The incidence and factors associated with graft infection after aortic aneurysm repair

Early and Mid-Term Results of Native and Abdominal Aortic Graft Infection Treatment via Surgeon-Constructed Porcine Pericardial Aortic Tubes

The search for optimal material for aortic infection reconstruction is ongoing. Our study presents the early and mid-term results of surgeon-constructed porcine pericardial tubes in the in-situ reconstruction of abdominal aortic infections, focusing on the safety as well as the durability of surgeon-created tubes. We performed a retrospective analysis of 8 patients treated for native aortic (n = 3) and aortic graft infections (n = 5) with surgeon-created tubes made of porcine pericardium patch (8 × 14 cm NO-REACT Ⓡ, BioIntegral Surgical Inc., Mississauga, ON, Canada). There were 7 males and 1 female, aged 68.5 (±4.8 years). Three patients had an aorto-enteric fistula. Technical success was obtained in all patients. Thirty-day mortality was 12.5% (n = 1). Mid-term follow-up was 12 months (2-63 months). One-year mortality was 37.5% (n = 3). Reintervention rate was 28.5% (n = 2). False aneurysm rate in the follow-up was 14.2% (n = 1). Surgeon-constructed porcine pericardial tubes seem to be a promising alternative as a replacement for native as well as graft-related abdominal aortic infections. The mid-term durability is encouraging, once the infection is controlled in cases with successful fistula repair and in native aortic infections patients. Further observations on larger groups, in longer follow-ups are necessary to confirm these preliminary observations.

Fostering Collaborative Teamwork-A Comprehensive Approach to Vascular Graft Infection Following Arterial Reconstructive Surgery

Vascular graft infection (VGI) is one of the most serious complications following arterial reconstructive surgery. VGI has received increasing attention over the past decade, but many questions remain regarding its diagnosis and management. In this review, we describe our approach to VGI through multidisciplinary collaboration and discuss decision making for challenging presentations. This review will concentrate on VGI that impacts both aneurysms and pseudoaneurysms excluding the ascending thoracic aorta.

Characteristics and Outcome of Vascular Graft Infections: A Risk Factor and Survival Analysis

Background

Vascular graft infection (VGI) is a serious complication after implantation of arterial vascular grafts. Optimal surgical and pathogen-specific antimicrobial treatment regimens for VGI are largely unknown. We evaluated patients with arterial VGI according to onset, location, microbiological and imaging characteristics, and surgical and antimicrobial treatment and performed an outcome evaluation.

Methods

Consecutive patients with VGI treated in 2 hospitals from 2010 through 2020 were retrospectively analyzed. Uniform definition criteria and standardized outcome evaluation were applied. Logistic regression was used for multiple analysis; survival analysis was performed with Kaplan-Meier analysis and a log-rank test.

Results

Seventy-eight patients with VGI were included: 30 early-onset cases (<8 weeks after graft implantation) and 48 late-onset cases, involving 49 aortic and 29 peripheral grafts. The median time from initial implantation to diagnosis of VGI was significantly longer in aortic than peripheral VGIs (363 vs 56 days, P = .018). Late-onset VGI (odds ratio [OR], 7.3; P = .005) and the presence of surgical site infection/complication (OR, 8.21; P = .006) were independent risk factors for treatment failure. Surgical site infection/complication was associated with a higher risk for early-onset VGI (OR, 3.13; P = .040). Longer infection-free survival was observed in cases where the infected graft was surgically removed (P = .037).

Conclusions

This study underlines the importance of timely diagnosis of VGI and preventing surgical site infections/complications at graft implantation. It highlights the complexity of infection eradication, especially for late-onset infections, and the importance of adequate antimicrobial and surgical treatment.

Exploiting endovascular aortic repair as a minimally invasive method - Nine years of experience in a non-university hospital

Background

At the introduction of endovascular aortic repair (EVAR) in 2013 in our non-university hospital, we established a quality registry to monitor our EVAR activity.

Purpose

To observe if we over time were able to exploit EVAR as a minimally invasive method in an elective as well as emergency setting, and to monitor our treatment quality in terms of complications, secondary interventions and mortality.

Material and methods

From November 2013 to March 2022, we treated 207 patients with EVAR, including six patients with rupture. Follow-up regimen was partly based on contrast-enhanced computer tomography, and partly on contrast-enhanced ultrasound in combination with plain radiography.

Results

During the observation period, the method of anesthesia changed from general, via spinal, to local anesthesia. The groin access changed from surgical cut down to percutaneous and the median length of postoperative stay decreased from 3 days to 1 day. EVAR on ruptured aneurysm was done for the first time in 2019. Endoleak was detected in 85 patients (42%) and 37 patients (18%) had one or more secondary interventions, of which 85% were endovascular. Estimated five-year survival was 72% in patients below 80 years of age and 45% in patients 80 years or older.

Conclusion

Nine years of experience enabled us to exploit EVAR's advantages as a minimally invasive method in an elective as well as emergency setting. Complications, secondary interventions and survival rates in our low volume non-university hospital matches results from larger vascular centers.

Biofilm formation on endovascular aneurysm repair (EVAR) grafts-a proof of concept in vitro model

OBJECTIVES

An endovascular aneurysm repair (EVAR) graft is a catheter-implanted vascular prosthesis and is the preferred treatment for patients with aortic aneurysm. If an EVAR graft becomes the focus of infection, the treatment possibilities are limited because it is technically difficult to remove the graft to obtain source control. This study examines whether Pseudomonas aeruginosa and Staphylococcus aureus form biofilm on EVAR prostheses.

METHODS

EVAR graft sections were exposed to bacteria at 102 or 108 colony forming units (CFU)/mL in lysogeny broth and Krebs-Ringer at 37°C, bacterial biofilm formation was evaluated by scanning electron microscopy and counting CFU on the graft sections after antibiotic exposure at × 10 minimal inhibitory concentration. Bacteria were tested for tolerance to benzylpenicillin, tobramycin, and ciprofloxacin.

RESULTS

Bacterial exposure for 15 minutes established biofilms on all prosthesis fragments (6/6 replicates). After 4 hours, bacteria were firmly attached to the EVAR prostheses and resisted washing. After 18-24 hours, the median CFU/g of EVAR graft reached 5.2 × 108 (1.15 × 108-1.1 × 109) for S. aureus and 9.1 × 107 (3.5 × 107-6.25 × 108) for P. aeruginosa. Scanning electron microscopy showed bacterial attachment to the graft pieces. There was a time-dependent development of tolerance with approximately 20 (tobramycin), 560 (benzylpenicillin), and 600 (ciprofloxacin) times more S. aureus surviving antibiotic exposure in 24- compared with 0-hour-old biofilm. Five (tobramycin) and 170 times (ciprofloxacin) more P. aeruginosa survived antibiotic exposure in 24- compared with 0-hour-old biofilms.

DISCUSSION

Our results show that bacteria can rapidly adhere to and subsequently form antibiotic-tolerant biofilms on EVAR graft material in concentrations equivalent to levels seen in transient bacteraemia in vivo. Potentially, the system can be used for identifying optimal treatment combinations for infected EVAR prosthesis.

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.

Incidence and Outcomes of Bloodstream Infection After Arterial Aneurysm Repair: Findings From a Population-Based Study

Background

Limited research has focused on bloodstream infection (BSI) in patients with arterial grafts. This study aims to describe the incidence and outcomes of BSI after arterial aneurysm repair in a population-based cohort.

Methods

The expanded Rochester Epidemiology Project (e-REP) was used to analyze aneurysm repairs in adults (aged ≥18 years) residing in 8 counties in southern Minnesota from January 2010 to December 2020. Electronic records were reviewed for the first episode of BSI following aneurysm repair. BSI patients were assessed for vascular graft infection (VGI) and followed for all-cause mortality.

Results

During the study, 643 patients had 706 aneurysm repairs: 416 endovascular repairs (EVARs) and 290 open surgical repairs (OSRs). Forty-two patients developed BSI during follow-up. The 5-year cumulative incidence of BSI was 4.7% (95% confidence interval [CI], 3.0%-6.4%), with rates of 4.0% (95% CI, 1.8%-6.2%) in the EVAR group and 5.8% (95% CI, 2.9%-8.6%) in the OSR group (P = .052). Thirty-nine (92.9%) BSI cases were monomicrobial, 33 of which were evaluated for VGI. VGI was diagnosed in 30.3% (10/33), accounting for 50.0% (8/16) of gram-positive BSI cases compared to 11.8% (2/17) of gram-negative BSI cases (P = .017). The 1-, 3-, and 5-year cumulative post-BSI all-cause mortality rates were 22.2% (95% CI, 8.3%-34.0%), 55.8% (95% CI, 32.1%-71.2%), and 76.8% (95% CI, 44.3%-90.3%), respectively.

Conclusions

The incidence of BSI following aneurysm repair was overall low. VGI was more common with gram-positive compared to gram-negative BSI. All-cause mortality following BSI was high, which may be attributed to advanced age and significant comorbidities in our cohort.

Brazilian Society for Angiology and Vascular Surgery guidelines on abdominal aortic aneurysm

The Brazilian Society of Angiology and Vascular Surgery, through the Guidelines Project, presents new Abdominal Aortic Aneurysm Guidelines, on the subject of care for abdominal aortic aneurysm patients. Its development prioritized descriptive guidelines, using the EMBASE, LILACS, and PubMed databases. References include randomized controlled trials, systematic reviews, meta-analyses, and cohort studies. Quality of evidence was evaluated by a pair of coordinators, aided by the RoB 2 Cochrane tool and the Newcastle Ottawa Scale forms. The subjects include juxtarenal aneurysms, infected aneurysms, and new therapeutic techniques, especially endovascular procedures. The current version of the guidelines include important recommendations for the primary topics involving diagnosis, treatment, and follow-up for abdominal aortic aneurysm patients, providing an objective guide for medical practice, based on scientific evidence and widely available throughout Brazil.

Aortic endograft infection by Mycobacterium abscessus subsp. massiliense with acquired clarithromycin resistance: a case report

BACKGROUND

Mycobacterium abscessus subsp. massiliense (MMA) comprises a group of non-tuberculous, rapidly growing mycobacteria. Although MMA can cause pulmonary diseases, surgical site infections, and disseminated diseases, aortic endograft infection has not been reported. Here, we describe the first case of aortic endograft infection caused by MMA.

CASE PRESENTATION

Two months after stent-graft insertion for an abdominal aortic aneurysm, an 85-year-old man was admitted with fever and abdominal pain and was diagnosed with aortic endograft infection. Despite 14 days of meropenem and vancomycin intravenous administration, periaortic fluid pooling increased as compared to that before antibiotic administration. The abscess was drained, and fluorescent acid-fast staining of the abscess fluid revealed bacilli. We conducted genetic tests on the genes hsp65, rpoB, and sodA, performed Whole Genome Sequencing (WGS), and identified the organism as MMA. Intravenous imipenem-cilastatin (IPM/CS), amikacin (AMK), and oral clarithromycin (CAM) were administered. After 2 months, oral CAM and sitafloxacin were administered because the abscess had decreased in size. However, after 6 weeks, the abscess increased in size again. Antimicrobial susceptibility testing of the drainage fluid from the abscess resulted in the isolation of an MMA strain that had acquired resistance to CAM. Intravenous IPM/CS, AMK, and oral linezolid were added to the treatment regimen along with oral CAM and STFX. However, he was not fully cured and died 6 months later. Neither the full-length erythromycin ribosome methyltransferase (erm)(41) gene nor the rrl or rpIV gene mutations were found by Sanger sequencing in the pre- and post-treatment strains. Whole-genome sequence analysis of the post-treatment strain revealed mutations in genes with no previous reports of association with macrolide resistance.

CONCLUSIONS

Aortic endograft infection caused by MMA strain is extremely rare; nonetheless, MMA should be suspected as the causative microorganism when broad-spectrum antimicrobials are ineffective.

Management of secondary aorto-enteric fistulae: a multi-centre study

BACKGROUND

Secondary aorto-enteric fistulae (SAEF) are a rare, complex and life-threatening complication following aortic repair. Traditional treatment strategy has been with open aortic repair (OAR), with emergence of endovascular repair (EVAR) as a potentially viable initial treatment option. Controversy exists over optimal immediate and long-term management.

METHODS

This was a retrospective, observational, multi-institutional cohort study. Patients who had been treated for SAEF between 2003 and 2020 were identified using a standardized database. Baseline characteristics, presenting features, microbiological, operative, and post-operative variables were recorded. The primary outcomes were short and mid-term mortality. Descriptive statistics, binomial regression, Kaplan-Meier and Cox age-adjusted survival analyses were performed.

RESULTS

Across 5 tertiary centres, a total of 47 patients treated for SAEF were included, 7 were female and the median (range) age at presentation was 74 years (48-93). In this cohort, 24 (51%) patients were treated with initially with OAR, 15 (32%) with EVAR-first and 8 (17%) non-operatively. The 30-day and 1-year mortality for all cases that underwent intervention was 21% and 46% respectively. Age-adjusted survival analysis revealed no statistically significant difference in mortality in the EVAR-first group compared to the OAR-first group, HR 0.99 (95% CI 0.94-1.03, P = 0.61).

CONCLUSION

In this study there was no difference in all-cause mortality in patients who had OAR or EVAR as first line treatment for SAEF. In the acute setting, alongside broad-spectrum antimicrobial therapy, EVAR can be considered as an initial treatment for patients with SAEF, as a primary treatment or a bridge to definitive OAR.

Paracolic Gutter Routing: A Novel Retroperitoneal Extra-Anatomical Repair for Infected Aorto-Iliac Axis

OBJECTIVE

We describe and analyze outcomes of a novel extra-anatomical paracolic gutter routing technique for surgical repair of aorto-iliac infections.

METHODS

A double-center, observational, cohort study of all consecutive patients with aorto-iliac infections treated using extra-anatomical paracolic gutter technique. Between May 2015 and December 2022, six patients with aorto-iliac infections were treated with the paracolic gutter routing technique. Cases were identified retrospectively in an institutional database, and data were retrieved from surgical records, imaging studies, and follow-up records.

RESULTS

Aorto-bifemoral vascular reconstructions were performed using this technique in six patients. During mean follow-up of 52 ± 44 months, there was one case of graft thrombosis (17%) with subsequent successful thrombectomy. Primary and secondary graft patency rates were 83% and 100%, respectively. There was one mortality (17%) due to candida sepsis. All graft prostheses were patent at last follow-up.

CONCLUSIONS

The paracolic gutter technique is a useful technique in patients with extensive aorto-iliac infections, arteriovenous and iliac-ureteric fistulas, or at a high risk of vascular graft infection and is associated with favorable reinfection and patency rates.

Vascular Graft Infection After Aneurysm Repair: A Population-Based Study

OBJECTIVE

To describe the incidence, epidemiology, and outcomes of vascular graft infection (VGI) in a population-based study in southern Minnesota.

PATIENTS AND METHODS

Retrospective review of all adult patients from 8 counties who underwent arterial aneurysm repair between January 1, 2010, and December 31, 2020. Patients were identified through the expanded Rochester Epidemiology Project. The Management of Aortic Graft Infection Collaboration criteria were used to define VGI.

RESULTS

A total of 643 patients underwent 708 aneurysm repairs: 417 endovascular (EVAR) and 291 open surgical (OSR) repairs. Of these patients, 15 developed a VGI during median follow-up of 4.1 years (interquartile range, 1.9-6.8 years), corresponding to a 5-year cumulative incidence of 1.6% (95% CI, 0.6% to 2.7%). The cumulative incidence of VGI 5 years after EVAR was 1.4% (95% CI, 0.2% to 2.6%) compared with 2.0% (95% CI, 0.3% to 3.7%) after OSR (P=.843). Of the 15 patients with VGI, 12 were managed conservatively without explantation of the infected graft/stent. Ten died during median follow-up from VGI diagnosis of 6.0 years (interquartile range, 5.5-8.0 years), including 8 of the 12 patients treated conservatively.

CONCLUSION

The VGI incidence in this study was overall low. There was no statistically significant difference in VGI incidence after OSR and EVAR. The all-cause mortality rate after VGI was high and reflected an older cohort with multiple comorbid conditions.

Surgical Repair of Abdominal Aorto-Iliac Prosthetic Graft Infections: A Nationwide Japanese Cohort Study

OBJECTIVE

Prosthetic graft infection (PGI) after open abdominal aortic and iliac artery reconstruction is life threatening. However, because it is rare and frequently difficult to diagnose, robust evidence on its treatment and optimal management strategies are lacking. This study aimed to clarify the clinical characteristics and surgical treatment outcomes of this condition and to identify pre-operative and operative factors affecting its prognosis.

METHODS

This was a nationwide cohort study. Using a nationwide clinical registry system, patients who were treated surgically for PGI after open abdominal aortic and iliac artery reconstruction between 2011 and 2017 were investigated, and their profiles and clinical courses were analysed. The relationships between the pre-operative and operative factors and the post-operative outcomes, including death and persistent or recurrent graft related infection, were evaluated.

RESULTS

The study included 213 patients. The median duration between the index arterial reconstruction and surgical treatment for PGI was 644 days. Fistula development to the gastrointestinal tract was confirmed during surgery in 53.1% of patients. The cumulative overall survival rates at 30 and 90 days, one, three, and five years were 87.3%, 74.8%, 62.2%, 54.5%, and 48.1%, respectively. Pre-operative shock was the only factor independently associated with 90 day and three year death. Short term and late mortality rates, as well as the rate of persistent or recurrent graft related infection, did not differ significantly between patients treated with total removal of the infected graft and those treated with partial removal of the graft.

CONCLUSION

Surgery for PGI after open reconstruction of the abdominal aorta and iliac arteries is complex, and the post-operative mortality rate remains high. Partial removal of the infected graft may be an alternative in selected patients with limited extent of infection.

The anesthesiologist's perspective on emergency aortic surgery: Preoperative optimization, intraoperative management, and postoperative surveillance

The management of emergencies related to the aorta requires a multidisciplinary approach involving various health care professionals. Despite technological advancements in treatment methods, the risks and mortality rates associated with surgery remain high. In the emergency department, definitive diagnosis is usually obtained through computed tomography angiography, and management focuses on controlling blood pressure and treating symptoms to prevent further deterioration. Preoperative resuscitation is the main focus, followed by intraoperative management aimed at stabilizing the patient's hemodynamics, controlling bleeding, and protecting vital organs. After the operation, factors such as organ protection, transfusion management, pain control, and overall patient care must be taken into account. Endovascular techniques are becoming more common in surgical treatment, but they also present new challenges in terms of complications and outcomes. It is recommended that patients with suspected ruptured abdominal aortic aneurysms be transferred to facilities with both open and endovascular treatment options and a track record of successful outcomes to ensure the best patient care and long-term results. To achieve optimal patient outcomes, close collaboration and regular case discussions between health care professionals are necessary, as well as participation in educational programs to promote a culture of teamwork and continuous improvement.

Conservative Management First Strategy in Aortic Vascular Graft and Endograft Infections

OBJECTIVE

The aim of this study was to describe and present the outcomes of a specific treatment protocol for aortic vascular graft and endograft infections (VGEIs) without explantation of the infected graft.

METHODS

This was a retrospective, observational single centre cohort study carried out between 2012 and 2022 at a tertiary hospital. An aortic VGEI was defined according to the Management of Aortic Graft Infection Collaboration (MAGIC) criteria. Fitness for graft excision was assessed by a multidisciplinary team and included an evaluation of the patient's general condition, septic status, and anatomical complexity. Antimicrobial treatments were individualised. The primary outcome was survival at the last available follow up; secondary outcomes were antimicrobial treatment duration, infection eradication, treatment failure despite antimicrobial treatment, and the development of aortic fistulation.

RESULTS

Fifty patients were included in the study, of whom 42 (84%) had had previous endovascular repair. The median patient age was 72 years (range 51 - 82 years) and median duration of treatment with antimicrobials was 18 months (range 1 - 164 months). Kaplan-Meier analysis estimated the 30 day survival to be 98% (95% confidence interval [CI] 96 - 100), the one year survival rate to be 88% (95% CI 83.4 - 92.6), and the three year survival rate to be 79% (95% CI 72.7 - 84.7). Twenty-four (48%) patients were able to discontinue antibiotic treatment after a median of 16 months (range 4 - 81 months). When categorised according to infected graft location, deaths occurred in four (40%) patients with thoracic, two (40%) with paravisceral, seven (30%) with infrarenal VGEIs, and in one (25%) patient with an aorto-iliac VGEI; no (0%) patient with a thoraco-abdominal VGEI died.

CONCLUSION

Identifying the microbiological aetiology in patients with aortic VGEI enables individualised, specific antibiotic treatment, which may be useful in patients with a VGEI excluded from surgery. This single centre retrospective analysis of patients with VGEIs without fistula selected for conservative treatment suggests that conservative management of aortic VGEIs with targeted antibiotic therapy without graft excision is potentially effective, and that antimicrobial treatment will not necessarily be needed indefinitely.

Reconstruction of primary and secondary aortic infections with an antimicrobial graft

INTRODUCTION

In situ reconstruction (ISR) with autologous veins is the preferred method in infectious native aortic aneurysms (INAAs) or vascular (endo)graft infection (VGEI). However, access to biological substitutes can prove difficult and lacks versatility. This study evaluates survival and freedom from reinfection after ISR of INAA/VGEI using the antimicrobial Intergard Synergy graft combining silver and triclosan.

METHODS

From February 2014 to April 2020, 86 antimicrobial grafts were implanted for aortic infection. The diagnosis of INAA/VGEI and reinfection was established based on the Management of Aortic Graft Infection Collaboration criteria. Survival was analyzed using the Kaplan-Meier method and log-rank P values.

RESULTS

The antimicrobial graft was implanted in 32 cases of INAA, 28 of VGI, and 26 of VEI. The median age was 69.0 (interquartile range: 62.0; 74.0), with a history of coronary artery disease (n = 21; 24.4%), chronic kidney disease (n = 11; 12.8%), cancer (n = 21; 24.4%), and immunosuppression (n = 27; 31.4%). Imaging showed infiltration (n = 14; 16.3%), air (n = 10; 11.6%), and rupture (n = 16; 18.6% including 22 aortoenteric fistulae [AEnF]). Symptoms included fever (n = 37; 43.0%), shock (n = 11; 12.8%), and pain (n = 47; 54.7%). Repair was undertaken through a midline laparotomy in 75 cases (87.2%) and coeliac cross-clamping in 19 (22.1%), suprarenal in 26 (30.2%), plus celiac trunk (n = 3), mesenteric (n = 5), renal (n = 13), or hypogastric (n = 4) artery reconstruction, and omental flap coverage (n = 41; 48.8%). For AEnF, the gastrointestinal tract was repaired using direct suture (n = 14; 16.3%) or resection anastomosis (n = 8; 9.3%). Causative organisms were identified in 74 patients (86.0%), with polymicrobial infection in 32 (37.2%) and fungal coinfection in 7 (8.1%). Thirty-day and in-hospital mortality were 14.0% and 22.1% (n = 12 and 19, respectively, 3 INAA [9.4%], 7 VGI [25.0%], and 9 VEI [34.6%]). Seventy patients (81.4%) had a postoperative complication, 44 (51.2%) of whom returned to the operative room. The 1- and 2-year survival rates were 74.0% (95% confidence interval [CI]: 63.3-82.1) and 69.8% (95% CI: 58.5-78.5), respectively. Survival was significantly better for INAA vs VGEI (P = .01) and worse for AEnF (P = .001). Freedom from reinfection was 97.2% (95% CI: 89.2-99.3) and 95.0% (95% CI: 84.8-98.4) with six reinfections (7.0%) requiring two radiological/six surgical drainage and two graft removals. Primary patency was 88.0% (95% CI: 78.1-93.6) and 79.9% (95% CI: 67.3-88.1) with no significant difference between INAA and VGEI (P = .16).

CONCLUSIONS

ISR of INAA or VGEI with the antimicrobial graft showed encouraging early mortality, comparable to the rates found in femoral vein (9%-16%) and arterial allograft (8%-28%) studies, as well as mid-term reinfection. The highest in-hospital mortality was noted for VEI including nearly 50% of AEnF.

Outcomes Following in Situ Reconstruction for Aortic Infection with the Neo-Aortoiliac System and Aortic Homograft

BACKGROUND

In situ reconstruction is one of the primary surgical options for primary aortic and graft and endograft infections. One institution's outcomes following aortic reconstruction with femoro-popliteal vein (i.e., the neo-aortoiliac system) and cryopreserved aortic allografts are described.

METHODS

A retrospective review was performed of any patient who underwent aortic reconstruction with femoropopliteal vein or cryopreserved aortic allograft from 2013-2022 at a single tertiary-care institution.

RESULTS

Twenty four patients underwent in situ reconstruction with the neo-aortoiliac system or with cadaveric allograft for primary or secondary aortic infection from 2013-2022. Short-term (30-day) mortality remains low (3/24 or 12.5%) despite the high incidence of major postoperative complications that necessitated reintervention in 11/24 or 45.8% of the cohort, most often for recurrent intracavitary infection. Gram-negative and drug-resistant pathogens were the most commonly implicated organisms in recurrent intra-abdominal infection. Management of early allograft degeneration is also described with extra-anatomic bypass grafting, conduit/graft embolization, which is then followed by allograft explantation and wide surgical debridement. Despite low short-term (30-day) mortality, all-cause 1-year mortality remains elevated at 38.1% (8/21) in those with an adequate follow-up interval.

CONCLUSIONS

In situ reconstruction for primary or secondary aortic infections results in excellent short-term patient outcomes but is characterized by a high incidence of reintervention and an elevated all-cause 1-year mortality.

COVID-19 induced aorto duodenal fistula following evar in the so called "negative" patient

OBJECTIVES

Since October 2019, SARS-CoV-2 pandemic represents a challenge for the international healthcare system and for the treatment and survival of patients. We normally focus on symptomatic patients, and symptoms can range from the respiratory to the gastrointestinal system. In addition, we consider patients without fever and respiratory symptoms, with both a negative RT nasopharyngeal swab and lung CT, as a "Covid-19 negative patient." In this article, we present a so called Covid-19 "negative" patient, with an unsuspected vascular clinical onset of the viral infection.

METHODS

An 80 y.o. man, who previously underwent endovascular aortic repair for an infrarenal abdominal aortic aneurysm, presented to our department with an atypical presentation of an aorto-enteric fistula during the pandemic. While in hospital, weekly nasopharyngeal swab tests were always negative for SARS-CoV-2. However, the absence of aortic endograft complications, the gross anatomy of duodenal ischemic injury, and the recent history of the patient who lived the last months in Bergamo, the Italian city with the highest number of COVID-19 deaths, lead the senior Author to suspect an occult SARS-CoV-2 infection. The patient underwent to resection of the fourth portion of the duodenum and the first jejunal loop, with subsequent duodenum-jejunal latero-lateral anastomosis and the direct suture of the aortic wall. The intestinal specimen was investigated as suspected SARS-CoV-2 bowel infection by the means of immune-histochemistry (IHC). An ileum sample obtained in the pre-COVID-19 era was used as a control tissue.

RESULTS

The histological analysis of the bowel revealed sustained wall ischemia and liponecrosis of the duodenal wall, with intramural blood vessels thrombosis. Blood vessel endotheliitis and neo-angiogenesis were also observed. Finally, the IHC was strongly positive for SARS-CoV-2 RNA and for HLA-G presence, with a particular concentration both in blood vessels and in the intestinal villi. The control tissue sample was not positive for both SARS-CoV-2 and HLA-G.

CONCLUSIONS

Coronavirus pandemic continues to be an international challenge and more studies and trials must be done to learn its pathogenesis and its complications. As for thromboembolic events caused by SARS-COV-2, vascular surgeons are involved in treatment and prevention of the complications of this syndrome and must be ready with general surgeons to investigate atypical and particular cases such as the one discussed in this article.

Referral Centre Experience with Infected Abdominal Aortic Endograft Explantation

OBJECTIVE

The increasing use of endovascular aneurysm repair (EVAR) appears to be associated with the burden of vascular endograft infections. Complete stent graft explantation is recommended but leads to significant mortality. This study aimed to assess the technical challenges, complications, and mortality rate following infected endograft explantation.

METHODS

Patients who underwent abdominal aortic endograft explantation for infection at the Bordeaux University Hospital from July 2008 to December 2020 were included retrospectively in this single centre observational study. The diagnosis was established based on the MAGIC criteria. The primary endpoint was 30 day mortality. Secondary endpoints were 90 day and in hospital mortality, survival, and re-infection.

RESULTS

Thirty-four patients were included, median age 69 years (interquartile range [IQR] 65, 76), with four (12%) treated as an emergency. The median time from EVAR to explantation was 17.5 months (4.5 - 36.3). In situ reconstruction was carried out with prosthetic grafts in 24 patients (71%, including 23 antimicrobial grafts combining silver and triclosan), and biological grafts in 10 (five femoral veins, four arterial allografts, three bovine patches, one biosynthetic graft). Seventeen aorto-enteric fistulae (AEnF) were addressed with direct repair of the intestinal tract (n = 10/17; 59%) or resection and anastomosis (n = 7/17; 41%). The culture was polymicrobial in 12 patients (35%) and remained sterile in four (12%). The 30 day and in hospital mortality rates were 21% (n = 7) and 27% (n = 9). Twenty-five patients (73%) presented with early post-operative complications, requiring 16 revision procedures (47%). Over a median follow up of 16.2 months (IQR 8.3, 33.6), the mortality rate was 35% (n = 12; 11 aortic related; 32%), with two re-infections (6%), both after biological reconstruction (one for an AEnF).

CONCLUSION

Early morbidity and mortality remain high after complete infected endograft explantation, even in a high volume centre. Comparison with other treatment modalities in large multicentre cohorts might be of interest.

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.

Ovine Biosynthetic Grafts for Aortoiliac Reconstructions in Nonsterile Operative Fields

BACKGROUND

Prosthetic vascular grafts placed surgically or via endovascular techniques can be subject to the risk of life-threatening graft infections. The Omniflow II vascular prosthesis is a biosynthetic graft that was reported to have favorable properties in resisting infections.

MATERIALS AND METHODS

We retrospectively reviewed our 3 years' experience of using the Omniflow II prostheses for aortoiliac reconstructions in patients considered to carry a substantial risk of subsequent prosthetic graft infections (prevention group) as well as in patients with actively infected prosthetic vascular grafts (treatment group).

RESULTS

Aorto-bi-iliac (n = 4) and aortobifemoral (n = 12) vascular reconstructions were performed using bifurcated Omniflow II prostheses in nine patients in the prevention group and seven patients in the treatment group. During mean follow-up of 28.6 ± 17.2 months, there was one case of graft infection (6.3%) and graft thrombosis (6.3%) with subsequent successful thrombectomy. Early and late surgical revisions were required in eight (50%) and two (12.6%) patients, respectively. All graft prostheses were patent at last follow-up.

CONCLUSION

Using bifurcated Omniflow II vascular prostheses in patients with or at a high risk of vascular graft infection is advisable, and is associated with acceptable reinfection and patency rates.

FDG PET/CT in abdominal aortic graft infection: A case report and literature review

This case report follows a 47-year-old man who had multiple grafts undergoing FDG PET/CT (positron emission tomography/computed tomography) scan to evaluate for graft infection. Initial CT showed enhancing soft tissue and fluid collection around the graft, and the subsequent FDG PET/CT showed findings concerning for graft infection. This case exemplifies that FDG PET/CT is a synergistic tool in diagnosing aortic graft infections, a rare and often fatal complication of aortic grafts.

Predictive Factors for Aortic Graft Infection: A Case-Control Study

BACKGROUND

Graft infections are one of the most serious complications in vascular surgery, with high mortality rates. Few studies addressed risk factors associated with a higher susceptibility to infection. The aim of this study is to identify perioperative factors associated with aortic graft infections (AGI).

METHODS

We designed a retrospective, case-control study from patients subjected to open aortic repair between 2013 and 2019. Cases of AGI were defined according to the management of aortic graft infection collaboration (MAGIC) criteria and matched to controls without proven infection. Demographics, hospital complications, and laboratory workups were assessed. Predictors of AGI were identified through univariate and multivariate analysis.

RESULTS

Most graft infections occurred in a late period (n = 17; 85%), after a median interval of 13.5 months interquartile range (IQR 1.5-36). Gram-negative bacteria were most frequently isolated in infected grafts, namely Enterobacteriaceae (n = 12). Cases had significantly lower postoperative serum albumin levels (1.9 g/dL vs. 2.4 g/dL; P = 0.002). Alcohol abuse, malignancy, prolonged lengths of stay, wound infection and dehiscence, in-hospital infection, postoperative heart failure or bowel ischemia were significantly correlated to the onset of AGI. In the multivariate analysis, prolonged hospital stays odds ratio (OR 1.05; P = 0.03), malignancy (OR 5.82; P = 0.03) and alcohol abuse (OR 42.41; P = 0.002) maintained a significant association.

CONCLUSIONS

The risk of AGI seems to be higher in patients with concurrent malignancy, alcohol abuse or prolonged hospital stays. Strategies to mitigate this complication in these patients are of utmost importance.

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.

Vascular Graft Infections: An Overview of Novel Treatments Using Nanoparticles and Nanofibers

Vascular disease in elderly patients is a growing health concern, with an estimated prevalence of 15–20% in patients above 70 years old. Current treatment for vascular diseases requires the use of a vascular graft (VG) to revascularize lower or upper extremities, create dialysis access, treat aortic aneurysms, and repair dissection. However, postoperative infection is a major complication associated with the use of these VG, often necessitating several operations to achieve complete or partial graft excision, vascular coverage, and extra-anatomical revascularization. There is also a high risk of morbidity, mortality, and limb loss. Therefore, it is important to develop a method to prevent or reduce the incidence of these infections. Numerous studies have investigated the efficacy of antibiotic- and antiseptic-impregnated grafts. In comparison to these traditional methods of creating antimicrobial grafts, nanotechnology enables researchers to design more efficient VG. Nanofibers and nanoparticles have a greater surface area compared to bulk materials, allowing for more efficient encapsulation of antibiotics and better control over their temporo-spatial release. The disruptive potential of nanofibers and nanoparticles is exceptional, and they could pave the way for a new generation of prosthetic VG. This review aims to discuss how nanotechnology is shaping the future of cardiovascular-related infection management.

Destructive per continuitatem spondylodiscitis after endovascular abdominal or thoracic aneurysm repair (EVAR/TEVAR): rare and untreatable?

INTRODUCTION

Very few publications have previously described spondylodiscitis as a potential complication of endovascular aortic procedures (EVAR/TEVAR). We present to our knowledge the first case series of spondylodiscitis following EVAR/TEVAR based on our data base. Particular focus was laid on the complexity of disease treatment and grave outcome perspectives from a spine surgeon's point of view in this seriously affected patient group.

MATERIALS AND METHODS

A retrospective analysis and chart review was performed for 11 out of 284 consecutive spondylodiscitis patients who underwent EVAR/TEVAR procedure and developed destructive per continuitatem spondylodiscitis.

RESULTS

All 11 patients had single or more level destructive spondylodiscitis adjacent to the thoracic/lumbar stent graft. In mean, four surgeries were performed per patient to treat this rare complication. Six out of eleven patients (55%) died within 6 months of first identification of per continuitatem spondylodiscitis. In four patients due to persisting infection of the graft and recurrence of the abscess formation, a persisting fistula from anterior approach to the skin was applied.

CONCLUSIONS

Destructive per continuitatem spondylodiscitis is a rare and severe complication post-EVAR/TEVAR. Clinical and imaging features of anterior paravertebral disease and anterior vertebral body involvement suggest direct continuous spread of the graft infection to the adjacent vertebral column. The mortality rate of these severe infections is extremely high and treatment with a permanent fistula may be one salvage procedure.

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.

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.

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.

Contemporary Outcomes After Partial Resection of Infected Aortic Grafts

INTRODUCTION

Aortic graft infection remains a considerable clinical challenge, and it is unclear which variables are associated with adverse outcomes among patients undergoing partial resection.

METHODS

A retrospective, multi-institutional study of patients who underwent partial resection of infected aortic grafts from 2002 to 2014 was performed using a standard database. Baseline demographics, comorbidities, operative, and postoperative variables were recorded. The primary outcome was mortality. Descriptive statistics, Kaplan-Meier (KM) survival analysis, and Cox regression analysis were performed.

RESULTS

One hundred fourteen patients at 22 medical centers in 6 countries underwent partial resection of an infected aortic graft. Seventy percent were men with median age 70 years. Ninety-seven percent had a history of open aortic bypass graft: 88 (77%) patients had infected aortobifemoral bypass, 18 (16%) had infected aortobiiliac bypass, and 1 (0.8%) had an infected thoracic graft. Infection was diagnosed at a median 4.3 years post-implant. All patients underwent partial resection followed by either extra-anatomic (47%) or in situ (53%) vascular reconstruction. Median follow-up period was 17 months (IQR 1, 50 months). Thirty-day mortality was 17.5%. The KM-estimated median survival from time of partial resection was 3.6 years. There was no significant survival difference between those undergoing in situ reconstruction or extra-anatomic bypass (P = 0.6). During follow up, 72% of repairs remained patent and 11% of patients underwent major amputation. On univariate Cox regression analysis, Candida infection was associated with increased risk of mortality (HR 2.4; P = 0.01) as well as aortoenteric fistula (HR 1.9, P = 0.03). Resection of a single graft limb only to resection of abdominal (graft main body) infection was associated with decreased risk of mortality (HR 0.57, P = 0.04), as well as those with American Society of Anesthesiologists classification less than 3 (HR 0.35, P = 0.04). Multivariate analysis did not reveal any factors significantly associated with mortality. Persistent early infection was noted in 26% of patients within 30 days postoperatively, and 39% of patients were found to have any post-repair infection during the follow-up period. Two patients (1.8%) were found to have a late reinfection without early persistent postoperative infection. Patients with any post-repair infection were older (67 vs. 60 years, P = 0.01) and less likely to have patent repairs during follow up (59% vs. 32%, P = 0.01). Patients with aortoenteric fistula had a higher rate of any post-repair infection (63% vs. 29%, P < 0.01) CONCLUSION: This large multi-center study suggests that patients who have undergone partial resection of infected aortic grafts may be at high risk of death or post-repair infection, especially older patients with abdominal infection not isolated to a single graft limb, or with Candida infection or aortoenteric fistula. Late reinfection correlated strongly with early persistent postoperative infection, raising concern for occult retained infected graft material.

Communication Training, Adverse Events, and Quality Measures: 2 Retrospective Database Analyses in Washington State Hospitals

OBJECTIVE

Washington State's HealthPact program was launched in 2011 as part of AHRQ's Patient Safety and Medical Liability Reform initiative. HealthPact delivered interdisciplinary communication training to health-care professionals with the goal of enhancing safety. We conducted 2 exploratory, retrospective database analyses to investigate training impact on the frequency of adverse events (AEs) and select quality measures across 3 time frames: pretraining (2009-2011), transition (2012), and posttraining (2013).

METHODS

Using administrative data from Washington State's Comprehensive Hospital Abstract Reporting System (CHARS) and clinical registry data from the Surgical Care and Outcomes Assessment Program (SCOAP), we compared proportions of AEs and quality measures between HealthPact (n = 4) and non-HealthPact (n = 93-CHARS; n = 48-SCOAP) participating hospitals. Risk ratios enabled comparisons between the 2 groups. Multivariable logistic regression enabled investigation of the association between training and the frequency of AEs.

RESULTS

Approximately 9.4% (CHARS) and 7.7% (SCOAP) of unique patients experienced 1 AE or greater. In CHARS, the odds of a patient experiencing an AE in a HealthPact hospital were initially (pretraining) higher than in a non-HealthPact hospital (odds ratio [OR], 1.13; 95% confidence interval [CI], 1.10-1.17), lower in transition (OR, 0.80; 95% CI, 0.76-0.83) and posttraining (OR, 0.72; 95% CI, 0.69-0.75) periods. In SCOAP, ORs were consistently lower in HealthPact hospitals: pretraining (OR, 0.87; 95% CI, 0.80-0.95), transition (OR, 0.75; 95% CI, 0.70-0.81), and posttraining (OR, 0.63; 95% CI, 0.58-0.68). The proportion of at-risk patients that experienced each individual AE was low (<1%) throughout. Adherence to quality measures was high.

CONCLUSIONS

Interprofessional communication training is an area of intense activity nationwide. A broad-based training initiative may play a role in mitigating AEs.

Outpatient parenteral antimicrobial therapy (OPAT) for aortic vascular graft infection; a five-year retrospective evaluation

OBJECTIVES

An estimated 1% of endovascular aneurysm repair (EVAR) devices become infected, carrying a high mortality rate. Surgical explantation is recommended and prognosis is guarded. This retrospective cohort analysis focuses on the role of outpatient parenteral antimicrobial therapy (OPAT) in the management of aortic vascular graft infections following EVAR.

METHODS

Patients who received OPAT for aortic graft infections (AGI) following EVAR from 2014 to 2018 inclusive were identified using the OPAT database. Clinical, microbiological and radiological data were collected. Survivors were followed up for a median of 36 months (range 25-60) after first presentation with infection. Outcomes were assessed.

RESULTS

Eleven cases with 20 OPAT episodes were identified: 10/11 male, median age 76 (IQR 71-81). Median time to presentation was 7 months (range 0-81 months) after EVAR. OPAT lead to a 55% reduction in length of hospital stay. One patient had graft explantation; four others had temporising measures. Eight of 11 were alive a median of 36 months after presentation with infection, having had a median of 2 re-treatments on OPAT (range 1-3). Seven of the eight survivors were on continuous suppressive oral antimicrobials; three were also intermittently on intravenous antibiotics for flares of infection. Patient/ infection outcomes were cure (1/11), improved (7/11), failure (3/11).

CONCLUSION

AGI following EVAR usually presents in the first year after graft deployment. OPAT has an important peri-operative role in patients suitable for curative surgery. OPAT followed by oral suppressive antimicrobial therapy can be a feasible long-term treatment for non-curative management of AGI. Survival in our cohort was longer than expected, and OPAT was feasible despite the complexity of these infections. OPAT can avoid multiple and lengthy hospital admissions and maximise time at home and quality of life in this cohort with life-limiting infection.

Infections of the aorta

Infection of the aorta continues to be a clinical challenge with high morbidity and mortality. The incidence varies between 0.6 and 2.6%. There has been a steady increase in graft infections, especially endograft infections, due to increased procedures (0.2 to 5%). Staphylococcus species remains the most common organism; however, gram-negative and rare causative agents are also reported. The clinical presentation can be very diverse and a high degree of suspicion is necessary to diagnose them. Sometimes, they may present as an emergency with rupture or fistulation. Diagnosis is based on a triad of clinical features, microbial cultures and imaging. Culture-specific antibiotics are mandatory during the entire course, but seldom cure alone. Surgical management remains the standard of care and involves an integrated approach involving debridement, reconstruction and use of adjuncts. Various aortic substitutes have been described with advantages and limitations. Pericardial tube grafts have emerged as a good option. Endo-vascular options are practiced mostly as a bridge to definitive surgery. A small role for conservative management is described. Aortic fistulation to the gut and airway carries a very high mortality. There are no large series in the literature to define guideline-directed treatment and most often it is a customized solution. The 30-day mortality remains close to 30%. Outcomes depend on multiple factors including patient's age, the timing of presentation, diagnosis, causative organism, host status and the treatment strategy adopted.

Short and Mid Term Outcomes of Cryopreserved Abdominal Aortic Allografts Used as a Substitute for Infected Prosthetic Grafts in 200 Patients

OBJECTIVE

To investigate the use of cryopreserved arterial allografts (CAA) as a substitute for infected infrarenal aortic prostheses, and its outcomes.

METHODS

A single centre retrospective study of consecutive patients receiving an abdominal aortic CAA after removal of an infected graft was conducted between January 1997 and December 2013. The primary outcome was the rate of allograft related revision surgery. Secondary outcomes were the 30 day mortality rate, survival, primary patency, limb salvage, and infection recurrence. Allograft ruptures secondary to infection and risk factors for allograft failure were also investigated.

RESULTS

Two hundred patients (mean age 64.2 ± 9.4 years) were included. In 56 (28%) cases, infection was related to an enteric fistula. The mean follow up duration was 4.1 years. The 30 day mortality rate was 11%. Early revision surgery was needed in 59 patients (29.5%). Among them, 15 (7.5%) were allograft related and led to the death of three patients (1.5%), corresponding to a 7.5% 30 day allograft related revision surgery rate. During the first six months, 17 (8.5%) patients experienced 21 events with complete or partial rupture (pseudo-aneurysm) of the allograft responsible for five (2.5%) deaths, corresponding to a re-infection rate of 8.5%. The multivariable analysis showed that diabetes and pseudo-aneurysm of the native aorta on presentation were predictive factors for short term allograft rupture. After six months, 25 (12.5%) patients experienced long term allograft complications (rupture, n = 2, 1%; pseudo-aneurysm, n = 6, 3%; aneurysm, n = 2, 1%; thrombosis, n = 11, 5.5%; stenosis, n = 4, 2%;) requiring revision surgery resulting in one death. The five year rates of survival, allograft related revision surgery, limb salvage, primary patency, and infection recurrence were 56%, 30%, 89%, 80%, and 12%, respectively.

CONCLUSION

CAAs provide acceptable results to treat aortic graft infection with few early graft related fatal complications. Long term allograft related complications are quite common but are associated with low mortality and amputation rates.

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

OBJECTIVE

Vascular graft infection (VGI) remains an important complication with a high mortality and morbidity rate. Currently, studies focusing on the role of vascular graft coatings in the prevention of VGI are scarce. Therefore, the aims of this study were to survey and summarise key features of pre-clinical in vivo models that have been used to investigate coating strategies to prevent VGI and to set up an ideal model that can be used in future preclinical research.

DATA SOURCES

A systematic review was conducted in accordance with the Preferred reporting items for Systematic Reviews and Meta-Analysis guidelines. A comprehensive search was performed in MEDLINE (PubMed), Embase, and Web of Science.

REVIEW METHODS

For each database, a specific search strategy was developed. Quality was assessed with the Toxicological data Reliability Assessment Tool (ToxRTool). The type of animal model, graft, coating, and pathogen were summarised. The outcome assessment in each study was evaluated.

RESULTS

In total, 4 667 studies were identified, of which 94 papers focusing on in vivo testing were included. Staphylococcus aureus was the organism most used (n = 65; 67.7%). Most of the graft types were polyester grafts. Rifampicin was the most frequently used antibiotic coating (n = 43, 48.3%). In the outcome assessment, most studies mentioned colony forming unit count (n = 88; 91.7%) and clinical outcome (n = 72; 75%). According to the ToxRTool, 21 (22.3%, n = 21/94) studies were considered to be not reliable.

CONCLUSION

Currently published in vivo models are very miscellaneous. More attention should be paid to the methodology of these pre-clinical reports when transferring novel graft coatings into clinical practice. Variables used in pre-clinical reports (bacterial strain, duration of activity coating) do not correspond well to current clinical studies. Based on the results of this review, a proposal for a complete and comprehensive set up for pre-clinical invivo testing of anti-infectious properties of vascular graft coatings was defined.

[Outcomes of endoprosthetic repair of abdominal aortic aneurysm]

AIM

The study was aimed at assessing efficacy and safety of endovascular treatment of abdominal aortic aneurysms based on 11-year experience with implantation of stent grafts.

PATIENTS AND METHODS

We retrospectively analysed outcomes of treatment of 242 patients with abdominal aortic aneurysm during the period from 2008 to 2019. Of these, 210 (86.78%) were males, mean age 69.32±7.36 years. Diagnosis was made using colour duplex scanning and contrast-enhanced multislice spiral computed tomography, with implanting the following stent grafts: Ella - 44, Ovation Prime - 33, Anaconda - 13, Endurand - 77, Aortix - 2, Zenith - 33, Seal - 39, with one endoprosthesis placement failed. Assessing safety of the operation, we took into consideration lethality due to aortic rupture/thrombosis. Efficacy was taken to mean technical success of the operation (implantation of all components of the endograft without switch to open surgery), the number of reoperations.

RESULTS

Technical success of the operation was achieved in 98.35% of cases. In 1 case due to pronounced arterial calcification for technical reasons we failed to position the stent graft and in another case - the contralateral leg of the Ella prosthesis. The early postoperative period revealed: type A1 endoleak - 3.7%, type IB - 4.13%, type IIA - 6.6%, type IIB - 4.54%, type III - 0.83%, type IV - 0.83%. Repeat operations were performed in 20 (8.2%) patients within 30 days after the intervention and in 32 (13.22%) in the remote period. In the early postoperative period two conversions were performed: 1) iliorenal bypass grafting for restoration of blood flow through the renal artery occluded by endoprosthesis wall; 2) evacuation of retroperitoneal haematoma due to rupture of the common femoral artery. Lethality during the whole period of follow up amounted to 32 (13.22%) cases. Of these, due to aortic complications 4.54% (n=11) and due to accompanying pathology 8.67% (n=21). A direct correlation was revealed between the aortic diameter and duration of the operation which in turn increases the risk of complications requiring re-operation or resulting in a lethal outcome (RR - 1; 95% CD 1- 1; p=0.026).

CONCLUSION

Our experience showed high safety and efficacy of stent graft implantation in treatment of patients with abdominal aortic aneurysms and high surgical risk.

Microbial evolution of vascular graft infections in a tertiary hospital based on positive graft cultures

BACKGROUND

Vascular graft infections are a serious complication in vascular surgery. Correct antibiotic therapy targeted to the most likely infecting species is essential to treat these patients, although the bacterial epidemiology and pathogenesis are still not completely understood. We analyzed the behavior of vascular graft infections and the microbiologic patterns of resistance.

METHODS

A 10-year (2008-2018), single-center, retrospective cohort study was performed of all patients admitted with vascular graft infection identified by positive direct graft cultures. An extensive microbiologic study was performed to analyze the bacterial strains, antibiotic resistance and sensitivity, and prevalence stratified by the year.

RESULTS

A total of 72 vascular graft infections with positive graft cultures occurring in 65 patients were found. Their mean age was 67 ± 9.6 years, and 85% were men. Infection-related mortality was 11%. Of the 65 patients, 14 had undergone aortobifemoral bypass, 13 axillofemoral bypass, 5 femorofemoral bypass, 27 femoropopliteal bypass, and 4 femoral endarterectomy with synthetic patch angioplasty. The median interval from the index procedure to infection was longer for intracavitary than for extracavitary grafts (P = .011). Of the 72 infections, 48 were monomicrobial and 24 were polymicrobial. Gram-negative bacteria were predominantly identified in intracavitary graft infections (54%). In contrast, gram-positive bacteria were most frequent in the extracavitary graft group (58%). Multidrug-resistant bacterial species occurred more frequently in early graft infections (P = .002). Throughout the study duration, an overall decrease in gram-positive infections and an increase in gram-negative infections was observed, especially in extensively drug-resistant strains. A similar progression was found in all nosocomial infections.

CONCLUSIONS

The present study has shown that vascular graft infection microbiology changed in accordance with graft location and interval to infection from revascularization surgery and had also evolved over the study period with patterns similar to those for all nosocomial infections. This highlights the importance of studying the specific microbiology of each healthcare center and its relationship to vascular graft infections to achieve the best treatment possible.

Mid-Term Outcome of Infected Abdominal Aortic Stent Graft Dismantlement with Reconstruction of Bilateral Axillofemoral Bypass

Background: Abdominal aortic stent graft infection (AAGI) is a severe complication. The optimal management of AAGI remains unclear. This study provides updated results of bilateral axillofemoral bypasses (AFBs) for patients with AAGI. Patients and Methods: In total, 31 patients (25 men; mean age, 67.1 years) with AAGI treated using AFB between January 2006 and April 2020 were included. Overall, the mean follow-up duration was 24 months (range, 1-72). In the 23 patients who survived the post-operative period, the mean follow-up duration was 32 months (range, 12-72). Results: Thirty-day and in-hospital mortality rates was 16% and 26%, respectively. The 12-month primary and secondary patency rates for the AFB graft were both 91%. In total, seven (30%) patients received re-interventions such as thrombectomy and balloon angioplasty. No amputation was required during follow-up. Culture results were positive in 87% of pre-operative cultures and 84% of intra-operative cultures. Staphylococcus aureus was the most prevalent pathogen, with four cases of methicillin-resistant Staphylococcus aureus and one each of vancomycin-resistant enterococci, carbapenem-resistant Klebsiella pneumoniae, and carbapenem-resistant Enterobacteriaceae. In-hospital mortality rate was 57% in patients with drug-resistant pathogens. Conclusions: Reconstruction with bilateral AFB and stent graft removal in patients with AAGI is a feasible treatment modality and provided an acceptable patency rate and low amputation rate. Additional studies investigating long-term results and the optimal treatment of AAGI are required.

Update on graft infections in thoracoabdominal aortic aneurysm surgery

The incidence of an aortic graft infection following the repair of thoracoabdominal aortic aneurysm, is a rare yet insidious complication which requires prompt recognition and management. The decision-making framework for management encompasses the choice or antimicrobial therapy alone versus pursuing surgical intervention, which can then also lead to considering the potential for allografts. The current literature on the matter is heavily burdened by limitations of the reported retrospective experiences consisting of small patient cohorts. Studies have reported the favored approach of surgical intervention, although statistical significance is not reached. There is a clear recognized impact that the event surrounding the initial repair has on the occurrence of graft infection itself; with emergency repairs, and incidence of nosocomial infection being associated with higher rates of graft infection. We must consider the influencers of this ominous complications, which go back to the perioperative events itself, whether the initial intervention was elective or an emergency, the impact of nosocomial infections, the choice of open versus endovascular for initial repair. Only with the appropriate management strategy that encompasses all these factors, will allow the best treatment to be provided for patients. A sound understanding and appreciation for the aforementioned can allow the stratification of the risk associated with the occurrence of an aortic graft infection, leading to surveillance opportunities to provide the crucial ability to rapidly recognize this complication.

A case report of a unique aorto-bifemoral graft infection and its treatment

In this study, we report a unique case of aorto-bifemoral graft infection, which developed in a 47-year-old male patient after endovascular aortic aneurysmal repair (EVAR) and extra anatomic axillo-femoral bypass. The patient had previously been treated by EVAR for an infrarenal abdominal aortic aneurysm. Earlier, the EVAR was blocked by a thrombosis and treated with an extra-anatomic axillo femoral bypass, which then became occluded. The patient was then treated with an aorto-bifemoral bypass using a Dacron Y graft. A few months later, he was referred to our cardiovascular center with high body temperature, weight loss, inability to stand and walk, and very serious sepsis. A computed abdominal tomography scan revealed that a part of the graft proximal to the bifurcation had totally eroded into the proximal jejunum. We treated this patient with multiple surgeries, antibiotic administrations and hypochlorous acid irrigation without graft excision, which carries a high morbidity and mortality risks.

Hybrid Repair Combined with Fresh Arterial Allograft Extra-Anatomical Reconstruction: The Treatment of Infrarenal Abdominal Aneurysm above an Aortobifemoral Bypass Complicated by an Infected Pseudoaneurysm in the Left Groin

Introduction

A 72-year-old male patient was admitted into our centre with large infected pseudoaneurysm (PSA) in the left groin. The patient underwent a CT angiography (CTA) that confirmed a large partly thrombosed 6.5 × 5.5 cm PSA in the left groin arising from the distal anastomosis of the aortobifemoral bypass (ABF). Furthermore, the CTA revealed 11 cm juxtarenal abdominal aortic aneurysm (JAAA) from which the proximal anastomosis of the ABF was arising.

Method

Aorto-uni-iliac stent graft Cook was placed from the right groin trough native severely stenotic right iliac arteries with proximal landing zone below the renal arteries, excluding the JAAA and the ABF. The distal landing zone was in the common iliac artery maintaining patent right internal iliac artery. Afterwards, a femoro-femoral crossover bypass from right to left was performed using a fresh arterial allograft. Postprocedurally, the hospital stay was uneventful. The left groin PSA cultures came positive for Staphylococcus epidermidis and Corynebacterium tuberculostearicum, both sensitive to vancomycin and rifampicin.

Result

The patient underwent intravenous ATB treatment with vancomycin for two weeks, followed by four weeks of oral rifampicin. The patient was discharged on the 20^th postoperative days.

Conclusion

Hybrid repair combining aortic stent graft and extra-anatomical bypass in the treatment of infected distal parts of an aortofemoral bypass is an acceptable treatment modality.

Aortic Prosthesis-Associated MDR Pseudomonas Infections as a Diagnostic and Therapeutic Challenge

Endovascular prostheses are used to treat life-threatening conditions such as ruptured aortic aneurysms. Prosthetic infection cause significant morbidity and mortality, posing important diagnostic and therapeutic challenges. It is particularly difficult to diagnose and, in the era of multidrug resistance (MDR), these type of infections may become even more difficult to treat. Herein, we reported a case of a secondary prosthetic endovascular infection following repeated bacteremia episodes from a urinary source. This case illustrates an MDR Pseudomonas aeruginosa aortic infection that was difficult to diagnose with no oral antibiotic treatment options.

Abdominal aortic aneurysms part two: Surgical management, postoperative complications and surveillance

Large, symptomatic and ruptured abdominal aortic aneurysms are usually treated surgically if patients are deemed fit enough. This may be achieved through endovascular or open surgical repair. The type of treatment that a patient receives is dependant on many factors, such as the rupture status of the aneurysm. Each approach is also associated with different risks and postoperative complications. Multiple guidelines exist to inform the surgical management of abdominal aortic aneurysms. This literature review combines these recommendations and explores the evidence upon which they are based. In addition, it highlights the key perioperative considerations that need to be considered in cases of unruptured and ruptured abdominal aortic aneurysms.

Efficacy of antiseptic impregnation of aortic endografts with rifampicin compared to silver against in vitro contamination with four bacteria that frequently cause vascular graft infections

OBJECTIVE

This in vitro study investigates the antimicrobial efficacy of impregnation of commercially available aortic endografts (EG) with rifampicin (RIF) and nanocolloidal silver.

METHODS

Endografts were flushed with 50 mL of RIF 600 mg, 70 mL of a silver-based aqueous solution (AG), or 50 mL of phosphate-buffered saline (PBS) over 15 minutes. Endografts were then retrieved from the sheath and cut in 1 × 1 cm sized graft units (n = 80 of each impregnation), which were then incubated for 1 hour separately with inoculates containing 10⁶ or 10³ bacteria per milliliter (bact/mL) of each of the following bacteria: Staphylococcus epidermidis, Escherichia coli, multisensitive Staphylococcus aureus, and Pseudomonas aeruginosa. After sonication of the graft units, bacterial counts were measured by plating out twice the sonication solution on Mueller-Hinton plates.

RESULTS

RIF showed a statistically significant decrease of colony forming units per milliliter for all four bacterial strains in both concentrations compared with PBS and AG, except for 10³ bact/mL of E coli. AG showed a significant decrease of colony forming units per milliliter compared with PBS only for 10⁶ bact/mL of E coli and was statistically significantly inferior to RIF for all four bacterial strains in both concentrations with the exception of E coli at a concentration of 10³ bact/mL.

CONCLUSIONS

This in vitro study demonstrated infectivity resistance of aortic EG after flushing with RIF. Moreover, the feasibility of flushing aortic EG with a new silver-based agent could be demonstrated, but without statistically significant antimicrobial efficacy compared with native EG.

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.

Do Surgical Site Infections in Open Aortoiliac Surgery Differ Between Occlusive and Aneurysmal Arterial Disease?

Background:

Surgical site infections (SSI) are frequently seen after aortoiliac vascular surgery (2%-14%). Deep SSIs are associated with graft infection, sepsis, and mortality. This study evaluates the difference in incidence and nature of SSI following open aortoiliac surgery for aneurysmal disease compared to occlusive arterial disease.

Methods:

A retrospective cohort study was conducted, including all consecutive patients who underwent open aortoiliac vascular surgery between January 2005 and December 2016 in the Amphia Hospital, Breda, the Netherlands. Patients were grouped by disease type, either aneurysmal or occlusive arterial disease. Data were gathered, including patient characteristics, potential risk factors, and development of SSI. Surgical site infections were defined in accordance with the criteria of the Centers for Disease Control.

Results:

Between January 2005 and December 2016, a total of 756 patients underwent open aortoiliac surgery of which 517 had aortoiliac aneurysms and 225 had aortoiliac occlusive disease. The group with occlusive disease was younger, predominantly male, and had more smokers. After exclusion of 228 patients undergoing acute surgery, the SSI rate after elective surgery was 6.2%, with 10 of 301 SSIs in the aneurysmal group (3.0%) and 22 of 213 SSIs in the group with occlusive disease (10.3%, P < .001). Also, infection-related readmission and reintervention were higher after occlusive surgery, 6.6% versus 0.9% ( P < .001) and 4.2% versus 0.9% ( P = .003), respectively. Staphylococcus aureus was found as the most common pathogen, causing 64% of SSI in occlusive disease versus 10% in aneurysmal disease ( P = .005). Logistic regression showed occlusive arterial disease and chronic renal disease were associated with SSI.

Conclusion:

Our study presents evidence for a higher rate of SSI in patients with aortoiliac occlusive disease compared to aortoiliac aneurysmal disease, in part due to inherent use of inguinal incision in patients with occlusive disease. All precautions to prevent SSI should be taken in patients undergoing vascular surgery for arterial occlusive disease.

Physiological Appearance of Hybrid FDG-Positron Emission Tomography/Computed Tomography Imaging Following Uncomplicated Endovascular Aneurysm Sealing Using the Nellix Endoprosthesis

Purpose: To investigate the physiological uptake of hybrid fluorine-18-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) before and after an uncomplicated endovascular aneurysm sealing (EVAS) procedure as a possible tool to diagnose EVAS graft infection and differentiate from postimplantation syndrome. Materials and Methods: Eight consecutive male patients (median age 78 years) scheduled for elective EVAS were included in the prospective study (ClinicalTrials.gov identifier NCT02349100). FDG-PET/CT scans were performed in all patients before the procedure and 6 weeks after EVAS. The abdominal aorta was analyzed in 4 regions: suprarenal, infrarenal neck, aneurysm sac, and iliac. The following parameters were obtained for each region: standard uptake value (SUV), tissue to background ratio (TBR), and visual examination of FDG uptake to ascertain its distribution. Demographic data were obtained from medical files and scored based on reporting standards. Results: Visual examination showed no difference between pre- and postprocedure FDG uptake, which was homogenous. In the suprarenal region no significant pre- and postprocedure differences were observed for the SUV and TBR parameters. The infrarenal neck region showed a significant decrease in the SUV and no significant decrease in the TBR. The aneurysm sac and iliac regions both showed a significant decrease in SUV and TBR between the pre- and postprocedure scans. Conclusion: Physiological FDG uptake after EVAS was stable or decreased with regard to the preprocedure measurements. Future research is needed to assess the applicability and cutoff values of FDG-PET/CT scanning to detect endograft infection after EVAS.

In situ bypass and extra-anatomic bypass procedures result in similar survival in patients with secondary aortoenteric fistulas

OBJECTIVE

The optimal revascularization modality in secondary aortoenteric fistula (SAEF) remains unclear in the literature. The purpose of this investigation was to determine the revascularization approach associated with the lowest morbidity and mortality using real-world data in patients with SAEF.

METHODS

A retrospective, multi-institutional study of SAEF from 2002 to 2014 was performed using a standardized database. Baseline demographics, comorbidities, and operative and postoperative variables were recorded. The primary outcome was long-term mortality. Descriptive statistics, Kaplan-Meier survival analysis, and univariate and multivariate analyses were performed.

RESULTS

During the study period, 182 patients at 34 institutions from 11 countries presented with SAEF (median age, 72 years; 79% male). The initial aortic procedures that resulted in SAEF were 138 surgical grafts (76%) and 42 endografts (23%), with 2 unknown; 102 of the SAEFs (56%) underwent complete excision of infected aortic graft material, followed by in situ (in-line) bypass (ISB), including antibiotic-soaked prosthetic graft (53), autogenous femoral vein (neoaortoiliac surgery; 17), cryopreserved allograft (28), and untreated prosthetic grafts (4). There were 80 patients (44%) who underwent extra-anatomic bypass (EAB) with infected graft excision. Overall median Kaplan-Meier estimated survival was 319 days (interquartile range, 20-2410 days). Stratified by EAB vs ISB, there was no significant difference in Kaplan-Meier estimated survival (P = .82). In comparing EAB vs ISB, EAB patients were older (74 vs 70 years; P = .01), had less operative hemorrhage (1200 mL vs 2000 mL; P = .04), were more likely to initiate dialysis within 30 days postoperatively (15% vs 5%; P = .02), and were less likely to experience aorta-related hemorrhage within 30 days postoperatively (3% aortic stump dehiscence vs 11% anastomotic rupture; P = .03). There were otherwise no significant differences in presentation, comorbidities, and intraoperative or postoperative variables. Multivariable Cox regression showed that the duration of antibiotic use (hazard ratio, 0.92; 95% confidence interval, 0.86-0.98; P = .01) and rifampin use at time of discharge (hazard ratio, 0.20; 95% confidence interval, 0.05-0.86; P = .03) independently decreased mortality.

CONCLUSIONS

These data suggest that ISB does not offer a survival advantage compared with EAB and does not decrease the risk of postoperative aorta-related hemorrhage. After repair, <50% of SAEF patients survive 10 months. Each week of antibiotic use decreases mortality by 8%. Further study with risk modeling is imperative for this population.