Editor's Choice - European Society for Vascular Surgery (ESVS) 2020 Clinical Practice Guidelines on the Management of Vascular Graft and Endograft Infections

In-situ Bypass Is Associated with Superior Infection-free Survival Compared to Extra-Anatomic Bypass for the Management of Secondary Aortic Graft Infections Without Enteric Involvement

OBJECTIVE

The optimal revascularization modality following complete resection of aortic graft infection (AGI) without enteric involvement remains unclear. The purpose of this investigation is to determine the revascularization approach associated with the lowest morbidity and mortality using real-world data in patients undergoing complete excision of AGI.

METHODS

A retrospective, multi-institutional study of AGI from 2002-2014 was performed using a standardized database. Baseline demographics, comorbidities, and perioperative variables were recorded. The primary outcome was infection-free survival. Descriptive statistics, Kaplan-Meier survival analysis, and univariate and multivariable analyses were performed.

RESULTS

241 patients at 34 institutions from 7 countries presented with AGI during the study period (median age 68 years; 75% male). The initial aortic procedures that resulted in AGI were 172 surgical grafts (71%) and 66 endografts (27%) and 3 unknown (2%). 172 (71%) of the patients underwent complete excision of infected aortic graft material followed by in situ (in-line) bypass (ISB), including antibiotic-treated prosthetic graft (35%), autogenous femoral vein (NAIS) (24%), and cryopreserved allograft (41%). 69 patients (29%) underwent extra-anatomic bypass (EAB). Overall median Kaplan-Meier (KM) estimated survival was 5.8 years. Perioperative mortality was 16%. When stratified by ISB versus EAB, there was a significant difference in KM estimated infection-free survival (2910 days, IQR 391, 3771 versus 180 days, IQR 27, 3750 days; p<0.001). There were otherwise no significant differences in presentation, comorbidities, nor perioperative variables. Multivariable Cox regression showed lower infection-free survival among patients with EAB (HR 2.4, 95% CI 1.6-3.6; p<0.001), polymicrobial infection (HR 2.2, 95% CI 1.4-3.5; p=0.001), MRSA infection (HR 1.7, 95% CI 1.1-2.7; p=0.02), as well as the protective effect of omental/muscle flap coverage (HR 0.59, 95% CI 0.37-0.92; p=0.02).

CONCLUSIONS

After complete resection of AGI, perioperative mortality is 16% and median overall survival is 5.8 years. EAB is associated with nearly a two-and-half fold higher re-infection/mortality compared to ISB. Omental and/or muscle flap coverage of the repair appear protective.

Contemporary results with the biosynthetic glutaraldehyde denatured ovine collagen graft (Omniflow II) in lower extremity arterial revascularization in a septic context

OBJECTIVE

Prosthetic peripheral vascular graft infections are poorly evaluated, despite a grim prognosis with high mortality and major amputation rates. The vascular substitute of choice remains controversial when autologous veins are unavailable. The main objective of this study was to evaluate the mid-term results of a new alternative biosynthetic collagen graft (Omniflow II®) in an infected field in patients with unavailable or unsuitable autologous saphenous vein.

METHODS

This retrospective, observational, multicentric study included all consecutive patients in whom an Omniflow II® graft was used for infra-inguinal revascularization in the context of sepsis from January 2015 to January 2020. The primary endpoint was freedom from major amputation; secondary endpoints were 30-day mortality, perioperative morbidity, and estimated survival, patency, and freedom from reinfection estimated using the Kaplan-Meier method.

RESULTS

Twenty-nine patients (27 men, median age 69 years (IQR:60;76) were included. Fever was present in 58.6% of cases, a septic rupture in 17.9%, and a pseudo-aneurysm in 25.0%. The 30-day mortality rate was 3.4% (septic shock). The median follow-up reached 49 months. At 1 and 3 years, the estimated freedom from major amputation was 88.4% and 83.9%, survival was 96%, primary patency was 74.6% and 65.8%, secondary patency was 82.1% and 77.7% and reinfection free-survival was 85.6%. There were 7 occlusions (1 iliofemoral, 1 below-knee, and 5 above-knee bypasses), 3 explantations for persistent sepsis, 4 reinfections (all within the first 6 months which led to 1 death and 3 major amputations), and a total of 4 major amputations. The risk of major amputation increased with bypass reinfection (p=.004), occlusion (p=.005), and polymicrobial infection (p=.05).

CONCLUSION

In a septic context, the Omniflow II® bioprosthetic graft represents an acceptable vascular substitute in the absence of an autologous vein. It provides acceptable freedom from major amputation and reinfection considering the seriousness of this pathology. This usage remains outside the instructions for use, it is, therefore, essential to pursue longer-term studies in larger cohorts.

Evidence-based guideline of the European Association of Nuclear Medicine (EANM) on imaging infection in vascular grafts

Purpose

Consensus on optimal imaging procedure for vascular graft/endograft infection (VGEI) is still lacking and the choice of a diagnostic test is often based on the experience of single centres. This document provides evidence-based recommendations aiming at defining which imaging modality may be preferred in different clinical settings and post-surgical time window.

Methods

This working group includes 6 nuclear medicine physicians appointed by the European Association of Nuclear Medicine, 4 vascular surgeons, and 2 radiologists. Vascular surgeons formulated 5 clinical questions that were converted into 10 statements and addressed through a systematic analysis of available literature by using PICOs (Population/problem–Intervention/Indicator–Comparator–Outcome) strategy. Each consensus statement was scored for level of evidence and for recommendation grade, according to the Oxford Centre for Evidence-based Medicine criteria.

Results

Sixty-six articles, published from January 2000 up to December 2021, were analysed and used for evidence-based recommendations.

Conclusion

Computed tomography angiography (CTA) is the first-line imaging modality in suspected VGEI but nuclear medicine modalities are often needed to confirm or exclude the infection. Positron emission tomography/computed tomography (PET/CT) with 2-deoxy-2-[¹⁸F]fluoro-D-glucose ([¹⁸F]FDG) has very high negative predictive value but it should be performed preferably at least 4 months after surgery to avoid false positive results. Radiolabelled white blood cell (WBC) scintigraphy, given its high diagnostic accuracy, can be performed at any time after surgery.

Preamble

The European Association of Nuclear Medicine (EANM) is a professional no-profit medical association that facilitates communication worldwide between individuals pursuing clinical and research excellence in nuclear medicine. The EANM was founded in 1985. EANM members are physicians, technologists, and scientists specializing in the research and practice of nuclear medicine. The EANM will periodically define new guidelines for nuclear medicine practice to help advance the science of nuclear medicine and to improve the quality of service to patients throughout the world. Existing practice guidelines will be reviewed for revision or renewal, as appropriate, on their fifth anniversary or sooner, if indicated. Each practice guideline, representing a policy statement by the EANM, has undergone a thorough consensus process in which it has been subjected to extensive review. The EANM recognizes that the safe and effective use of diagnostic nuclear medicine imaging requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the published practice guideline by those entities not providing these services is not authorized. These guidelines are an educational tool designed to assist practitioners in providing appropriate care for patients. They are not inflexible rules or requirements of practice and are not intended, nor should they be used, to establish a legal standard of care. For these reasons and those set forth below, the EANM suggests caution against the use of the current consensus document in litigation in which the clinical decisions of a practitioner are called into question. The ultimate judgement regarding the propriety of any specific procedure or course of action must be made by the physician or medical physicist in the light of all the circumstances presented. Thus, there is no implication that an approach differing from the consensus document, standing alone, is below the standard of care. To the contrary, a conscientious practitioner may responsibly adopt a course of action different from that set forth in the consensus document when, in the reasonable judgement of the practitioner, such course of action is indicated by the condition of the patient, limitations of available resources, or advances in knowledge or technology subsequent to publication of the consensus document. The practice of medicine includes both the art and the science of the prevention, diagnosis, alleviation, and treatment of disease. The variety and complexity of human conditions make it impossible to always reach the most appropriate diagnosis or to predict with certainty a particular response to treatment. Therefore, it should be recognized that adherence to this consensus document will not ensure an accurate diagnosis or a successful outcome. All that should be expected is that the practitioner will follow a reasonable course of action based on current knowledge, available resources, and the needs of the patient, to deliver effective and safe medical care. The sole purpose of this consensus document is to assist practitioners in achieving this objective.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00259-022-05769-x.

Mycotic arterial aneurysm secondary to BCG intravesical instillation: A review

OBJECTIVE

Mycotic aortic aneurysm is a rare and life-threatening pathology. The first case of mycotic aneurysm induced by immunotherapy with bacille Calmette-Guérin for malignancy was published in 1988. The main objective of this review is to characterize this rare pathology.

MATERIALS AND METHODS

Since then, 60 cases of arterial aneurysm following intra vesical BCG instillation have been described in the literature. All cases have been included, and characteristics have been collected retrospectively, with simple statistical analyses of the cases.

RESULTS

We present a brief review from 1988 to 2022 enhancing the contemporary understanding of this arterial infection. Mycotic aneurysm secondary to BCG instillation has a poor prognosis, up to 50% complication and 15% mortality at 1 month, whether managed by open repair or endovascular means.

CONCLUSION

BCG mycotic aneurysm is an extremely serious condition, the diagnosis of which must be considered at an early stage in order to adapt diagnostic and therapeutic strategies.

Neoaortoiliac system in treating aortic graft infections: a single center long-term experience and review of the literature

BACKGROUND

Aortic graft infection represents one of the most challenging and life-threatening complication of surgical and endovascular treatment of aortic pathologies. The aim of this study was to report the results of a single center with in-situ revascularization for the treatment of aortic graft infections using the neo-aorto-iliac system (NAIS) and to review the literature about this surgical technique.

METHODS

We retrospectively reviewed our aortic graft infection case series and in-situ revascularization using the neo-aorto-iliac system. The study was conducted from January 2009 to June 2020. The primary outcomes analyzed were early mortality (<30 days), late mortality (>30 days), reinfection rate. Secondary outcomes were the primary patency rate, the secondary patency rate, and the lower limb salvage rate. A literature review of the last twenty years was performed on international medical databases Pubmed (Medline), Scopus and Web of Science.

RESULTS

During study period, 12 patients, all male (median age of 69 years [range: 52-87 years]), underwent to infected graft explantation and revascularization by NAIS using femoral-popliteal veins. Six cases were complicated by aorto-enteric fistulas, five were duodenal and one was colon. Patients spent the immediate postoperative period in the Intensive Care Unit for a median time of 4 days (range: 0-9 days). The median length of hospital stay was 27.5 days (range: 1-66 days). The mean follow-up was 21.5 months (range: 0-120). The 30-day mortality rate was 25% (3 patients) due to postoperative complications. No patient dropped out of the follow-up protocol. The primary patency rate was 92% while the secondary patency rate was 100%. No patient underwent lower limb amputation. Persistence of infection occurred in 1 case (8.3%). Overall Kaplan-Meier survival estimates were 75% for 30 days, 50% for 1 year, 48% for 5 years. Literature analysis identified 19 case series.

CONCLUSIONS

The literature regarding NAIS has low statistical evidence due to retrospective design of the studies. Our results are in agreement with retrospective studies in the literature. When the surgical team is confident with NAIS, this technique should be considered the preferred method, considering an acceptable and comparable mortality rate with other techniques and a better rate of patency, resistance to graft degeneration, recurrent infections and amputation rate.

Treatment of vascular graft infections: gentamicin-coated ePTFE grafts reveals strong antibacterial properties in vitro

Vascular graft infections (VGI) are severe complications in prosthetic vascular surgery with an incidence ranging from 1 to 6%. In these cases, synthetic grafts are commonly used in combination with antimicrobial agents. Expanded polytetrafluoroethylene (ePTFE) is in clinical use as a synthetic graft material and shows promising results by influencing bacterial adhesion. However, the literature on antibiotic-bound ePTFE grafts is scarce. Gentamicin is a frequently used antibiotic for local treatment of surgical site infections, but has not been evaluated as antimicrobial agent on ePTFE grafts. In this study, we examine the antimicrobial efficacy and biocompatibility of novel types of gentamicin-coated ePTFE grafts in vitro. ePTFE grafts coated with gentamicin salt formulations with covalently-bound palmitate were evaluated in two drug concentrations (GP1.75% and GP3.5%). To investigate effects from types of formulations, also suspensions of gentamicin in palmitate as well as polylactide were used at comparable levels (GS + PA and GS + R203). Antibacterial efficacies were estimated by employing a zone of inhibition, growth inhibition and bacterial adhesion assay against Staphylococcus aureus (SA). Cytotoxicity was determined with murine fibroblasts according to the ISO standard 10993-5. Gentamicin-coated ePTFE grafts show low bacterial adherence and strong antibacterial properties in vitro against SA. Bactericidal inhibition lasted until day 11. Highest biocompatibility was achieved using gentamicin palmitate GP1.75% coated ePTFE grafts. ePTFE grafts with gentamicin-coating are effective in vitro against SA growth and adherence. Most promising results regarding antimicrobial properties and biocompatibility were shown with chemically bounded gentamicin palmitate GP1.75% coatings. Graphical abstract.

A Narrative Review of Experimental Models to Study Vascular Grafts Infections

Background

Many experimental models have been developed to decipher the mechanisms of vascular graft and endograft infections (VGEIs), and to elaborate strategies to prevent or treat their occurrence. A systematic literature research was conducted to identify the most accurate models for studying VGEIs, depending on the research question.

Methods

A narrative literature search was conducted using the MEDLINE and Cochrane databases, with no set limit on the date of publication, up to 10 August 2021. Ex vivo, in vitro, and in vivo animal studies on VGEIs, published in English or French, were selected. Cross references retrieved from selected articles on PubMed database were also included. Data on microorganisms and grafts studied, details of experimental models, and of graft implantation and removal in animal studies were collected.

Results

A total of 243 studies were included in the review after reading the full length articles: 55 in vitro studies, 169 animal studies, 17 studies which used both in vitro and animal models, and two ex vivo studies. Many differences in model characteristics were seen. The main in vitro model was the incubation of a graft sample in a bacterial solution, used to study the first steps of infection. In animals, vascular large animal models (dogs and pigs) were the most commonly described but supplanted over time by extravascular and particularly subcutaneous mouse and rat models, which have been reported increasingly over the last few years. In animal models, antibiotic prophylaxis and therapy were rarely administered (27.4% and 19.9%, respectively), and vascular reconstruction after VGEIs even less frequently (9.8%).

Conclusion

Despite protocol discrepancies, it was possible to dinstinguish three main experimental models (i.e., in vitro and in vivo vascular models, and extravascular models), which all remain of interest to study specific phases of VGEIs.

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Experimental models of vascular (endo)graft infections (VGEIs) can be split into in vitro, extravascular, and vascular ones.

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Each of these three groups can help answer specific questions on VGEIs.

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To improve reproducibility, future experimental studies require standardisation.

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Experimental studies should reproduce real life conditions as accurately as possible.

Listeria monocytogenes endograft infection after fenestrated endovascular aneurysm repair—a case report

An extremely uncommon cause of endograft infections, Listeria monocytogenes graft infections are associated with high morbidity and mortality. Best managed with complete graft resection and long-term antibiotic therapy, we present a rare case of L. monocytogenes aortic graft infection managed successfully with direct sac drainage and lifelong suppressive antibiotic therapy.

Percutaneous Drainage for Aortic Graft Infection Post-aneurysm Repair: A Viable Option?

Purpose

Non-operative management of aortic graft infection is usually only considered in a palliative context. We describe the safety, efficacy, and clinical outcomes of percutaneous drainage of aortic graft infections (AGI) following either open or endovascular repair of aneurysmal disease.

Methods

Twelve consecutive patients (11 males, 1 female, mean age 72.7 ± 10.3 years, age range 52-88 years) between January 2010-July 2020 who underwent percutaneous drain insertion in either an infected aortic sac or periaortic abscess cavity following endovascular or open surgical graft repair were identified. Patient and procedural characteristics as well as clinical outcomes were determined.

Results

Of the 12 patients who underwent percutaneous drain insertion, five (41.7%) had undergone open abdominal aneurysm repair, one (8.3%) open thoracoabdominal aneurysmal repair, and six (50%) endovascular abdominal aneurysm repairs. Drain size ranged from 10-20 French. All were inserted under ultrasound (US), computed tomography (CT), and/or fluoroscopic guidance. Median duration of drain placement was 55.2 days (range 3-174). Five patients (41.7%) had the drain in place as a stabilizing bridge until or after definitive surgical explantation and aortic reconstruction. Seven patients (58.3%) were managed with drain placement and antibiotic therapy without surgical intervention. Six (50%) were alive at the most recent time of follow-up (median, 732 days, range 166-1650 days). Three patients (25%) died during follow-up with causes including erosion of aortic reconstruction into sigmoid colon, unrelated chronic obstructive pulmonary disease exacerbation, and severe clostridium difficile colitis and pseudomonal pneumonia (median 1244 days, range 992-1597 days). Three (25%) patients were lost to follow-up. No drain-related complications were noted.

Conclusion

Percutaneous drainage of AGI following endovascular or open aneurysm repair is a safe and viable management option either as a temporizing measure as a bridge to surgical graft explantation or as a non-surgical therapy for long term management.

Treatment of an Infected TEVAR with Extra- and Endovascular Bacteriophage Application

Introduction

Graft infections are severe complications. Surgical resection of infected aortic stent grafts is associated with high mortality and morbidity. Therefore, alternatives or adjuncts to antibiotic treatment and extensive surgery are urgently needed.

Report

A 67 year old woman was admitted with a methicillin sensitive Staphylococcus aureus infected stent graft in the thoracic aorta. Local infection was confirmed by PET-CT imaging. Surgical resection of the stent graft was not feasible because of comorbidities. Therefore, a three step approach for local bacteriophage treatment was performed as a last resort treatment. Firstly, the para-aortic tissue was debrided via left thoracotomy, a bacteriophage suspension was applied on the outer surface of the aorta, and a vacuum irrigation system was installed. After repeated alternating instillation of the bacteriophage suspension for three days, as a second step, the vacuum sponges were removed and a bacteriophage containing gel was applied locally on the outer surface of the aorta. In the third step, the bacteriophage containing gel was applied to a thoracic stent graft, which in turn was placed endovascularly into the infected stent.

Discussion

After 28 days, the patient was discharged from hospital with normalised infection parameters. PET-CT imaging at three and 12 months post-intervention did not show signs of infection in or around the thoracic aorta. This Case demonstrates successful treatment of an infected endovascular stent graft by application of bacteriophages both to extravascular and, as a novel approach, endovascular sites using a bacteriophage coated stent graft.

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Vascular graft infections are severe complications in vascular surgery.

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Bacteriophages are viruses that have lytic activity against specific bacteria.

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An infected stent graft in the thoracic aorta was treated with bacteriophages.

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Bacteriophages were applied both endo- and extravascularly.

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Local bacteriophage application was combined with systemic antibiotic treatment.

Long-term prognosis following vascular graft infection: a 10-year cohort study

Background

Vascular graft infection (VGI) remains a severe disease with high mortality and relapse rates. We performed a retrospective single-center cohort study to highlight factors associated with long-term all-cause mortality in patients with vascular graft infection.

Methods

All patients hospitalized in our facility over 10 years for VGI were included. VGI was defined by the presence of a vascular graft or an aortic stent graft (stent or fabric), associated with 2 criteria among clinical, biological, imaging, or microbiological elements in favor of VGI. The primary outcome was all-cause mortality. Empirical antibiotic therapy was considered as appropriate when all involved pathogens were susceptible in vitro to the antibiotics used. The surgical strategy was defined as nonoptimal when the graft was not removed in a late-onset surgery (>3 months) or no surgery was performed.

Results

One hundred forty-six patients were included. Empirical antibiotic therapy was administered in 98 (67%) patients and considered appropriate in 55 (56%) patients. Surgery was performed in 136 patients (96%) and considered as optimal in 106 (73%) patients. In multivariable analysis, appropriate empirical antibiotic therapy was associated with a lower probability of mortality (hazard ratio, 0.47 [95% confidence interval, .30–.79]; P = .002). Long-term survival did not differ according to whether the surgical strategy was considered optimal or not (log-rank = 0.66).

Conclusions

Appropriate empirical antibiotic therapy is a cornerstone of the management of VGI. Whenever possible, antibiotics must be associated with optimal surgical management. However, surgery could potentially be avoided in comorbid patients who are treated with appropriate antibiotics.

Aortic graft explants - A single institution analysis of incidence and outcomes

OBJECTIVES

Explantation of both endovascular endovascular aneurysm repair and open aortic grafts is a procedure associated with high peri-operative risk, and the current study sought to determine the outcomes and trends over time in these patients.

METHODS

This study examined data from all patients undergoing explant of an aortic graft (both open and endovascular) between January 2004 and December 2020 at a single centre. Variables analysed included comorbidities, duration to and indication for explantation, type of revascularization, in-hospital complications and mortality, duration of hospital and ICU stay, and out-patient mortality.

RESULTS

Of 688 open and 1352 EVARs performed, 46 patients underwent 48 explants. Five were open grafts and 43 were endografts, equating to an explant rate of 0.73% of open and 3.18% EVARs. Average time to explant was 70 months, with patients presenting electively having a significantly longer duration to representation than those presenting emergently (51 vs 44 months, p=0.003). Indication for explant was endoleak in 70%, infection in 23%, and occlusion in 6%. Of the endoleaks, 61% of were Type 1, 22% Type II, 11% Type IV, and 6% Type V. On representation, 17 patients (35%) were symptomatic. Overall mortality rate was 8.3%, with a trend for higher mortality in emergent than elective presentations (11.8 vs 6.5%, p=0.55). There was no change in explant rate over time.

CONCLUSIONS

Elective aortic graft explantation is associated with low mortality, despite its complexity and patient comorbidities. Patients presenting with symptoms suffered higher mortality and a longer post-operative course, suggesting that aortic graft explantation should be considered sooner rather than later, rather than persisting with repeated endovascular management.

Acute Phase Pilot Evaluation of Small Diameter Long iBTA-Induced Vascular Graft “Biotube” in a Goat Model

Objective

There is a need for small diameter vascular substitutes in the absence of available autologous material. A small diameter, long tissue engineered vascular graft was developed using a completely autologous approach called “in body tissue architecture technology (iBTA)”. The aim of this pilot study was to evaluate “Biotubes”, iBTA induced autologous collagenous tubes, for their potential use as small diameter vascular bypass conduits.

Methods

Biotubes (internal diameter 4 mm, length 50 cm, wall thickness 0.85 mm) were prepared by subcutaneous embedding of plastic moulds (Biotube Maker) in three goats for approximately two months. Allogenic Biotubes (length 10 cm [n = 2], 15 cm [n = 2], 22 cm [n = 2]) were bypassed to both carotid arteries by end to side anastomosis with their ligation between the anastomoses in another three goats. Residual Biotubes were examined for their mechanical properties. After four weeks, the harvested Biotubes were evaluated histologically.

Results

All Biotubes had sufficient pressure resistance, approximately 3000 mmHg. Although wall thickening occurred at two proximal anastomosis sites, all six grafts were patent without luminal thrombus formation, stenosis, or aneurysm deformation throughout the implantation period. Endothelial cells covered both anastomosis sites almost completely, with partial covering in the central portion of the grafts. Furthermore, α smooth muscle actin positive cells infiltrated the middle layer along almost the entire graft length.

Conclusion

This preliminary study showed that small diameter, long, tissue engineered Biotubes could function properly as arterial bypass conduits in a large animal for one month without any abnormal change in vascular shape. Thus, small diameter, long Biotubes are potentially viable conduits, which are biocompatible and labour non-intensive, and therefore, suitable for clinical practice. Additionally, Biotubes can start the regeneration process in a short period of time.

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Small diameter, in body tissue architecture induced tissue engineered vascular graft.

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Potential for patients with critical limb ischaemia without useable autologous vein.

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Biocompatible and labour non-intensive tissue engineered vascular graft.

Pre-clinical In Vitro Models of Vascular Graft Coating in the Prevention of Vascular Graft Infection: A Systematic Review

OBJECTIVE

Vascular graft infection (VGI) is a feared complication. Prevention is of the utmost importance and vascular graft coatings (VGCs) could offer a potential to do this, with in vitro research a first crucial step. The aim of this study was to summarise key features of in vitro models investigating coating strategies to prevent VGI in order to provide guidance for the setup of future translational research.

DATA SOURCES

A comprehensive search was performed in MEDLINE, Embase, and Web of Science.

METHODS

A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. For each database, a specific search strategy was developed. Quality was assessed with the Toxicological data Reliability Assessment Tool (ToxRTool). In vitro models using a VGC and inoculation of the graft with a pathogen were included. The type of graft, coating, and pathogen were summarised. The outcome assessment in each study was evaluated.

RESULTS

In total, 4 667 studies were identified, of which 45 papers met the inclusion criteria. The majority used polyester grafts (68.2%). Thirty-one studies (68.9%) included antibiotics, and nine studies (20%) used a commercial silver graft in their protocol. New antibacterial strategies (e.g., proteolytic enzymes) were investigated. A variety of testing methods was found and focused mainly on bacterial adherence, coating adherence and dilution, biofilm formation, and cytotoxicity. Ninety-three per cent of the studies (n = 41) were considered unreliable.

CONCLUSION

Polyester is the preferred type of graft to coat on. The majority of coating studies are based on antibiotics; however, new coating strategies (e.g., antibiofilm coating) are coming. Many in vitro setups are available. In vitro studies have great potential, they can limit the use, but cannot replace in vivo studies completely. This paper can be used as a guidance document for future in vitro research.

Case Report: A Pseudoaneurysm Involving the Left Common Iliac Artery Secondary to Brucellosis: A Rare Case Report

Pseudoaneurysms of the common iliac artery caused by Brucellosis are exceedingly uncommon. Infected common iliac artery pseudoaneurysms, particularly those caused by brucellosis, are more difficult to diagnose and cure than general pseudoaneurysms. The risk of mortality is significantly high in this condition. Nonsurgical treatment of a brucellosis-induced common iliac artery pseudoaneurysm is futile, and it should be operated on as soon as feasible. Long-term and multi-course antibacterial therapy with combination antibiotics is required. For the treatment of Brucella-infected pseudoaneurysms, endovascular surgery can be both effective and safe.

In situ Reconstruction with Autologous Veins for the Treatment of Infected Abdominal Endografts: Single Center Experience

Background: Vascular graft infection is a feared complication with high mortality and morbidity rates. Complete excision with in situ repair is recommended. We report our experience with patients suffering of abdominal aortic endograft infection undergoing excision and in situ reconstruction with autologous vein. Patients and Methods: All patients who underwent excision of an abdominal aortic endograft and in situ reconstruction with autologous superficial femoral veins between April 2005 and June 2021 were retrospectively reviewed. Primary outcome measures were mortality and reinfection. Secondary outcome measure was patient morbidity. Results: Fifteen patients (14 male; 93%) were included. Twenty percent of the index procedures (N = 3) were performed at our hospital, 80% (N = 12) were referred patients. Three aorto-enteric fistulae were seen. Staphylococci and enterococci were the most common pathogens (N = 8; 53%). In two out of six patients (33%) with an endograft with suprarenal fixation, the suprarenal fixation stent was left in situ. 30-day mortality rate was 6.6% (N = 1). Median follow-up time was 12 months (range 0-85). During follow-up, no reinfection was seen. Serious morbidity was witnessed in 2 patients (sepsis due to bowel leakage (N = 1), pneumonia (N = 2), hemodialysis (N = 1)). Eventration was the most common late morbidity observed (N = 5). Conclusions: Surgical treatment of vascular abdominal endograft infection by in situ reconstruction with autologous deep vein is a challenging procedure. If a multidisciplinary approach is applied and patients are centralized in experienced centers, acceptable mortality and morbidity rates can be achieved.

Stapled Porcine Pericardium Displays Lower Infectivity In Vitro Than Native and Sutured Porcine Pericardium

BACKGROUND

Biological xenografts using tubulized porcine pericardium are an alternative to replace infected prosthetic graft. We recently reported an innovative technique using a stapled porcine pericardial bioconduit for immediate vascular reconstruction in emergency. The objective of this study is to compare the growth and adherence to grafts of bacteria and yeast incubated with stapled porcine pericardium, sutured or naked pericardium.

MATERIAL AND METHODS

One square centimeter of porcine pericardial patches, with or without staples or sutures, was incubated with 10⁵ colony forming units of Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, and Candida albicans for 1, 6, and 24 h. The medium was collected to quantify planktonic microorganisms, while grafts were sonicated to quantify adherent microorganisms. Dacron and Dacron Silver were analyzed in parallel as synthetic reference prostheses.

RESULTS

Stapled porcine pericardium reduced the growth and the adherence of E coli (2- to 30-fold; P < 0.0005), S aureus (11- to 1000-fold; P < 0.0006), S epidermidis (>500-fold; P < 0.0001), and C albicans (12- to 50-fold; P < 0.0001) when compared to medium alone (growth) and pericardium or Dacron (adherence). Native and sutured porcine pericardium interfered with the growth and the adherence of E coli and C albicans, and Dacron with that of S epidermidis. As expected, Dacron Silver was robustly bactericidal.

CONCLUSIONS

Stapled porcine pericardium exhibited a lower susceptibility to infection by bacteria and yeasts in vitro when compared to the native and sutured porcine pericardium. Stapled porcine pericardium might be a good option for rapid vascular grafting without increasing infectivity.

OUTCOME IN PATIENTS AFTER AUTOLOGOUS FEMORAL VEIN RECONSTRUCTION FOR PRIMARY AORTIC INFECTION AND AORTIC GRAFT INFECTION: A CASE SERIES

OBJECTIVES

For surgical treatment of primary aortic infection and aortic graft infection, in situ reconstruction with autologous vein(s) has the lowest rates of re-infection and of graft thrombosis. In this study, we have assessed the outcome after autologous femoral vein reconstruction in patients with aortic (graft) infection and we provide insights into the specific technical surgical considerations of the procedure.

METHODS

In this retrospective single-center study, all patients who underwent autologous femoral vein reconstruction because of primary aortic infection or aortic graft infection between January 2012 and January 2020 were included. The primary outcome parameter was 30-day mortality.

RESULTS

Twenty-nine patients with autologous femoral vein reconstruction for a primary aortic infection (n = 3) or aortic graft infection (n = 26) were included. An aorto-enteral fistula was detected in 13 patients (49%). Venous reconstruction of the aorta was performed with a single femoral vein in 17 patients (59%), and two femoral veins in 12 patients (41%). Thirty-day mortality was 17%. Relapse of infection occurred in two patients (7%) and no amputations were needed. One year after surgery, only three patients (10%) still needed stockings and after two years none of the patients used stockings.

CONCLUSIONS

Central aortic reconstruction with femoral veins is a durable solution for primary aortic and aortoiliac graft infections with a low incidence of reinfections, amputations, and venous hypertension.

Comparison of Clinical Outcomes between Salvage and Elective Thoracic Endovascular Aortic Repair in Patients with Advanced Esophageal Cancer with Aortic Invasion: A Retrospective Cohort Study

Aortoesophageal fistula (AEF) caused by esophageal cancer (EC) is a rare but life-threatening complication. However, the optimal management strategy remains undetermined. Previous cases have demonstrated that thoracic endovascular aortic repair (TEVAR) is effective for prophylactic management. In our study, we evaluated the management of AEF with elective TEVAR over salvage TEVAR. In our single-center retrospective cohort study, forty-seven patients with cT4M0 EC were included in this study, and we divided them into salvage (Group S) and elective (Group E) groups based on whether TEVAR was performed before the hemorrhagic AEF occurred. Our study outcomes included survival and complication rate after TEVAR. Group E showed better overall 90-day survival and aortic-event-free survival in 90-day and 180-day over Group S. More patients in Group E could receive subsequent chemoradiotherapy or esophagectomy. Significantly fewer AEF-related complications, including recurrent hemorrhagic events after TEVAR, hypoperfusion-related organ injury, and bloodstream infection, were noted in Group E. In patients with advanced EC-invading aorta, elective TEVAR offered an early overall and aortic-event-free survival benefit compared to salvage TEVAR. By reducing the AEF-related complications, elective TEVAR could provide more patients receiving subsequent curative-intent treatment.

Vascular Graft Infections With Candida: A Factor for Increased Mortality in in-situ Reconstructions

BACKGROUND

The empiric antibiotic regimen started after deep cultures and explantation of the graft mostly do not cover antifungals. We retrospectively studied the outcome of candida compared to non-candida VGI and assessed whether these results could justify the addition of antifungals to the empiric antibiotics in the early postoperative period.

METHODS

All patients treated for infected aorto(ilio)femoral graft with excision and reconstruction at the vascular department of University Hospitals Leuven between January 2010 and 2017 (n = 56) were studied retrospectively. Patients were allocated to the candida group (n = 10) or non-candida group (n = 46) according to the presence of Candida in deep culture isolates.

RESULTS

All-cause mortality was significantly higher in the candida group compared to the non-candida group. All-cause 30-day mortality was 40% and 13% for both groups respectively (P = 0.066). At 5 years this was 90% and 46% respectively (P = 0.014). In the candida group 6 patients (60%) had to be revised in the operating room due to bleeding, compared to 5 patients (11%) in the non-candida group (P = 0.002).  Two patients (20%) and 5 patients (11%) had to be readmitted to the ICU, respectively.

CONCLUSION

Survival of candida related VGI is significantly worse, especially in the first 5 postoperative months. This could justify the addition of an antifungal to the early empiric postoperative antibiotic cocktail, especially in patients with an aorto-enteric fistula. A cost-benefit analysis could be useful to evaluate the yield.

Comparison of the bifurcated graft reconstruction and aortic stump closure in open surgical conversion after endovascular aneurysm repair

OBJECTIVES

The optimal management of the aortic stump in open surgical conversion (OSC) after AAA endovascular aneurysm repair (EVAR) is debated. Therefore, we aimed to compare the efficacies and safety between the bifurcated prosthetic vascular graft in situ stump reconstruction (p-graft ISSR) and aortic stump closure (ASC) in OSC.

METHODS

We analyzed 973 elective AAA patients admitted from 1/1/2001 to 12/31/2020, at the First Affiliated Hospital of Sun Yat-sen University. We conducted a statistical analysis of the clinical characteristics, procedural data, as well as outcomes and technique considerations of aortic stump management in OSC patients.

RESULTS

A total of 24 male patients had OSC after EVAR. The rate of stent graft infection was 54.17% before OSC. Eleven patients underwent ASC, and 13 patients were treated with p-graft ISSR. The major complication after OSC was aortic stump bleeding (total incidence was 37.50%) (1 patient with a periaortic hematoma and 8 patients with a stump blowout). The total incidences of stump blowout between the patients with ASC and those with p-graft ISSR were significantly different (45.45% vs. 23.08%, p<0.05). The total perioperative mortality was 25.00% (6 patients with stump blowouts). The perioperative survival rates between these two aortic stump management approaches were 72.72% and 76.92% (ASC vs. p-graft ISSR, p<0.05). In total, 18 patients were followed up (3-180 months). There were 3 aorta-related deaths during the late follow-up period (including both of the 2 stump-blowout-related deaths just treated with ASC).

CONCLUSIONS

If the condition of the aorta and peri-aortic tissue are suitable for a prosthetic graft bypass, the p-graft ISSR is highly recommended for OSC patients after EVAR.

Superior vena cava graft infection in thoracic surgery: a retrospective study of the French EPITHOR database

 

OBJECTIVES

To report our experience on the management of superior vena cava graft infection.

METHODS

Between 2001 and 2018, patients with superior vena cava synthetic graft or patch reconstruction after resection of intrathoracic tumours or benign disease were selected retrospectively from the French EPITHOR database and participating thoracic centres. Our study population includes patients with superior vena cava graft infection, defined according to the MAGIC consensus. Superior vena cava synthetic grafts in an empyema or mediastinitis were considered as infected.

RESULTS

Of 111 eligible patients, superior vena cava graft infection occurred in 12 (11.9%) patients with a polytetrafluoroethylene graft secondary to contiguous contamination. Management consisted of either conservative treatment with chest tube drainage and antibiotics (n = 3) or a surgical graft-sparing strategy (n = 9). Recurrence of infection appears in 6 patients. Graft removal was performed in 2 patients among the 5 reoperated patients. The operative mortality rate was 25%.

CONCLUSIONS

Superior vena cava graft infection may develop as a surgical site infection secondary to early mediastinitis or empyema. Graft removal is not always mandatory but should be considered in late or recurrent graft infection or in infections caused by aggressive microorganisms (virulent or multidrug resistant bacteria or fungi).

Epithelioid Angiosarcoma after EVAR. A Case Report

INTRODUCTION

Endovascular aneurysm repair (EVAR) has become a standard in the treatment of aneurysms. However, complications still occur. Endoleaks are the most common. Graft infection diagnosis might be challenging. Even uncommon, we describe a case of epithelioid angiosarcoma after EVAR.

CASE REPORT

A 64-year-old male came to our emergency department with left lumbar and left thigh flexion pain, increasing since a month. Four years before, he had been treated for a left common iliac artery aneurysm extending to the aortic bifurcation by EVAR with a bifurcated unibody aortic (AFX Endologix) endograft. The year before the admission, he was treated twice by percutaneous angioplasty for a symptomatic mural thrombus of the left endograft limb. On admission, CT angiogram showed a recurrence of the aneurysm associated with elevated lab inflammatory markers. FDG-PET-CT showed an abnormal tracer uptake in the endograft limbs and in the left inguinal area. White blood cell scintigraphy did not show any sign of endograft infection. CT angiogram performed 2 months later showed an additional increase of the infrarenal aortic and left common iliac aneurysms. We removed the endograft. Histological analysis showed an epithelioid angiosarcoma. Patient died a few weeks later during chemotherapy.

CONCLUSION

For patients that have undergone EVAR and have subsequently developed morphological changes of the aortic wall and aneurysmal sac, an aortic tumor should be considered. Imaging diagnosis was challenging for this rare case of epithelioid angiosarcoma.

Editor's Choice - Outcome of Radical Surgical Treatment of Abdominal Aortic Graft and Endograft Infections Comparing Extra-anatomic Bypass with In Situ Reconstruction: A Nationwide Multicentre Study

OBJECTIVE

Abdominal aortic graft and endograft infection (AGI) is primarily treated by resection of the infected graft and restoration of distal perfusion through extra-anatomic bypass (EAB) or in situ reconstruction/repair (ISR). The aim of this study was to compare these surgical strategies in a nationwide multicentre retrospective cohort study.

METHODS

The Swedish Vascular Registry (Swedvasc) was used to identify surgically treated abdominal AGIs in Sweden between January 1995 and May 2017. The primary aim was to compare short and long term survival, as well as complications for EAB and ISR.

RESULTS

Some 126 radically surgically treated AGI patients were identified - 102 graft infections and 24 endograft infections - treated by EAB: 71 and ISR: 55 (23 neo-aorto-iliac systems, NAISs). No differences in early 30 day (EAB 81.7% vs. ISR 76.4%, p = .46), or long term five year survival (48.2% vs. 49.9%, p = .87) were identified. There was no survival difference comparing NAIS to other ISR strategies. The frequency of recurrent graft infection during follow up was similar: EAB 20.3% vs. ISR 17.0% (p = .56). Survival and re-infection rates of the new conduit did not differ between NAIS and other ISR strategies. Age ≥ 75 years (odds ratio [OR] 4.0, confidence interval [CI] 1.1 - 14.8), coronary artery disease (OR 4.2, CI 1.2 - 15.1) and post-operative circulatory complications (OR 5.2, CI 1.2 - 22.5) were associated with early death. Prolonged antimicrobial therapy (> 3 months) was associated with reduced long term mortality (HR 0.3, CI 0.1 - 0.9).

CONCLUSION

In this nationwide multicentre study comparing outcomes of radically treated AGI, no differences in survival or re-infection rate could be identified comparing EAB and ISR.

Clinical Studies Reporting on Vascular Graft Coatings for the Prevention of Aortic Graft Infection: A Systematic Review and Meta-Analysis

OBJECTIVE

The aim of this study was to investigate the efficacy of vascular graft coatings used in the aortic position to prevent vascular graft infection (VGI).

METHODS

A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines using a pre-registered protocol (CRD42020206436). Eligible studies used a vascular graft coating in the aortic position and reported on VGI. A search was performed in MEDLINE (PubMed), Embase, Web of Science, and the Cochrane Library. Primary outcome parameters were VGI, patency, and mortality. Pooled estimates of VGI were calculated using odds ratio (OR) and 95% confidence intervals (CIs) wherever possible. Quality assessment was performed with the Newcastle-Ottawa Assessment Scale and the Revised Cochrane risk of bias tool for randomised trials.

RESULTS

In total, 6 873 papers were identified. Only eight studies were included. Six of eight studies (75%) reported on known antimicrobial coating strategies such as antibiotics (n = 3) and silver (n = 3). In the other two studies, polymer coated grafts were used. Only three of eight studies compared coated with uncoated grafts (two antibiotic and one silver). Two randomised controlled trials reported on the effect of rifampicin soaked (1 mg/mL) grafts and showed no significant effect in the early (2 months; OR 0.69, 95% CI 0.29 - 1.62) or late (2 years; OR 0.73, 95% CI 0.23 - 2.32) post-operative periods. A retrospective cohort study focusing on the effect of silver coated grafts did not reveal any advantage (OR 0.19, 95% CI 0.02 - 1.64). Two polymer coated grafts were not considered to have a potential benefit in the prevention of VGIs.

CONCLUSION

Clinical studies reporting on the antibacterial effect of vascular graft coatings in the aortic position to prevent VGI are scarce. For silver and antibiotic coatings, no significant protection for VGI was observed. New types of grafts or long acting coating strategies are mandatory to prevent this complication in the future.

Comparison of Early and Mid-Term Outcomes After Fenestrated-Branched Endovascular Aortic Repair in Patients With or Without Prior Infrarenal Repair

OBJECTIVE

The purpose of this study was to compare short- and mid-term outcomes of fenestrated-branched endovascular repair (F-BEVAR) of pararenal (PRAA)/thoracoabdominal (TAAA) aortic aneurysms in patients with or without prior endovascular/open (EVAR/OAR) infrarenal aortic repair.

METHODS

Data from consecutive F-BEVAR (2010-2019) at two high-volume aortic centers were retrospectively reviewed. Primary endpoints were technical success, 30-day mortality, and overall survival. Secondary endpoints included 30-day major adverse events (MAE), freedom from type I/III endoleaks, reinterventions, sac expansion, and target vessel (TV) primary patency.

RESULTS

A total of 222 consecutive patients were included for analysis; of these 58 (26.1%) had prior infrarenal repair (EVAR=33, OAR=25) and 164 (73.9%) had native PRAA/TAAA. At baseline, patients with prior infrarenal repair were older (mean age=75.1 vs 71.6 years, p=.005) and the proportion of females was lower (8.6% vs 29.3%, p=.002). Technical success was 97.8% (n=217) in the entire cohort, without any significant differences between study groups (94.8% vs 98.8%, p=.08). At 30 days, there were no significant differences between patients with prior infrarenal repair as compared with those without in rate of MAE (44.8% vs 54.9%, p=.59). The 5-year estimate of survival for those who underwent native aortic repair was 61.6%, versus 61.3% for those who had a previous repair (p=.67). The 5-year freedom from endoleaks I/III estimates were significantly lower in patients who had prior infrarenal repair as compared with patients undergoing treatment of native aneurysms (57.1% vs 66.1%, p=.03), mainly owing to TV-related endoleaks (ie, type IC and/or IIIC endoleaks). No significant differences were found between study groups in rates of reinterventions and TV primary patency. Five-year estimates of freedom from sac increase >5mm were significantly lower in patients who received F-BEVAR after previous infrarenal repair as compared with those who underwent treatment of native aneurysms (48.6% vs 77.5%, p=.002).

CONCLUSIONS

F-BEVAR is equally safe and feasible for treatment of patients with prior infrarenal repair as compared with those undergoing treatment for native aneurysms. Increased rates of TV-related endoleaks were observed which could lead to lower freedom from aneurysm sac shrinkage during follow-up. Nevertheless, the 5-year rates of reinterventions and TV patency were similar, thereby indicating that overall effectiveness of treatment remained satisfactory at mid-term.

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.

Impact of proximal neck anatomy on short-term and mid-term outcomes after treatment of abdominal aortic aneurysms with new-generation low-profile endografts. Results from the multicentric "ITAlian north-east registry of ENDOvascular aortic repair with the BOltOn Treo endograft (ITA-ENDOBOOT)"

INTRODUCTION

The aim of the study was to evaluate the short-term and mid-term technical and clinical outcomes of the Bolton Treo endograft in subjects with abdominal aortic aneurysm (AAA) requiring endovascular aortic repair (EVAR) and assess if presence of hostile proximal neck would represent a risk factor for increased failure rates.

METHODS

A retrospective review of all consecutive patients who had undergone elective or non-elective EVAR with the Bolton Treo endograft at five institutions located in the North-East of Italy (January 2016-December 2020) was performed. The main exposure variable for this study was presence of hostile (HAN) or friendly (FAN) aortic neck.

RESULTS

A total of 137 consecutive patients were treated with the Bolton Treo endograft at participating institutions; of these 63 (46%) presented HAN while 74 (54%) had FAN. At baseline, no significant differences were observed in the distribution of demographics and comorbidities between study groups. Two type Ia endoleaks (EL) were detected at completion angiography, all in patients with HAN but none in patients with FAN (3% vs 0%, p=.04), but no type III EL were identified in the whole cohort. The median duration of follow-up in the study cohort was 30 months (IQR 22-34 months) and was similar between study groups (p=.87). At three-years, survival estimates were 89% and 91% (p=.82) in patients with HAN and FAN, respectively. At three years, patients with HAN had significantly lower freedom from type IA endoleak as compared with patients with FAN (87% vs 94%, p=.02). No significant differences were found between study groups in the three-year estimates of freedom from reinterventions (80% vs 86%, p=.28). Using cox proportional hazards, presence of type II EL (HR 3.15, 95%CI 1.18-8.5, p=.02) and presence of type IA EL (HR 4.22, 95%CI 1.39-12.85, p=.01) were found as independent predictors for reinterventions in univariate analysis, although they were no longer significant in the multivariate model. Freedom from sac increase >5mm at three years were not significantly different between study groups (92% vs 91%, p=.95).

CONCLUSIONS

Within a contemporary multicentric real-world experience, EVAR with the Bolton Treo endograft shows a satisfactory safety profile in the immediate postoperative phase and acceptable outcomes during mid-term follow-up. Presence of HAN is correlated with development of type Ia EL (either early following stent-graft implantation or late after EVAR) which, in turn, may represent a significant factor leading to reinterventions.

Successful management of infected right iliac pseudoaneurysm caused by penetration of migrated inferior vena cava filter: A case report

BACKGROUND

Indwelling inferior vena cava (IVC) filters might cause various complications, including filter penetration, filter fracture, filter migration, and thrombosis of the IVC. Penetration and migration complications are common, while a caudal migrated double-basket filter with associated infected iliac pseudoaneurysm has seldom been reported.

CASE SUMMARY

We report a 64-year-old female admitted for sudden onset of severe right abdominal pain after IVC filter placement for 3 mo. The patient had a history of failed endovascular IVC filter retrieval. Computed tomography showed that the retrieval hook of the filter penetrated the right common iliac artery and vein, leading to right iliac artery pseudoaneurysm accompanied by right ureteral obstruction with ipsilateral hydronephrosis, and bilateral iliac veins were occluded. Emergency open repair was performed to remove the IVC filter, the right iliac pseudoaneurysm, and the compromised segments of the iliac veins and IVC with right common iliac artery reconstruction. Staphylococcus aureus was isolated from the tissue culture. The patient was discharged on postoperative day 12 with anticoagulation therapy and antibiotic therapy after discharge. Six-month follow-up computed tomography revealed that the right common iliac artery was patent, and only mild hydronephrosis was detected.

CONCLUSION

An indwelling IVC filter, even ‘embedded’ within organized thrombus, could still cause life-threatening complications. Open procedures remain the last resort for IVC filters with severe complications.

Deep Femoral Vein Reconstruction for Abdominal Aortic Graft Infections is Associated with Low Aneurysm Related Mortality and a High Rate of Permanent Discontinuation of Antimicrobial Treatment

OBJECTIVE

Aortic prosthesis infection is a devastating complication of aortic surgery. In situ reconstruction with the neo-aorto-iliac system (NAIS) bypass technique has become increasingly used and is recommended in recent treatment guidelines. The main aim was to evaluate NAIS procedural outcomes when undertaken after previous open or endovascular aortic repair in Sweden.

METHODS

In this retrospective study, The National Quality Registry for Vascular Surgery (Swedvasc) was used to identify Swedish centres that offered the NAIS bypass procedure for aortic prosthesis infection between 2008 and 2018. Variables of special interest were procedural details, short and long term survival, renal and other complications, and the durtion of antimicrobial treatment.

RESULTS

Forty patients (36 males, four females [mean age 69 years], 32 open repairs, seven endovascular aortic repairs [EVAR] and one fenestrated EVAR; 21 presented with aorto-enteric fistula) operated on with NAIS bypass were reviewed. The median time from the primary aortic intervention to the NAIS bypass procedure was 32 months (range 0 - 252 months). Mean ± standard deviation operating time was 645 ± 160 minutes, mean blood loss was 6 277 ± 6 525 mL, mean length of intensive care unit stay was 5.3 ± 3.7 days, and mean length of overall hospital stay was 21.2 ± 11.4 days. Thirty-five patients (88%) had a positive microbial culture; the most commonly isolated pathogen was Candida spp. The majority of patients survived for 30 days (n = 35 [88%]), and 33 (83%) and 32 (80%) patients survived for 90 days and one year, respectively. The number of surviving patients free from antimicrobial treatment at 90 days, six months, and one year was 19 (58%), 29 (88%), and 30 (94%). After a mean long term follow up of 69.9 ± 44.7 months, 20 patients were still alive.

CONCLUSION

The NAIS bypass procedure offered reasonable survival and functional outcomes, and was associated with a high cure rate, defined as freedom from any antimicrobial treatment.

Guided Aspiration for Determining the Microbiological Aetiology of Aortic Vascular Graft and Endograft Infections

OBJECTIVE

Open and endovascular aortic repair may be complicated by aortic vascular graft or endograft infection (VGEI). Confirming the microbiological aetiology is a key element in providing the best available treatment to patients with a VGEI. The primary aim of this study was to describe the technique of direct aneurysm sac guided aspiration (DASGA) in determining the microbiological aetiology in a cohort of patients with VGEIs, and to report its diagnostic value.

METHODS

This was a retrospective observational single centre study performed between the years 2011 to 2020 in Malmö, Sweden. Patients with a suspected aortic VGEI, where a DASGA was performed at the Vascular Centre, were included in the study.

RESULTS

In total, 31 guided aspirations were performed in 27 patients (25 male [93%]; median age 77 years [range 57 - 82 years]). The combination of culture and 16S rRNA/18S rRNA gave a microbial aetiology in 25/31 (81%) DASGAs. Importantly, excluding three cases where infection was ruled out, this rate increases up to 89%. A polymicrobial aetiology was found in six (24 %) cases. The most common bacteria found were Cutibacterium spp. (n = 8) and Listeria monocytogenes (n = 4). In total, the dominant aetiology could be further characterised into normal gut flora (n = 12; 48%) or skin commensals (n = 8; 32%). No patients had persistent morbidity related to the DASGA.

CONCLUSION

DASGA can be used successfully to determine the microbiological aetiology of open and endovascular graft infections. This method appears to be safe, with a high success rate for confirming the microbiological aetiology of VGEIs, particularly if standard culturing methods are combined with 16S rRNA/18S rRNA. Finding the causative microbial aetiology is crucial, and in the vast majority of cases translumbar puncture can be used without serious complications.

[18F] FDG PET/CT can improve the diagnostic accuracy for aortic endograft infection

PURPOSE

Aortic endograft infection (EI) can result in potentially life-threatening vascular complications. Unfortunately, it is difficult to obtain a correct diagnosis at an early stage in many patients. This report aims at validating the use of [¹⁸F] FDG PET/CT imaging for suspected endograft infections in a prospectively collected cohort of patients treated with EVAR and TEVAR.

MATERIALS AND METHODS

During a 14-year period, 366 patients required aortic stent graft. All procedures were performed electively, except for one patient. Among these 366 patients, eleven patients (3%) were suspected to have aortic EI. Contrast-enhanced CT and FDG PET/CT were performed in all 11 patients. Medical charts and imaging were analysed for these 11 cases, with initial positive CT.

RESULTS

The final diagnosis of EI was established in seven (1,9%) based on clinical features, laboratory investigations and a significant [¹⁸F] FDG uptake in the aortic graft as well as the aortic wall. The median time from the initial EVAR/TEVAR to diagnosed infection was 180 days. During follow-up, the seven patients had a second PET/CT that was compared with the initial evaluation, decreased uptake was correlated with clinical improvement.

CONCLUSIONS

Contemporary diagnostic imaging for a potentially lethal endograft infection lacks precision, this observational study illustrates the potential clinical value of [¹⁸F] FDG PET/CT in the management of aortic EI. [¹⁸F] FDG PET/CT constitutes an imaging modality able to confirm the diagnosis, monitor disease progression as well as the effect of pharmaceutical treatment and detect relapse.

Dependent functional status rather than age is a better predictor of adverse outcomes after excision of an infected abdominal aortic graft

OBJECTIVE

The optimal management of infected abdominal aortic grafts is complete surgical excision plus in situ or extra-anatomic revascularization in patients who can tolerate this morbid operation. In addition to using age and the presence of comorbidities for risk assessment, physicians form a global clinical impression when deciding whether to offer excision or to manage conservatively. Functional status is a distinct objective measure that can inform this decision. This study examines the relative impact of age and functional status on outcomes of infected abdominal aortic graft excision to guide surgical decision-making.

METHODS

Current Procedural Terminology code 35907 was used to identify patients undergoing excision of infected abdominal aortic graft in the 2005 to 2017 American College of Surgeons - National Surgical Quality Improvement Program (NSQIP) database. Patients were stratified by the upper age quartile (75 years old) as a cutoff, and then by functional status, independent vs dependent (as defined by NSIQIP). The patients were then stratified into four groups: Younger (<75)/Independent, Younger (<75)/Dependent, Older (≥75)/Independent, and Older (≥75)/Dependent. Outcomes measured included 30-day mortality and major organ-system dysfunction.

RESULTS

There were 814 patients who underwent infected abdominal aortic graft excision: 508 patients (62%) were Younger/Independent, 89 patients (11%) were Younger/Dependent, 176 patients (22%) were Older/Independent, and 41 patients (5%) were Older/Dependent. There was no statistically significant difference in 30-day mortality for Younger/Dependent (odds ratio [OR], 1.66; 95% confidence interval [CI], 0.90-3.09; P = .536) or Older/Independent (OR, 1.31; 95% CI, 0.78-2.19; P = .311) patients when compared with Younger/Independent patients, which suggests that neither old age nor dependent functional status by itself adversely affects mortality. However, when both factors were present, Older/Dependent patients had three times higher mortality when compared with Younger/Independent patients (41.5% vs 13.4%, respectively; OR, 3.13; 95% CI, 1.46-6.71; P = .003). Furthermore, as long as patients presented with independent functional status, old age by itself did not adversely affect major organ-system dysfunction (ORs for Older/Independent vs Younger/Independent were 0.76 [P = .454], 1.04 [P = .874], and 0.90 [P = .692] for cardiac, pulmonary, and renal complications, respectively). On the contrary, even in younger patients, dependent functional status was significantly associated with higher pulmonary complications (Younger/Dependent vs Younger/Independent: OR, 2.22; 95% CI, 1.33-3.73; P = .002) and higher rates of unplanned reoperation (OR, 2.67; 95% CI, 1.62-4.41; P < .0001).

CONCLUSIONS

Dependent functional status has significant association with adverse outcomes after excision of infected abdominal aortic grafts, whereas old age alone does not. Therefore, this procedure could be considered in appropriately selected elderly patients with otherwise good functional status. However, caution should be applied in dependent patients regardless of age due to the risk of pulmonary complications.

Management and Outcomes of Proximal Aortic Graft Infection: A Systematic Review

OBJECTIVE

Proximal aortic graft infection (PAGI) is a rare but often fatal postoperative complication. Its management often relied on surgical preferences and resource availability of each centre, until the recent unifying guidelines published by the European Society for Vascular Surgery (ESVS). This paper aimed to amalgamate the published experience in managing PAGI and their outcomes.

METHODS

PubMed, Scopus and Cochrane Library databases were searched systematically. All primary studies besides single-patient case reports were included. Data extracted included study and patient characteristics, type of index surgery, type of microorganisms involved, definitive treatment modality, and any outcome measures reported.

RESULTS

Of the 20 studies included, 157 of the 290 PAGI patients underwent complete graft explantation and replacement, 106 underwent graft-preservation interventions (debridement and/or irrigation), and 25 had antibiotics alone. Adjunctive interventions included graft coverage, vacuum-assisted closure, use of infection-resistant graft materials, and lifelong suppressive therapy. In-hospital mortality was 20.8% (n=60), with postoperative sepsis and multiorgan failure (n=24) being the most common cause. Recurrent infection occurred in 10 post-discharge patients. Post-discharge mortality rate was 11.4% (n=33), with cardiac complications and stroke being the most common cause in surgically-treated and medically-treated patients, respectively.

CONCLUSIONS

Given the risk of mortality, the management approach of PAGI highly depends on the fitness of the patient. We believe that early referral to specialised aortic centres is essential to plan for optimal management strategies and improve patient outcomes. Further studies are also required to parse out the most effective adjunctive interventions to maximise patient outcomes.

Fifteen-year, single-center experience with in situ reconstruction for infected native aortic aneurysms

OBJECTIVE

The purpose of the present study was to evaluate the survival and freedom from reinfection for patients with infected native aortic aneurysms (INAAs) treated with in situ revascularization (ISR), using either open surgical repair (OSR) or endovascular aneurysm repair (EVAR), and to identify the predictors of outcome.

METHODS

Patients with INAAs who had undergone ISR from January 2005 to December 2020 were included in the present retrospective single-center study. The diagnosis of INAAs required a combination of two or more of the following criteria: (1) clinical presentation, (2) laboratory results, (3) imaging findings, and (4) intraoperative findings. The primary endpoint was 30-day mortality. The secondary endpoints were in-hospital mortality, estimated survival, patency, and freedom from reinfection using the Kaplan-Meier method. The predictive factors for adverse outcomes were evaluated using the Mann-Whitney U test or the Fisher exact test and multivariate regression analysis.

RESULTS

A total of 65 patients (53 men [81.5%]; median age, 69.0 years; interquartile range, 61.5-75.0 years) were included, 31 (47.7%) were immunocompromised, 60 were symptomatic (92.3%), and 32 (49.2%) had presented with rupture, including 3 aortocaval fistulas (4.6%) and 12 aortoenteric fistulas (18.5%). The most common location was infrarenal (n = 39; 60.0%). Of the 65 patients, 55 (84.6%) had undergone primary OSR with ISR, 3 (4.6%) had required EVAR as a bridge to OSR, and 8 (12.3%) had undergone EVAR as definitive treatment. The approach was a midline laparotomy for 44 patients (67.7%), mostly followed by reconstruction and aortic-aortic bypass (n = 28; 40.6%) and the use of a silver and triclosan Dacron graft (n = 30; 43.5%). Causative organisms were identified in 55 patients (84.6%). The 30-day and in-hospital mortality rates were 6.2% (n = 4) and 10.8% (n = 7). The median follow-up was 33.5 months (interquartile range, 13.6-62.3 months). The estimated 1- and 5-year survival rates were 79.7% (95% confidence interval [CI], 67.6%-87.7%) and 67.4% (95% CI, 51.2%-79.3%). The corresponding freedom from reinfection rates were 92.5% (95% CI, 81.1%-97.1%) and 79.4% (95% CI, 59.1%-90.3%). On multivariate analysis, in-hospital mortality increased with uncontrolled sepsis (P < .0001), rapidly expanding aneurysms (P = .008), and fusiform aneurysms (P = .03). The incidence of reinfection increased with longer operating times (P = .009).

CONCLUSIONS

The selective use of ISR and OSR combined with targeted antimicrobial therapy functioned reasonably well in the treatment of INAAs, although larger, prospective, multicenter studies with appropriately powered comparative cohorts are necessary to confirm our findings and to determine the best vascular substitute and precise role of EVAR as a bridge to OSR or definitive treatment.