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

Two-Decade Single-Center Experience with Graft Infections After Infrarenal Endovascular Aortic Repair

BACKGROUND

To study the incidence of endovascular aneurysm repair (EVAR) graft infections and to examine the results of treatment at a single institution, where the mainstay of treatment has for 20 years been to explant the infected grafts and to reconstruct in situ with biological materials.

METHODS

All standard EVAR patients treated from January 2000 to December 2022 at our institution were extracted from a prospective vascular surgery database, and post-EVAR infections were identified through a chart review and analyzed retrospectively. Primary endpoints were short-term (30-day and 90-day) mortality and mid-term survival. Secondary endpoints were freedom from reinfections and freedom from reinterventions.

RESULTS

A total of 29 EVAR grafts in 1,274 patients became infected during a mean total follow-up of 6.36 years (range 4.4 months-23.3 years). The cumulative rate of infections was 1.7%, and the incidence rate was 2.69 cases per 1,000 patient-years in the patient group where the primary EVAR was performed in an elective setting. The median time to infection was 8.4 months (range: 9 days-11.4 years). With 3 additional patients from other institutions, a total of 32 patients underwent treatment for an EVAR graft infection. Only 2 patients (6.3%) were female. Nine patients (28.1%) were treated conservatively, 1 patient was operated with a graft preservation strategy and the rest (n = 22, 69%) underwent graft explantation and in situ reconstruction. In these 22 reconstructions, the graft material used was an autologous femoral vein in 19 (86.4%) patients, a cryopreserved allogenous femoral vein in 2 (9.1%) patients, and a rifampicin-soaked dacron prosthesis in 1 (4.5%) patient. The early postoperative mortality was 19.0% (n = 4 of 21) at 30 days and 23.8% (n = 5 of 21) at 90 days for the patients with explanted grafts with in-situ reconstruction, while survival at 1 year was 76.2% (n = 16 of 21) for the group treated with biological reconstruction and 44.4% (n = 4 of 9) for the conservatively treated patients. Similarly, in Kaplan-Meier analysis, the 3-year survival was 68.2% and 22.2%, respectively (P = 0.002). During a median follow-up of 2.3 years (range: 3 days-12.4 years), there were no reinfections among patients with biological reconstructions, and none of the patients required late graft reinterventions.

CONCLUSION

EVAR graft explantation and in situ biological aortic reconstruction offers a viable, infection-resistant and durable solution for the treatment of EVAR infection.

Contemporary outcomes for arterial reconstruction with non-saphenous vein cryo-preserved conduits

OBJECTIVE

Cryopreserved (CP) products are utilized during challenging cases when autogenous or prosthetic conduit use is not feasible. Despite decades of experience with cadaveric greater saphenous vein (GSV), there is limited available data regarding the outcomes and patency of other CP products, specifically arterial and deep venous grafts. This study was designed to evaluate outcomes of non-GSV CP conduits in patients undergoing urgent, emergent, and elective arterial reconstruction at our institution. We hypothesized that non-GSV CP allografts have adequate patency and outcomes and are therefore a feasible alternative to GSV in settings where autologous graft is unavailable or prosthetic grafts are contraindicated.

METHODS

This study was approved by the Institutional Review Board at our institution. We retrospectively reviewed charts of patients undergoing arterial reconstructions using CP conduits from 2010 to 2022. Data collected included demographics, comorbidities, smoking status, indications for surgery, indication for CP conduit use, anatomic reconstruction, urgency of procedure, and blood loss. Time-to-event outcomes included primary and secondary graft patency rates, follow-up amputations, and mortality; other complications included follow-up infection/reinfection and 30-day complications, including return to the operating room and perioperative mortality. Time-to-event analyses were evaluated using product-limit survival estimates.

RESULTS

Of 96 identified patients receiving CP conduits, 56 patients received non-GSV conduits for 66 arterial reconstructions. The most common type of non-GSV CP product used was femoral artery (31 patients), followed by aorto-iliac artery (22 patients), and femoral vein (19 patients), with some patients receiving more than one reconstruction or CP product. Patients were mostly male (75%), with a mean age of 63.1 years and a mean body mass index of 26.7 kg/m2. Indications for CP conduit use included infection in 53 patients, hostile environment in 36 patients, contaminated field in 30 patients, tissue coverage concerns in 30 patients, inadequate conduit in nine patients, and patient preference in one patient. Notably, multiple patients had more than one indication. Most surgeries (95%) were performed in urgent or emergent settings. Supra-inguinal reconstructions were most common (53%), followed by extra-anatomic bypasses (47%). Thirty-day mortality occurred in 10 patients (19%). Fifteen patients (27%) required return to the operating room for indications related to the vascular reconstructions, with 10 (18%) cases being unplanned and five (9%) cases planned/staged. Overall survival at 6, 12, and 24 months was 80%, 68%, and 59%, respectively. Primary patency at 6, 12, and 24 months was 86%, 70%, and 62%, respectively. Amputation freedom at 6 months, 12 months, and 24 months was 98%, 95%, and 86%, respectively for non-traumatic indications.

CONCLUSIONS

Non-GSV CP products may be used in complex arterial reconstructions when autogenous or prosthetic options are not feasible or available.

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.

Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms

OBJECTIVE

The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy.

METHODS

The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence.

RESULTS

A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed.

CONCLUSION

The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

Performance of the BioIntegral Bovine Pericardial Graft in Vascular Infections: VASCular No-REact Graft Against INfection Study

BACKGROUND

Vascular graft and endograft infections (VGEI) and native vessel infections (NVI) remain considerable challenges in vascular surgery, leading to high mortality and morbidity rates. Although in situ reconstruction is the preferred treatment, the material of choice is still a source of debate. Autologous veins are considered the first choice; however, xenografts may be an acceptable alternative. The performance of a biomodified bovine pericardial graft is assessed when implemented in an infected vascular area.

METHODS

This is a prospective multicenter cohort study. Patients who underwent reconstruction for VGEI or NVI with a biomodified bovine pericardial bifurcated or straight tube graft were included from December 2017 until June 2021. The primary outcome measure was reinfection at mid-term follow-up. Secondary outcome measures included mortality, patency, and amputation rate.

RESULTS

Thirty-four patients with vascular infections were included, of which 23 (68%) had an infected Dacron prosthesis after primary open repair and 8 (24%) had an infected endovascular graft. The remaining 3 (9%) had infected native vessels. At secondary repair, 3 (7%) patients had an in situ aortic tube reconstruction, 29 (66%) had an aortic bifurcated reconstruction, and 2 (5%) had an iliac-femoral reconstruction. At 1-year follow-up after the BioIntegral bovine pericardial graft reconstruction, the reinfection rate was 9%. The 1-year infection-related and procedure-related mortality rate was 16%. The occlusion rate was 6% and in total 3 patients underwent a lower limb amputation during the 1-year follow-up period.

CONCLUSIONS

In situ reconstruction as treatment of (endo)graft and native vessel infections remains a challenge and reinfection looms as a potential consequence. In cases where time is of essence or when autologous venous repair is not feasible, a swift available solution is needed. The BioIntegral biomodified bovine pericardial graft may be an option as it shows reasonable results in terms of reinfection, in aortic tube and bifurcated grafts.

Biological autologous excised varicose vein dressing compared to conservative dressing on the ulcer bed during endovenous ablation

Objective

To compare the use of biological autologous excised varicose vein dressing ( VenoDress) compared to conservative dressing on the ulcer bed during endovenous ablation

Methods

This retrospective non-blinded study included all consecutive patients with primary or recurrent venous leg ulcers (VLU) with superficial varices treated in one center between September 2019 and October 2020. They all underwent venous ablation, wound debridement, and when needed phlebectomy. On the study group, the excised veins were incised, formed into a sheet, and applied onto the debrided wound bed with the endothelial side facing the wound bed. Adhesion was assessed weekly for 3 weeks. The study group was compared to a control group that underwent similar procedures but with the debrided wound bed treated with low-adherent paraffin dressing. The primary outcome was complete wound healing at 1 and 3 months, and the secondary outcomes were wound-related pain and leg edema.

Results

Complete wound closure was documented in 17/26 study group patients at 1 month (65%) and in 25/26 (96%) at 3 months. Complete wound closure was documented in 37/82 patients in the control group (45%) and in 67/82 (82%) at 3 months. The 1-month healing rates were significantly in favor of the VenoDress group when adjusted to sex and diabetes: odds ratio = 2.81 (1.05–7.532), p = .04. The preoperative pain level of the study group (as measured by a visual analog scale VAS (0–10) decreased from 4.96 ± 2.71 to 0.73 ± 1.36 at 1 week and that of the control group from 4.8 ± 2 to 1.35 ± 1.38 at 1 week ( p < .001).

Conclusion

the use of autologous varicose veins as dressing effectively reduced pain in VLU patients compared to conventional techniques. Although its effects on wound closure appear highly promising, further validation is warranted in a randomized comparative study.

Potentials of Using Allografts in Surgical Treatment of Popliteal Artery Aneurysms

BACKGROUND: The gold standard in reconstructive surgical operations on the infrainguinal arteries is the autovenous conduit from the great saphenous vein. However, in the absence of a suitable autovein, difficulties are encountered in the selection of a suitable material for reconstruction. The use of a synthetic prosthesis as an alternative in the knee joint region is not always possible, especially in the distal position. Unsatisfactory results of using such materials dictate the need to choose a suitable graft. The paper describes two case experiences of using allografts from a deceased donor for the surgical treatment of popliteal artery aneurysms. The cases present their potential for use in emergency clinical situations. In the first case, the patient had previously undergone phlebectomy. In the second case, the saphenous veins of the lower limbs had scattered branches and insufficient diameter for reconstruction. CONCLUSION: The described cases presented the possible effective use of allografts from a deceased donor in patients with true popliteal artery aneurysms.

Cryopreserved venous allograft in the treatment of a mycotic abdominal aortic aneurysm caused by group B Streptococcus

We report a case of a mycotic abdominal aortic aneurysm caused by invasive group B streptococcus. Given the anatomical suitability with healthy segments of aortoiliac vessels, in situ repair was performed. A cryopreserved femoral vein graft was chosen because of risks of graft reinfection and negated the need for bilateral femoral vein harvest. The patient remained clinically well and the graft patent with no concerns at 6 months of follow-up. A review of literature on group B Streptococcus aortitis was performed.

Contemporary management of infective native aortic aneurysms

PURPOSE OF REVIEW

Infective native aortic aneurysms (INAAs) are challenging and complex with both bacteraemia and an aneurysm prone to rupture. They are fatal unless recognized and treated promptly. The rarity of the disease makes it unfamiliar to most physicians, which might delay both diagnosis and treatment.The present review aims to outline the recently published diagnostic algorithm of INAAs, the main characteristics of the disease and present an overview of contemporary treatment strategies.

RECENT FINDINGS

New terminology, definition, diagnostic algorithm and reporting standards have recently been proposed for INAAs. Current evidence concerning the treatment of INAAs is founded on retrospective register-based multicentre studies and small single-centre studies. Recent findings encourage the use of endovascular aortic repair (EVAR) for surgical treatment of INAAs. Although EVAR, as a surgical approach, does not drain the infection, the postoperative infection-related complication rates (IRCs) are similar to the ones reported after open surgical repair (OSR) with aortic prosthetic reconstruction and extensive debridement. IRCs carry over 50% risk of being fatal. Postoperative mortality after EVAR remains considerably lower supporting the use of method for aged and comorbid group of patients. Biological grafts have the benefit of being more resistant to reinfection. OSR with biological reconstruction is a promising surgical approach for patients fit for open surgery; however, data are scarce and long-term follow-up is lacking.

SUMMARY

The treatment of INAAs should be guided by experienced multidisciplinary team and tailored individually based on patients' condition and centres' experience. An international consensus document is warranted to enable further research on this disease.

Deep Femoral Vein Reconstruction for Abdominal Aortic Graft Infections is Associated with Low Aneurysm Related Mortality and a High Rate of Permanent Discontinuation of Antimicrobial Treatment

OBJECTIVE

Aortic prosthesis infection is a devastating complication of aortic surgery. In situ reconstruction with the neo-aorto-iliac system (NAIS) bypass technique has become increasingly used and is recommended in recent treatment guidelines. The main aim was to evaluate NAIS procedural outcomes when undertaken after previous open or endovascular aortic repair in Sweden.

METHODS

In this retrospective study, The National Quality Registry for Vascular Surgery (Swedvasc) was used to identify Swedish centres that offered the NAIS bypass procedure for aortic prosthesis infection between 2008 and 2018. Variables of special interest were procedural details, short and long term survival, renal and other complications, and the durtion of antimicrobial treatment.

RESULTS

Forty patients (36 males, four females [mean age 69 years], 32 open repairs, seven endovascular aortic repairs [EVAR] and one fenestrated EVAR; 21 presented with aorto-enteric fistula) operated on with NAIS bypass were reviewed. The median time from the primary aortic intervention to the NAIS bypass procedure was 32 months (range 0 - 252 months). Mean ± standard deviation operating time was 645 ± 160 minutes, mean blood loss was 6 277 ± 6 525 mL, mean length of intensive care unit stay was 5.3 ± 3.7 days, and mean length of overall hospital stay was 21.2 ± 11.4 days. Thirty-five patients (88%) had a positive microbial culture; the most commonly isolated pathogen was Candida spp. The majority of patients survived for 30 days (n = 35 [88%]), and 33 (83%) and 32 (80%) patients survived for 90 days and one year, respectively. The number of surviving patients free from antimicrobial treatment at 90 days, six months, and one year was 19 (58%), 29 (88%), and 30 (94%). After a mean long term follow up of 69.9 ± 44.7 months, 20 patients were still alive.

CONCLUSION

The NAIS bypass procedure offered reasonable survival and functional outcomes, and was associated with a high cure rate, defined as freedom from any antimicrobial treatment.