Vascular Graft Infection Research Articles

Leg Ulcer and Venous Symptoms Related to Lower Extremity Arteriovenous Access for Hemodialysis: A Retrospective Review with Emphasis on Wound Complications.

Lower extremity arteriovenous (AV) access serves as a crucial alternative for hemodialysis when upper extremity options are no longer viable. While there are numerous reports on functional patency, limited information exists regarding complications related to venous insufficiency and postoperative quality of life. This study aims to assess the actual incidence of such complications and provide evidence-based insights for clinical decision-making. We retrospectively analyzed 121 end-stage renal disease patients who underwent lower extremity AV access at Maharaj Nakorn Chiang Mai Hospital from 2006 to 2023. Among them, 105 patients (86.8%) had lower extremity AV grafts, while 16 patients (13.2%) had lower extremity AVF. Primary and secondary patency rate were 69.4% and 81.8% at one year, respectively. The mortality probability was 50.4% with a mean follow-up of 58 months. Mortality predictors included age (P = .001), aspirin use (P = .022) and statin use (P = .005). Primary failure occurred in 8 patients (6.6%) and vascular graft infection is the primary cause. There were no occurrences of venous leg ulcers developed, suggesting that the risk of this complication may be lower than previously thought in the short to medium term. However, 13.3% of patients experienced leg swelling and 21.7% had hyperpigmentation. The mean revised venous clinical severity score was 1.22 and the average EQ-5D-5L quality of life score was 0.99. Our findings suggest that the risk of venous leg ulcers in patients with lower extremity AV access may be lower than previously thought, at least in the short to medium term. This should encourage surgeons to consider this technique when upper extremity options are exhausted, while maintaining vigilance for early signs of venous insufficiency. Continued research into the detrimental effects of the hyper-dynamic blood flow rate on AV access and preventive strategies will enhance the benefit of lower extremity AV access in the future.

Candida associated infra-inguinal prosthetic vascular graft infection: A case report

Prosthetic vascular grafts (PVG) are artificial vascular materials used for revascularization in the treatment of vascular diseases. Due to increase in life expectancy, the number of individuals requiring PVGs is increasing and encountering the PVGI is also more frequent. We presented an interesting case operated because of infected graft in which Candida albicans grew. The patient had been operated twice for peripheral artery disease in another hospital before. We performed femoro-popliteal bypass by using great saphenous vein after removal of infected graft. In peripheric bypass surgery performed with PTFE (polytetrafluoroethylene) graft, growth of Candida albicans in graft material is a rare condition and this situation has a high mortality rate. In the patients with comorbidities and who will undergo redo-surgery, excessive care should be given in terms of graft infections.

Vascular Graft Impregnation with a Fosfomycin/Oritavancin Combination to Prevent Early Infection.

Background/Objectives: Vascular graft infections (VGIs) represent a life-threatening complication, occurring in 0.2-6% of patients following aortic prosthetic placements. Historically, the primary focus for reducing VGIs has been on prevention. Currently, antimicrobial grafts are not available on the market. This study aimed to evaluate the efficacy of combining two antibiotics, fosfomycin and oritavancin, impregnated into the commercially available GelweaveTM vascular graft as a prophylactic alternative against the most commonly implicated bacteria responsible for VGI. Methods: The antimicrobial activity of fosfomycin and oritavancin was assessed using the broth microdilution method, and a synergistic effect was demonstrated using the checkerboard assay against Staphylococcus epidermidis, methicillin-resistant Staphylococcus aureus, and vancomycin-resistant Enterococcus faecium. The antibiotics were impregnated into the commercial vascular graft through immersion, and the antimicrobial efficacy of the fosfomycin/oritavancin-impregnated graft was assessed over a period of 7 days. Results: Eradication of all microorganisms tested was achieved using impregnation solutions with concentrations of 40 mg/mL of fosfomycin and 256 µg/mL of oritavancin. Conclusions: Impregnation with the combination of fosfomycin/oritavancin proved to be a promising approach to prevent VGIs. Vascular grafts with impregnated antibiotics are not yet available on the market, and this work represents an important step toward the development of a new class of antimicrobial vascular grafts.

Rifampin in device-related infections: Assessing the modern evidence.

In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time. Rifampin is commonly used to treat device-related infections (DRIs) due to its activity against biofilms, despite a history of limited clinical evidence to support its use. Evidence published since 2011 regarding rifampin use for DRIs is reviewed to describe the contemporary findings and ongoing considerations for rifampin use in these infections. A literature review was performed by searching PubMed and Google Scholar to identify relevant studies evaluating systemic rifampin use for the treatment of DRIs published from 2011 to 2023. References of identified studies were also screened for additional pertinent studies. Sixty-eight studies were identified, and 48 met the inclusion criteria. Rifampin efficacy was evaluated as both a primary outcome for cardiac device infections (n = 3) and prosthetic joint infections (n = 21) and as a nonprimary outcome (n = 24). Overall, the studies were primarily retrospective (n = 36) and small, with sample sizes ranging from 14 to 842 patients, and varied greatly with respect to prosthesis site, surgical intervention, pathogen, infection time frame, and antibiotic combination and duration. Efficacy outcome results varied greatly, with statistically significant evidence for the efficacy of rifampin combination in DRIs limited to a single study of prosthetic vascular graft infections and 13 studies of prosthetic joint infections. The modern literature provides conflicting results regarding the benefit and lack of benefit with rifampin combination therapy in DRIs. Additional, robust research is imperative to solidify the ongoing role of rifampin in DRIs.

A Case of Colorectal Cancer Detected by Vascular Graft Infection Caused by <i>Listeria Monocytogenes</i>

A Case of Colorectal Cancer Detected by Vascular Graft Infection Caused by <i>Listeria Monocytogenes</i>

Management of thoracic aortic graft infections with combined omental and bilateral pectoralis major flaps

BackgroundAortic vascular graft/endograft infection (VGEI) has historically been managed through graft removal and re-replacement, but new approaches suggest vascularized tissue transfer is an effective adjunctive treatment. Here we describe our experience with treating thoracic aortic vascular graft infection with combined omental and bilateral pectoralis major myocutaneous (PMM) advancement flaps. MethodsAll patients undergoing combined flap closure by the senior author at a high-acuity cardiac surgery center from 1995-2023 were reviewed. Patients with clinical and radiographic signs of thoracic aortic vascular graft infection were included. ResultsComplete data were available for 598 patients with sternal and mediastinal wounds. Combined PMM and omental flaps were mobilized in 11 thoracic aortic vascular graft infection patients. Indications for flap management included culture-positive infection (8/11; 72.7%), dehiscence (5/11; 45.5%), drainage (7/11; 63.6%), and inability to close the sternotomy due to hemodynamic instability (5/11; 45.5%). During chest exploration, 6/11 (54.5%) underwent complete removal of the infected graft, compared to 5/11 (45.5%) who underwent graft-preserving washout and debridement. Immediate flap closure was performed in 6/11 (54.5%). Post-op complications included dehiscence (2/11; 18.2%), seroma (1/11; 9.1%), hematoma (1/11, 9.1%), abdominal hernia (1/11; 9.1%), and recurrent infection (1/11; 9.1%). One patient (9.1%) died within 30 days of sternal reconstruction from mitral valve failure tachyarrhythmia. None has undergone reoperation for flap-related complications. ConclusionsDespite significant comorbidities, low postoperative morbidity and mortality indicate that combined omental and pectoralis major flaps are a safe and effective adjunctive treatment to the antimicrobial and surgical management of select thoracic aortic vascular graft infections.

Artificial Neutrophils Against Vascular Graft Infection.

Efficient neutrophil migration to infection sites plays a vital role in the body's defense against bacterial infections and natural immune responses. Neutrophils have a short lifespan and cannot be mass-cultured in vitro. Therefore, developing more stable artificial neutrophils (AN) in a controllable manner has become a research focus. However, existing AN lack chemotaxis, which is the ability to migrate toward high-signal-concentration positions in a dynamic blood- flow environment. Supplying AN with chemotaxis is key to designing AN that are more similar to natural neutrophils in terms of morphology and function. In this study, micrometer-sized, spherical, biocompatible AN are developed. These AN consist of zeolitic imidazolate framework-8 nanoparticles encapsulating two enzymes, coacervate droplet frameworks, and outer phospholipid bilayers carrying enzymes. The AN exhibit responsiveness to elevated hydrogen peroxide levels at inflammation sites, actively chemotaxing toward these sites along concentration gradients. They also demonstrate effective combat against Staphylococcus aureus infections. The capabilities of the AN are further validated through in vitro experiments and in vivo evaluations using vascular graft infection models. This study replicates natural neutrophils in terms of chemical composition, functionality, and physiological impact. It introduces new ideas for advancing the development of advanced artificial cells.

Enterococcus-related vascular graft infection: A case series

ObjectivesWe aimed to assess the frequency, management, and burden of enterococcal-related vascular graft infection. Patients and methodsFrom 2008 to 2021, data regarding all episodes of vascular graft infections initially managed or secondarily referred to our referral center were prospectively collected. We described the history and management of the infection, depending on the type of prosthesis used. ResultsThe frequency of enterococcal-related vascular graft infections was 29/249 (12 %). Most of them were early infections (22/29, 76 %). Infections were polymicrobial (26/29, 90 %), mostly associated with Enterobacterales. Among patients with positive blood cultures, 7/8 (88 %) involved enterococci. Patients with enterococcal-related vascular graft infections were mainly (22/29, 76 %) treated with an association of antibiotics. Mortality and relapse occurred in 28 % and 7 % respectively of the cases. ConclusionsEnterococcal-related vascular graft infections occurred in patients with comorbidities, during the early period following surgery and were more frequent in cases of intra-cavitary prosthesis. Their potential virulence needs to be considered, especially in polymicrobial infections.

Antibiotic Delivery via a Chitosan-Based Nanofibrous Coating of Prosthetic Grafts for Treatment of Vascular Graft Infections

Antibiotic Delivery via a Chitosan-Based Nanofibrous Coating of Prosthetic Grafts for Treatment of Vascular Graft Infections

Phage Therapy for Cardiac Implantable Electronic Devices and Vascular Grafts: A Targeted Literature Review.

Infections of cardiac implantable electronic devices (CIEDs) and vascular grafts are some of the most dreaded complications of these otherwise life-saving devices. Many of these infections are not responsive to conventional treatment, such as systemic antibiotics and surgical irrigation and debridement. Therefore, innovative strategies to prevent and manage these conditions are warranted. Among these, there is an increasing interest in phages as a therapeutical option. In this review, we aim to collect the available evidence for the clinical application of phage therapy for CIED and vascular graft infections through literature research. We found 17 studies for a total of 34 patients. Most of the indications were left ventricular assist device (LVAD) (n = 20) and vascular graft infections (n = 7). The bacteria most often encountered were Staphylococcus aureus (n = 18) and Pseudomonas aeruginosa (n = 16). Clinical improvements were observed in 21/34 (61.8%) patients, with microbiological eradication in 18/21 (85.7%) of them. In eight cases, an adverse event related to phage therapy was reported. Phage therapy is a promising option for difficult-to-treat CIED and vascular graft infections by means of an individualized approach. Clinical trials and expanded access programs for compassionate use are needed to further unveil the role of phage therapy in clinical application.

PROSTHETIC GRAFT INFECTION: WHEN ECHOCARDIOGRAPHY IS NOT ENOUGH!

Abstract A 68–year–old Caucasian male, post–Bentall procedure with a bioprosthetic valve following extensive aortic dissection involving the ascending aorta and aortic arch, presented to the Emergency Department with persistent fever for over a month. During his hospitalization, he experienced ventricular fibrillation in the setting of hypokalemia, successfully managed with Advanced Cardiovascular Life Support (ACLS) and DC shock, leading to the restoration of sinus rhythm. Subsequently, he was admitted to the Cardiovascular Intensive Care Unite. Blood tests revealed neutrophilic leukocytosis with elevated inflammatory markers, anemia, and a troponin curve consistent with myocardial injury in the context of sepsis and anemia. Echocardiography demonstrated a left ventricle of normal dimensions with globally depressed function (EF 45%), attributed to apical akinesia. The prosthetic valve was functioning normally, and there were no signs of endocarditic vegetations or pericardial involvement. A transesophageal echocardiogram confirmed the absence of vegetations. Given echocardiographic signs of myocardial ischemia, coronary angiography was performed, revealing a coronary circulation free from significant stenosis. Cultural exams showed positivity for Enterococcus faecalis. A PET–CT revealed the presence of radioisotope uptake around the vascular prosthesis situated in the aortic arch. An Infectious Disease specialist recommended antibiotic therapy with Piperacillin/Tazobactam and Teicoplanin. At the one–month follow–up, the patient remained asymptomatic, free from new febrile episodes. The follow–up echocardiogram indicated improved global systolic function, and inflammatory markers remained consistently negative. Repeat blood cultures were negative. This case illustrates a suspected endocarditis on a prosthetic valve where both transthoraci and transesophageal echocardiography yielded negative results. The use of PET–CT, on the other hand, revealed the presence of vascular graft infection, proving to be a valuable method in this clinical setting.

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

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. 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. 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). 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.

Executive Summary: State-of-the-Art Review: 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 document will concentrate on VGI that impacts both aneurysms and pseudoaneurysms excluding the ascending thoracic aorta.

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.

An ex vivo study of infections of vascular grafts and endografts with scanning electron microscopy

ObjectiveVascular graft and endograft infections (VGEIs) are complicated by high morbidity, mortality, and recurrence rates, notably due to biofilm formation on the graft surface, hardly dislodgeable by the sole anti-infectious treatment. The characteristics of this biofilm are still poorly documented. The aim of this study was to evaluate ex vivo biofilm on removed infected vascular grafts and endografts (VGEs). MethodsExplanted VGEs were prospectively collected from 2019 to 2022 at Bordeaux University Hospital, France. Two samples per graft were used for scanning electron microscopy imaging; one was sonicated, and both grafts’ sides were imaged. ResultsA total of 26 patients were included, 18 with VGEI, eight without any infection (endoleak and/or thrombosis), and 29 VGEs were collected. Microbial documentation was obtained in 83% of VGEIs. A thick layer of fibrin was visible on almost all grafts, mixed with a dense biofilm matrix on infected grafts visible as early as 1 month after the onset of infection. Bacteria were not always visualized on infected grafts’ surface (80% on outer side and 85% on luminal side) but were surprisingly present on one-third of non-infected grafts. There was no significant difference between biofilm, fibrin, and microorganisms’ distribution between the two grafts’ sides. However, there were clear differences between infected and non-infected grafts, since immune cells, bacteria and biofilm were more frequently visualized on both sides of infected grafts (P < .05). Bacteria and immune cells although still visible, were significantly less present after sonication; the number of other elements including biofilm was not significantly different. ConclusionsThe persistence of a thick layer of fibrin and biofilm embedding microorganisms on both sides of infected VGE even after 1 month of infection could be the explanation for the low success rates of conservative management and the usual need for graft removal to treat VGEIs.

Electrospun Chitosan-Based Nanofibrous Coating for the Local and Sustained Release of Vancomycin.

As the population ages, the number of vascular surgery procedures performed increases. Older adults often have multiple comorbidities, such as diabetes and hypertension, that increase the risk of complications from vascular surgery including vascular graft infection (VGI). VGI is a serious complication with significant morbidity, mortality, and healthcare costs. Here, we aimed to develop a nanofibrous chitosan-based coating for vascular grafts loaded with different concentrations of the vancomycin antibiotic vancomycin (VAN). Blending chitosan with poly(vinyl alcohol) or poly(ethylene oxide) copolymers improved solubility and ease of spinning. Thermal gravimetric analysis and Fourier transform infrared spectroscopy confirmed the presence of VAN in the nanofibrous membranes. Kinetics of VAN release from the nanofibrous mats were evaluated using high-performance liquid chromatography, showing a burst followed by sustained release over 24 h. To achieve longer sustained release, a poly(lactic-co-glycolic acid) coating was applied, resulting in extended release of up to 7 days. Biocompatibility assessment using human umbilical vein endothelial cells demonstrated successful attachment and viability of the nanofiber patches. Our study provides insights into the development of a drug delivery system for vascular grafts aimed at preventing infection during implantation, highlighting the potential of electrospinning as a promising technique in the field of vascular surgery.

Nocardia Bacteremia Associated with a Prosthetic Vascular Graft Infection.

Nocardia Bacteremia Associated with a Prosthetic Vascular Graft Infection.

Burden of Candida-related vascular graft infection: a nested-case control study.

We aimed to assess risk factors of candida-related Vascular Graft Infections (VGIs). We did a case-control study (1:4) matched by age and year of infection, nested in a cohort of patient with a history of VGIs. Cases were defined by a positive culture for Candida spp. in biological samples and controls were defined by a positive culture for bacterial strains only in biological samples. Risk factors for Candida-related VGIs were investigated using multivariate logistic regression. Mortality were compared using survival analysis. 16 Candida-related VGIs were matched to 64 bacterial-related VGIs. The two groups were comparable regarding medical history and clinical presentation. Candida-related VGIs were associated with bacterial strains in 88% (14/16). Gas/fluid-containing collection on abdominal CT scan and the presence of an aortic endoprosthesis were risk factors for Candida spp.-related VGIs [RRa 10.43 [1.81-60.21] p = 0.009 RRa and 6.46 [1.17-35.73] p = 0.03, respectively]. Candida-related VGIs were associated with a higher mortality when compared to bacterial-related VGIs (p = 0.002). Candida-related VGIs are severe. Early markers of Candida spp. infection are needed to improve their outcome. The suspicion of aortic endoprosthesis infection may necessitate probabilistic treatment with antifungal agents.

Impact of hospitalist comanagement on vascular surgery inpatient outcomes

ObjectiveIn recent years, hospitalists have been increasingly involved in the medical management of hospitalized surgical patients. This trend has been impacted by the goal of offloading inpatient care from the primary care provider in addition to the presence of an increasing burden of inpatient comorbidities and broader trends in multidisciplinary team-based care of the surgical patient. Multiple studies have demonstrated the clinical benefits associated with the implementation of a hospitalist comanagement service for surgical patients, whereas others have highlighted increases in cost and strain on understaffed medical teams. We aimed to assess the impact of the implementation of a dedicated hospitalist comanagement agreement on outcomes in an academic medical center vascular surgery inpatient service. MethodsInstitutional review board approval was obtained before data collection. The inpatient database was queried for all admissions to the vascular surgery service between January 1, 2007, and December 31, 2017. Given that a hospitalist comanagement agreement was established in 2014, we collected data and compared cohorts admitted to the vascular surgery service before and after January 1, 2014. Patients admitted to the intensive care unit during their hospital stay were excluded, as the hospitalist team was not involved in intensive care unit patient care. We collected data on patient demographics, admission diagnosis, comorbid diseases, and clinical outcomes including hospital length of stay, cardiac morbidity, and mortality. Data were assessed via logistic regression models to investigate the impact on clinical outcomes after the start date of the hospitalist comanagement program. ResultsA total of 1438 patients were included in the analysis, including 866 pre- and 572 posthospitalist comanagement agreement. The mean age was 66.1 (standard deviation 14.0) years, similar in both groups. Overall, 822 (57.2%) patients were male, and 616 (42.8%) were female, similar in both groups. Overall, 67.5% were White, 25.6% Black, and 6.9% were classified as other race. The mean length of stay was 8.2 days overall and was lower in the comanagement group at 7.6 vs 8.6 days in the non-comanagement group (P = .0022). Overall 30-day mortality was 2.5%, similar in both groups (P = .36). The incidence of myocardial infarction was lower in the comanagement group at 2.6% vs 6.0% in the non-comanagement group (P = .0001). Logistic regression modeling controlling for comorbidities demonstrated a 61% odds reduction rate for cardiac events in patients who were comanaged by the hospitalist medicine team (P < .01). Linear regression modeling showed an overall reduced length of stay in the comanagement group by 1.45 days (P < .01) with benefits shown specifically for patients undergoing major amputation, thromboembolectomy, and those with infected vascular grafts (3.8, 7.4, and 8.4 fewer days, respectively). ConclusionsThe implementation of a hospitalist medicine comanagement care system for vascular surgery inpatients was associated with a decrease in cardiac events and hospital length of stay. These findings encourage future investigation into additional clinical benefits and financial implications of hospitalist comanagement in the vascular surgery inpatient population.

Actinomyces spp. Prosthetic Vascular Graft Infection (PVGI): A Multicenter Case-Series and Narrative Review of the Literature.

Actinomycosis represents a challenging and under-reported complication of vascular surgery. Optimal management of Actinomyces spp. prosthetic vascular graft infection (PVGI) is highly uncertain because of the paucity of reports on this disease. We conducted a retrospective case-series of Actinomyces-PVGI that occurred in the last five years in two major university hospitals in northern Italy. We searched for previously published cases in the scientific literature. We report five original cases of Actinomyces spp. prosthetic vascular graft infection following aortic aneurysm repair. Our literature review retrieved eight similar cases. Most patients were immunocompetent males. Most infections were polymicrobial (11/13 cases), with a prevalence of A. odontolyticus involvement (3/13 cases were associated with. Salmonella spp. infection). All cases had a late presentation (≥4 months from graft placement), with 61% associated with an aorto-enteric fistula. All patients received antibiotic therapy, but the duration was highly heterogeneous (from two weeks to life-long antibiotics). The patients without surgical revision experienced septic recurrences (2/13), permanent dysfunction (1/13), or a fatal outcome (2/13), while of the remainder who underwent vascular graft explant, six recovered completely and one developed a periprosthetic abscess. In two cases follow-up was not available. This case-series aims to raise the diagnostic suspicion and to describe the current management of Actinomyces-PVGIs. We highlight a high heterogeneity in antibiotic duration, choice of the antibiotic regimen, and surgical management. Higher reporting rate is advisable to produce better evidence and optimize management of this rare complication of vascular surgery.