A systematic review of infected descending thoracic aortic grafts and endografts

Physician Made Bovine Pericardial Tube Grafts in Aortic Infection: A European Multicentre Study

OBJECTIVE

This study examines outcome and durability of physician made bovine pericardial tube grafts in aortic infections in all anatomical locations.

METHODS

This was a retrospective and prospective international multicentre study. Peri-operative and long term outcomes of patients undergoing in situ aortic reconstruction for native or graft infections with physician made bovine pericardial tube grafts between January 2008 and December 2020 in four European tertiary referral centres were analysed. The primary endpoint was recurrent aortic infection. Secondary endpoints were persistent infection, aortic re-operation for infection, graft related complications, and death.

RESULTS

One hundred and sixty eight patients (77% male, mean age 67 ± 11 years) were identified: 38 (23%) with native and 130 (77%) with aortic graft infection. The thirty day mortality rate was 15% (n = 26) overall, 11% (n = 4), and 17% (n = 22) for native and aortic graft infections, respectively (p = .45). Median follow up was 26 months (interquartile range [IQR] 10, 51). Estimated survival at one, two, three, and five years was 64%, 60%, 57%, and 50%, and significantly better for native (81%, 77%, 77%, and 69%) than for graft infections (58%, 55%, 51%, and 44%; p = .011). Nine patients (5.3%) had persistent infection and 10 patients (6%) had aortic re-infection after a median of 10 months (IQR 5, 22), resulting in an estimated freedom from re-infection at one, two, three, and five years of 94%, 92%, 90%, and 86%. Estimated freedom from graft complications at one, two, three, and five years was 91%, 89%, 87%, and 87%.

CONCLUSION

This multicentre study demonstrates low re-infection rates when using physician made bovine pericardial tube grafts, comparable to those of other biological grafts. The rate of graft complications, mainly anastomotic aneurysms and stenoses, was low, while graft degeneration was absent. Physician made bovine pericardial tube grafts are an excellent tool for in situ reconstruction in the setting of native aortic infection or aortic graft infection.

Open repair with latissimus muscle flap coverage for treatment of infected thoracic endovascular aneurysm repair

A male patient, 70 years of age, was evaluated for an infected thoracic endovascular aneurysm repair (TEVAR). After presenting with persistent fever, a positron emission tomography scan found an infected aortic stent graft. The patient underwent open repair with explantation of the infected TEVAR, extensive periaortic debridement, graft replacement with a Dacron graft, and complete coverage with a latissimus dorsi muscle flap. Tissue culture revealed Clostridium spp. He was discharged home with long-term ampicillin and sulbactam. A postoperative computed tomography scan showed no recurrence of infection. Open surgery with latissimus muscle flap coverage is an achievable option for infected TEVAR.

Aortic Vascular Graft and Endograft Infection-Patient Outcome Cannot Be Determined Based on Pre-Operative Characteristics

Vascular graft/endograft infection (VGEI) is a serious complication after aortic surgery. This study investigates VGEI and patient characteristics, PET/CT quantification before surgical or conservative management of VGEI and post-intervention outcomes in order to identify patients who might benefit from such a procedure. PET standard uptake values (SUV) were quantitatively assessed and compared to a non-VGEI cohort. The primary endpoints were in-hospital mortality and aortic reintervention-free survival at six months. Ninety-three patients (75% male, 65 ± 10 years, 82% operated) were included. The initial operation was mainly for aneurysm (67.7%: 31% EVAR, 12% TEVAR, 57% open aortic repair). Thirty-two patients presented with fistulae. PET SUVTLR (target-to-liver ratio) showed 94% sensitivity and 89% specificity. Replacement included silver-coated Dacron (21.3%), pericardium (61.3%) and femoral vein (17.3%), yet the material did not influence the overall survival (p = 0.745). In-hospital mortality did not differ between operative and conservative treatment (19.7% vs. 17.6%, p = 0.84). At six months, 50% of the operated cohort survived without aortic reintervention. Short- and midterm morbidity and mortality remained high after aortic graft removal. Neither preoperative characteristics nor the material used for reconstruction influenced the overall survival, and, with limitations, both the in-hospital and midterm survival were similar between the surgically and conservatively managed patients.

Significance and current approaches to vascular graft infection

Vascular graft/endograft infection (VGEI) is a constant in cardiovascular surgery with published rates between 1 and 5%. Every graft type and anatomical location is a potential target for infectious complications. These patients are sick patients with high frailty burden. Management of VGEI entails a multidisciplinary and multimodality approach. Here we review some aspects of the problem of VGEI including prevention, diagnosis, and surgical therapy with focus on recent developments in the field.

Silver acetate and Triclosan Antimicrobial Graft Evaluation for surgical Repair of aortic disease (STAGER Study)

BACKGROUND

The aim of this study was to assess perioperative and late performance of a silver acetate and triclosan impregnated antimicrobial vascular graft (Intergard Synergy, Intervascular SAS, La Ciotat, France) during open surgical repair of abdominal aortic aneurysms (AAA), and to compare it with standard polyester grafts ones.

METHODS

This retrospective single-centre study (STAGER Study, clinicaltrials.gov: NCT04557254) included patients undergone non-infectious AAA surgical repair between 2012 and 2019, divided into two groups according to the implanted aortic prosthesis: standard polyester graft (PolyG) and silver-triclosan graft (SynG). Early primary endpoints were 30-day mortality, major adverse events (MAEs), and reintervention rates; late primary endpoints were overall and aortic-related survival, reintervention-free survival, and graft infection rate at a mean follow-up (FU) of 49.4±26.8 months.

RESULTS

Five hundred forty-seven patients were included [PolyG 49%, and SynG 51%]. Both groups were substantially homogeneous in risk factors and demographics. Two patients died within 30 days. In-hospital MAE rate [PolyG 14.2% vs. SynG 10.7%; P=.248] and 30-day reintervention rate were not significantly different [PolyG 2.6% vs. SynG 1.4%; P=.374]. At 5 years, overall survival in the PolyG and SynG groups were 85% and 84%, respectively. Reintervention-free survival was 82% for both groups. Aortic-related survival was 95% and 96%, respectively. Graft infection was observed in 8 (3.3%) PolyG patients and 5 (1.8%) SynG patients.

CONCLUSIONS

Silver acetate and triclosan impregnated grafts demonstrated good early and mid-term results, being considered safe and durable for AAA open repair. Similar graft infection and related death rates were observed compared to polyester standard grafts, supporting non-superiority of one graft over the other.

Secondary Endovascular Conversions for Failed Open Repair

Late aortic and graft-related complications after open aortic repair are not infrequent and a significant number of them are missed, diagnosed at a very late stage, or present as urgent complications such as aortic rupture or aorto-enteric fistula. Once a late complication is diagnosed and reintervention is necessary, both open and endovascular strategies are possible. Open reintervention is complex and usually associated with very high rates of morbidity and mortality. Endovascular techniques may offer several solutions for these cases, which may be tailored to the patient and specific complication. In this review, we aim to summarize current indications, options, and strategies for endovascular salvage after failed or complicated open surgical repair.

Conservative Management First Strategy in Aortic Vascular Graft and Endograft Infections

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Explant of the Aortic Endograft: Today's Solutions, Tomorrow's Problems

Type 2 endoleaks remain the Achilles heel of abdominal aortic endografting. They drive imaging costs and repeat intervention. We believe that after two endovascular interventions, patients should be considered for either graft explantation or graft salvage through an open abdominal exploration. Graft explantation has been associated with increased morbidity and mortality but remains necessary in the face of non-correctible type 1a endoleaks, graft failure, or graft infection. In the majority of cases AAA expansion due to persistent type 2 endoleak is the culprit. In this situation, open repair, with oversewing of the lumbar or inferior mesenteric arteries, can be accomplished providing the seal zones and component overall zones are adequate. This approach does not require aortic clamping. We provide detailed descriptions and videos to facilitate the surgeon in performing these complex procedures.

Thoracic aortic vascular graft infection: outcome after conservative treatment without graft removal

OBJECTIVES

Surgical debridement with aortic graft removal is considered the preferred treatment for thoracic aortic vascular graft infection (VGI). Conservative treatment with antibiotics only is usually reserved for inoperable patients. Due to Outpatient Parenteral Antimicrobial Therapy (OPAT) and better understanding of the antibiotic impact on biofilms, long-term targeted antibiotic therapy without graft removal may be an alternative treatment option for selected thoracic aortic VGI patients. The aim of this case series was to evaluate the outcome in patients with thoracic aortic VGI who were treated without graft removal.

METHODS

This single-centre retrospective cohort study evaluated patients with a thoracic aortic VGI diagnosed between 2008 and 2021 and who were treated without graft removal. The primary outcome parameter was the 6-month mortality rate after VGI diagnosis. Secondary outcome parameters were cure rates and relapse of infection.

RESULTS

Twenty-four patients with thoracic aortic VGI who were managed without graft removal were identified. The mortality rate 6 months after VGI diagnosis was 8% (2/24); one of these deaths was infection related. The median antibiotic treatment duration was 13 months (interquartile range 15). A total of 16 patients (67%) were cured. No relapses occurred after a median of 24-month (interquartile range 32) follow-up.

CONCLUSIONS

Intensive antibiotic treatment, without graft removal, may be a non-inferior option in patients with a thoracic aortic VGI who are not considered for surgery.

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.

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

Purpose

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

Methods

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

Results

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

Conclusion

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

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

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

Patient-tailored approach for diagnostics and treatment of mycotic abdominal aortic aneurysm

OBJECTIVE

The existing literature on mycotic aortic aneurysm is scarce and focuses on treatment. This study evaluates the clinical characteristics, diagnostics, treatment and outcome of patients with a mycotic abdominal aortic aneurysm treated in a tertiary referral center.

METHODS

A retrospective cohort study was conducted including all patients with a proven mycotic abdominal aortic aneurysm admitted between May 2010 and July 2020. Primary outcome was mortality and secondary outcome included complications such as vascular graft/endograft infection.

RESULTS

Twenty-four patients with a mycotic abdominal aortic aneurysm were included. Patients had a mean age of 68 ± 9 years and 20 (83%) were male. Thirteen patients (57%) had positive preoperative blood cultures. Streptococcus pneumoniae was most frequently isolated by blood culturing, pus, and vascular or perivascular tissue cultures (17%). In 19 (83%) patients the mycotic abdominal aortic aneurysm was located infrarenally, in three (13%) patients suprarenally, and in one (4%) patient juxtarenally. Median follow-up was 20 (7-42) months. In eight patients (33%) vascular graft and or endograft infection was diagnosed after surgical repair. Ten (42%) patients died during the follow-up period. The main causes of death were vascular graft/endograft infection-related (n=4) and rupture of the mycotic abdominal aortic aneurysm (n=3). No patient characteristics could be identified as predictive for mortality.

CONCLUSION

This study shows a large variation in presentation, diagnostic approaches, and surgical and antibiotic treatment of mycotic abdominal aortic aneurysm. The detailed information about the diagnostic approaches to this rare disease and its antibiotic/other treatment contributes to existing knowledge of mycotic abdominal aortic aneurysm. Because of the individual variation patients should be discussed in a multidisciplinary team with a vascular surgeon, infectious disease specialist, and clinical microbiologist.

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.

The impact of vascularized tissue flap coverage on aortic graft infection with and without infected graft excision

OBJECTIVES

Aortic graft infection (AGI) is a serious condition associated with a high mortality rate. However, optimal surgical options have not been identified. Therefore, we retrospectively reviewed AGI cases, including those in the thoracic and abdominal regions, with or without fistula formation, to investigate the various options for better outcomes.

METHODS

We reviewed 50 patients who underwent surgical interventions for AGI out of 97 patients with arterial infective disease. The mean patient age was 67 ± 17 years. Fourteen patients (28%) had a fistula with the gastrointestinal tract or lung. A combination of graft excision and vascularized tissue flap coverage was performed in 25 cases (50%). Tissue flap alone, graft excision alone and cleansing alone were performed in 9 (18%), 10 (20%), and 6 cases (12%), respectively.

RESULTS

Total in-hospital mortality rate was 32% (n = 16). In-hospital mortalities in patients with and without fistulas were 43% (6/14) and 28% (10/36), respectively (P = 0.33). Subgroup analysis among patients without fistula demonstrated that the in-hospital mortality rate of the patients with vascularized tissue flap (3/21, 14%) was significantly lower than that of the patients without vascularized tissue flap (7/14, 50%, P = 0.026). Overall 1- and 5-year survival rates were 66% and 46%, respectively. In multivariable analysis, an independent factor associated with in-hospital mortality was vascularized tissue flap (odds ratio 0.20, P = 0.024).

CONCLUSIONS

Vascularized tissue flaps could provide better outcomes for AGI. Graft preservation with vascularized tissue flaps could be a useful option for AGI without fistula.

Native and prosthetic graft infections of the thoracic aorta: surgical management

 

OBJECTIVES

Infection of the native aorta or after previous open or endovascular repair of the thoracic aorta is associated with high risks for morbidity and mortality. We analysed the outcome after surgical management of a native mycotic aneurysm or of prosthetic graft infection of the descending aorta.

METHODS

From June 2000 to May 2019, a total of 39 patients underwent surgery in our centre for infection of the native descending aorta (n = 19 [49%], group A) or a prosthetic descending aorta [n = 20 (51%), group B]. In the 20 patients in group B, a total of 8 patients had prior open aortic repair with a prosthesis and 12 patients had a previous endovascular graft repair.

RESULTS

The cohort patients had a mean age of 57 ± 14; 62% were men (n = 24). The most common symptoms at the time of presentation included fever, thoracic or abdominal pain and active bleeding. Emergency surgery was performed in 11 patients (28%); 3 patients had emergency endovascular stent grafts implanted during thoracic endovascular aortic repair for aortic rupture before further open repair. The 30-day mortality was 42% in group A and 35% in group B. The 90-day mortality was 47% in group A and 45% in group B. Pathogens could be identified in approximately half of the patients (46%). The most commonly identified pathogens were Staphylococcus aureus in 6 patients (15%) and Staphylococcus epidermidis in 4 patients (10%). Survival of the entire group (including patients with both native and prosthetic graft infections) was 44 ± 8%, 39 ± 8% and 39 ± 8% at 1, 2 and 3 years after surgery. The percentage of patients who survived the initial perioperative period was 81 ± 9%, 71 ± 9% and 71 ± 10% at 1, 2 and 3 years after surgery.

CONCLUSIONS

Patients with infection of the descending aorta, either native or prosthetic, are associated with both high morbidity and mortality. However, patients who survive the initial perioperative period have an acceptable long-term prognosis. In emergency situations, thoracic endovascular aortic repair may help to stabilize patients and serve as bridge to open repair.

A rare case of an infected aortoiliac graft complicated with Eggerthella lenta bacteremia and septic shock

We describe the successful medical management of an infected aorto-bi-Iliac endograft. In this case report, we provide an example of a patient with an infected aorto-bi-iliac endograft and how appropriate medical management may result in a positive outcome. We report a case of a 67-year-old man with several medical comorbidities who developed aorto-bi-iliac endograft infection one year after graft placement. The patient presented to our E.R. with fever, lethargy, tachycardia, tachypnea, and hypotension. The diagnosis of an infected endograft was established after excluding any other possible source of infection plus the strong radiological evidence by computed tomographic scan and WBCs labeled Indium-111 tropolone scan. Blood cultures revealed the development of Eggerthella lenta, Escherichia coli Extended-spectrum beta-lactamase (ESBL), and Enterococcus Faecalis. To our knowledge, this is a rare case of an infected endograft and bacteremia due to Eggerthella lenta. After the administration of vancomycin and Meropenem, no improvements were noted to the patient’s clinical condition. However, upon the administration of Tigecycline, the patient’s clinical condition improved. Two days later, repeat blood cultures were negative.

After completion of the course of antibiotics and stabilization of other comorbidities, the patient was discharged home with long term antibiotic therapy under close control of inflammation markers.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Management of Vascular Infections in Low- and Middle-Income Countries

Background: Vascular infections are rare and challenging conditions with significant deaths and morbidity. Their management necessitates a multi-disciplinary approach and substantial human and financial resources. The management selected may be influenced by the available resources in low- and middle-income countries (LMICs), where such resources may be variable. Methods: We reviewed the published literature and reviewed the management options for various vascular infections with a focus on carotid, aortic, infrainguinal, and dialysis access infections. Results: Recommendations related to prevention and treatment will be offered from the perspective of LMICs. The general principles for prevention are in compliance with established surgical site infection guidelines and minimize the use of prosthetic material. Early detection and intervention by removing all infected prosthetic material, debridement, drainage, and coverage of the infected field with vascularized tissue are essential steps in the management of the infection. Revascularization using an extra-anatomic or in situ approach is individualized based on the resources and expertise available. Conclusions: The prevention and management of vascular infections in LMICs are effective by adhering to time-proven principles even with limited resources.

Explantation of an Infected TEVAR With an Extra-Anatomic Arch Reconstruction Along the Right Heart

This case represents the disease progression and workup of an infected thoracic endovascular aortic repair (TEVAR) graft that initially manifested as an aortic arch pseudoaneurysm. The patient underwent a 2-stage operation to resect the infected TEVAR and to reconstruct flow via an extra-anatomic aortic bypass paralleling the right heart. This is one of the few documented cases of TEVAR explantation with an extra-anatomic aortic bypass to re-establish flow.