF treatment remain unresolved, including optimal surgical reconstruction and conduit choice. We performed an audit of our experience with SAEFs and highlight aspects of care that have affected outcomes over time with the intent to identify factors associated with best outcomes.

METHODS

We performed a single center, retrospective review of all consecutive SAEF repairs (1999-2019), defined as presence of a false communication between an enteric structure and pre-existing aortic graft. The primary endpoint was 30-day mortality. Secondary endpoints included incidence of complications and overall survival. Time-dependent outcome comparison was performed. Cox proportional hazards modeling and life-table analysis estimated risk and freedom from endpoints.

RESULTS

A total of 57 patients (63% male; n = 36) presented with SAEF (median age, 69 years; interquartile range [IQR], 61-74 years). Median follow-up time was 10 months (interquartile range, 3-21 months. The most common presenting symptoms were gastrointestinal bleeding (60%; n = 34) and abdominal pain (56%; n= 3 2). For the overall cohort, 30% (n = 17) underwent extra-anatomic bypass with aortic ligation, 30% (n = 17) rifampin-soaked Dacron graft, 26% (n = 15) femoral vein (eg, neoaortoiliac system), and 14% (n = 8) cryopreserved aortic allograft. The enteric communication involved the duodenum in 85% (n = 48), and a double-layer hand-sewn primary repair was most commonly employed (61%; n = 35). Thirty-day mortality was 35% (n = 20) with no significant difference between 90 days (39%; n = 22) and 180 days (42%; n = 24). Morbidity was 70% (n = 40), with gastrointestinal (30%; n = 17; leak [9%]), pulmonary (25%; n = 14), and renal (21%) complications being most common. Incidence of reoperation for any vascular and/or gastrointestinal-related complication was 56% (n = 32). One-year and 3-year survival was 54% ± 6% and 48% ± 8%, respectively. Over time, 30- and 90-day mortality improved (odds ratio, 0.1; 95% confidence interval, 0.4-0.5; P = .002) despite no change in patient factors, operative strategy, conduit choice, or morbidity rate. Prehospital history of gastrointestinal bleeding was associated with worse survival (hazard ratio, 2.0; 95% confidence interval, 1.0-3.9; P = .06); however, reconstruction strategy (in-situ vs extra-anatomic bypass), postoperative gastrointestinal and/or vascular complication, omental flap use, and preoperative endovascular aneurysm repair history were not associated with outcome.

CONCLUSIONS

In conclusion, we observed improved short-term mortality despite no significant change in patient presentation or postoperative complications. This highlights increasing institutional experience in selecting the optimal surgical strategy and improved ability to rescue patients experiencing adverse postoperative events. An individualized approach to reconstruction and conduit choice can lead to best outcomes after SAEF management when patients are treated at a high-volume aortic surgery center.

Impact of unknown incidental findings in PET/CT examinations of patients with proven or suspected vascular graft or endograft infections

Vascular graft or endograft Infections (VGEI) are rare but severe complications of vascular reconstructive surgery, and associated with significant mortality and morbidity risk. Positron emission tomography/computed tomography with ¹⁸F-fluorodeoxyglucose (PET/CT) has been shown to have a high diagnostic accuracy in the detection of VGEI. In this single-center prospective cohort study, we assessed the rate and the impact on patient management of relevant unknown incidental findings in PET/CT of patients with proven or suspected VGEI, and clinical follow-up of all patients was performed. Our study results show a comparably high rate of relevant unknown incidental findings (181 in 502 examinations), with documented direct impact on patient management in 80 of 181 (44%) of all findings. PET/CT scan- and patient-based evaluation revealed impact on patient management in 76 of 502 (17%) of all PET/CT scans, and in 59 of 162 (36%) of all patients, respectively. Furthermore, PET/CT correctly identified the final diagnosis in 20 of 36 (56%) patients without VGEI. In conclusion, in proven and suspected VGEI, PET/CT detects a high rate of relevant unknown incidental findings with high impact on patient management.

Local Repair of a Secondary Aortoenteric Fistula in an Unstable Patient in a Resource-Poor Setting: A Case Report and Literature Review

The presentation of a massive upper gastrointestinal bleed (UGIB) due to an aortoenteric fistula (AEF) is a rare occurrence. A high index of suspicion is required to rapidly make the diagnosis and execute prompt surgical management. Despite the many surgical options described, the survival rate continues to be low. Conventional surgical management is associated with a high morbidity and mortality. However, in emergencies, patients are unsuitable for major vascular surgery and may benefit from the less invasive staged procedure. This is a case report of a secondary aortoenteric fistula (SAEF) presenting as a massive UGIB, two years after an abdominal aortic aneurysm repair using a Dacron graft. Due to a lack of endovascular service in our setting, we proceeded with an upper gastrointestinal endoscopy followed by exploratory laparotomy. A damage control approach was chosen for our patient, i.e., local repair of the graft and aorta, as our patient was on double inotropes on the table. The patient died within 24 hours as a result of massive blood volume loss.

Case series of aortoenteric fistulas: a rare cause of gastrointestinal bleeding

BACKGROUND

Aortoenteric fistula (AEF) is a rare cause of gastrointestinal bleeding and is often misdiagnosed in clinical practice. Herein, a case series of AEFs are presented and the clinical characteristics, diagnosis, and management strategies are summarized.

METHODS

A retrospective analysis was performed on consecutive hospitalized patients with a final diagnosis of AEF at Beijing Friendship Hospital, Capital Medical University, between January 1, 2007 and March 31, 2020. The clinical data including diagnostic and management procedures as well as outcomes were collected and summarized.

RESULTS

A total of nine patients were included in this study, five with primary AEF and four with secondary AEF. Eight of the patients were male, and the median age was 63 years. The fistulas were located in both the small intestine and the colon. All patients presented with gastrointestinal bleeding and pain, followed by weight loss, anorexia, and fever. A typical abdominal triad was found in only two cases. Seven patients experienced complications with preoperative abdominal infections and sepsis, and multiple organ failure occurred in four of these patients. All patients were assessed by computed tomography and five underwent abdominal and/or iliac aorta angiography. Two of these patients showed contrast agent leakage from the abdominal aorta into the intestine. Two cases were diagnosed with AEF by endoscopy before the operation. Eight patients received surgery and six patients survived.

CONCLUSIONS

AEF is a rare cause of gastrointestinal bleeding that is associated with high mortality. Gastrointestinal bleeding and pain are the most common presentations. Timely diagnosis and multidisciplinary management are crucial to achieve a positive outcome.

Considerations in the Development of Small-Diameter Vascular Graft as an Alternative for Bypass and Reconstructive Surgeries: A Review

BACKGROUND

Current design strategies for small diameter vascular grafts (< 6 mm internal diameter; ID) are focused on mimicking native vascular tissue because the commercially available grafts still fail at small diameters, notably due to development of intimal hyperplasia and thrombosis. To overcome these challenges, various design approaches, material selection, and surface modification strategies have been employed to improve the patency of small-diameter grafts.

REVIEW

The purpose of this review is to outline various considerations in the development of small-diameter vascular grafts, including material choice, surface modifications to enhance biocompatibility/endothelialization, and mechanical properties of the graft, that are currently being implanted. Additionally, we have taken into account the general vascular physiology, tissue engineering approaches, and collective achievements of the authors in this area. We reviewed both commercially available synthetic grafts (e-PTFE and PET), elastic polymers such as polyurethane and biodegradable and bioresorbable materials. We included naturally occurring materials by focusing on their potential application in the development of future vascular alternatives.

CONCLUSION

Until now, there are few comprehensive reviews regarding considerations in the design of small-diameter vascular grafts in the literature. Here-in, we have discussed in-depth the various strategies employed to generate engineered vascular graft due to their high demand for vascular surgeries. While some TEVG design strategies have shown greater potential in contrast to autologous or synthetic ePTFE conduits, many are still hindered by high production cost which prevents their widespread adoption. Nonetheless, as tissue engineers continue to develop on their strategies and procedures for improved TEVGs, soon, a reliable engineered graft will be available in the market. Hence, we anticipate a viable TEVG with resorbable property, fabricated via electrospinning approach to hold a greater potential that can overcome the challenges observed in both autologous and allogenic grafts. This is because they can be mechanically tuned, incorporated/surface-functionalized with bioactive molecules and mass-manufactured in a reproducible manner. It is also found that most of the success in engineered vascular graft approaching commercialization is for large vessels rather than small-diameter grafts used as cardiovascular bypass grafts. Consequently, the field of vascular engineering is still available for future innovators that can take up the challenge to create a functional arterial substitute.

Surgical and medical interventions for abdominal aortic graft infections

BACKGROUND

Abdominal aortic graft infections are a major complication following abdominal aortic aneurysm surgery, with high morbidity and mortality rates. They can be treated surgically or conservatively using medical management. The two most common surgical techniques are in situ replacement of the graft and extra-anatomical bypass. Medical management most commonly consists of a course of long-term antibiotics. There is currently no consensus on which intervention (extra-anatomical bypass, in situ replacement, or medical) is the most effective in managing abdominal aortic graft infections. Whilst in emergency or complex situations such as graft rupture surgical management is the only option, in non-emergency situations it is often personal preference that influences the clinician's decision-making.

OBJECTIVES

To assess and compare the effects of surgical and medical interventions for abdominal aortic graft infections.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases and WHO ICTRP and ClinicalTrials.gov trials registers to 2 December 2019. We also reviewed the bibliographies of the studies identified by the search and contacted specialists in the field and study authors to request information on any possible unpublished data.

SELECTION CRITERIA

We aimed to include all randomised controlled trials that used surgical or medical interventions to treat abdominal aortic graft infections. The definitions of abdominal aortic graft infections were accepted as presented in the individual studies, and included secondary infection due to aortoenteric fistula. We excluded studies presenting data on prosthetic graft infections in general, unless data specific to abdominal aortic graft infections could be isolated.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed all studies identified by the search. We planned to independently assess risk of bias of the included trials and to evaluate the quality of the evidence using the GRADE approach. Our main outcomes were overall mortality, amputation, graft re-infection, overall graft-related complications, graft-related mortality, acute limb ischaemia, and re-intervention.

MAIN RESULTS

We identified no randomised controlled trials to conduct meta-analysis.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to draw conclusions to support any treatment over the other. Multicentre clinical trials are required to compare different treatments for the condition.

Impact of Gradual Adoption of EVAR in Elective Repair of Abdominal Aortic Aneurysm: A Retrospective Cohort Study from 2009 to 2015

INTRODUCTION

The recommendations about the preferred type of elective repair of abdominal aortic aneurysm (AAA) still divides guidelines committees, even nowadays. The aim is to assess outcomes after AAA repair focusing on differences between endovascular aneurysm repair (EVAR) and open surgical repair (OSR).

METHODS

The observational retrospective cohort study of consecutive patients submitted to elective AAA repair at a tertiary center, 2009-2015. Exclusion criteria were as follows: nonelective cases or complex aortic aneurysms. Primary outcomes were postoperative complications, length of hospital stay, survival, freedom from aortic-related mortality, and vascular reintervention. Time trends were assessed along the period under analysis.

RESULTS

From a total of 211 included patients, those submitted to EVAR were older (74 ± 7 vs. 67 ± 9 years; P < 0.001), presented a higher prevalence of hypertension (83.5% vs. 68.5%, P = 0.004), obesity (28.7% vs. 14.3%, P = 0.029), previous cardiac revascularization (30.5% vs. 14.7%, P = 0.005), heart failure (17.2% vs. 5.2%, P = 0.013), and chronic obstructive pulmonary disease (32.8% vs. 13.3%, P = 0.002). Patients were followed during a median of 49 months. EVAR resulted in a significantly shorter length of hospital stay (median 4 and interquartile range 3 vs. 8 (9); P < 0.001), lower 30-day complications (10.6% vs. 22.8%, P = 0.017), lower aortic-related mortality, and similar reintervention after adjustment with a propensity score. Along the time under analysis, EVAR became the predominate type of repair (P = 0.024), the proportion of complications decreased (P = 0.014), and the 30-day mortality (P = 0.035).

CONCLUSIONS

Although EVAR was offered to patients with more comorbidities, better and durable outcomes were achieved after EVAR, favoring its adoption for elective AAA repair.

Emergency Endovascular Aneurysm Repair Coupled with Staged Omentopexy for Primary Aorto-Duodenal Fistula

A primary aorto-duodenal fistula (ADF), a rare, spontaneous development of a communication between the aorta and duodenum, is a disastrous complication of an abdominal aortic aneurysm. A 73-year-old patient with primary ADF underwent emergent endovascular aneurysm repair (EVAR), followed by staged omentopexy, without removing a stent graft (SG). The patient received long-term treatment with antibiotics, and there has been no evidence of infection during a follow-up period of three years. Emergency EVAR coupled with omentopexy, may be a treatment option for primary ADF, even when it means leaving the SG in a potentially infectious site.

In situ revascularization with rifampicin-soaked silver polyester graft for aortic infection: Results of a retrospective monocentric series of 18 cases

OBJECTIVE

To evaluate the short and long-term results of in situ prosthetic graft treatment using rifampicin-soaked silver polyester graft in patients with aortic infection.

MATERIAL AND METHOD

All the patients surgically managed in our center for an aortic infection were retrospectively analyzed. The primary endpoint was the intra-hospital mortality, secondary outcomes were limb salvage, persistent or recurrent infection, prosthetic graft patency, and long-term survival.

RESULTS

From January 2004 to December 2015, 18 consecutive patients (12 men and 6 women) were operated on for aortic infection. Six mycotic aneurysms and 12 prosthetic infections, including 8 para-entero-prosthetic fistulas, were treated. In 5 cases, surgery was performed in emergency. During the early postoperative period, we performed one major amputation and two aortic infections were persistent. Intra-hospital mortality was 27.7%. The median follow-up among the 13 surviving patients was 26 months. During follow-up, none of the 13 patients presented reinfection or bypass thrombosis.

CONCLUSION

This series shows that in situ revascularization with rifampicin-soaked silver polyester graft for aortic infection have results in agreement with the literature in terms of intra-hospital mortality with a low reinfection rate.

Aortoenteric Fistula through a Thrombosed Graft

Patient: Male, 75-year-old

Final Diagnosis: Aortoenteric fistula through a thrombosed graft

Symptoms: Hematochezia • melena

Medication:—

Clinical Procedure: Excision of the aortic graft, pyloric exclusion and loop gastrojejunostomy

Specialty: Surgery

Endovascular treatment of para-anastomotic aneurysms after open abdominal aortic surgery

INTRODUCTION

The repair of long-term complications of open abdominal aortic repair such as para-anastomotic aneurysm (PAA) and pseudoaneurysm (PSA) is very challenging. The aim of this study was to assess the outcomes of endovascular repair of PAA/PSA after previous open aortic surgery for aneurismal or occlusive disease.

EVIDENCE ACQUISITION

A systematic review was undertaken; a search was performed (PRISMA) in MEDLINE, CENTRAL, Cochrane databases and key references of all studies of endovascular treatment of PAA/PSA after open aortic surgery.

EVIDENCE SYNTHESIS

Eighteen studies included totally 433 patients (86.3% males) with mean age of 71±2.5 years were identified. Most of the patients were asymptomatic (76%) and diagnosed with PAA (60.5%), while 81.6% had history of open aortic reconstruction for aneurismal disease. The mean diameter of para-anastomotic aneurysms was 59.7 mm (from 23 mm to 110 mm) and the mean duration until their diagnosis was 10±2 years. Standard bifurcated (23.7%), fenestrated (23.4%) and aorto-uni-iliac stent-grafts (16.3%) were mostly used. The technical success rate was 97.8% (391/400) with 1.4% (6/433) 30 day-mortality rate and mean hospital stay of 6±3 days. The mean 1- and 2- year survival rate was 87.8% and 78.8%, respectively. The follow-up ranged from 9 to 43 months, with presenting complications such as endoleak type I (24/378; 6.3%), type II (15/354; 4.3%), type III (3/378;0.8%), migration (4/378; 1%) and limb occlusion (5/310;1.6%). Additionally, 5.7% (19/332) of the patients underwent open conversion, while the total re-intervention rate was 11.4% (39/340; time of reintervention ranged from 7 to 30 months). In cases in which a stent was used for splanchnic vessels (renal artery: 188, superior mesenteric artery: 98, celiac artery: 64), the primary patency rate was 97.4% (341/350).

CONCLUSIONS

Endovascular treatment of PAAs and PSAs after previous open aortic surgery is a feasible and efficient option with high technical success rate, low 30-day mortality and good mid-term outcomes.

Aortoenteric fistulas: spectrum of MDCT findings

An aortoenteric fistula is an abnormal communication between the aorta and the gastrointestinal tract wall. The high mortality associated with this rare entity means it requires early accurate diagnosis. Aortoenteric fistulas are classified as primary when they develop on a native aorta that has not undergone an intervention and as secondary when they develop after vascular repair surgery. All radiologists need to be able to recognize the direct and indirect signs that might suggest the presence of an aortoenteric fistula. This article reviews the types of aortoenteric fistulas and their clinical and pathophysiological correlation, as well as the diagnostic algorithm, illustrating the most characteristic findings on multidetector computed tomography.

Aortic reconstruction in infected aortic pathology by femoral vein "neo-aorta"

The use of autologous femoral veins for in situ reconstruction of the aortoiliac segment is an effective technique to treat native aorta or prosthetic graft infections. The indications, technical details, and outcomes of this procedure are detailed. Graft infection involving the aortic segment, while rare, remains one of the most challenging vascular surgery conditions to treat. The original technique of "neo-aortoiliac surgery" with in situ autologous vein grafts has evolved over the past 25 years and remains a worthwhile alternative for the treatment of aortic graft infections, with lower mortality rates compared with other extra-anatomic or in situ surgical options. Acceptance of this surgical option is due to low graft re-infection rates, rare graft disruption, and low long-term aneurysmal degeneration. Excision of the femoral veins is associated with acceptable rates of lower limb edema. The use of an autologous femoral vein graft can be considered the standard of care in selected patients for the management of aortic graft infections. Optimal management of patients with aortic graft infections requires consideration of all potential therapeutic options because no single modality can be used, and individualizing treatment according to the clinical condition will yield the best patient outcomes.

A systematic review and meta-analysis of 18F-fluorodeoxyglucose positron emission tomography or positron emission tomography/computed tomography for detection of infected prosthetic vascular grafts

OBJECTIVE

The purpose of this investigation was to evaluate the diagnostic accuracy of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET) or PET/computed tomography (PET/CT) for the detection of vascular prosthetic graft infection (VPGI) using a diagnostic accuracy test.

METHODS

The MEDLINE/PubMed and Embase databases, from the earliest available date of indexing through March 31, 2018, were searched for results investigating the diagnostic accuracy of ¹⁸F-FDG PET or PET/CT for the detection of VPGI. We calculated the pooled sensitivities and specificities of included studies, calculated positive and negative likelihood ratios, and obtained summary receiver operating characteristic curves.

RESULTS

Across 10 studies (286 patients), the pooled sensitivity was 0.96 (95% confidence interval [CI], 0.89-0.98) without heterogeneity (I² = 40.2; 95% CI, 0.0-84.4; P = .09), and pooled specificity was 0.74 (95% CI, 0.67-0.81) without heterogeneity (I² = 39.9; 95% CI, 0.0-84.3; P = .09). Likelihood ratio syntheses showed an overall positive likelihood ratio of 3.7 (95% CI, 2.9-4.9) and negative likelihood ratio of 0.06 (95% CI, 0.02-0.15). The pooled diagnostic odds ratio was 63 (95% CI, 23-173). The hierarchical summary receiver operating characteristic curve showed the area under the curve to be 0.87 (95% CI, 0.83-0.89).

CONCLUSIONS

This study showed the high sensitivity and moderate specificity of ¹⁸F-FDG PET or PET/CT for the detection of VPGI. The clinical usefulness of ¹⁸F-FDG PET or PET/CT for detection of VPGI should be validated through further large multicenter studies.

Secondary aortoenteric fistula possibly associated with continuous physical stimulation: a case report and review of the literature

BACKGROUND

Secondary aortoenteric fistula is a rare but fatal complication after reconstructive surgery for an aortic aneurysm characterized by abdominal pain, fever, hematochezia, and hematemesis, and the mortality rate is high. It has been suggested that it arises due to either continuous physical stimulation or prosthesis infection during primary surgery. We describe an aortoenteric fistula following reconstructive surgery for an abdominal aortic aneurysm together with postmortem pathological findings.

CASE PRESENTATION

A 59-year-old Japanese man who had undergone reconstructive surgery for an abdominal aortic aneurysm 20 months earlier presented with the chief complaint of hematochezia and malaise. Esophagogastroduodenoscopy and total colonoscopy revealed only colon diverticula with no bleeding. Contrast-enhanced computed tomography revealed gas within the aneurysm sac and adhesion between the replaced aortic graft and intestinal tract, suggesting a graft infection. After 18 days of antibiotic treatment, he suddenly went into a state of shock, with massive fresh bloody stool and hematemesis, followed by cardiac arrest. An autopsy revealed communication between the artery and the ileum through an ulcerative fistula at the suture line between the left aortic graft branch and the left common iliac artery. Pathological analysis revealed tight adherence between the arterial and intestinal walls, but no marked sign of infection around the fistula, suggesting that the fistula had arisen due to physical stimuli.

CONCLUSIONS

Pathological analysis suggested that the present secondary aortoenteric fistula arose due to physical stimuli. This reaffirms the importance of keeping reconstructed aortas isolated from the intestine after abdominal aortic aneurysm surgery.

Comparing diagnostic accuracy of 18F-FDG-PET/CT, contrast enhanced CT and combined imaging in patients with suspected vascular graft infections

BACKGROUND

To evaluate the diagnostic accuracy of positron emission tomography/computed tomography with ¹⁸F-fluorodeoxyglucose (PET/CT), contrast-enhanced CT (CE-CT), and a combined imaging approach (CE-PET/CT) in patients with suspected vascular graft infection (VGI).

METHODS

PET/CT and CE-CT were performed prospectively in 23 patients with suspected VGI. Diagnostic accuracy for PET/CT was assessed by using previously suggested cut-off points for maximum standardized uptake values (SUV_max) measured in the vicinity of the graft. Using a new 4-point scale for visual grading, two readers independently assessed the diagnostic accuracy for CE-CT and combined CE-PET/CT. Microbiological culture, obtained after open biopsy or graft explantation, and clinical follow-up of the patients served as the standard of reference.

RESULTS

Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and accuracy of PET/CT for the diagnosis of VGI was 100%, 50%, 100%, 72.2%, and 78.3%, using the most favorable SUV_max cut-off ≥ 4.9. Respective values for CE-CT were 100%, 50%, 100%, 72.2%, and 78.3% for reader 1, and 92.3%, 80%, 88.9%, 85.7%, and 86.9% for reader 2; while respective values for combined CE-PET/CT were 100%, 70%, 100%, 81.3%, and 86.9% for reader 1, and 100%, 80%, 100%, 86.7%, and 91.3% for reader 2. Additionally, imaging provided a conclusive clinical diagnosis in patients without graft infection (i.e., other sites of infection): five of ten patients with CE-CT, six of ten patients with PET/CT, and seven of ten patients with combined CE-PET/CT.

CONCLUSION

The diagnostic accuracy of combined CE-PET/CT in patients with suspected VGI is very high. The combination of the high sensitivity of PET/CT in detecting metabolically active foci in infection, and the high specificity of CE-CT in detecting anatomic alterations, appears to be the reason why combined imaging outperforms stand-alone imaging in diagnosing VGI and may be supportive in future decision-making of difficult cases of suspected VGI. Clinical Trials.gov Identifier: NCT01821664.

Abdominal aortic aneurysms

An abdominal aortic aneurysm (AAA) is a localized dilatation of the infrarenal aorta. AAA is a multifactorial disease, and genetic and environmental factors play a part; smoking, male sex and a positive family history are the most important risk factors, and AAA is most common in men >65 years of age. AAA results from changes in the aortic wall structure, including thinning of the media and adventitia due to the loss of vascular smooth muscle cells and degradation of the extracellular matrix. If the mechanical stress of the blood pressure acting on the wall exceeds the wall strength, the AAA ruptures, causing life-threatening intra-abdominal haemorrhage - the mortality for patients with ruptured AAA is 65-85%. Although AAAs of any size can rupture, the risk of rupture increases with diameter. Intact AAAs are typically asymptomatic, and in settings where screening programmes with ultrasonography are not implemented, most cases are diagnosed incidentally. Modern functional imaging techniques (PET, CT and MRI) may help to assess rupture risk. Elective repair of AAA with open surgery or endovascular aortic repair (EVAR) should be considered to prevent AAA rupture, although the morbidity and mortality associated with both techniques remain non-negligible.

Construction of lncRNA-miRNA-mRNA networks reveals functional lncRNAs in abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) is one of the most significant causes of morbidity and mortality in populations aged >65 years worldwide. However, the underlying mechanisms of AAA based on the competitive endogenous RNA (ceRNA) hypothesis have remained elusive. In the present study, differently expressed long non-coding RNA (lncRNA)-microRNA (miRNA)-mRNA networks in AAA were constructed by analyzing public datasets, including GSE7084, GSE24194 from rats and that of a previous study. A total of 1,219 mRNAs, 2,093 lncRNAs and 57 miRNAs were identified to differently express in AAA. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed to explore the potential roles of differently expressed lncRNAs based on their regulating mRNAs. Based on the ceRNA hypothesis, lncRNA-miRNA-mRNA networks in AAA were, for the first time, constructed at a system-wide level. The present study identified 5 upregulated lncRNAs [nuclear paraspeckle assembly transcript 1, cyclin-dependent kinase inhibitor 2B antisense RNA 1, small Cajal body-specific RNA 10, AC005224.4 and SUMO1/sentrin/SMT3-specific peptidase 3-eukaryotic translation initiation factor 4A1] and the downregulated zinc ribbon domain containing 1 antisense RNA 1 as key lncRNAs in ceRNA networks. To the best of our knowledge, the present study was the first to screen ceRNA networks in AAA. In addition, key lncRNA-mRNA-biological processes analysis indicated that these key lncRNAs were involved in regulating signal transduction, protein amino acid phosphorylation, immune response, transcription, development and cell differentiation. The present study provides novel clues to explore the molecular mechanisms of AAA progression in terms of lncRNA implication.

The Society for Vascular Surgery practice guidelines on follow-up after vascular surgery arterial procedures

Although follow-up after open surgical and endovascular procedures is generally regarded as an important part of the care provided by vascular surgeons, there are no detailed or comprehensive guidelines that specify the optimal approaches with regard to testing methods, indications for reintervention, and follow-up intervals. To provide guidance to the vascular surgeon, the Clinical Practice Council of the Society for Vascular Surgery appointed an expert panel and a methodologist to review the current clinical evidence and to develop recommendations for follow-up after vascular surgery procedures. For those procedures for which high-quality evidence was not available, recommendations were based on observational studies, committee consensus, and indirect evidence. Recognizing that there are numerous published reports on the role of duplex ultrasound for surveillance of infrainguinal vein bypass grafts, the Society commissioned a systematic review and meta-analysis on this topic. The panel classified the strength of each recommendation and the corresponding quality of evidence on the basis of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system: recommendations were graded either strong or weak, and the quality of evidence was graded high, moderate, or low. The resulting recommendations represent a wide variety of open surgical and endovascular procedures involving the extracranial carotid artery, thoracic and abdominal aorta, mesenteric and renal arteries, and lower extremity arterial revascularization. The panel also identified many areas in which there was a lack of high-quality evidence to support their recommendations. This suggests that there are opportunities for further clinical research on testing methods, threshold criteria, and the role of surveillance as well as on the modes of failure and indications for reintervention after vascular surgery procedures.