Outcomes of complex femorodistal sequential autologous vein and biologic prosthesis composite bypass grafts

[Surgical therapy of peripheral arterial occlusive disease]

The surgical treatment of peripheral arterial occlusive disease focuses not only on the direct restoration of the femoral bifurcation but also on the peripheral bypass, especially in the case of chronic amputation-threatening ischemia. Comprehensive imaging is indispensable for planning surgical therapy. The local reconstruction of the femoral bifurcation offers very good long-term results and can be easily combined with endovascular methods. The peripheral bypass is the central pillar of surgical therapy, especially in CLTI. Autologous vein should always be the first-choice material. It delivers good long-term results in every position. Prosthetic material is only used if there is no vein and should be combined with autologous veins in the crural and pedal area if possible. The technical limit for a bypass system lies in the pedal arteries and their branches. These methods can be combined with upstream and downstream endovascular interventions in the form of a hybrid intervention. Surgical and endovascular interventions are to be considered as complementary.

Long-Term Results of Femorodistal Sequential Composite-Bypass Combining Heparin-Bonded PTFE-Prosthesis and Autologous Vein Using the Deutsch Bridge Technique in Critical Limb-Threatening Ischemia

BACKGROUND

Autologous vein bypass provides excellent long-term results in critical limb-threatening ischemia (CLTI), but a substantial portion of patients have insufficient vein length. In limbs with two distal outflow vessels and limited vein length, a vascular prosthesis may be combined with autologous vein for a sequential composite bridge bypass (SCBB). Results regarding graft function, limb salvage and reinterventions are presented.

METHODS

Between January 2010 and December 2019, 47 consecutive SCBB operations with a heparin-bonded PTFE-prosthesis and autologous vein were performed. Grafts were followed with a duplex scan with prospective documentation in a computerized vascular database. Retrospective analysis of graft patency, limb salvage and patient survival was performed.

RESULTS

Mean follow-up was 34 months (range 1-127 months). 30-day mortality was 10.6% and 5-year patient survival 32%. Postoperative bypass occlusion occurred in 6.4% and late occlusions or graft stenoses in 30%. Two prostheses developed late infection and seven legs were amputated. Primary, primary assisted, secondary patency and limb salvage rate were 54%, 63%, 66% and 85% after 5 years, respectively.

CONCLUSIONS

SCBB patency and limb salvage were good despite a high early postoperative mortality. Combination of a heparin-bonded PTFE-prosthesis and autologous vein appears to be a valuable tool in CLTI in case of insufficient vein.

Acellular Human Placenta Small-Diameter Vessels as a Favorable Source of Super-Microsurgical Vascular Replacements: A Proof of Concept

In this study, we aimed to evaluate the human placenta as a source of blood vessels that can be harvested for vascular graft fabrication in the submillimeter range. Our approach included graft modification to prevent thrombotic events. Submillimeter arterial grafts harvested from the human placenta were decellularized and chemically crosslinked to heparin. Graft performance was evaluated using a microsurgical arteriovenous loop (AVL) model in Lewis rats. Specimens were evaluated through hematoxylin-eosin and CD31 staining of histological sections to analyze host cell immigration and vascular remodeling. Graft patency was determined 3 weeks after implantation using a vascular patency test, histology, and micro-computed tomography. A total of 14 human placenta submillimeter vessel grafts were successfully decellularized and implanted into AVLs in rats. An appropriate inner diameter to graft length ratio of 0.81 ± 0.16 mm to 7.72 ± 3.20 mm was achieved in all animals. Grafts were left in situ for a mean of 24 ± 4 days. Decellularized human placental grafts had an overall patency rate of 71% and elicited no apparent immunological responses. Histological staining revealed host cell immigration into the graft and re-endothelialization of the vessel luminal surface. This study demonstrates that decellularized vascular grafts from the human placenta have the potential to serve as super-microsurgical vascular replacements.

Ovine Biosynthetic Grafts for Aortoiliac Reconstructions in Nonsterile Operative Fields

BACKGROUND

Prosthetic vascular grafts placed surgically or via endovascular techniques can be subject to the risk of life-threatening graft infections. The Omniflow II vascular prosthesis is a biosynthetic graft that was reported to have favorable properties in resisting infections.

MATERIALS AND METHODS

We retrospectively reviewed our 3 years' experience of using the Omniflow II prostheses for aortoiliac reconstructions in patients considered to carry a substantial risk of subsequent prosthetic graft infections (prevention group) as well as in patients with actively infected prosthetic vascular grafts (treatment group).

RESULTS

Aorto-bi-iliac (n = 4) and aortobifemoral (n = 12) vascular reconstructions were performed using bifurcated Omniflow II prostheses in nine patients in the prevention group and seven patients in the treatment group. During mean follow-up of 28.6 ± 17.2 months, there was one case of graft infection (6.3%) and graft thrombosis (6.3%) with subsequent successful thrombectomy. Early and late surgical revisions were required in eight (50%) and two (12.6%) patients, respectively. All graft prostheses were patent at last follow-up.

CONCLUSION

Using bifurcated Omniflow II vascular prostheses in patients with or at a high risk of vascular graft infection is advisable, and is associated with acceptable reinfection and patency rates.

Alternative autologous and biologic conduits have worse outcomes than prosthetic grafts for infrainguinal bypass in patients with chronic limb-threatening ischemia

OBJECTIVE

Single segment great saphenous vein (GSV) is the preferred conduit in infrainguinal bypass. Alternative autologous conduits (AAC) and nonautologous biologic conduits (NABC) are thought to be a better alternative to traditional prosthetic conduits (PC) in the absence of GSV. In this study we analyzed the outcomes of these alternative conduits in lower extremity bypasses (LEB) in patients with chronic limb-threatening ischemia.

METHODS

The Vascular Quality Initiative LEB database from 2003 to 2020 was queried for this study, to identify LEB in patients with chronic limb-threatening ischemia. Primary outcomes were graft patency, major adverse limb events (MALE), and MALE-free survival at 1 year. Standard statistical methods were used as appropriate.

RESULTS

We identified 22,671 LEB procedures (12,810 GSV, 6002 PC, 1907 AAC, and 1952 NABC). Compared with the GSV group, the other conduit patients were significantly older, had more comorbidities, had an increased rate of prior lower extremity interventions, had a higher rate of infrageniculate bypass targets, and were less ambulatory at baseline. The PC, AAC, and NABC groups had significantly higher rates of postoperative morbidity compared with the GSV group. The PC group had a higher 30-day mortality compared with the GSV, AAC, and NABC groups (3% PC vs 2% GSV, 2% AAC, 2% NABC; P = .049). Both PC and NABC had higher 1-year mortality compared with GSV and AAC (13% PC and 13% NABC vs 10% GSV, 10% AAC; P = .02). In an adjusted Cox regression model (stratified by infrageniculate target and adjusted for age, comorbidities, and prior vascular interventions) PC was not significantly different from GSV, but AAC (hazard ratio [HR], 1.41; 95% confidence interval [CI], 1.19-1.67; P < .001) and NABC (HR, 1.9; 95% CI, 1.61-2.25; P < .001) were associated with an increased risk of loss of primary patency. A similar association with MALE was observed: both AAC (HR, 1.35; 95% CI, 1.15-1.58; P < .001) and NABC (HR, 1.8; 95% CI, 1.53-2.11; P < .001) were associated with an increased risk of MALE compared with GSV; PC was not significantly different from GSV.

CONCLUSIONS

In the absence of GSV, alternative conduits (autologous or nonautologous biologic) do not confer a benefit with regard to graft patency or MALE compared with PCs. Increased operating time or costs associated with the use of these conduits is not justified based on this study.

The Role of Early Revascularization and Biomarkers in the Management of Diabetic Foot Ulcers: A Single Center Experience

Diabetic neuropathy and Peripheral Arterial Disease (PAD) are the main etiological factors in foot ulceration. Herein, we report our experience of diabetic foot ulceration (DFU) management, with an analysis of the relationship between the rate of lower extremity amputation, in persons with infected DFU, after revascularization procedures performed to prevent major amputation. This study highlights the role of different biomarkers, showing their usefulness and potentiality in diabetic foot ulcer management, especially for the early diagnosis and therapy effectiveness monitoring. A retrospective analysis, from September 2016 to January 2021, of diabetic patients presenting diabetic foot with DFU, was performed. All patients were treated with at least one vascular procedure (endovascular, open, hybrid procedures) targeting PAD lesions. Outcomes measured were perioperative mortality and morbidity. Freedom from occlusion, primary and secondary patency, and amputation rate were registered. A total of 267 patients, with a mean age of 72.5 years, were included in the study. The major amputation rate was 6.2%, minor amputation rate was 17%. In our experience, extreme revascularization to obtain direct flow reduced the rate of amputations, with an increase in ulcer healing.

Composite femoro-tibial bypass as alternative solution in complicated revascolarization: Case report

Introduction

Peripheral Arterial Disease (PAD) in diabetic patients is a significant cause of Morbility. Long arterial occlusion in patient previously treated can require unusual and complex solution. Herein we report a case of complicated bypass in diabetic patient with history of bypass for bilateral popliteal aneurysm.

Presentation of case

A 51-year-old male, smoker, with hypertension and diabetes mellitus was referred to our hospital for rest pain in left limb and peripheral cyanosis. Ultrasound doppler (US) showed an occlusion after common femoral artery with patency of Anterior-tibial artery (ATA) two centimeters after the origin. The unavailability of adequate autologous conduit necessitated an alternative solution and was chosen a composite femoro-anterior tibial artery bypass with successive ATA angioplasty to ensure the patency of graft.

Discussion

The autogenous vein is the preferred conduit in below-knee vascular reconstructions but in redo-procedures in the absence of vein, synthetic or biologic vascular prostheses must be considered as graft material. In these cases tibial angioplasty can improve the outflow and the patency.

Conclusion

Composite Femoro-ATA bypass with tibial angioplasty is an alternative technique for critically ischemic legs with limited autologous vein material. In our experience this approach was safe and effective.

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Damage of microcirculation can be due to major amputation with an incidence of 30.7%.

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Long arterial occlusion in patient previously treated can require complex solution.

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In this case we have chosen a composite femoro-anterior tibial artery bypass.

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Composite Fem-ATA bypass with tibial angioplasty is an alternative technique in CLI.

Outcomes of biosynthetic vascular graft for infrainguinal femoro-popliteal and femoro-distal revascularization

BACKGROUND

The aim of this study was to retrospectively analyze early and late outcomes of infrainguinal revascularization performed with the Omniflow-II^® (LeMaitre Vascular, Inc., Burlington, MA, USA) biosynthetic vascular graft (BVG) for complex femoro-popliteal obstructive disease.

METHODS

Over a 10-year period, this BVG was used in 110 patients who underwent infrainguinal femoro-popliteal or femoro-distal bypass. Early (intraoperative and <30 days) results were analyzed in terms of death, thrombosis, amputations and reinterventions. Follow-up results were analyzed in terms of primary and secondary graft patency, and amputation-free survival.

RESULTS

We performed 87 (79.1%) above-the-knee bypass, 20 (18.2%) below-the-knee bypass, and 3 (2.7%) tibial artery bypass. In-hospital mortality was not observed. Mean follow-up was 66±37 months (range, 3-150). Estimated primary patency rate at 1, 2 and 5-years of follow-up was 77%±4 (95%CI: 68-84), 73%±5 (95%CI: 63.5-83), and 59%±6 (95%CI: 47-70.5) respectively. Predictors of primary patency loss were the presence of critical limb ischemia (P=0.048; HR: 2.1; 95%CI: 1.01-4.28), and the necessity of below-the-knee bypass (P=0.012; HR: 2.4; 95%CI: 1.22-4.75). Aneurysmal degeneration of the BVG was detected in 4 (3.6%) patients, an infected BVG occurred in 3 (2.7%) patients. The amputation-free survival was 96%±2 (95%CI: 91-99), 93%±3 (95%CI: 86-96), and 76%±5 (95%CI: 66-84) at 1, 2 and 5-years respectively.

CONCLUSIONS

In our experience, Omniflow-II^® is a valid first-line alternative for infrainguinal revascularization when the ipsilateral autologous saphenous vein is not available. Aneurysmal degeneration was lower than previously reported with alternative BVGs, and the incidence of BVG infection was acceptably low.

Late hematogenous seeding and infection of a femoropopliteal Omniflow II bypass

INTRODUCTION

Omniflow II is promoted as an infection-resistant vascular graft. It is used to treat vascular graft infection; nevertheless, early graft infection has been reported.Report: A 71-year-old patient was treated with an Omniflow II bypass for a non-healing diabetic foot ulcer. Seven months postoperatively, late infection occurred secondary to hematogenous spread from a persistent foot infection.

CONCLUSION

We report on the first case of late infection of an Omniflow II vascular graft caused by hematogenous spread. Despite promising results of the Omniflow II graft in the treatment of vascular graft infection, late infection may not be avoided.

How to manage patients with polyvascular atherosclerotic disease. Position paper of the International Union of Angiology

Atherosclerosis is a systemic disease affecting multiple arterial territories. Patients with clinical atherosclerotic disease in one vascular bed are likely to have asymptomatic or symptomatic atherosclerotic lesions in other vascular beds. Specifically, peripheral arterial disease (PAD) often coexists with coronary and carotid disease. With progression of atherosclerotic disease in one vascular bed, the risk of clinical manifestations in other territories increases and the incidence of adverse cardiovascular events increases substantially with the number of affected vascular beds. Classical risk factors are associated with the development of polyvascular atherosclerotic disease (PVD) in different territories; however, to a different extent. Risk modification represents basic treatment of patients with PVD. All modifiable risk factors should be aggressively controlled by lifestyle modification and medication. Particular attention should be directed to patients with PAD who are often undertreated in spite of the proven benefits of guideline-based approach. There is currently no proof that identification of asymptomatic atherosclerosis and PVD improves clinical outcomes in patients who are already in prevention programs. Revascularization should be performed only in symptomatic vascular beds, using the least aggressive method according to consensual decision of a multidisciplinary vascular team.

Limb salvage after aneurysmal degeneration of a cryopreserved vein allograft: Searching the autologous veins of the arm is worth the effort

CLINICAL DATA

We hereby report a case of limb salvage involving a 64-year-old man who was hospitalized with ischemic foot ulcers for two months. Endarterectomy with patching and stenting of the left iliofemoral artery failed. A composite bypass of two segments of the endarterectomized superficial femoral artery and a cryopreserved saphenous vein graft was implanted one week later. On day 4 postoperatively, an infection (Staphylococcus epidermidis and Pseudomonas aeruginosa) was treated empirically with antibiotics. Four months later, the femoro-tibial bypass thrombosed and the patency was restored by thrombolysis. The aneurysmal cryopreserved vein was excised. Iterative complications followed and final success was attained after implantation of autologous cephalic and basilic veins. Four years later, this femoro-tibial is still patent.

PATHOLOGICAL ANALYSES

After a gross observation, the explant was dissected and the most significant sections were processed for histology, followed by analyses in scanning electron microscopy, light microscopy and transmission electron microscopy.

RESULTS

The explanted specimen showed a smooth flow surface proximally but a severe distortion distally, with an accumulation of poorly organized mural thrombi. The wall of the arterialized vein was accompanied with an important inflammatory reaction. The degradation of the collagen structure was evidenced in TEM. The fibrils of collagen were still individualized but were fragmented and did not display parallelly. The regular banding was preserved. The presence of Pseudomonas aeruginosa was shown inside the wall of the homologous vein.

COMMENTS

In case of sepsis, the most aggressive antibiotic treatments cannot fully eliminate the bacteremic colonizations within the wall of an alternative conduit. The cephalic and basilic autologous veins are proved to be preferable in absence of the autologous saphenous vein. The amputation was prevented and four years later the bypass is still patent. This is an outstanding result based upon the comorbidities of the patient. The most aggressive harvesting shall be recommended. This patient represented a considerable challenge and the clinical result is highly gratifying: the search for the autologous cephalic and basilic veins proved to be worth the effort.

Arterioplasty using gastroepiploic artery patch for common femoral artery occlusive disease

We present the first case of arterioplasty of the common femoral artery performed using a gastroepiploic artery (GEA) patch for a 59-year-old man on haemodialysis. He was incidentally diagnosed with coronary artery disease with left main trunk stenosis and double-vessel disease upon screening examination for peripheral artery disease. Preoperative computed tomography revealed a severely narrowed right common femoral artery. We planned a simultaneous off-pump coronary artery bypass grafting (CABG) involving the bilateral internal thoracic arteries and GEA, and endarterectomy of the right common femoral artery. Because the remnant GEA was sufficiently long and its diameter was sufficiently large, we used a GEA patch during arterioplasty to preserve the saphenous vein. This method is limited to simultaneous surgery with CABG using GEA but is a useful alternative for preserving the saphenous vein.

Protamine sulfate use during tibial bypass does not appear to increase thrombotic events or affect short-term graft patency

OBJECTIVES

While the use of protamine sulfate as a heparin reversal agent has been extensively reviewed in patients undergoing carotid endarterectomy and coronary artery bypass grafting, there is a lack of literature on protamine's effects on lower extremity bypasses. The purpose of this study was to determine the risk of protamine sulfate dosing after tibial bypass on thrombotic or bleeding events, including early bypass failure.

METHODS

We performed a retrospective review of our institutional database for patients undergoing primary distal peripheral bypass from January 2009 through December 2015 (contralateral bypass was considered to be a new primary bypass). Primary endpoints include composite thrombotic events (myocardial infarction, stroke, amputation at 30 days and patency less than 30 days) and composite bleeding events (bleeding or transfusion).

RESULTS

A total of 152 tibial or peroneal bypasses in 136 patients with critical limb ischemia were identified. Of these, 78 (57.4%) patients received protamine sulfate intraoperatively and 58 (42.6%) did not. There were no differences in composite thrombotic or hemorrhagic outcomes. Protamine use had no effect on the rates of perioperative MI (9.0% versus 3.5%, p = 0.20), stroke (1.3% versus 1.7%, p = 0.83), or perioperative mortality (5.1% versus 3.5%, p = 0.64). There was no significant difference in composite post-operative bleeding events (20.7% versus 14.1%, p = 0.31) or composite thrombotic events (17.2% versus 18.0%, p = 0.91). Patients who received protamine undergoing bypass with non-autogenous conduit had significantly higher-recorded median operative blood loss (250 mL versus 150 mL, p = 0.0097) and median procedure lengths (265 min versus 201 min, p = 0.0229). No difference in 30-day amputation-free survival was noted (91.0% versus 91.4%, p = 0.94). Follow-up Kaplan-Meier estimation did not demonstrate a difference in 30-day patency (91.7% versus 88.5%, p = 0.52).

CONCLUSIONS

Heparin reversal with protamine sulfate after tibial or peroneal bypass grafting is not associated with higher cardiovascular morbidity, bypass thrombosis, amputation, or mortality. Additionally, there was no statistically significant difference in post-operative bleeding or thrombosis complications for patients who did not receive protamine, although the findings are suggestive of a potential difference in a more adequately powered study. Our results suggest that protamine sulfate is safe for intraoperative use without increased risk of thrombotic complications or early tibial bypass graft failure.

Prognostic implications of peripheral artery disease in coronary artery disease

Prevalence of peripheral arterial disease in patients with coronary artery disease is considerably higher than in the general population. A graded increase in the risk of major cardiovascular events in a variety of clinical settings is associated with the number of arterial beds affected by peripheral arterial disease. This is not surprising, considering that both coronary artery disease and peripheral arterial disease are linked to a higher prevalence of cardiovascular risk factors and a greater incidence of atherosclerotic burden. Aggressive lipid lowering therapy is associated with less coronary and peripheral arterial disease progression and greater regression. On the contrary, blood pressure therapy should be carefully managed, considering the association of both high and low values of pressure with adverse outcomes.

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.

Acellular vascular matrix grafts from human placenta chorion: Impact of ECM preservation on graft characteristics, protein composition and in vivo performance

Small diameter vascular grafts from human placenta, decellularized with either Triton X-100 (Triton) or SDS and crosslinked with heparin were constructed and characterized. Graft biochemical properties, residual DNA, and protein composition were evaluated to compare the effect of the two detergents on graft matrix composition and structural alterations. Biocompatibility was tested in vitro by culturing the grafts with primary human macrophages and in vivo by subcutaneous implantation of graft conduits (n = 7 per group) into the flanks of nude rats. Subsequently, graft performance was evaluated using an aortic implantation model in Sprague Dawley rats (one month, n = 14). In situ graft imaging was performed using MRI angiography. Retrieved specimens were analyzed by electromyography, scanning electron microscopy, histology and immunohistochemistry to evaluate cell migration and the degree of functional tissue remodeling. Both decellularization methods resulted in grafts of excellent biocompatibility in vitro and in vivo, with low immunogenic potential. Proteomic data revealed removal of cytoplasmic proteins with relative enrichment of ECM proteins in decelluarized specimens of both groups. Noteworthy, LC-Mass Spectrometry analysis revealed that 16 proteins were exclusively preserved in Triton decellularized specimens in comparison to SDS-treated specimens. Aortic grafts showed high patency rates, no signs of thrombus formation, aneurysms or rupture. Conduits of both groups revealed tissue-specific cell migration indicative of functional remodeling. This study strongly suggests that decellularized allogenic grafts from the human placenta have the potential to be used as vascular replacement materials. Both detergents produced grafts with low residual immunogenicity and appropriate mechanical properties. Observed differences in graft characteristics due to preservation method had no impact on successful in vivo performance in the rodent model.

The Usefulness of Biosynthetic Vascular Graft Omniflow II and Autologous Veins for the Treatment of Massive Infection of Dacron Vascular Graft with Enterococcus faecalis HLAR

Infections of vascular grafts are the most severe complications in vascular surgery. We present the case of a 73-year-old male with infection of a dacron prosthesis with a strain of Enterococcus faecalis. The patient was treated with replacement of a full prosthesis with a combined graft constructed from Biosynthetic Vascular graft Omniflow and autologous veins. This graft is recommended for implantation in patients with a higher risk of infection. Our case is one of the first reported usage of this kind of graft in the aortic region and in a 2 years observation period no recurrence of infection was observed.