In Situ Reconstruction in Native and Prosthetic Aortic Infections Using Cryopreserved Arterial Allografts

Endovascular treatment of aorta-iliac arterial pseudoaneurysm caused by Brucella

We aimed to analyze the feasibility of endovascular treatment for brucellosis-related aorta-iliac artery pseudoaneurysm. We did a statistical analysis that among the 11 cases, the thoracic aorta was involved in 3 cases, the abdominal aorta was involved in 6 cases, and the iliac artery was involved in 2 cases. Five patients had a history of contact with cattle and sheep, 3 had a history of drinking raw milk, 10 patients had a fever before the operation, and 11 patients had positive serum agglutination test. Blood culture was positive in 2 patients. All patients were given anti-brucellosis treatment immediately after diagnosis. One died of aortic rupture 5 days after emergency endovascular gastrointestinal bleeding. Endovascular-covered stent implantation and active anti-brucellosis therapy were used to treat 10 patients. The follow-up period was 8 years without aortic complications or death for all patients. We think early diagnosis and a combination of anti-brucellosis drugs and endovascular therapy may be the first choice for treating the pseudoaneurysm caused by Brucella.

Contemporary Experience of the Neo-Aortoiliac System (NAIS) Procedure: A Case Series with Review of the Literature

OBJECTIVES

Aortic graft infection is a life-threatening complication that can result in death, amputation, sepsis, aorto-enteric fistula, and pseudoaneurysm formation. After explantation of the infected graft, options for reconstruction include extra-anatomic bypass or in-line reconstruction using antibiotic-coated prosthetic graft, cryopreserved allograft, or a neo-aortoiliac system (NAIS) using autogenous femoral veins. While the NAIS procedure has shown promising results, there is relatively limited clinical experience due the magnitude and morbidity of the surgery. In this study, we reviewed our single-center experience using the NAIS procedure and performed a systematic review of the contemporary literature over the past decade.

METHODS

A retrospective review was performed on all patients undergoing NAIS reconstruction with autogenous femoral vein conduits at a single institution from 2010 to 2022. Pubmed, Embase, and Cochrane Library databases were queried for studies published from 2012 to 2022 to identify those reporting on outcomes of patients undergoing the NAIS procedure. Outcome variables included early and late mortality, major complications including amputation, graft or conduit related complications, re-infection, and re-intervention. Additional variables collected include patient demographics, operative technique, and follow-up.

RESULTS

There were 14 patients included in our case series with 30-day mortality of 21%. At a mean follow-up of 22 months, complication rate was 64.3%, re-intervention rate was 14.3%, re-infection rate was 7.1%, and amputation rate was 7.1%. On review of the literature, 12 studies ultimately met criteria to be included in analysis with a combined total of 368 patients. Pooled averages included 30-day mortality of 9.0%, re-intervention rate of 20.5%, re-infection rate of 5.6%, and amputation rate of 6.5%.

CONCLUSIONS

The NAIS procedure for management of aortic graft infection is a formidable procedure with significant early mortality and morbidity. This treatment should be considered in the context of other revascularization options for management of an aortic graft infection.

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

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

Breaking the Limit of Cardiovascular Regenerative Medicine: Successful 6-Month Goat Implant in World's First Ascending Aortic Replacement Using Biotube Blood Vessels

This study investigated six-month outcomes of first models of ascending aortic replacement. The molds used to produce the Biotube were implanted subcutaneously in goats. After 2-3 months, the molds were explanted to obtain the Biotubes (inner diameter, 12 mm; wall thickness, 1.5 mm). Next, we performed ascending aortic replacement using the Biotube in five allogenic goats. At 6 months, the animals underwent computed tomography (CT) and histologic evaluation. As a comparison, we performed similar surgeries using glutaraldehyde-fixed autologous pericardial rolls or pig-derived heterogenous Biotubes. At 6 months, CT revealed no aneurysmalization of the Biotube or pseudoaneurysm formation. The histologic evaluation showed development of endothelial cells, smooth muscle cells, and elastic fibers along the Biotube. In the autologous pericardium group, there was no evidence of new cell development, but there was calcification. The histologic changes observed in the heterologous Biotube group were similar to those in the allogenic Biotube group. However, there was inflammatory cell infiltration in some heterologous Biotubes. Based on the above, we could successfully create the world's first Biotube-based ascending aortic replacement models. The present results indicate that the Biotube may serve as a scaffold for aortic tissue regeneration.

Cryopreserved arterial allografts vs autologous vein for arterial reconstruction in infected fields

OBJECTIVE

Peripheral arterial infections are rare and difficult to treat when an in situ reconstruction is required. Autologous vein (AV) is the conduit of choice in many scenarios. However, cryopreserved arterial allografts (CAAs) are an alternative. We aimed to assess our experience with CAAs and AVs for reconstruction in primary and secondary peripheral arterial infections.

METHODS

Data from patients with peripheral arterial infections undergoing reconstruction with CAA or AV from January 2002 through August 2022 were retrospectively analyzed. Patients with aortic- or iliac-based infections were excluded.

RESULTS

A total of 42 patients (28 CAA, 14 AV) with a mean age of 65 and 69 years, respectively, were identified. Infections were secondary in 31 patients (74%) and primary in 11 (26%). Secondary infections included 10 femoral-femoral grafts, 10 femoropopliteal or femoral-distal grafts, five femoral patches, four carotid-subclavian grafts, one carotid-carotid graft, and one infected carotid patch. Primary infection locations included six femoral, three popliteal, and two subclavian arteries. In patients with lower extremity infections, associated groin infections were present in 19 (56%). Preoperative blood cultures were positive in 17 patients (41%). AVs included saphenous vein in eight and femoral vein in six. Intraoperative cultures were negative in nine patients (23%), polymicrobial in eight (21%), and monomicrobial in 22 (56%). Thirty-day mortality occurred in four patients (10%), two due to multisystem organ failure, one due to graft rupture causing acute blood loss and myocardial infarction, and one due to an unknown cause post-discharge. Median follow-up was 20 months and 46 months in the CAA and AV group, respectively. Graft-related reintervention was performed in six patients in the CAA group (21%) and one patient in the AV group (7%). Freedom from graft-related reintervention rates at 3 years were 82% and 92% in the CAA and AV group, respectively (P = .12). Survival rates at 1 and 3 years were 85% and 65% in the CAA group and 92% and 84% in the AV group (P = .13). Freedom from loss of primary patency was similar with 3-year rates of 77% and 83% in the CAA and AV group, respectively (P = .25). No patients in either group were diagnosed with reinfection.

CONCLUSIONS

CAAs are an alternative conduit for peripheral arterial reconstructions when AV is not available. Although there was a trend towards higher graft-related reintervention rates in the CAA group, patency is similar and reinfection is rare.

Early and late outcomes of surgical repair of mycotic aortic aneurysms: A 30-year experience

OBJECTIVE

Mycotic aortic aneurysm and its associated complications are often catastrophic. In this study, we examined the early and late outcomes of surgical repair of mycotic aortic aneurysm at our center over the last 3 decades.

METHODS

We retrospectively reviewed our prospectively maintained aortic surgery database with supplemental adjudication of medical records. Aortic infection was confirmed through clinical, radiological, intraoperative, pathological, and treatment evidence.

RESULTS

Seventy-five patients (median age, 68 years; interquartile range, 62-74) who underwent surgical repair of a mycotic aortic aneurysm between 1992 and 2021 were included. Almost all patients (n = 72; 96%) presented with symptoms, including 26 patients (35%) with rupture, and many underwent urgent or emergency repair (n = 64; 85%). Sixty-one patients underwent open repair, and 14 patients underwent hybrid or endovascular repair. Infection-specific adjunct techniques included rifampin-soaked grafts (n = 16), omental pedicle flaps (n = 21), and antibiotic irrigation catheters (n = 8). There were 15 early deaths (20%), including 10 of the 26 patients (38%) who presented with rupture; however, persistent stroke, paraplegia or paraparesis, and renal failure necessitating dialysis were uncommon (each <5%). Almost all early survivors (52/60; 87%) were discharged with long-term antibiotic therapy. Estimated survival at 2, 6, and 10 years was 55.7% ± 5.8%, 39.0% ± 5.7%, and 26.9% ± 5.5%, respectively.

CONCLUSIONS

A substantial proportion of patients with mycotic aortic aneurysm present with rupture and generally require urgent or emergency repair. Operative mortality and complications are common, especially for patients who present with rupture, and late survival is poor.

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.

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.

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.

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.

Reconstruction of primary and secondary aortic infections with an antimicrobial graft

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Infection of Vascular Prostheses: A Comprehensive Review

Vascular graft or endograft infection (VGEI) is a complex disease that complicates vascular-surgery and endovascular-surgery procedures and determines high morbidity and mortality. This review article provides the most updated general evidence on the pathogenesis, prevention, diagnosis, and treatment of VGEI. Several microorganisms are involved in VGEI development, but the most frequent one, responsible for over 75% of infections, is Staphylococcus aureus. Specific clinical, surgical, radiologic, and laboratory criteria are pivotal for the diagnosis of VGEI. Surgery and antimicrobial therapy are cornerstones in treatment for most patients with VGEI. For patients unfit for surgery, alternative treatment is available to improve the clinical course of VGEI.

Ten-year experience with cryopreserved vascular allografts in the Croatian Cardiovascular Tissue Bank

The Croatian Cardiovascular Tissue Bank (CTB) was established in June 2011. Activities managed by CTB are processing of heart valves and blood vessels, as well as quality control, storage, medical release and distribution of allografts. The aim of this report is to present CTB's vascular tissue activities and retrospectively evaluate the outcomes of their use in the University Hospital Centre Zagreb. Between June 2011 and July 2021, 90 vascular allografts (VAs) from 55 donors after brain death were referred to CTB. Only 54% of VAs met the tissue quality requirements while 46% of tissues were discarded. The most frequent reasons for discard were unacceptable morphology and initial microbiological contamination. Altogether 42 VAs were released for transplantation and 37 of them were used in 27 surgical procedures. The most common indication for surgery was prosthetic graft or stent infection. According to the anatomic position of vascular reconstruction, patients were divided in the aortic and peripheral reconstruction group. A total of 23 patients were treated. In the aortic reconstruction group 58% of patients did not experience any graft-related complications. In the group of patients who underwent peripheral reconstruction significant incidence of reinfection was observed highlighting it as a major graft-related complication. Despite the small patient groups and limited duration of follow-up, presented clinical outcomes provide valuable information on the efficacy of vascular allografts. Additional clinical results collected on a larger patient groups and comparison to other reconstructive treatment options are necessary.

Management and Clinical Outcome of Aortic Graft Infections: A Single-Center Retrospective Study

BACKGROUND

This study aimed to evaluate the outcome of various treatment options for aortic graft infection (AGI) patients and identify factors affecting their prognosis.

METHODS

The data of AGI patients from January 2008 to December 2019 were retrospectively collected and analyzed. The primary endpoints were 30-day mortality and perioperative complication-related morbidity; the secondary endpoints were re-infection (RI) rates, primary and secondary graft patency, overall mortality, duration of antibiotic therapy, and the number of antibiotic types used in treatment.

RESULTS

There was no significant difference in the 30-day mortality and perioperative-related complications between the conservative treatment, in-situ reconstruction (ISR), and extra-anatomic reconstruction (EAR) groups. The ISR group had lower re-infection rates and better overall survival rates than the EAR and conservative treatment groups. Different bypass graft conduits had no significant influence on the RI rate or primary and secondary graft patency. AGI patients infected with high-virulence pathogens had higher RI and overall mortality rates than those infected with low virulence pathogens, but this was not statistically significant. Initial procedures prior to the AGI also had no influence on the prognosis of AGI patients. Patients undergoing ISR or EAR surgery received antibiotic therapy for a longer duration than patients undergoing conservative treatment. Patients without RI received more types of antibiotics than patients with RI.

CONCLUSIONS

ISR had lower RI rates and better overall survival rates than EAR and conservative treatment and may be a better choice for patients with AGI. Several factors were found to have no influence on patients' prognosis however, further studies are required.

The Femoral Vein as a Long-Term Aorto-Iliac Graft for Aortic Infection and Aortitis

Background

Reconstruction of the aorto-iliac segment with femoral vein (FV) as substitute for infected synthetic grafts or mycotic aneurysms constitutes the most sustainably convenient alternative. The aim of this study was to evaluate the long-term outcome of up to 16 years of follow-up, analysing the morphologic adaption of the FV with special emphasis on the distal and proximal anastomoses.

Methods

We conducted a retrospective study of 22 patients with 109 computed tomography angiograms (CTAs) treated between August 2001 and January 2020 in case of aortic infection/aortitis. Morphologic changes like anastomotic dilatation/stenosis as well as changes of FV wall thickness were retrospectively analysed in pre- and postoperative CTAs.

Results

Elective procedure was done in 17/22 (77%) cases, and 5/22 (23%) patients required emergent surgery. The median follow-up was 91.5 months (P₂₅;P₇₅ = 21;117). Cross-sectional diameter of proximal (20.38 ± 3.77 vs 22.04 ± 3.97 mm, p = 0.007) and distal anastomoses (13.05 ± 4.23 vs 14.61 ± 5.19 mm, p = 0.05) increased significantly, as well as the proximal and distal anastomotic areas (3.36 ± 1.29 vs 4.32 ± 1.63 mm², p = 0.04 and 0.99 ± 0.48 vs 1.25 ± 0.72 mm², p = 0.023, respectively). Venous wall thickness was significantly reduced at the anastomotic site (1.74 ± 0.46 vs 1.24 ± 0.31 mm, p = 0.001). The upper thigh diameter did not differ before and after harvesting of the FV (161.6 ± 29.1 vs. 178.2 ± 23.3 mm, p = 0.326, respectively).

Conclusion

This long-term CTA follow-up study showed that the FV wall becomes thinner at the anastomotic site, and the anastomoses dilate with time without rupture. The FV is a durable conductor after replacement of the aorto-iliac segment due to aortic infection. Further CTA studies from more centres are warranted to evaluate the risk of vein rupture.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Results of cryopreserved arterial allograft replacement for thoracic and thoracoabdominal aortic infections

BACKGROUND

Primary and secondary thoracic aortic infections are rare but associated with high morbidity and mortality. There is currently no consensus on their optimal treatment. Arterial allografts have been shown to be resistant to bacterial colonization. Complete excision of infected material, especially synthetic grafts, combined with in situ aortic repair is considered the best treatment of abdominal aortic infections. The aim of this study was to assess the management of thoracic and thoracoabdominal aortic infections using arterial allografts.

METHODS

Between January 2009 and December 2017, all patients with thoracic and thoracoabdominal aortic native or graft infections underwent complete excision of infected material and in situ arterial allografting. The end points were the early mortality and morbidity rates and early and late rates of reinfection, graft degeneration, and graft-related morbidity.

RESULTS

Thirty-five patients with a mean age of 65.6 ± 9.2 years were included. Twenty-one (60%) cases experienced graft infections and 14 (40%) experienced native aortic infections. Eight (22.8%) patients had visceral fistulas: 5 (14.4%) prosthetic-esophageal, 1 (2.8%) prosthetic-bronchial, 1 (2.8%) prosthetic-duodenal, and 1 (2.8%) native aortobronchial. In 12 (34.3%) cases, only the descending thoracic aorta was involved; in 23 (65.7%) cases, the thoracoabdominal aorta was involved. Fifteen (42.8%) patients died during the first month or before discharge: 5 of hemorrhage, 4 of multiorgan failure, 3 of ischemic colitis, 2 of pneumonia, and 1 of anastomotic disruption. Eleven (31.5%) patients required early revision surgery: 6 (17.1%) for nongraft-related hemorrhage, 3 (8.6%) for colectomy, 1 (2.9%) for proximal anastomotic disruption, and 1 (2.9%) for tamponade. One (2.9%) patient who died before discharge experienced paraplegia. One (2.9%) patient experienced stroke. Six (17.1%) patients required postoperative dialysis. Among them, four died before discharge. The mean length of stay in the intensive care unit was 11 ± 10.5 days; the mean length of hospital stay was 32 ± 14 days. During a mean follow-up of 32.3 ± 23.7 months, three allograft-related complications occurred in survivors (15% of late survivors): one proximal and one distal false aneurysm with no evidence of reinfection and one allograft-enteric fistula. The 1-year and 2-year survival rates were 49.3% and 42.5%, respectively.

CONCLUSIONS

Although rare, aortic infections are highly challenging. Surgical management includes complete excision of infected tissues or grafts. Allografts offer a promising solution to aortic graft infection because they appear to resist reinfection; however, the grafts must be observed indefinitely because of the risk of late graft complications.

Treatment of infectious aortic disease with bovine pericardial tube grafts

OBJECTIVES

Our aim was to evaluate the mid-term outcomes of bovine pericardial tube graft repair for infectious aortic disease in any aortic segment.

METHODS

Between May 2015 and July 2020, 45 patients were treated for infectious aortic disease of the native (n = 9) aorta or after (endo-)graft (n = 36) implantation with bovine pericardial tube grafts. Clinical, infectious details, outcomes and follow-up data were evaluated.

RESULTS

All aortic segments underwent pericardial tube graft or bifurcational replacement: the aortic root (n = 12, 27%), ascending aorta (n = 18, 40%), aortic arch (n = 7, 16%), descending aorta (n = 5, 11%), thoraco-abdominal aorta (n = 6, 13%) and abdominal aorta (n = 18, 40%) including the iliac arteries (n = 14, 31%). Organ fistulation (n = 15, 33%) was the most common underlying pathology. Seven patients (16%) expired in-hospital secondary to ongoing sepsis (n = 5, 11%), respiratory failure (n = 1, 2%) and unknown cause (n = 1, 2%). A fungal infection was predictive for in-hospital mortality (P = 0.026, odds ratio: 19.470). After a median follow-up of 11 [first quartile: 2, third quartile 26] months, 9 additional patients (20%) expired and 1 patient developed a postoperative spondylodiscitis at the level of the aortic tube graft. Hence, freedom from proven aortic graft re-infection was 98%.

CONCLUSIONS

Orthotopic aortic reconstruction using bovine pericardial tube grafts to treat infectious aortic disease is possible in any aortic segment. Organ fistulation is a frequently observed disease mechanism requiring concomitant treatment. Granted, the early attrition rate is substantial, but after the initial period, both survival and freedom from re-infection appear encouraging.

The role of the pedicle omental flap in ruptured abdominal aortic aneurysm: a case report and literature review

A ruptured infrarenal abdominal aortic aneurysm (rAAA) is associated with an in-hospital mortality rate of 40% and an overall mortality rate of 60–80%. Open surgical repair for rAAA remains the principal method of treatment when endovascular repair is not available. Graft infection occurs in 1–4% of patients at 5 years, with a high incidence following emergency treatment. Other graft-related complications include pseudoaneurysm, graft occlusion and aorto-enteric fistula. This case report describes a 66-year-old male patient that was admitted to hospital complaining of intense abdominal pain, low blood pressure and tachycardia. He was diagnosed with a rAAA and treated using segmental resection of the abdominal aorta followed by reconstruction with a synthetic Dacron prosthesis. A pedicle omental flap was wrapped around the prosthetic graft and it was also used to fill the retroperitoneal cavity in order to reduce the risk of graft-related complications. Computed tomography angiography after 6 months showed good integration of the aortic prosthetic graft and the viability of the omental flap. In our opinion, vascular surgeons should consider the pedicle omental flap when they perform open surgical repair for rAAA in order to reduce the incidence of graft-related complications.

Treatment and Outcomes of Aortic Graft Infections Using a Decision Algorithm

BACKGROUND

Aortic graft infection (AGI) is a rare but devastating complication requiring both explant of the infected prosthesis and lower extremity revascularization. Despite a variety of methods to treat AGI, there is a paucity of evidence that describes comparative outcomes. Moreover, controversy exists surrounding what the optimal repair strategy is with limited descriptions of how these techniques should be employed in this complex group of patients. Therefore, the purpose of this analysis was to review our experience with AGI management while highlighting a practice philosophy that can achieve acceptable outcomes.

METHODS

All AGI patients between 2002-2019 were reviewed. The primary end-point was 30-day mortality. Secondary end-points included complications, re-infection, unplanned re-operation and all-cause mortality. Kaplan-Meier methodology was used to estimate time to events. Cox regression models were employed to identify association between patient factors and operative strategy with survival. Subgroup analysis included outcome comparison among four different operative approaches(extra-anatomic bypass with aortic ligation [EAB] and in-situ reconstruction [ISR] using either NAIS, cryopreserved allograft [Cryo], or antibiotic-soaked prosthetic grafts [Other]).

RESULTS

142 patients (male-69%, mean age 67 ± 11 years) were reviewed. Median time to AGI presentation was 52 (IQR 16-128) months. ISR was performed in 70% (n = 99)[ISR: NAIS-49% (n = 49), Cryo, 33% (n = 33) and Other-23% (n = 23)]. EAB was used in 26% (n = 37), of which 57% (n = 21) were staged repairs[no reconstruction, 4%: intraoperative death-2, AGI removal without reconstruction-2]. A graft enteric erosion/fistula was identified in 39% (n = 55). Mean follow-up time was 14 ± 27 (median 2.2[IQR 0.1-16]) months. Overall, 30-day mortality was 21% and 69% (n = 98) experienced a complication. The most common complications were pulmonary (35%;n = 50), vascular (28%;n = 39), gastrointestinal (22%;n = 31) and renal (21%;n = 30). Freedom from re-infection at one and three years was 78 ± 5% and 73 ± 6% while freedom from unplanned re-operation was 50 ± 5% and 40 ± 6%, respectively. Corresponding one- and five-year freedom from all-cause mortality was 67 ± 4% and 53 ± 4%. When stratified by the four different repair strategies, unadjusted rates of postoperative complications and mortality were not different. However, EAB patients had more renal complications. All-cause mortality predictors included age (HR 1.04, 95%CI 1.01-1.1; P = 0.003), CHF (HR 2.7, 1.3-5.7; P = 0.01), and graft enteric erosion/fistula (HR 2.2, 1.3-3.8;P = 0.005) while total graft excision was protective (HR 0.34, 0.2-0.7; P = 0.003).

CONCLUSIONS

AGI repair, regardless of operative strategy, results in significant early morbidity, and mortality. The need for unplanned re-operation is common; however, long-term survival is acceptable in appropriately selected patients. Re-infection risk mandates life-long surveillance and consideration of indefinite anti-microbial suppression in certain subgroups. Due to the complexity and intensity of care, all AGI should be treated, when possible, at centers performing high-volume aortic surgery.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Long-term results of cryopreserved allografts in aortoiliac graft infections

OBJECTIVE

Different graft materials have been proposed for in situ reconstruction in the setting of vascular graft infection (VGI). We analyzed the long-term outcomes after in situ aortoiliac reconstruction with cryopreserved allografts.

METHODS

We performed a retrospective analysis of patients who had undergone in situ aortoiliac reconstruction with cryopreserved arterial allografts for VGI from 2000 to 2015. The end points were the perioperative and long-term mortality and graft-related complications, including stenosis, occlusion, pseudoaneurysm, and reinfection.

RESULTS

A total of 33 patients (91% male) with a median age of 67 years (range, 53-83 years) had undergone in situ aortoiliac reconstruction with cryopreserved allografts. The 30-day mortality was 6% (n = 2); both deaths were related to the allograft (one early allograft-enteric fistula and one graft rupture). Another two patients had experienced early (≤30 days) graft-related events (one allograft-enteric fistula and one graft limb occlusion), for an early graft-related complication rate of 12% (n = 4). Of the 31 discharged patients, 13 (42%) had died after a median of 47 months (range, 2-97 months). The median follow-up for the 18 remaining patients was 96 months (range, 10-146 months). The estimated survival at 1, 3, and 5 years was 88%, 81%, and 66%, respectively. Nine patients (29%) had experienced at least one of the following graft-related events during follow-up, including graft stenosis requiring intervention in five (16%), graft occlusion in four (13%), pseudoaneurysm in three (10%), and reinfection in two patients (6%). The estimated freedom from any first graft-related event at 1, 3, and 5 years was 78%, 71%, and 62%, respectively. The estimated primary patency and primary assisted patency at 1 and 3 years was 87% and 79%, and 90% and 83%, respectively.

CONCLUSIONS

In situ aortoiliac reconstruction with cryopreserved allografts to treat VGI was associated with relevant perioperative graft-related complications. Although the reinfection rate was acceptable, other graft-related complications were frequent in the long term, in particular, graft occlusion and stenosis.

Novel prefabricated bovine pericardial grafts as alternate conduit for septic aortoiliac reconstruction

OBJECTIVE

Infection of prosthetic aortic grafts represents a serious complication with high morbidity and mortality. Replacement with autologous material is recommended; however, in its absence, biological material should be favored. In the present retrospective cohort study, we evaluated the short- and midterm results with the use of commercially available prefabricated bovine pericardium grafts (BPGs) used for the management of aortic graft infection or aortic reconstructive surgery in the presence of systemic infection.

METHODS

We performed a retrospective analysis of patients in whom BPGs had been used for aortic reconstruction at two vascular centers. Prefabricated vascular pericardium grafts were preferred over other biological reconstruction techniques for selected cases. Comorbidities, procedure-related details, perioperative morbidity, clinical outcomes, and mortality were analyzed.

RESULTS

From 2014 to 2019, 21 patients had received BPGs at two Austrian vascular centers. Their median age was 63 years (interquartile range [IQR], 55-71 years), the patients were predominantly male (76%), and the median body mass index was 25.3 kg/m² (IQR, 21.7-27.3 kg/m²). The major comorbidities included arterial hypertension, peripheral artery disease, smoking, and chronic pulmonary disease. The indications for surgery were vascular graft or endograft infection in 62% and aortic reconstruction in the presence of systemic infection in 38%. Three patients (14%) had aortoenteric fistulas. Surgery was technically successful in all cases. The median follow-up was 21.6 months (IQR, 6.0-34.6 months). The 30-day mortality was 9.5%. The 1- and 2-year overall survival was 84% and 75%, respectively. Of the 21 patients, 89% had remained free of recurrent infection. One of the two reinfections had resolved after treatment of the underlying focus. At 2 years, the primary and assisted primary patency rates were 86% and 94%, respectively. No limbs were lost during follow-up.

CONCLUSIONS

Prefabricated BPGs represent a promising alternative for the management of aortic graft infections and aortoiliac reconstruction in the presence of systemic infection.

Early outcomes of native and graft-related abdominal aortic infection managed with orthotopic xenopericardial grafts

OBJECTIVE

Reconstruction of infected aortic cases has shifted from extra-anatomic to in situ. This study reports the surgical strategy and early outcomes of abdominal aortic reconstruction in both native and graft-related aortic infection with in situ xenopericardial grafts.

METHODS

Included in the analysis are 21 consecutive patients (mean age, 69 years; 20 male) who underwent abdominal xenopericardial in situ reconstruction of native aortic infection (4) and endovascular (4) or open (13) graft aortic infection between July 2017 and September 2019. All repairs were performed on an urgent basis, but none were ruptured. All patients were followed up with clinical and biologic evaluation, ultrasound at 3 months, and computed tomography scan at 6 months and 1 year.

RESULTS

Technical success was 100%; 8 patients were treated with xenopericardial tubes and 13 with bifurcated grafts. Thirty-day mortality was 4.7% (one death due to pneumonia with respiratory hypoxic failure in critical care.). Six patients (28%) developed acute kidney injury, four (19%) requiring temporary dialysis; five fully recovered and one died. Four patients (19%) required a return to the operating room. After a median follow-up of 14 months (range, 1-26 months), overall mortality was 19% (n = 4). Two patients presented with recurrent sepsis after reconstruction, leading to death due to multiorgan failure. Other patients (17/21) have discontinued antibiotics with no evidence of recurrence of infection clinically, radiologically, or on blood tests. Computed tomography scans at 1 year demonstrated no stenosis or graft dilation and one asymptomatic left graft branch thrombosis. Primary patency is 95%.

CONCLUSIONS

In situ xenopericardial aortic reconstruction is a safe and effective management strategy for both native and graft-related abdominal aortic infection with good short-term results. The graft demonstrates appropriate resistance to infection such that reliable eradication of infection in this vascular bed is possible. Longer follow-up is required in future studies to determine the durability of the reconstruction and need for reinterventions.

Successful surgical management of coarctation of the aorta with infective endaortitis and splenic abscess: a case report

Infective endaortitis with a splenic abscess is an extremely rare and fatal complication of coarctation of the aorta. We herein describe a 19-year-old female patient with a 2-month history of intermittent fever with progressive abdominal and leg pain. Aortic computed tomography angiography showed a rapidly progressive poststenotic saccular aneurysm immediately distal to the coarctation. Enhanced abdominal computed tomography showed a severe splenic abscess. During the operation, the infected spleen was resected first. We subsequently removed all of the diseased aorta and performed in situ aortic reconstruction with an artificial tube graft and without extracorporeal circulation. The patient had an uneventful postoperative clinical course and recovered very well during the 4-year follow-up. In summary, our case report details the successful surgical treatment of coarctation of the aorta with infective endaortitis and a splenic abscess and thoroughly discusses the indications and key notes for surgery without extracorporeal circulation in this complex disease.

A Mycotic Common Iliac Artery Pseudoaneurysm of Indeterminate Etiology

We present the unusual case of a mycotic right common iliac artery pseudoaneurysm caused by the methicillin-susceptible Staphylococcus aureus (MSSA) of indeterminate etiology in a healthy 57-year-old man with no risk factors for infection, trauma, or malignancy. The patient initially presented with worsening subacute right lower quadrant pain and was found to have a pseudoaneurysm of the right common iliac artery. Given concern for rupture on a computed tomography angiogram (CTA), he underwent exclusion of the pseudoaneurysm with a covered stent. At the time of presentation, he had no signs or symptoms of infection. However, the patient developed fever, chills, and worsening right lower quadrant pain 13 days after the index operation and was found to have a leukocytosis, blood cultures positive for MSSA, and progressive soft-tissue changes involving the right common iliac artery on CTA consistent with infection. He was definitively treated with stent explantation, aggressive debridement and replacement with an in situ cryopreserved bypass, and short-term suppressive antibiotic therapy.

Influence of the new standardized clinical cryopreservation/slow thawing protocol on immunogenicity of arterial allografts in rats

Objectives and design

At the present time there are two waiting list for patients with vascular prosthetic infection indicated for arterial transplantation in the Czech Republic. The inclusion of each patient for cold-stored or cryopreserved arterial transplantation is the preference of indicating surgeon. In this experimental work we studied the immunogenicity of rat aortal allografts treated by our new clinical cryopreservation/slow thawing protocol.

Material and methods

Brown-Norway (BN) (N = 6, 203–217 g) or Lewis (LEW) (N = 6, 248–254 g) abdominal aortal grafts treated in accordance with our new clinical cryopreservation/slow thawing protocol were orthotopically transplanted to Lewis recipients (N = 12, 191–245 g). Aortal wall histology and infiltration by recipient immune cells, as well as donor specific anti MHC class I and II antibodies in recipient serum were studied in both isografts and allografts on day 30 postransplant. Core data of cryopreserved allografts were compared to our previous data of cold-stored aortal allografts treated in accordance with our clinical cold-storage protocol.

Results

Cryopreserved allografts showed regular morphology of aortal wall with clear differentiation of all three basic anatomical layers on day 30 postransplant. Intimal layer showed no hyperplasia, luminal surface was covered by endothelial cells. No statistical difference was observed in tunica media thickness between isografts and allografts. The medial layer showed no necrosis, shrinkage or immunoglobuline G deposition in any experimental group. The adventitial infiltration by immune cells was significantly higher (P<0.05) in allografts. Cryopreserved allografts showed significant lower activation of both cell- and antibody mediated immunity compared to historical data of cold-stored allografts.

Conclusion

Aortal wall histology of rat allografts treated by our new standardized clinical cryopreservation/slow thawing protocol was comparable to that of the cryopreserved isografts on day 30 posttranspant. The immunogenicity of cryopreserved aortal allografts was significantly lower compared to that of cold-stored aortal allografts.

Tubular Reconstruction with Bovine Pericardium Xenografts to Treat Native Aortic Infections

BACKGROUND

The treatment of aortic infections is complex, and the material of reconstruction remains discussed. Several alternatives were suggested in the literature. The current consensus is the use of biological material. The aim of this study was to evaluate the short-term results of bovine pericardium xenografts.

METHODS

Between November 2016 and June 2019, we included consecutively all the patients presenting with native aortic infections in which arterial reconstruction was carried out with tubular bovine pericardium grafts sutured longitudinally. We collected the preoperative, peroperative, and postoperative clinical, radiological, biological, and bacteriological characteristics. The recurrence of infection, the graft failures, and the morbimortality were analyzed.

RESULTS

Twelve patients including three women were treated. Their mean age was 68.4 ± 9 years. They presented 2 thoracic, 4 thoracoabdominal, 4 abdominal, and 2 aortoiliac aneurysms. The diagnosis was made using angio-CT in all the cases and was confirmed by positron emission tomography (PET) scan in 7 cases and blood cultures in 9 cases. Peroperative cultures were positive in 11 cases. Antibiotics were given in 9 patients before operation for a median duration of 9 (3-19) days and in all the patients postoperatively for a median duration of 42 (1-540) days. The median follow-up was 355 (98-839) days. Six medical complications occurred, including 2 (16.6%) leading to death in the immediate postoperative period. No reoperation was needed. The PET scan returned positive in 1/10 cases (10%) during the follow-up. The diameter of the grafts was preserved, without any defect observed on the angio-CT.

CONCLUSIONS

Short-term results showed a mechanical resistance to infection of the bovine pericardium. This biological material offers a promising alternative with multiple advantages including availability, simplicity of preparation, and adaptability to the various locations of the aortic infection.

Twenty-year experience with cryopreserved arterial allografts for vascular infections

OBJECTIVES

The aim of this study was to analyse outcomes over 2 decades using cryopreserved vascular allografts to treat vascular infection.

METHODS

We conducted a retrospective study of patients identified from our institutional database who were treated for primary or secondary vascular infection using implanted allografts.

RESULTS

Between October 1992 and May 2014, 54 patients underwent surgery for vascular infection out of 118 patients implanted with cryopreserved vascular allografts. The 52 patients for whom we had full information form the basis of the study with a 96% follow-up. The average age was 64 ± 11 years; 87% were men; 65% had previous vascular surgery; 19% had emergency operations. A total of 75% of the patients had aortoiliofemoral infections. Five patients underwent surgery with cardiopulmonary bypass. Fifty percent required more than 1 allograft and 15% had concomitant procedures. Seventy-three percent (38/52) of specimen cultures yielded positive results with polymicrobial flora in 29%. Surgical specimens most frequently grew coagulase-negative staphylococci. The early postoperative reoperation rate was 15% for allograft-related complications. There were 20 (38%) early deaths, including deaths of acute myocardial infarction, anastomosis rupture and persistent sepsis and shock. Uncontrolled infection leading to septic shock and multiple organ failure was the cause of death in 50% of the cases. The mean duration of freedom from allograft reintervention was 12.2 years. The mean duration of freedom from allograft occlusion or limb loss was 12.1 years [95% confidence interval (CI) 9.9-14.4]. Of the 32 surviving patients, we had patency information for 66% obtained by angiography or computed tomography. The mean survival for the cohort was 5.9 years (95% CI 3.9-7.8). Mean freedom from cardiovascular infection-related death was 9.3 years (95% CI 7.2-11.4).

CONCLUSIONS

Allografts can be indicated for treatment of primary/secondary infection and have remarkable results in multimorbid patients. Patients with vascular infection have a high-risk profile, around 40% mortality during the first 6 months, with reduction in overall mortality thereafter. We believe that allografts may play a role in the surgical treatment of vascular infection.

Cryopreserved Venous Allografts in Supra-inguinal Reconstructions: A Single Centre Experience

OBJECTIVE

This study introduces a novel technique for supra-inguinal arterial reconstructions with cryopreserved femoral vein and caval allografts with a low re-infection rate and an acceptable graft re-intervention rate on early mid term analysis.

METHODS

Patients treated from February 2012 to March 2018 with cryopreserved venous allograft reconstructions owing to infection in the supra-inguinal area were reviewed retrospectively. The primary end points were re-infection and the treatment related mortality rate. Secondary end points were 30 and 90 day and overall mortality and graft re-intervention rate.

RESULTS

Of the 23 patients treated with cryopreserved venous allografts for infection in aorto-iliac area, 21 (91%) patients underwent reconstruction with cryopreserved femoral veins and two (9%) with vena cava. Indications for treatment were aortic graft infections (n = 12 [52%]), mycotic aneurysms (n = 5 [22%]), femorofemoral prosthetic infections (n = 3 [13%]), anastomotic pseudo-aneurysms (n = 2 [9%]), and aortic thrombosis with intestinal spillage (n = 1 [4%]). In hospital and 90 day mortality were 9% (n = 2); overall treatment related mortality during the median follow up of 15 months was 13% (n = 3). During the follow up, two allografts were re-operated on owing to anastomotic dilatation and one because of re-infection, resulting in a re-intervention rate of 13% (n = 3). None of the grafts was lost and there were no amputations. At the end of follow up 17 patients (74%) were alive. Kaplan-Meier estimation for survival was 76% (95% confidence interval [CI] 57%-95%) at one year and 70% (95% CI 49%-91%) at two years.

CONCLUSION

Cryopreserved venous allografts appear to be an infection resistant and reasonably safe reconstruction material in the aorto-iliac axis based upon the early mid term analysis from a single centre experience. Further research is needed to compare their performance with other biological reconstruction material.

Recommendations for management of infected aortic pathology based on current evidence

The management of infection involving the abdominal aorta requires clinical decisions based on patient factors and the nature of the infectious process. Any infection occurring after endovascular aortic aneurysm repair or open aortic replacement grafting should be treated promptly with appropriate systemic antibiotic therapy. Once a vascular prosthesis becomes infected, surgical treatment is necessary. There should be a low threshold for graft excision and extra-anatomic bypass in the presence of fistula or abscess cavity, when feasible entire graft should be excised. In selected patients, graft excision with in situ aorta reconstruction is an appropriate option using an autogenous femoral vein, cryopreserved allograft, or a prosthetic graft impregnated with antibiotic. The replaced in situ aortic graft should be covered with an omental pedicle. For primary aortic graft infections, endovascular treatment may act as a bridge to more definitive treatment; or, in the absence of gross retroperitoneal infections, endovascular grafting alone with prolonged systemic antibiotic therapy is a viable option, particularly in patients not fit for open surgical procedures.

Editor's Choice - Cryopreserved Allografts for Arterial Reconstruction after Aorto-Iliac Infection: A Systematic Review and Meta-Analysis

OBJECTIVE

Native and aortic graft infections are rare, but they represent one of the most life threatening complications of vascular surgery. Several materials and surgical approaches have been developed so far. Among them, cryopreserved allografts have been proposed as a treatment option. A systematic review and meta-analysis was conducted to investigate the role of cryopreserved allografts for arterial reconstruction after aorto-iliac infection.

METHODS

The current meta-analysis was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Patient baseline characteristics were investigated, along with 30 outcomes after use of cryopreserved arterial allografts for reconstruction after aorto-iliac infection. Pooled proportions with 95% CIs of outcome rates were calculated.

RESULTS

A total of 31 studies, including 1,377 patients, finally participated in the meta-analysis. Among the early outcomes, 30 day mortality was 14.91% (95% CI 11.78-18.31). Peri-anastomotic rupture/allograft disruption rate was 5.90% (95% CI 2.77-9.88), while pooled aneurysmal degeneration/allograft dilatation was 4.99% (95% CI 1.60-9.68). A pooled rate of 3.11% (95% CI 1.60-4.98) was estimated for pseudoaneurysm formation after the use of cryopreserved arterial allografts, while the allograft thrombotic/stenotic complication rate and peri-anastomotic infection were 12.19% (95% CI 7.90-17.15) and 3.32% (95% CI 1.90-5.03), respectively. Mortality during follow up was 19.24% (95% CI 11.97-27.58), while allograft related mortality during follow up was 3.58% (95% CI 1.56-6.15). A pooled allograft related re-operation rate was estimated at 24.87% (95% CI 17.89-32.51).

CONCLUSIONS

The use of cryopreserved allograft seems to be a safe and durable option with acceptable outcomes for treatment of aorto-iliac infection.

Systematic Review and Meta-Analysis on the Management of Open Abdominal Aortic Graft Infections

OBJECTIVE

Aortic graft infection (AGI) is a disastrous complication with an incidence of 0.2-6% in operated patients. With little or no high quality evidence, the best treatment option remains unclear. Therefore, the literature on the management of open abdominal AGI was systematically reviewed to determine optimal treatment.

METHODS

In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic review and meta-analysis was conducted for AGI. MEDLINE, Embase, and the Cochrane Database of Systematic Reviews were searched. Methodological quality was assessed using the Methodological Index for Non-randomised Studies (MINORS) score. Primary outcomes were 30 day mortality and one year survival. Secondary outcomes were survival, infection recurrence, limb salvage, and graft patency.

RESULTS

Of 1574 studies identified, 32 papers were included in the study. The overall quality of the studies was moderate, with an average MINORS score of 11.9. Pooled overall 30 day mortality and one year survival were 13.5% (95% CI 10.5-16.4) and 73.6% (95% CI 68.8-78.4), respectively. The lowest 30 day mortality and highest one year survival were found for in situ repair compared with extra-anatomic repair and for prosthetic grafts compared with venous grafts or arterial allografts. The infection recurrence rate was highest for prosthetic grafts.

CONCLUSIONS

There is a lack of well designed, qualitative comparative studies making conclusive recommendations impossible. The current best available data suggests that partial graft removal should be avoided and the lowest 30 day mortality and best one year survival are achieved with in situ repair using prosthetic grafts. Initiatives such as the MAGIC database to collaboratively collect prospective data are an important step forward in obtaining more solid answers on this topic.

Peripheral artery reconstructions using cryopreserved arterial allografts in infected fields

OBJECTIVE

Cryopreserved human arterial allografts are a recognized acceptable alternative for vascular reconstruction when other traditional conduits are either unavailable or contraindicated. We reviewed our experience using cryopreserved arterial allografts for peripheral artery reconstructions in contaminated and infected surgical fields.

METHODS

A single-center, retrospective review was conducted of 57 patients who underwent a peripheral vascular reconstruction using a cryopreserved arterial allograft from January 2002 through July 2017. Indications for repair included removal of infected prosthetic bypass (n = 29), revascularizations in contaminated fields (n = 11), primary arterial repair in the setting of infection (n = 10), and infected vascular closure devices (n = 7). Aorta-based repairs were excluded. Demographics, index procedural details, postoperative complications, and conduit patency were analyzed. Primary end points included conduit-related mortality and graft failure as measured by reinfection, hemorrhage, or aneurysmal degeneration. Mean follow-up for the study is 27.8 months (range, 2-125 months).

RESULTS

A total of 57 peripheral vascular reconstructions using cryopreserved arterial allografts were performed during the 15-year period. Among the 22 women and 35 men treated, the mean age was 61 years. The vascular beds involved included iliofemoral (n = 39), femoropopliteal or femoral-distal (n = 10), axillosubclavian or brachial (n = 2), mesenteric (n = 3), and carotid (n = 3) arteries. Adjunctive muscle flap coverage of the allograft conduit was performed in the majority of cases (61%; n = 35). The 30-day mortality was 9%; one death was directly related to conduit insertion. The 30-day conduit-related complication rate was 14% and included hemorrhage from the graft requiring return to the operating room (n = 4) and graft infection (n = 4). The late conduit-related complication rate was 15.8% and included graft infection (n = 1), graft thrombosis (n = 3), major amputation resulting from conduit failure (n = 1), pseudoaneurysm degeneration requiring repair (n = 2), graft hemorrhage (n = 1), and symptomatic graft stenosis (n = 1).

CONCLUSIONS

A cryopreserved arterial allograft is a useful alternative conduit for peripheral vascular reconstruction in infected or contaminated surgical fields when other autologous or prosthetic conduits are either unavailable or contraindicated. In the immediate postoperative period, these repairs demonstrate acceptable resistance to graft failure and reinfection, particularly in conjunction with adjunctive rotational muscle flap coverage. Late conduit-related complications appear to be infrequent.

A meta-analysis of outcomes of in-situ reconstruction after total or partial removal of infected abdominal aortic graft

INTRODUCTION

There is currently a lack of evidence for the relative effectiveness of partial resection (PR) and total resection (TR) before managing abdominal aortic graft infection (AGI). Most authorities agree that TR is mandatory for intracavitary AGI in patients with favorable conditions but there is an increasing number of patients with severe comorbidities for whom this approach is not suitable, resulting in a prohibitive mortality rate. The purpose of this study was to determine the most appropriate indication for TR or PR.

EVIDENCE ACQUISITION

A meta-analysis was conducted on the rates of early/late mortality, amputations and reinfection. A meta-regression was performed with eight variables: patient age, male prevalence, presence of virulent or nonvirulent organisms, urgency, omentoplasty and follow-up.

EVIDENCE SYNTHESIS

Twenty-one studies and 1052 patients were included. For TR and PR, the rates of early mortality and reinfection were 16.8% and 10.5%, 11% and 27%, respectively. For TR urgency and male gender were associated with increased rate of early mortality and male gender, PDF and virulent organisms were associated with increased risk of reinfection. For PR no statistical correlation was analyzable except for PDF with increased risk of reinfection.

CONCLUSIONS

Early mortality rates are higher for TR and reinfection rates are higher for PR. For TR early mortality increases in urgent cases and it is suggested that alternative option must be discussed, reinfection decreases in the presence of nonvirulent organisms and TR seems optimal. For TR and PR reinfection increases in presence of PDF and alternative technique may be more appropriate.

Aortic treatment of native infection by reconstruction with the Omniflow II biologic prosthesis

Aortic infection is a challenging condition. Fortunately, surgical revision of infected aorta with in situ reconstruction can provide long-term cure. The material for aortic repair remains an area of debate. The Omniflow II (LeMaitre Vascular, Burlington, Mass) prosthesis is a biosynthetic graft made to resist long-term degeneration and allows growth of host tissue with reduction of the risk of arterial infection. It has already been used for peripheral bypass with very low infection rates. Herein, we describe an original case of first-line native aorta replacement by a straight Omniflow II biologic prosthesis for infected aortic aneurysm.

Infrarenal Aortic Endograft Infection: A Single-Center Experience

PURPOSE:

Endograft infection is an infrequent but one of the most serious and challenging complications after endovascular aortic repair. The aim of this study was to assess the management of this complication in a tertiary center.

CASE SERIES:

A retrospective analysis of a prospective database was performed including all patients who underwent elective endovascular abdominal aortic repair (EVAR) from 2003 to 2016 in a tertiary center. Seven cases of endograft infection were identified during the follow-up period from a total of 473 (1.48%) EVAR. Most frequent symptoms at presentation were fever (71.4%) and lumbar pain (57.1%). One case developed an early infection, while 6 cases were diagnosed as late infections. Mean time from endograft placement to symptom presentation was 28.3 months (2-91.5 months). Gram-positive cocci were the microorganisms most commonly isolated in blood cultures (66%). Two cases were managed with endograft removal and aortic reconstruction with a cryopreserved allograft, 2 cases with surgical drainage, and 2 cases exclusively with antibiotic therapy. In 1 case, the diagnosis was performed postoperatively based on intraoperative findings associated with positive graft cultures; and graft explantation was performed with "in situ" reconstruction using a Dacron graft. Perioperative mortality was 42.9%. One-year mortality was 57.1%. Mean follow-up was 21.5 months.

CONCLUSION:

Endograft explantation is the gold standard of treatment; however, given the overall high morbi-mortality rates of this pathology, a tailored approach should always be offered depending on the patient's overall condition. Conservative management can be an acceptable option in those patients with short life expectancy and high surgical risk.

Surgical Treatment of Symptomatic Aortic Aneurysm in a Patient with Anti-neutrophil Cytoplasmic Antibody-associated Vasculitis: Case Report and Review of the Literature

Vasculitis is an heterogeneous group of syndromes, which shares inflammation of blood vessel wall as the main feature. Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a necrotizing vasculitis, with few or no immune deposits, predominantly affecting small vessels (i.e., capillaries, venules, arterioles, and small arteries), associated with ANCAs specific for myeloperoxidase or proteinase 3. Clinical manifestations may be heterogeneous but an involvement of lungs and kidneys frequently occurs. AAV of large vessels is a very rare condition whose standard therapy is medical approach. Surgical revascularization has been described in selected patients after medical failure or in emergent settings. We report the case of a patient affected by symptomatic infrarenal aortic aneurysm related to AAV, who underwent in-situ reconstruction by means of cryopreserved homograft.

Open Repair of Mycotic Abdominal Aortic Aneurysms With Biological Grafts: An International Multicenter Study

BACKGROUND

The treatment of mycotic abdominal aortic aneurysm requires surgery and antimicrobial therapy. Since prosthetic reconstructions carry a considerable risk of reinfection, biological grafts are noteworthy alternatives. The current study evaluated the durability, infection resistance, and midterm outcome of biological grafts in treatment of mycotic abdominal aortic aneurysm.

METHODS AND RESULTS

All patients treated with biological graft in 6 countries between 2006 and 2016 were included. Primary outcome measures were 30- and 90-day survival, treatment-related mortality, and reinfection rate. Secondary outcome measures were overall mortality and graft patency. Fifty-six patients (46 males) with median age of 69 years (range 35-85) were included. Sixteen patients were immunocompromised (29%), 24 (43%) had concomitant infection, and 12 (21%) presented with rupture. Bacterial culture was isolated from 43 (77%). In-situ aortic reconstruction was performed using autologous femoral veins in 30 patients (54%), xenopericardial tube-grafts in 12 (21%), cryopreserved arterial/venous allografts in 9 (16%), and fresh arterial allografts in 5 (9%) patients. During a median follow-up of 26 months (range 3 weeks-172 months) there were no reinfections and only 3 patients (5%) required assistance with graft patency. Thirty-day survival was 95% (n=53) and 90-day survival was 91% (n=51). Treatment-related mortality was 9% (n=5). Kaplan-Meier estimation of survival at 1 year was 83% (95% confidence interval, 73%-94%) and at 5 years was 71% (52%-89%).

CONCLUSIONS

Mycotic abdominal aortic aneurysm repair with biological grafts is a durable option for patients fit for surgery presenting an excellent infection resistance and good overall survival.

Surgical Treatment of Native and Prosthetic Aortic Infection With Xenopericardial Tube Grafts

BACKGROUND

The study sought to report our results of surgical treatment of native and prosthetic aortic infection with xenopericardial tube grafts from the ascending aorta to beyond the bifurcation.

METHODS

Within a 28-month period, 20 patients were treated with a bovine self-made pericardial tube graft to replace infected vascular grafts (after conventional surgical aortic replacement or endovascular stent graft implantation) or to treat a contaminated surgical site. An integrated standardized therapeutic concept was applied in all patients, consisting of complete removal of the infected prosthetic material, extensive debridement, and orthotopic vascular reconstruction with self-made tube grafts constructed from a bovine pericardial patch.

RESULTS

Four patients died perioperatively (20%) due to sepsis, pulmonary failure, or sudden circulatory arrest. The mean follow-up was 18 months (first quartile 2, third quartile 17 months). Interval computed tomography scans revealed 100% freedom from proven aortic reinfection, but reinfection cannot be ruled out in 4 patients who died of unknown causes during follow-up or because of ongoing sepsis. Three patients required aortic reintervention for a suture-line aneurysm, for graft occlusion, and for the development of a neoaortointestinal fistulation, respectively.

CONCLUSIONS

Patients with infectious aortic disease present in a frail state and the initial and the late mortality is substantial. Yet, surgical treatment of native and prosthetic aortic infection with xenopericardial tube grafts shows promising short-term results with regard to durability and freedom from reinfection in any aortic segment. Further studies are needed to learn of the long-term behavior of these grafts.

Organization model for allotransplantations of cryopreserved vascular grafts in Czech Republic

The transplantation of fresh or cryopreserved vascular allografts in patients with a prosthetic graft infection or critical limb ischemia is necessary for their limb salvage and, in many cases, represents a lifesaving procedure. While transplantation of fresh allografts has a long history in the Czech Republic, the standard use of cryopreserved vascular allografts was introduced into the clinical practice in 2011 as a result of the implementation of EU Directive 2004/23/EC into national legislation (Human Cell and Tissue Act No. 296/2008 Coll.). The authors present an organizational model based on cooperation between the majority of Czech Transplant Centers with a tissue establishment licensed by the national competent authority. In various points, we are addressing individual aspects of experimental and clinical studies which affect clinical practice. Based on experimental and clinical work, the first validation of cryopreserved arterial and venous grafts for clinical use was performed between 2011 and 2013. The growing number of centers participating in this programme led to a growing number of patients who underwent transplantation of vascular allografts. In 2015 the numbers of transplanted fresh versus cryopreserved allografts in the Czech Republic were almost equal. Cooperation of the participating centers in the Czech Republic with the licensed Tissue Establishment made it possible to achieve a full compliance with the European Union Directives, and harmonized national legal norms and assured a high quality of cryopreserved vascular allografts.