Vascular Graft Infections, Mycotic Aneurysms, and Endovascular Infections: A Scientific Statement From the American Heart Association

Mycotic aortic aneurysms: characteristic macroscopic findings in a case series

Infected or mycotic aortic aneurysms (MAAs) are a rare type of aneurysms. Due to the high risk of rupture, MAAs are life-threatening conditions. Early diagnosis and treatment are necessary, yet MAAs are usually found coincidentally. We report 10 patients with MAAs in whom macroscopically, similar coined-sized lesions of the inner aortic wall were seen in all cases. When a coin-sized lesion in the inner aortic wall is seen during open surgical repair of an aortic aneurysm, the surgeon should consider an infectious cause. Microbiological tissue samples should be collected, and additional targeted antibiotic therapy should be started.

Endovascular Therapy for Vascular Graft Infection After Multiple Bypass Surgeries for Aorto-Iliac Occlusive Disease

BACKGROUND

Vascular graft infection is a very complex disease. Although complete excision of the infected grafts with extra-anatomic bypass or in situ reconstruction is a general treatment strategy, some concerns including reinfection in the new graft remain.

CASE REPORT

An 88 year-old man presented to the hospital with abdominal swelling and bleeding. The patient had undergone revascularization for aorto-iliac occlusive disease twice in the past. The first procedure had been performed 15 years previously, with right ilio-femoral bypass grafting for right iliac artery occlusion and stent implantation for left iliac artery stenosis. The second procedure had been performed 10 years previously, with aorta-to-left femoral and left-to-right femoro-femoral bypass grafting because the terminal aorta, the first ilio-femoral bypass graft, and the stent of the left iliac artery had been occluded. The patient was diagnosed with vascular graft infection, and endovascular therapy was selected as the revascularization method prior to graft excision. It was successfully performed using various devices and techniques, followed by graft excision without critical limb ischemia.

CONCLUSION

This case demonstrates that endovascular therapy prior to graft excision can be an alternative revascularization method for vascular graft infection after bypass surgery for aorto-iliac occlusive disease.

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.

Practical Guidance for Clinical Microbiology Laboratories: Microbiologic diagnosis of implant-associated infections

SUMMARYImplant-associated infections (IAIs) pose serious threats to patients and can be associated with significant morbidity and mortality. These infections may be difficult to diagnose due, in part, to biofilm formation on device surfaces, and because even when microbes are found, their clinical significance may be unclear. Despite recent advances in laboratory testing, IAIs remain a diagnostic challenge. From a therapeutic standpoint, many IAIs currently require device removal and prolonged courses of antimicrobial therapy to effect a cure. Therefore, making an accurate diagnosis, defining both the presence of infection and the involved microorganisms, is paramount. The sensitivity of standard microbial culture for IAI diagnosis varies depending on the type of IAI, the specimen analyzed, and the culture technique(s) used. Although IAI-specific culture-based diagnostics have been described, the challenge of culture-negative IAIs remains. Given this, molecular assays, including both nucleic acid amplification tests and next-generation sequencing-based assays, have been used. In this review, an overview of these challenging infections is presented, as well as an approach to their diagnosis from a microbiologic perspective.

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.

Innominate Artery Pseudoaneurysm Requiring Cartilage Tracheal Repair in a Child

Mycotic aneurysms are rare but potentially catastrophic. We report a case of an innominate artery pseudoaneurysm in a 4-year-old patient that caused a tracheoinnominate fistula requiring tracheoplasty with a costal cartilage graft and a homograft iliac artery replacement of the diseased innominate artery, with a successful outcome.

Outcomes Following Different Management of Mycotic Infrarenal Abdominal Aortic Aneurysms

OBJECTIVE

The objective was to present our experience on managing mycotic infrarenal abdominal aortic aneurysm (MIAAA) through a retrospective cohort study.

METHODS

Data of patients with MIAAA managed in our center from July 2016 to October 2022 were retrospectively analyzed. The diagnosis of MIAAA was made based on: (1) preoperative clinical signs of infection; (2) elevated serologic infection parameters; (3) para-aneurysmal infection features on enhanced computed tomography; and (4) positive blood or tissue cultures. All the patients received standard antibiotic therapy. Surgical management including endovascular aneurysm repair (EVAR), initial EVAR followed by open re-operation, and initial open surgical repair (OSR) were conducted according to disease seriosity, physical condition, and patient's will. Infection index and clinical outcome were evaluated during the follow-up time.

RESULTS

A total of 23 patients (21 men; averaged=66.3 years, range=49-79 years) were included, with a mean follow-up time of 19.9 months (range=1-75 months). Bacteria culture from blood or tissue specimen was positive in 15 patients (Salmonella, n=8; Escherichia coli, n=3; methicillin-sensitive Staphylococcus aureus [MSSA], n=1; Klebsiella pneumoniae, n=1; Staphylococcus epidermidis, n=1; Mycobacterium tuberculosis, n=1). Seven patients received OSR as the initial surgical intervention, whereas 14 patients chose EVAR instead. The 2 conservatively managed patients (refused surgery) died within 30 days. The 7 patients who received initial OSR survived till now. Among the 14 patients who underwent initial EVAR, infection deteriorated without exception (14/14, 100%). Three of these patients refused re-operation and died within 6 months. Eleven patients received secondary surgical intervention (10 cases of aneurysm and endograft resection, thorough debridement, subclavian to bi-femoral artery bypass, or in situ aorta reconstruction; 1 case of laparoscopic debridement) and 7 survived the follow-up time. The overall mortality rate was 39.1% (9/23). The mortality rates differed greatly following different intervention methods (merely antibiotic management, 100%; initial open operation, 0%; initial EVAR without secondary operation, 100%; initial EVAR plus secondary operation, 36.4%).

CONCLUSIONS

Open surgical repair is still the first choice for hemodynamically stable and low-risk patients. Merely EVAR is related with disastrous results, which should be reserved as a temporary alternative for patients with ruptured aneurysms, hemodynamic instability or high surgical risk, and followed by timely secondary OSR.

CLINICAL IMPACT

The management of mycotic or primary-infected aortic aneurysm is challenging; treatment remains controversial. Our center has reviewed our experience over the past 6 years and found that open surgical repair is still the first choice for hemodynamically stable and low-risk patients. Merely endovascular aneurysm repair (EVAR) is related with disastrous results, which should be reserved as a temporary alternative for patients with ruptured aneurysms, hemodynamic instability or high surgical risk, and followed by timely secondary open surgical repair.

Long-term Oral Suppressive Antimicrobial Therapy in Infective Endocarditis (SATIE Study): An Observational Study

Background

The role of suppressive antimicrobial therapy (SAT) in infective endocarditis (IE) management has yet to be defined. The objective of this study was to describe the use of SAT in an IE referral center and the patients' outcomes.

Methods

We conducted a retrospective observational study in a French IE referral center (Paris). All patients with IE who received SAT between 2016 and 2022 were included.

Results

Forty-two patients were included (36 male [86%]; median age [interquartile range {IQR}], 73 [61-82] years). The median Charlson Comorbidity Index score (IQR) was 3 (1-4). Forty patients (95%) had an intracardiac device. The most frequent microorganisms were Enterococcus faecalis (15/42, 36%) and Staphylococcus aureus (12/42, 29%). SAT indications were absence of surgery despite clinical indication (28/42, 67%), incomplete removal of prosthetic material (6/42, 14%), uncontrolled infection source (4/42, 10%), persistent abnormal uptake on nuclear imaging (1/42, 2%), or a combination of the previous indications (3/42, 7%). Antimicrobials were mainly doxycycline (19/42, 45%) and amoxicillin (19/42, 45%). The median follow-up time (IQR) was 398 (194-663) days. Five patients (12%) experienced drug adverse events. Five patients (12%) presented with a second IE episode during follow-up, including 2 reinfections (different bacterial species) and 3 possible relapses (same bacterial species). Fourteen patients (33%) in our cohort died during follow-up. Overall, the 1-year survival rate was 84.3% (73.5%-96.7%), and the 1-year survival rate without recurrence was 74.1% (61.4%-89.4%).

Conclusions

SAT was mainly prescribed to patients with cardiac devices because of the absence of surgery despite clinical indication. Five (12%) breakthrough second IE episodes were reported. Prospective comparative studies are required to guide this empirical practice.

Periaortic Graft Infection Following Supracoronary Ascending Aorta Replacement: A Case Report

Periaortic graft infections are a dangerous and extremely rare subtype of aortic graft infections (AGI). We hereby report a unique case of periaortic graft abscess in a 46-year-old male four months following a supracoronary ascending aorta replacement for DeBakey Type 2 dissection, resulting in the successful preservation of the original graft.

Endovascular Repair and Prognosis of Patients with Brucella abortus Infection-Induced Aorto-Iliac Aneurysm

Objective

To establish the endovascular repair and prognosis of patients with aorto-iliac aneurysm and Brucella abortus infection.

Methods

From September 2018 to September 2021, seven cases of Brucella abortus infection with aorto-iliac aneurysm were treated by the endovascular aneurysm repair (EVAR) procedure. Clinical and imaging data were collected to evaluate the therapeutic results, including body temperature, blood culture, imaging manifestations, stent patency and endoleak during the postoperative and follow-up periods.

Results

Except for one patient who died of acute hematemesis and hematochezia just after the admission, seven patients were treated successfully. The aneurysms were completely excluded, and all stent grafts were patent. Patients were followed up for 12-32 months, with an average follow-up of 18.5 ± 9.1 months. There were no cases of endoleak, infection recurrence, gluteal muscle ischemia or spinal cord ischemia during the follow-up period.

Conclusion

It is feasible to treat Brucella abortus-infected aneurysms with the EVAR procedure. The results were optimistic in the short and medium-term. The application of sensitive antibiotics before and after the operation is the cornerstone of endovascular therapy. However, the long-term results require further follow-up.

Development of 3D printed electrospun vascular graft loaded with tetramethylpyrazine for reducing thrombosis and restraining aneurysmal dilatation

Background

Small-diameter vascular grafts have become the focus of attention in tissue engineering. Thrombosis and aneurysmal dilatation are the two major complications of the loss of vascular access after surgery. Therefore, we focused on fabricating 3D printed electrospun vascular grafts loaded with tetramethylpyrazine (TMP) to overcome these limitations.

Methods

Based on electrospinning and 3D printing, 3D-printed electrospun vascular grafts loaded with TMP were fabricated. The inner layer of the graft was composed of electrospun poly(L-lactic-co-caprolactone) (PLCL) nanofibers and the outer layer consisted of 3D printed polycaprolactone (PCL) microfibers. The characterization and mechanical properties were tested. The blood compatibility and in vitro cytocompatibility of the grafts were also evaluated. Additionally, rat abdominal aortas were replaced with these 3D-printed electrospun grafts to evaluate their biosafety.

Results

Mechanical tests demonstrated that the addition of PCL microfibers could improve the mechanical properties. In vitro experimental data proved that the introduction of TMP effectively inhibited platelet adhesion. Afterwards, rat abdominal aorta was replaced with 3D-printed electrospun grafts. The 3D-printed electrospun graft loaded with TMP showed good biocompatibility and mechanical strength within 6 months and maintained substantial patency without the occurrence of acute thrombosis. Moreover, no obvious aneurysmal dilatation was observed.

Conclusions

The study demonstrated that 3D-printed electrospun vascular grafts loaded with TMP may have the potential for injured vascular healing.

Nonspecific Presentation of an Infected Aorto-Iliac Artery Stent Following Endovascular Revision and Stent Insertion

Over the last few decades, the use of covered stent grafts became increasingly popular; as it plays a pivotal role in the management of various atherosclerotic diseases that are rising in both incidence and prevalence. Subsequently, vascular stent infections, although rare, are becoming a well-recognized complication with possibly devastating consequences, owing to the difficulties associated with its diagnosis and treatment. This has prompted significant interest in the condition regarding its pathophysiology, modifiable and non-modifiable risk factors, diagnostic and therapeutic approaches, and the possible implementation of prophylactic measures. We herein present a case of a patient with an infected aortoiliac stent 4 weeks after endovascular revision with atherectomy and additional stent insertion. The patient initially developed nonspecific symptoms and later developed a life-threatening hemorrhage, which was urgently controlled using a percutaneously inserted covered stent at the infected site. Definitive treatment using extraanatomical bypass implantation and an explantation of the infected stents was performed with excellent clinical response.

Infective Native Aortic Aneurysm: a Delphi Consensus Document on Treatment, Follow Up, and Definition of Cure

OBJECTIVE

Evidence is lacking to guide the management of infective native aortic aneurysm (INAA). The aim of this study was to establish expert consensus on surgical and antimicrobial treatment and follow up, and to define when an INAA is considered cured.

METHODS

Delphi methodology was used. The principal investigators invited 47 international experts (specialists in infectious diseases, radiology, nuclear medicine, and vascular and cardiothoracic surgery) via email. Four Delphi rounds were performed, three weeks each, using an online questionnaire with initially 28 statements. The panellists rated the statements on a five point Likert scale. Comments on statements were analysed, statements were revised and added or deleted, and the results were presented in the iterative rounds. Consensus was defined as ≥ 75% of the panel rating a statement as strongly agree or agree on the Likert scale, and consensus on the final assessment was defined as Cronbach's alpha > 0.80.

RESULTS

All 49 panellists completed all four rounds, resulting in 100% participation. One statement was added based on the results and comments of the panel, resulting in 29 final statements: three on need for consensus, 20 on treatment, five on follow up, and one on definition of cure. All 29 statements reached agreement of ≥ 86%. Cronbach's alpha increased for each consecutive round; round 1, 0.85; round 2, 0.90; round 3, 0.91; and round 4, 0.94. Thus, consensus was reached for all statements.

CONCLUSION

INAAs are rare, and high level evidence to guide optimal management is lacking. This consensus document was established with the aim of helping clinicians manage these challenging patients, as a supplement to current guidelines. The presented consensus will need future amendments in accordance with newly acquired knowledge.

Coaxial electrospun Ag-NPs-loaded endograft membrane with long-term antibacterial function treating mycotic aortic aneurysm

The use of endovascular stent-graft has become an important option in the treatment of aortic pathologies. However, the currently used endograft membranes have limited ability to prevent bacterial colonization. This makes them unsuitable for the treatment of mycotic aneurysms, as the infection is prone to progress after endograft implantation. Moreover, even in non-mycotic aortic pathologies, endograft infections can occur in the short or long term, especially for patients with diabetes mellitus or in immune insufficiency conditions. So, this study aimed to develop a kind of Ag-NPs-loaded endograft membrane by coaxial electrospinning technique, and a series of physical and chemical properties and biological properties of the Ag-NPs-loaded membrane were characterized. Animal experiments conducted in pigs confirmed that the Ag-NPs-loaded membrane was basically non-toxic, exhibited good biocompatibility, and effectively prevented bacterial growth in a mycotic aortic aneurysm model. In conclusion, the Ag-NPs-loaded membrane exhibited good biocompatibility, good anti-infection function and slow-release of Ag-NPs for long-term bacteriostasis. Thus, the Ag-NPs-loaded membrane might hold potential for preventing infection progression and treating mycotic aortic aneurysms in an endovascular way.

A Comparison of Surgical Techniques and Outcomes for Primary Infected Abdominal Aortic Aneurysms

BACKGROUND

Primary infected abdominal aortic aneurysms (PIAAAs) are associated with high morbidity and mortality. Three repair approaches include open in-situ repair (OIR), extra-anatomic repair (EAR), and endovascular abdominal aortic aneurysm repair (EVAR). This study is one of the largest single-center case series comparing the outcomes of the different surgical approaches for PIAAA.

METHODS

This is a retrospective cohort study of all patients treated surgically for PIAAA between 2000 and 2021. PIAAA diagnosis was defined as the presence of an abdominal aortic aneurysm with evidence of infection on clinical presentation, laboratory markers, radiology, or surgically. Patients with prior aortic surgery were excluded from this study. Basic demographics were compared across the 3 surgical groups using standard statistical methods. Our primary outcomes included mortality at 1 and 5 years. Kaplan-Meier curves were generated and compared using log-rank testing. Multivariate Cox proportional hazards models were created to assess determinants of mortality.

RESULTS

A total of 43 patients were included in the full cohort. Patients undergoing EVAR more often had diabetes, end-stage renal disease, and coronary artery disease. EVAR was also more often done in patients with a saccular aneurysm rather than fusiform. (93% vs. 70% in EAR and 42% in OIR; P = 0.015). All-cause mortality rates at 1 year were not significantly different between the 3 groups. Survival at 5 years did show a significant benefit of OIR over EVAR and EAR: OIR had an 8% mortality rate with EAR having a 53% rate and EVAR having the highest (72%) mortality rate at 5 years (P = 0.03). Multivariable Cox regression analysis showed that EVAR (aHR 12.1, (95% CI 1.42 to 103.9), P = 0.02) and EAR (aHR 15.1, (95% CI 1.59 to 143.3), P = 0.0.02) had an increased 5-year mortality risk when compared to OIR.

CONCLUSIONS

Repair of primary infected aortic aneurysm is associated with high complication and mortality rates regardless of the approach. In our studied sample, OIR offered an improved long-term survival without added benefits in terms of complication rates. In infected AAA, EVAR should be considered bridging stage between the urgent situation and eventual open repair.

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.

Epidemiology and Risk Factors of Mycotic Aneurysm in Patients With Infective Endocarditis and the Impact of its Rupture in Outcomes. Analysis of a National Prospective Cohort

Background

Several aspects of the occurrence and management of mycotic aneurysm (MA) in patients with infective endocarditis (IE) have not been studied.

Objectives

To determine the incidence and factors associated with MA presence and rupture and to assess the evolution of those initially unruptured MA.

Methods

Prospective multicenter cohort including all patients with definite IE between January 2008 and December 2020.

Results

Of 4548 IE cases, 85 (1.9%) developed MA. Forty-six (54.1%) had intracranial MA and 39 (45.9%) extracranial MA. Rupture of MA occurred in 39 patients (45.9%). Patients with ruptured MA had higher 1-year mortality (hazard ratio, 2.33; 95% confidence interval, 1.49-3.67). Of the 55 patients with initially unruptured MA, 9 (16.4%) presented rupture after a median of 3 days (interquartile range, 1-7) after diagnosis, being more frequent in intracranial MA (32% vs 3.3%, P = .004). Of patients with initially unruptured MA, there was a trend toward better outcomes among those who received early specific intervention, including lower follow-up rupture (7.1% vs 25.0%, P = .170), higher rate of aneurysm resolution in control imaging (66.7% vs 31.3%, P = .087), lower MA-related mortality (7.1% vs 16.7%, P = .232), and lower MA-related sequalae (0% vs 27.8%, P = .045).

Conclusions

MA occurred in 2% of the patients with IE. Half of the Mas occurred in an intracranial location. Their rupture is frequent and associated with poor prognosis. A significant proportion of initially unruptured aneurysms result from rupture during the first several days, being more common in intracranial aneurysms. Early specific treatment could potentially lead to better outcomes.

Contemporary Outcomes of Endovascular and Open Surgical Repair for Mycotic Aortic Aneurysms: A Systematic Review

BACKGROUND

To perform a systematic review on contemporary outcomes of endovascular repair and open surgical repair (OSR) for the treatment of mycotic aortic aneurysm (MAA).

METHODS

A comprehensive literature search on the management of MAAs with endovascular repair or OSR was performed between January 1998 and January 2023. Patient demographics, early and late outcomes were analyzed with respect to treatment modality and MAA location.

RESULTS

Forty-eight articles were included, encompassing a total of 1,358 patients (75.8% male; mean age 66.9 years; 1,372 aneurysms) treated by open (49.8%) or endovascular (50.2%) repair. Salmonella spp., and Staphylococcus spp. were the most prevalent pathogens in Asian and European countries respectively. An increasing number of descending thoracic MAAs were managed by endovascular repair (27.9% vs. 12.8%). Early mortality rates for supra- and infra-renal MAAs managed by endovascular repair were lower than OSR (suprarenal 5.4% vs. 43.2%; infrarenal 1.8% vs. 16.7%). Overall, endovascular repair demonstrated lower intraoperative (1.0% vs. 1.8%) and early mortality (6.5% vs. 15.9) rates than OSR. However, endovascular repair was associated with higher late sepsis rate (5.7% vs. 0.9%) and reintervention rate (17.6% vs. 7.3%). Pooled survival rates at 1- and 5-year were similar between the 2 groups.

CONCLUSIONS

Current literature suggest that endovascular repair is an effective and safe alternative to OSR for descending thoracic, suprarenal, and infrarenal MAAs. However, endovascular repair is associated with higher risk of infection-related complications and reintervention during follow-up.

Outcomes of Endovascular Treatment for Infective Aortic Aneurysms - A Multicenter Retrospective Study

BACKGROUND

In Taiwan, infective native aortic aneurysms (INAAs) are relatively common, so the aim of present study was to demonstrate the comparative outcomes of endovascular repair for thoracic and abdominal INAAs.Methods and Results: Patients with naïve thoracic or abdominal INAAs managed with endovascular repair between 2001 and 2018 were included in this multicenter retrospective cohort. The confounding factors were adjusted with propensity score (PS). Of the 39 thoracic and 43 abdominal INAA cases, 41 (50%) presented with aneurysmal rupture, most of which were at the infrarenal abdominal (n=35, 42.7%) or descending thoracic aorta (n=25, 30.5%). Salmonella spp. was the most frequently isolated pathogen. The overall in-hospital mortality rate was 18.3%. The risks of in-hospital death and death due to rupture were significantly lower with thoracic INAAs (12.8% vs. 23.3%; PS-adjusted odds ratio (OR) 0.24, 95% confidence interval (CI) 0.06-0.96; 0.1% vs. 9.3%; PS-adjusted OR 0.11, 95% CI 0.01-0.90). During a mean follow-up of 2.5 years, the risk of all-cause death was significantly higher with thoracic INAAs (35.3% vs. 15.2%; PS-adjusted HR 6.90, 95% CI 1.69-28.19). Chronic kidney disease (CKD) was associated with death.

CONCLUSIONS

Compared with thoracic INAAs, endovascular repair of abdominal INAAs was associated with a significantly higher in-hospital mortality rate. However, long-term outcomes were worse for thoracic INAAs, with CKD and infections being the most important predictor and cause of death, respectively.

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

OBJECTIVES

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSION

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

Fungal versus non-fungal supra-inguinal prosthetic vascular graft infections: A cohort study

OBJECTIVES

Fungal prosthetic vascular graft infections are rare and mainly supra-inguinal. Current guidelines are based on the few studies that have specifically investigated this population, with few risk factors described. The objective of this study is to compare fungal and non-fungal supra-inguinal prosthetic vascular graft infections (PVGI), describing their specificities, identifying risk factors, and evaluating outcomes.

PATIENTS AND METHODS

This is a single-center retrospective cohort study carried out at the Pitié-Salpêtrière Hospital in Paris, including all patients who were treated for a supra-inguinal PVGI between January 1st, 2009 and February 28th, 2021. Preoperative, intraoperative and postoperative data were compared between fungal and non-fungal PVGI.

RESULTS

Out of the 475 patients screened, 148 developed a supra-inguinal PVGI: 32 fungal and 116 non-fungal. Factors independently associated with fungal PVGI were presence of a prostheto-digestive fistula (OR 5.98; 95% CI 2.29-15.62) and preoperative antibiotic therapy of seven days or more (OR 2.87; 95% CI 1.12-7.38). Mortality rate at 180 days was significantly higher for fungal as compared to non-fungal PVGIs (38% vs. 16% p = 0.009) and for fungal PVGI with prostheto-digestive fistula. However, there was no statistically significant relation between mortality due to prostheto-digestive fistula in contrast with fungal PVGI alone (p = 0.21).

CONCLUSION

Prostheto-digestive fistula was strongly associated with fungal PVGI, which leads us to suggest that in such cases, an anti-fungal agent should be prescribed.

Surgical Outcomes of Infective Native Aortoiliac Aneurysms in a Chilean Academic Center

BACKGROUND

Infective native aortic aneurysms (INAAs), formerly called mycotic aneurysms, remain an uncommon disease with significant heterogeneity among cases; hence, there is lack of solid evidence to opt for the best treatment strategy. The present study aims to describe a 20-year experience at a single institution treating this uncommon condition.

METHODS

Retrospective study of all patients treated for INAA at a single academic hospital in Santiago, Chile, between 2002 and 2022. Clinical characteristics are described, as well as operative outcomes per type of treatment. Nonparametric Mann-Whitney U-test or Kruskal-Wallis tests were performed when appropriate, and results were reported as median and ranges. Survival at given timeframes was determined by a Kaplan-Meier curve, with analysis performed through a Cox regression model.

RESULTS

During the study period, 1,798 patients underwent aortic procedures at our center, of which 35 (1.9%) were treated for INAA. Of them, 25 (71.4%) were male. One patient had 2 INAAs. Median age was 69.5 years (range: 34-89 years). Of the 36 INAAs, the most frequent location was the abdominal and thoracic aorta in 20 (55.5%) and 11 (30.5%) cases, respectively, followed by the iliac arteries in 4 (11.1%) cases. One (2.7%) patient presented a thoracoabdominal INAA. Overall, endovascular treatment associated with long-term antibiotics was used in 20 (57.1%) patients: 4 of them underwent hybrid treatment. Fifteen (42.8%) patients underwent direct aortic debridement followed by in situ or extra anatomic revascularization. There was a significant difference in age between both treatment strategies (a median of 76.5 years for endovascular versus a median of 57 years for open, P = 0.011). The median hospital stay was 15 days (range: 2-70 days). The early complications rate (<30 postoperative days) was 20% (n = 7). Early mortality rate (inhospital or before postoperative 30 days) was 14.2% (n = 5). Median follow-up was 33 months (range: 6-216 months). The overall survival rates at 1, 3, and 5 years were 69.9% (standard error [SE] 8.0), 61.7% (SE 9.8), and 50.9% (SE 11.8), respectively. Five-year survival rate of patients undergoing endovascular treatment compared with open approach was 45.9% (SE 15.1) versus 80.0% (SE 17.8), respectively (P = 0.431). There were no significant differences in survival between open and endovascular treatment, hazard ratio 3.58 (confidence interval 95%: 0.185-1.968, SE ± 0.45 P = 0.454).

CONCLUSIONS

Patients treated by endovascular approach were older than patients treated by open approach. Even though, the open group had a higher 5-year survival rate than the endovascular group, not statically significance differences were found between treatments.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Reinterventions after TEVAR

Thoracic cardiovascular aortic repair is an alternative procedure to open surgery for degenerative thoracic aortic aneurysm and thoracic aortic dissection. The advancements in graft design and imaging techniques have expanded its utility. However, the long-term patency of thoracic endovascular aortic repair (TEVAR) graft is still a concern. This review delves into the literature on re-intervention following TEVAR, highlighting factors that influence the re-intervention rate.

Surely you can't B. cereus: Bacillus cereus infection resulting in spontaneous pseudoaneurysm of a nonaccessed arteriovenous graft

Vascular graft infections are a well-described complication of loop arteriovenous grafts (AVGs) placed for hemodialysis access and are reported to occur in 0.5% to 6.0% of AVGs. The most common microorganisms implicated in these infections are the Staphylococcus species. We present a case of a chronically nonaccessed graft rupture caused by an indolent B. cereus colonization, which is usually a foodborne contaminant. The finding of this organism as the causal agent in an AVG infection warrants further research into the potential emergence of the Bacillus species as a contributing factor in the morbidity and mortality resulting from AVG infection.

Mitral Annular Disjunction: Review of an Increasingly Recognized Mitral Valve Entity

Mitral annular disjunction (MAD) refers to atrial displacement of the hinge point of the mitral valve annulus from the ventricular myocardium. MAD leads to paradoxical expansion of the annulus in systole and may often be associated with mitral valve prolapse (MVP), leaflet degeneration, myocardial and papillary muscle fibrosis, and, potentially, malignant cardiac arrhythmias. Patients with MAD and MVP may present similarly, and MAD is potentially the missing link in explaining why some patients with MVP experience adverse outcomes. Patients with a 5 mm or longer MAD distance have an elevated risk of malignant cardiac arrhythmia compared with those with a shorter MAD distance. Evaluation for MAD is an important component of cardiac imaging, especially in patients with MVP and unexplained cardiac arrhythmias. Cardiac MRI is an important diagnostic tool that aids in recognizing and quantifying MAD, MVP, and fibrosis in the papillary muscle and myocardium, which may predict and help improve outcomes following electrophysiology procedures and mitral valve surgery. This article reviews the history, pathophysiology, controversy, prevalence, clinical implications, and imaging considerations of MAD, focusing on cardiac MRI. Keywords: MR-Dynamic Contrast Enhanced, Cardiac, Mitral Valve, Mitral Annular Disjunction, Mitral Valve Prolapse, Floppy Mitral Valve, Cardiac MRI, Arrhythmia, Sudden Cardiac Death, Barlow Valve © RSNA, 2023.

A rare case of mycotic aortic aneurysm with Clostridium perfringens culture

Key Clinical Message

As only early diagnosis, prompt surgical intervention, and appropriate antibiotic therapy can decrease clostridial MAA mortality rate; keeping in mind a broad differential diagnosis in a patient with sepsis and unusual vascular symptoms is important.

Abstract

Mycotic aortic aneurysm (MAA) is an infrequent but very consequential condition characterized by the pathological disruption of the aorta due to infection. Clostridium perfringens is a bacterium that falls under the taxonomic classification of the genus Clostridium. Although mycotic aneurysm is often not commonly linked with this infection, there are instances when it may function as a causative agent for MAA. Timely diagnosis and thorough therapeutic techniques, including surgical intervention and quick administration of appropriate antibiotics, can potentially reduce the mortality rate associated with clostridial MAA. In this study, we presented a clinical report detailing the diagnosis of a mycotic aneurysm caused by C. perfringens in the thoracic aorta in a 66-year-old male patient with a history of diabetes mellitus and a recent prostate biopsy. Furthermore, we discussed the surgical approach and overall management strategy to address this case.

Fluoroquinolones increase susceptibility to aortic aneurysm and aortic dissection: Molecular mechanism and clinical evidence

Aortic aneurysm (AA) and aortic dissection (AD) are prevalent severe cardiovascular diseases that result in catastrophic complications and unexpected deaths. Owing to the lack of clinically established and effective medications, the only treatment options are open surgical repair or endovascular therapy. Most researchers have focused on the development of innovative medications or therapeutic targets to slow the progression of AA/AD or lower the risk of malignant consequences. Recent studies have shown that the use of fluoroquinolones (FQs) may increase susceptibility to AA/AD to some extent, especially in patients with aortic dilatation and those at a high risk of AD. Therefore, it is crucial for doctors, particularly those in cardiovascular specialties, to recognize the dangers of FQs and adopt alternatives. In the present review, the main clinical observational studies on the correlation between FQs and AA/AD in recent years are summarized, with an emphasis on the relative physiopathological mechanism incorporating destruction of the extracellular matrix (ECM), phenotypic transformation of vascular smooth muscle cells, and local inflammation. Although additional data are required, it is anticipated that the rational use of FQs will become the standard of care for the treatment of aortic diseases.

The Safety and Efficacy of Phage Therapy for Infections in Cardiac and Peripheral Vascular Surgery: A Systematic Review

New approaches to managing infections in cardiac and peripheral vascular surgery are required to reduce costs to patients and healthcare providers. Bacteriophage (phage) therapy is a promising antimicrobial approach that has been recommended for consideration in antibiotic refractory cases. We systematically reviewed the clinical evidence for phage therapy in vascular surgery to support the unlicensed use of phage therapy and inform future research. Three electronic databases were searched for articles that reported primary data about human phage therapy for infections in cardiac or peripheral vascular surgery. Fourteen reports were eligible for inclusion, representing 40 patients, among which an estimated 70.3% of patients (n = 26/37) achieved clinical resolution. A further 10.8% (n = 4/37) of patients showed improvement and 18.9% (n = 7/37) showed no improvement. Six of the twelve reports that commented on the safety of phage therapy did not report adverse effects. No adverse effects documented in the remaining six reports were directly linked to phages but reflected the presence of manufacturing contaminants or release of bacterial debris following bacterial lysis. The reports identified by this review suggest that appropriately purified phages represent a safe and efficacious treatment option for infections in cardiac and peripheral vascular surgery.

Long-Term Suppressive Therapeutic-Drug-Monitoring-Guided Dalbavancin Therapy for Cardiovascular Prosthetic Infections

Dalbavancin represents a promising treatment for cardiovascular prosthetic infections due to its prolonged half-life, bactericidal activity, large spectrum of activity, and excellent biofilm penetration. However, the use of dalbavancin in this setting is limited, and only a few cases have performed therapeutic drug monitoring (TDM) analysis to optimize dosage in suppressive treatments longer than 4 weeks. Our retrospective case series reports the use of dalbavancin in a small cohort of patients with cardiovascular prosthetic infections (cardiac implantable electronic device infections (CEDIs), prosthetic valve endocarditis (PVE), prosthetic vascular graft infections (PVGIs)) treated with dalbavancin as sequential therapy. From May 2019 to May 2023, 14 patients were included: eight cases of PVE (57.1%), seven cases of PVGI (50%), three cases of CEDI (21.4%), and four cases with overlap of infection sites (28.6%). The main pathogen was Staphylococcus aureus (35.7%). Prosthesis replacement was obtained in four patients (28.6%). The median time between symptom onset and the end of treatment was 15 weeks (IQR 7-53), with a median duration of dalbavancin therapy of 8 weeks (IQR 1 to 45 weeks) and 3.5 doses per patient. Among patients managed with TDM-guided strategy, dalbavancin infusion intervals ranged from 4 to 9 weeks. The median length of follow-up was 65 weeks (IQR 23 to 144 weeks). Clinical success was achieved in 10 cases (76.9%); all clinical failures occurred in patients with the implant retained. Among patients monitored by TDM, clinical success was 87.5% vs. 60% in patients treated without TDM. Because of pharmacokinetic individual variability, dalbavancin TDM-guided administration could improve clinical outcomes by individualizing dosing and selecting dosing intervals. This case series seems to suggest a promising role of long-term suppressive dalbavancin treatment for difficult-to-treat cardiovascular prosthesis infection, also with limited surgical indications.

The Outcome of Sac Filling With Fibrin Sealant and Gentamicin After Endovascular Aortic Repair of Brucella-Related Aorto-Iliac Artery Aneurysms: A Retrospective Single-Center Study

PURPOSE

This study aimed to analyze the experience of our center and assess the efficacy of sac filling with fibrin sealant (FS) and gentamicin after endovascular aortic repair (EVAR) in patients with Brucella-related aorto-iliac artery aneurysms.

MATERIALS AND METHODS

All patients who received sac filling with FS and gentamicin after EVAR for Brucella-related aorto-iliac artery aneurysms between March 2019 and September 2022 were reviewed. Before and after sac filling with FS and gentamicin, aneurysm sac thrombosis and endoleak were evaluated using a preloaded catheter to monitor immediate repair outcome. Short- to mid-term outcomes were assessed by the incidence of vascular graft infection (VGI), all-cause mortality, maximum aneurysm diameter, aneurysm sac thrombosis, and other adverse events.

RESULTS

There were 14 patients with Brucella-related aorto-iliac artery aneurysms who underwent sac filling with FS and gentamicin after EVAR. Perioperative death due to myocardial infarction in 1 patient resulted in a postoperative all-cause mortality rate of 7.1% (1/14). All patients received anti-Brucella drugs for a median of 6.0 (range: 3-12) months postoperatively. During a median follow-up period of 15.0 (range 0.5-36) months, the absolute and sagittal maximum diameters of the aorto-iliac aneurysm sac were significantly smaller than preoperation (from 46.3 ± 17.0 to 27.2 ± 16.3 mm, P<.001, and from 39.2 ± 13.1 to 24.0 ± 13.8 mm, P<.001). Two of these patients had a postoperative disappearance of the pseudoaneurysm. One patient was reintervened for bilateral femoral artery bypass surgery. Except for sac filling with gentamicin, all patients received anti-brucella medication for a median of 6.0 (range: 3-12) months. There were no allergic reactions, nephrotoxicity, endoleak, recurrence, VGI, aorta-related or infection-related deaths during the perioperative period and follow-up.

CONCLUSIONS

Sac filling with FS and gentamicin adjunctive to EVAR, with targeted drug delivery to the sites of Brucella-related aorto-iliac artery aneurysm infection lesions, may be an effective solution to control pseudoaneurysm infection and rupture.

CLINICAL IMPACT

Previous Brucella-associated aorto-iliac artery aneurysms have been limited to case reports. This study significantly increased the number of Brucella-associated aorto-iliac aneurysms by 19.7% (14/71) and extended the follow-up to 3 years. In this retrospective study of 14 patients with Brucella-associated aorto-iliac aneurysms treated endovascularly with fibrin sealant and gentamicin for sac filling and targeted administration to infection-related aneurysms, there were no aneurysm-related deaths or infection-related complications and may be an effective solution for controlling aneurysm infection and rupture. And, this approach is an attractive treatment for moving away from long-term dependence on antibiotics but still needs further evaluation.

Danish Nationwide Study on Surgical Treatment of Infective Native Abdominal Aortic Aneurysms

OBJECTIVE

This study aimed to describe surgical trends, survival, and infection related complications (IRC) in a Danish cohort of patients with infective native aortic aneurysms (INAAs).

METHODS

A retrospective nationwide cohort study including all patients in Denmark who were surgically treated for abdominal INAA between 2000 and 2020 was conducted. Patients were identified through the Danish vascular registry, Karbase, which is a database registering all patients treated with vascular surgery in Denmark. Subsequent data on clinical presentation, treatment, all cause mortality, and complications were obtained from the electronic patient charts.

RESULTS

Seventy-five patients were included in the study, of whom 60 (80%) were male, with a median age of 69 (IQR 64, 75) years. Open surgical repair (OSR) was performed in 54 (72%) patients and endovascular aortic repair (EVAR) in 21 (28%). Median follow up was 52 (IQR 32, 103) months. Open repair was consistently the most frequent treatment modality throughout the study period, but EVAR became more frequent over time. The 30 day survival of the total cohort was 97% (94 - 100%). Kaplan-Meier survival estimates for the cohort were 92% (95% CI 85 - 98%), 80% (95% CI 71 - 91%), 63% (95% CI 52 - 78%), and 48% (95% CI 35 - 66%) at one, three, five and 10 years, respectively. Patients treated by EVAR had comparable long term survival to patients treated by OSR, with a hazard ratio of 0.35 (95% CI 0.10 - 1.22), but was associated with better short term survival up to five years. The most common cause of death was sepsis. Five (9%) OSR patients had IRC compared with one (5%) EVAR patient.

CONCLUSION

In this nationwide study of patients treated for abdominal INAA, an increasing number of patients were surgically treated during the study period. Patients treated by EVAR demonstrated long term survival comparable to OSR. The incidence of post-operative IRC was low. These results should be interpreted with caution and prospective registries are needed.

Exogenous Testosterone Replacement Therapy Is Associated with Increased Risk for Vascular Graft Infections Among Hypogonadal Men

BACKGROUND

Vascular graft infections (VGIs) are a major source of morbidity following vascular bypass surgery. Hypogonadal men may be at increased risk for impaired wound healing and infections, but it is unclear if testosterone replacement therapy (TRT) mitigates this risk. We designed this study to evaluate the relationship between hypogonadism and the use of testosterone replacement therapy (TRT) with subsequent risk for developing a VGI.

METHODS

We performed a retrospective analysis of claims in the MarketScan database identifying men greater than 18 years of age who underwent placement of a prosthetic graft in the peripheral arterial circulation from January 2009 to December 2020. Patients were stratified based on diagnosis of hypogonadism and use of TRT within 180 days before surgery. The primary outcome was VGI and the need for surgical excision. The association between hypogonadism and TRT use on risk of VGI was analyzed using Kaplan-Meier plots and multivariate Cox proportional hazards models.

RESULTS

We identified 18,312 men who underwent a prosthetic bypass graft procedure in the upper and lower extremity during the study period, of which 802 (5%) had diagnosis of hypogonadism. Among men with hypogonadism, 251 (31%) were receiving TRT. Patients on TRT were younger, more likely to be diabetic, and more likely develop a VGI during follow-up (14% vs. 8%; P < 0.001) that was in the lower extremity. At 5 years, freedom from VGI was significantly lower for hypogonadal men on TRT than patients not on TRT or without hypogonadism (Log rank P < 0.001). In Cox regression models adjusted for age, diabetes, obesity, smoking, corticosteroid use, and procedure type, hypogonadal men on TRT were at a significantly increased risk of graft infection (hazard ratio (HR):1.94, 95% confidence interval (CI):1.4-2.7; P < 0.001) compared to controls.

CONCLUSIONS

This study demonstrates TRT among hypogonadal men is associated with an increased risk of prosthetic VGIs. Temporary cessation of TRT should be considered for men undergoing prosthetic graft implants, particularly those in the lower extremity.

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.

The Role of Feral Swine in Human Aortic Infection With Brucella Species

Brucellosis is one of the most common zoonotic infections in the world. Human infections are the result of direct exposure to infected animals or ingestion of unprocessed dairy products. While Brucella sp. infection has largely been eliminated from commercial cattle and swine with aggressive vaccination, there is a significant prevalence of Brucella sp. infection in the expanding population of feral swine in the US. We report the surgical treatment of a ruptured mycotic aneurysm of the abdominal aorta due to Brucella suis in a woman living in a rural community with a large population of feral swine. Vascular surgeons should be aware that brucellosis can result in arterial infection and should be considered in the differential diagnosis in patients with a history of exposure to feral swine or the ingestion of unprocessed dairy products.

Cryopreserved Arterial Allografts Versus Rifampin-Soaked Dacron for the Treatment of Infected Aortic and Iliac Aneurysms

BACKGROUND

Infected aortic and iliac artery aneurysms are challenging to treat. Cryopreserved arterial allografts (CAAs) or rifampin-soaked Dacron (RSD) are standard options for in situ reconstruction. Our aim was to compare the safety and effectiveness of CAA versus RSD for these complex pathologies.

METHODS

This is a retrospective review of infected iliac, abdominal, and thoracoabdominal aortic aneurysms treated with either CAAs or RSD between 2002 and 2022 at our institution. The diagnosis was confirmed by intraoperative, radiologic, or microbiological evidence of aortic infection. Perioperative events, 30-day and long-term mortality, reinfection, and reintervention were analyzed.

RESULTS

Thirty patients (17 CAA, 13 RSD) with a mean age of 61 and 68 years, respectively, were identified. The infected aneurysm was most commonly suprarenal or infrarenal. Culture-negative infections were present in 47% of the CAA group and 54% in the RSD group. Early major morbidity was 57% and 54% for the CAA and RSD, respectively. Thirty-day mortality was similar between groups (18% vs. 23% CAA vs. RSD, P ≥ 0.99). Median follow-up was longer in the RSD group (14.5 months vs. 13 months). Overall survival at 1 and 5 years was 80.8% and 64.8% in the CAA group and 69.2% and 57.7% in the RSD group. Reinterventions only occurred with CAA repairs and indications included graft occlusion (2), multiple pseudoaneurysms and reinfection (1), and hemorrhagic shock caused by graft rupture (1). Freedom from reintervention at 1 and 3 years was 87.5% and 79.5% (CAA group) versus 100% and 100% (RSD, P = 0.06). Freedom from reinfection at 1 year was 100% in both groups, while at 3 years it was 90.9% for the CAA group and 100% for the RSD group (P = 0.39).

CONCLUSIONS

Infected aortic and iliac aneurysms have high early morbidity and mortality. CAA and RSD had similar outcomes in our series; CAA trended toward higher reintervention rates. Both remain viable options for complex scenarios but require close surveillance.

Use of Omniflow® II Biosynthetic Graft for the Treatment of Vascular Graft and Endograft Infections

BACKGROUND

Vascular graft/endograft infection is a rare but life-threatening complication of cardiovascular surgery and remains a surgical challenge. Several different graft materials are available for the treatment of vascular graft/endograft infection, each having its own advantages and disadvantages. Biosynthetic vascular grafts have shown low reinfection rates and could be a potential second best after autologous veins in the treatment of vascular graft/endograft infection. Therefore, the aim of our study was to evaluate the efficacy and morbidity of Omniflow® II for the treatment of vascular graft/endograft infection.

METHODS

A multicenter retrospective cohort study was performed to evaluate the use of Omniflow® II in the abdominal and peripheral region to treat vascular graft/endograft infection between January 2014 and December 2021. Primary outcome was recurrent vascular graft infection. Secondary outcomes included primary patency, primary assisted patency, secondary patency, all-cause mortality, and major amputation.

RESULTS

Fifty-two patients were included with a median follow-up duration of 26.5 (10.8-54.8) months. Nine (17%) grafts were implanted in intracavitary position and 43 (83%) in peripheral position. Most grafts were used as femoral interposition (n = 12, 23%), femoro-femoral crossover (n = 10, 19%), femoro-popliteal (n = 8, 15%), and aorto-bifemoral (n = 8, 15%) graft. Fifteen (29%) grafts were implanted extra-anatomically and 37 (71%) in situ. Eight patients (15%) presented with reinfection during follow-up, most of these patients received an aorto-bifemoral graft (n = 3, 38%). Intracavitary vascular grafting had a 33% (n = 3) reinfection rate and peripheral grafting 12% (n = 5; P = 0.025). The estimated primary patencies at 1, 2, and 3 years were 75%, 72%, and 72% for peripherally located grafts and 58% (at all timepoints) for intracavitary grafts (P = 0.815). Secondary patencies at 1, 2, and 3 years were 77% (at all timepoints) for peripherally located prostheses and 75% (at all timepoints) for intracavitary prostheses (P = 0.731). A significantly higher mortality during follow-up was observed in patients who received an intracavitary graft compared to patients with a peripheral graft (P = 0.003).

CONCLUSIONS

This study highlights the efficacy and safety of the Omniflow® II biosynthetic prosthesis for the treatment of vascular graft/endograft infection, in absence of suitable venous material, with acceptable reinfection, patency, and freedom of amputation prevalences, especially in replacing peripheral vascular graft/endograft infection. However, a control group with either venous reconstruction or another alternative graft is needed to make firmer conclusions.

Surviving the nonsurvivable combination of a mycotic aneurysm progressing into a concomitant aorto-bronchial- and aorto-esophageal fistula, a case report

BACKGROUND

Aortic mycotic aneurysms are a rare but life-threatening condition and may be associated with aorto-bronchial- and aorto-esophageal fistulas. Although both very rare, they carry a high mortality and require (urgent) surgical intervention. Surviving all three conditions concomitantly is extraordinary. We describe a patient who underwent staged repair of such combined defects.

Staphylococcus aureus Adhesion and Biofilm Formation on Vascular Polyester Grafts are Inhibited In Vitro by Triclosan

OBJECTIVE

This study evaluated Staphylococcus aureus adhesion and biofilm formation on vascular grafts, which has seldom been investigated.

METHODS

Adhesion and biofilm formation capabilities of three methicillin susceptible S. aureus strains (one biofilm forming reference strain and two clinical isolates) on five different vascular biomaterials were evaluated in vitro, including polyester (P), P + gelatin (PG), P + collagen (PC), PC + silver (PCS), and PCS + triclosan (PCST). Staphylococcus aureus adhesion on grafts was evaluated after one hour of culture and biofilm formation after 24 hours of culture by four different methods: spectrophotometry after crystal violet staining; sonicate fluid culture; metabolic assay; and scanning electron microscopy (SEM). Optical density was compared using Mann-Whitney pairwise test, and bacterial counts using Wilcoxon pairwise test.

RESULTS

PCST grafts were most efficient in preventing S. aureus adhesion and biofilm formation, regardless of the method used. Bacterial counts and metabolic activity were significantly lower on PCST grafts after 24 hours (5.65 vs. 9.24 [PCS], 8.99 [PC], 8.82 [PG], and 10.44 log10 CFU/mL [P]; p < .015), and only PCST grafts were bactericidal. Biofilm formation was significantly diminished on PCST grafts compared with all other grafts (p < .001). Bacterial viability and metabolic activity after 24 hours were more impaired on PG compared with PC graft, and were surprisingly higher on PCS compared with PC grafts. Biofilm biomass formed after exposure to P, PG, PC, and PCS grafts was also reduced after 24 hours of incubation with PCST grafts (p < .001). After 24 hours, few bacteria were visible by SEM on PCST grafts, whereas bacterial biofilm colonies were clearly identified on other graft surfaces.

CONCLUSION

Triclosan impregnated PCST grafts appeared to interfere with S. aureus adhesion from early stages of biofilm formation in vitro. Silver impregnation was not efficient in preventing biofilm formation, and collagen coating promoted S. aureus biofilm formation more than gelatin coating.

Highlights and Perioperative Implications from the 2022 American College of Cardiology and American Heart Association Guidelines for Diagnosis and Management of Aortic Disease

As the understanding of aortic diseases and their complications grow, increasing importance of uniformity in diagnosis and management is crucial for optimal care of this patient population. The 2022 American College of Cardiology and American Heart Association Guidelines for Diagnosis and Management of Aortic Disease discusses these considerations in detail. The purpose of this review is to highlight essential recommendations that are of relevance to the perioperative physician who manages these patients. A few notable points include, shared decision-making with patients, creation of multidisciplinary aortic teams, lower diameter thresholds for surgery in certain situations, and increased testing for patients with heritable aortic diseases. In addition to briefly reviewing basics of aortic diseases, the authors discuss changes to guidelines that are especially relevant to perioperative care.

Cryopreserved arterial allografts vs rifampin-soaked Dacron for the treatment of infected aortic and iliac grafts

OBJECTIVE

Aortic and iliac graft infections remain complex clinical problems with high mortality and morbidity. Cryopreserved arterial allografts (CAAs) and rifampin-soaked Dacron (RSD) are options for in situ reconstruction. This study aimed to compare the safety and effectiveness of CAA vs RSD in this setting.

METHODS

Data from patients with aortic and iliac graft infections undergoing in situ reconstruction with either CAA or RSD from January 2002 through August 2022 were retrospectively analyzed. Our primary outcomes were freedom from graft-related reintervention and freedom from reinfection. Secondary outcomes included comparing trends in the use of CAA and RSD at our institution, overall survival, perioperative mortality, and major morbidity.

RESULTS

A total of 149 patients (80 RSD, 69 CAA) with a mean age of 68.9 and 69.1 years, respectively, were included. Endovascular stent grafts were infected in 60 patients (41 CAA group and 19 RSD group; P ≤ .01). Graft-enteric fistulas were more common in the RSD group (48.8% RSD vs 29.0% CAA; P ≤ .01). Management included complete resection of the infected graft (85.5% CAA vs 57.5% RSD; P ≤ .01) and aortic reconstructions were covered in omentum in 57 (87.7%) and 63 (84.0%) patients in the CAA and RSD group, respectively (P = .55). Thirty-day/in-hospital mortality was similar between the groups (7.5% RSD vs 7.2% CAA; P = 1.00). One early graft-related death occurred on postoperative day 4 due to CAA rupture and hemorrhagic shock. Median follow-up was 20.5 and 21.5 months in the CAA and RSD groups, respectively. Overall post-discharge survival at 5 years was similar, at 59.2% in the RSD group and 59.0% in the CAA group (P = .80). Freedom from graft-related reintervention at 1 and 5 years was 81.3% and 66.2% (CAA) vs 95.6% and 92.5% (RSD; P = .02). Indications for reintervention in the CAA group included stenosis (n = 5), pseudoaneurysm (n = 2), reinfection (n = 2), occlusion (n = 2), rupture (n = 1), and graft-limb kinking (n = 1). In the RSD group, indications included reinfection (n = 3), occlusion (n = 1), endoleak (n = 1), omental coverage (n = 1), and rupture (n = 1). Freedom from reinfection at 1 and 5 years was 98.3% and 94.9% (CAA) vs 92.5% and 87.2% (RSD; P = .11). Two (2.9%) and three patients (3.8%) in the CAA and RSD group, respectively, required graft explantation due to reinfection.

CONCLUSIONS

Aorto-iliac graft infections can be managed safely with either CAA or RSD in selected patients for in situ reconstruction. However, reintervention was more common with CAA use. Freedom from reinfection rates in the RSD group was lower, but this was not statistically significant. Conduit choice is associated with long-term surveillance needs and reinterventions.

Finite element-based feasibility study on utilizing heat flux sensors for early detection of vascular graft infections

Aortic vascular graft infections have high morbidity and mortality rate, however, patients often do not show symptoms. Continuous implant surface monitoring will allow for early detection of infections on implant surfaces, which allows for antibiotic treatment prior to biofilm formation. We explore the possibility of using heat flux sensors mounted on an aortic vascular graft to sense the localized heat production at the onset of infectious growth. We apply Finite Element Model simulations to demonstrate changes of the heat transfer coefficient depending on different pulsatile flow parameters. We determine various differences, the main influence being the distance travelled from the inlet of the simulation with the highest heat transfer coefficient closest to the inlet and decreasing along the direction of travel of the fluid. The determined range of heat transfer coefficients of 200 to 4800 W/m2 was applied to a second simulation of the thermal environment of the implant. We determined the heat transfer efficiency of the aortic graft system depending on different graft materials and thicknesses. We are further able to determine that the early detection of infection is possible by comparing the simulated amount of heat flux produced locally with the resolution of a commercial heat flux sensor.

Aortic Endograft Infection: Diagnosis and Management

Aortic endograft infection (AEI) is a rare but life-threatening complication of endovascular aneurysm repair (EVAR). The clinical features of AEI range from generalized weakness and mild fever to fatal aortic rupture or sepsis. The diagnosis of AEI usually depends on clinical manifestations, laboratory tests, and imaging studies. Management of Aortic Graft Infection Collaboration (MAGIC) criteria are often used to diagnose AEI. Surgical removal of the infected endograft, restoration of aortic blood flow, and antimicrobial therapy are the main components of AEI treatment. After removing an infected endograft, in situ aortic reconstruction is often performed instead of an extra-anatomic bypass. Various biological and prosthetic aortic grafts have been used in aortic reconstruction to avoid reinfection, rupture, or occlusion. Each type of graft has its own merits and disadvantages. In patients with an unacceptably high surgical risk and no evidence of an aortic fistula, conservative treatment can be an alternative. Treatment results are determined by bacterial virulence, patient status, including the presence of an aortic fistula, and hospital factors. Considering the severity of this condition, the best strategy is prevention. When encountering a patient with AEI, current practice emphasizes a multidisciplinary team approach to achieve an optimal outcome.

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.