External Scaffold for Venous Graft to Treat Chronic Limb-Threatening Ischemia: Results of the FRAME Vascular Support.

Background: The surgical treatment of chronic limb-threatening ischemia and optimal conduit choice are extensively debated. The presence of suboptimal autologous material, such as varicosities or venous aneurysms, might impair long-term outcomes. Therefore, kink-resistant external supports have been advocated in the recent literature to improve the conduit quality and outcomes. This study analyzes the FRAME external support in venous ectasic grafts in patients with chronic limb-threatening ischemia. Methods: From September 2017 to September 2023, a total of sixteen patients underwent CLTI surgery with FRAME external support for venous grafts. The inclusion criteria for FRAME applications were varicose or ectasic autologous material with a diameter ≥ 4.5 and ≤ 8 mm in an isolated segment or in the entire vein and a higher risk of bypass extrinsic compression (e.g., extra-anatomical venous bypass course). Results: Technical success and intraoperative patency were achieved in all cases. At 30 days, the limb salvage and survival rates were 100%. The primary bypass patency was 93.7% due to an early graft occlusion. No graft infection was registered. In one case, dehiscence of the surgical wound was treated by surgical debridement and antibiotic therapy. Minor amputation was required in four patients. Over a median follow-up of 32 months, two occlusions were observed; one was treated with reoperation and the other with major amputation. The primary patency was 68.7% and the assisted primary patency was 75%. Limb salvage rates observed during the entire follow-up period were 87.5%. No graft infections or dilatation of the reinforced veins were registered. Conclusions: For patients with CLTI undergoing infrainguinal bypass, satisfactory results in terms of patency and limb salvage rates were achieved using the autologous venous material, even if ectasic or varicose, with the vascular external support FRAME.

Long-Term Results of Below-The-Knee Bypass Using a Prosthetic Graft with a Distal Arteriovenous Fistula Interposition.

Surgical bypass is the gold standard treatment in patients affected by chronic limb-threatening ischemia in advanced GLASS stages, according to the Global Vascular Guidelines. For patients in whom an autologous graft is not available, a prosthesis could be used with the adjunct of a distal arteriovenous fistula interposition. The aim of this study was to examine the long-term results of below-the-knee surgical revascularization using a prosthesis with the distal adjunct mentioned above. From 2010 to 2020, we performed 159 lower limb below-the-knee surgical revascularizations using a prosthesis with the creation of an arteriovenous fistula interposition on the distal anastomosis. The GLASS stage was 3 in 100% of patients. The primary patency rates were as follows: 86.7% at 1 year, 57.2% at 3 years, and 12.6% at 5 years. The graft thrombosis rates were 17.4% at 1 year, 42.1% at 3 years, and 64.5% at 5 years. The amputation-free survival rates were 79% at 1 year, 76% at 3 years, and 64% at 5 years. PTFE prosthetic bypass for below-the-knee arteries using an arteriovenous fistula interposition is a good solution in patients without an autologous conduit. This technique offers reasonable graft patency and limb salvage rates.

Ultrasound-guided placement of long peripheral cannula in children with cystic fibrosis.

BACKGROUND: The natural history of cystic fibrosis (CF) lung disease is a chronic deterioration of lung function with intermittent episodes of pulmonary infectious exacerbations (PExs). Reliable venous access is a milestone of effective management of such exacerbations, managed both in hospital and outpatient chronic therapy. The aim of our study was to analyze the feasibility of ultrasound-guided positioning of long peripheral catheters (LPC) as reliable midterm venous access in children affected by CF. METHODS: In this single-center prospective study, over a 60-month period, we included paediatric CF subjects admitted with PExs and undergoing intravenous antibiotic treatment. LPCs were inserted in all participants by paediatric anaesthesiologists with ultrasound guide technique. Prospective data were collected assessing catheter positioning procedure and complications. RESULTS: A total of 122 LPC insertions were performed in 55 CF children. Participants had a median age of 6.75 years (interquatile range: 3.7-13.5) at the time of catheter insertion. Implantation was successful on the first attempt in 86% of cases; 2 (1%) major insertion-related complications were reported. Eighty-eight percent of catheters were electively removed at the end of antibiotic therapy without any complication. Seven percent of the catheters were removed electively for occlusion and 2% for local dislodgment. CONCLUSIONS: The results of the present study suggest that ultrasound-guided positioning of LPCs are safe alternative means of peripheral venous access in children with chronic diseases such as CF.

Initial single-center experience with a new external support device for the creation of the forearm native arteriovenous fistula for hemodialysis.

OBJECTIVE: To assess and compare the maturation rate of the native radiocephalic arteriovenous fistula (RC-AVF) created with and without a nitinol external support (VasQ™ Laminate Medical Technologies Ltd, Tel Aviv, Israel). METHODS: Data of all consecutive patients who underwent the creation of native RC-AVFs at our center between October 2018 and January 2020 was prospectively collected and retrospectively analyzed.Selected patients who had a suitable vein and a radial artery with triphasic flow at preoperative duplex ultrasound exam and were selected for the creation of a radiocephalic fistula were included. Exclusion criteria were: malignant tumors, acute renal failure, previous upper limb revascularization, and septic status. Patency and maturation, vein, and artery diameter and blood flow rate were assessed at the following intervals: post-operatively, 24 h post-operatively, 1 month, 3 months, and 6 months post-operatively. RESULTS: Forty-nine patients (31 males, mean age 65.7 years old) were included. Patients who received VasQ™ devices were 25 (VasQ group), the other 24 formed the control group. All patients underwent radio-cephalic AVF placement (21 on the wrist, 20 on the forearm, 8 on the proximal forearm). There were no perioperative complications and fatalities. At 1, 3, and 6 months, primary patency rates were 96 ± 4%, 96 ± 4%, 91 ± 6% (VasQ group) versus 87 ± 7%, 87 ± 7%, 80 ± 9% (control group, P 0.17), secondary patency rates were 96 ± 4%, 96 ± 4%, 91 ± 6% (VasQ group) versus 95 ± 4%, 90 ± 7%, 90 ± 7% (control group, P 0.79). A significantly larger vein diameter increase postoperatively (P 0.009) and a greater maturation rate (96% vs 74%, p 0.044) were found in the VasQ group compared to the control group. CONCLUSIONS: The use of the VasQ™ device was associated with higher maturation rates and larger vein diameters postoperatively. The patency rates were slightly higher but not significantly. Further studies are needed to confirm these findings.

Cross-sectional analysis of peripheral blood mononuclear cells in lymphopenic and non-lymphopenic relapsing-remitting multiple sclerosis patients treated with dimethyl fumarate.

BACKGROUND: Relapsing-remitting multiple sclerosis (RRMS) is an autoimmune disorder of the central nervous system. Dimethyl Fumarate is a disease-modifying medication used to treat RRMS patients that can induce lymphopenia. We aimed to immunophenotype peripheral blood mononuclear cells (PBMC) in RRMS patients cross-sectionally and examine the characteristics and modifications of lymphopenia over time. METHODS: Characterization of PBMC was done by multiparametric flow cytometry. Patients had been on treatment for up to 4 years and were grouped into lymphopenic (DMF-L) and non-lymphopenic (DMF-N) patients. RESULTS: Lymphopenia affected the cell population changes over time, with other patient characteristics (gender, age, and previous treatment status) also having significant effects. In both lymphopenic and non-lymphopenic patients, PBMC percentages were reduced over time. While overall T and B cells frequencies were not affected, males, older patients and untreated patients had significant changes in B cell subpopulations over time. CD4+ to CD8+T cell ratio increased significantly in lymphopenic patients over time. CD4-CD8-T cell population was similarly reduced in both lymphopenic and non-lymphopenic patients, over time. While the monocyte and NK overall populations were not changed, non-classical monocyte subpopulation decreased over time in lymphopenic patients. We also found CD56-CD16+ and CD56-CD16- NK cells frequencies changed over time in lymphopenic patients. Immune populations showed correlations with clinical outcomes measured by EDSS and relapse rate. Analysis of the overall immunophenotype showed that, while groups divided by other patient characteristics showed differences, the lymphopenia status overrode these differences, resulting in similar immunophenotype within DMF-L. CONCLUSIONS: Our data provide evidence that under the same therapy, lymphopenia affects how the immunophenotype changes over time and can override the differences associated with other patient characteristics and possibly mask other significant changes in the immune profile of patients.

Inframalleolar bypass for chronic limb-threatening ischemia.

The aims of this study were to analyze the results of inframalleolar bypass for chronic limb-threatening ischemia (CLTI) and to identify outcome-predicting factors. All consecutive patients undergoing inframalleolar bypass for CLTI between 2015 and 2018 were included in this retrospective, single-center study. Outflow artery was the most proximal patent vessel segment in continuity with inframalleolar arteries. Bypasses originating from the popliteal artery were defined as 'short bypasses'. Sixty patients underwent inframalleolar bypass, with four patients undergoing bilateral procedures, making a total of 64 limbs included. The mean age was 73 ± 14 and 52 (81%) were male. The great saphenous vein was the preferred conduit (n = 58, 91%), in a devalvulated fashion (n = 56, 88%). Superficial femoral artery was the most common inflow artery for 'long' grafts (n = 22, 34%), while popliteal artery was the inflow artery for all 'short' grafts (n = 25, 39%). Dorsalis pedis artery was chosen as an outflow artery in 41 patients (63%). Median follow-up was 21 months. Two-year primary and secondary patency, limb salvage, amputation-free survival, and overall survival rates were 67 ± 6%, 88 ± 4%, 84 ± 4%, 72 ± 6%, and 85 ± 4%, respectively. At multivariate analysis, dialysis was an independent predictor for poor primary patency (HR, 4.6; 95% CI, 1.62-13.05; p = 0.004), whereas a short bypass was independently associated with an increased primary patency (HR, 0.3; 95% CI, 0.10-0.89; p = 0.03). In conclusion, bypass grafting to the inframalleolar arteries resulted in good patency rates, limb salvage and overall survival. Dialysis patients had lower primary patency but still had good limb salvage and survival. Short bypass was a predictor of improved primary patency.

Evaluation of the Italian transport infrastructures: A technical and economic efficiency analysis.

•The deregulation process played a key role in terms of airport efficiency.•The technical efficiency of 32 Italian airports has been evaluated•The methodological approach has been twofold: DEA and Tobit model•The main results show that efficiency is independent of an airport's size.•The findings highlight the decisive role of public shareholders in small airports.

Simultaneous Superficial Femoral Artery Angioplasty/Stent Plus Popliteal Distal Bypass for Limb Salvage.

BACKGROUND: Treatment of severe critical limb ischemia (CLI) due to superficial femoral artery (SFA) and below-the-knee (BTK) vessels' involvement could be compromised by the lack of a great saphenous vein (GSV) suitable in its entire length. The purpose of this study is to assess the efficacy of a hybrid endovascular and open lower limbs arterial reconstruction in these patients with multilevel, advanced CLI. METHODS: From 2005 to 2019, we performed hybrid endovascular and surgical treatment for limb salvage in SFA-BTK CLI. This consisted of percutaneous transluminal angioplasty (PTA) with or without stenting of the SFA, along with distal origin vein graft bypass. Inclusion criteria were Rutherford category 5 or 6, lack of a suitable GSV, patency of the popliteal artery, steno-obstructive lesions of the SFA, lesions of the 3 crural vessels >5 cm in length each. The follow-up was performed with duplex scan surveillance of both the bypass graft and PTA sites. RESULTS: The hybrid treatment could be performed in 34 patients. Fifty-six percent of the SFA steno-obstructive lesions were treated with simple PTA, except for the application of a bare metal stent in one patient (3%), while in all the SFA occlusions PTA was completed with covered stents (41%). Thirty-four popliteal-to-distal vein bypass grafts bypass grafts have been performed. There were no perioperative PTA or bypass graft failures. Clinical improvement was achieved in 26 (76%) patients. Overall, primary and secondary patency, limb salvage, and survival rates were 65%, 68%, 75%, and 75% at 5 years, respectively. CONCLUSIONS: A hybrid strategy in multilevel SFA-BTK CLI is a well-established approach. Additional studies are warranted to validate these results.

Mathematical determination of the HIV-1 matrix shell structure and its impact on the biology of HIV-1.

Since its discovery in the early 1980s, there has been significant progress in understanding the biology of type 1 human immunodeficiency virus (HIV-1). Structural biologists have made tremendous contributions to this challenge, guiding the development of current therapeutic strategies. Despite our efforts, there are unresolved structural features of the virus and consequently, significant knowledge gaps in our understanding. The superstructure of the HIV-1 matrix (MA) shell has not been elucidated. Evidence by various high-resolution microscopy techniques support a model composed of MA trimers arranged in a hexameric configuration consisting of 6 MA trimers forming a hexagon. In this manuscript we review the mathematical limitations of this model and propose a new model consisting of a 6-lune hosohedra structure, which aligns with available structural evidence. We used geometric and rotational matrix computation methods to construct our model and predict a new mechanism for viral entry that explains the increase in particle size observed during CD4 receptor engagement and the most common HIV-1 ellipsoidal shapes observed in cryo-EM tomograms. A better understanding of the HIV-1 MA shell structure is a key step towards better models for viral assembly, maturation and entry. Our new model will facilitate efforts to improve understanding of the biology of HIV-1.

Isthmic Aortic False Aneurysm Post-Patch Coarctation Aortoplasty: A Hybrid Solution.

We report a case of a 57-year-old female with dextrocardia and a solitary kidney. A patch aortoplasty for isthmic aortic coarctation repair was performed 40 years before when she was admitted to our department for dyspnea. Computed tomography scan showed a giant and saccular 10-cm diameter patch false aneurysm. The ascending aortic diameter was 34 mm and the echocardiography confirmed a severe aortic regurgitation of a bicuspid aortic valve. We decided to perform a 2-step approach: biologic aortic valve and ascending aorta replacement with total debranching of the epiaortic vessels and thoracic endovascular aneurysm repair for complete false aneurysm exclusion.

Editor's Choice - Long-term Survival and Risk Analysis in 136 Consecutive Patients With Type B Aortic Dissection Presenting to a Single Centre Over an 11 Year Period.

OBJECTIVES: To evaluate, in patients with acute type B aortic dissection, the results of medical and endovascular treatment in a large single centre experience and to investigate the clinical and imaging features on presentation that relate to poor outcome. METHODS: This was a retrospective analysis of prospectively collected clinical and CT imaging data. Consecutive patients (136) with acute type B aortic dissection were included in the study over an 11 year period. The characteristics of patients receiving endovascular (complicated) or medical treatment (uncomplicated) were compared. Kaplan-Meier estimators were used to estimate cumulative overall survival and survival free of aortic events. Factors associated with overall and aortic event free survival were also explored using Cox proportional hazards models. RESULTS: The mean follow up was 51 months (1-132), during which time 33 deaths and 48 aortic events occurred. At one and five years, overall survival was 94.0% and 74.8%, respectively, and freedom from aortic events was 75.6% and 58.7%. There was no difference in all cause survival and aortic event free survival at one and five years between the patients treated endovascularly and those receiving medical treatment alone. Risk analysis for aortic events demonstrated the maximum size of the proximal entry tear, the maximum thoracic aortic diameter, and the thoracic aortic false lumen maximum diameter to have a significant effect on the incidence of aortic events. CONCLUSIONS: Active management of patients with type B aortic dissection results in good long-term survival even in the presence of features traditionally associated with adverse outcomes. All patients require close lifetime surveillance as aortic events continue to occur during follow up even after endografting.

Long-term Results of Endovascular Treatment of TASC C and D Aortoiliac Occlusive Disease with Expanded Polytetrafluoroethylene Stent Graft.

BACKGROUND: The aim of this study is to retrospectively analyze the early and long-term outcomes of endovascular treatment of Trans-Atlantic Inter-Society Consensus II class C and D (TASC II) aortoiliac occlusive disease with an expanded polytetrafluoroethylene-covered stent graft. METHODS: Between January 2006 and November 2017, 61 patients (53 males, 8 females), with symptomatic aortoiliac stenotic and/or occlusive disease, were treated with VIABAHN (W.L. Gore and Associates, Flagstaff, Ariz) at 2 University medical centers. The morphology of the lesions was evaluated and classified by contrast-enhanced computed tomography angiography. Demographic data, operation details, and postoperative outcomes were collected. Follow-up data were analyzed by a life-table analysis (Kaplan-Meier test). RESULTS: Mean age of the patients was 64.89 ± 10.77 years (range 44-89). Thirty-seven patients (60.7%) presented with severe claudication (Rutherford 3), whereas 21 (34.4%) were in Rutherford class 4 and the remaining 3 patients (4.9%) suffered from necrotic lesions (Rutherford 5/6). Fifty-six patients were smokers (91.8%), 38 (62.3%) had hypertension, 23 (37.7%) had coronary artery disease, 30 (40.2%) had dyslipidemia, 18 (29.5%) had chronic obstructive pulmonary disease, 6 (9.5%) had renal insufficiency (serum creatinine>2.0 mg/dL) and 24 (39.3%) had diabetes. Technical success was achieved in 59/61 patients (96.7%) with 16 patients (26.2%) requiring combined percutaneous brachial access to obtain iliac recanalization. Perioperative mortality was 1.6%, whereas postoperative major complications occurred in 2 patients (3.6%). The mean number of VIABAHN placed was 1.77/patient. Mean follow-up was 31.5 months (range 1-108) and primary patency at 36 months was 94.9%. Two major amputations of the lower limbs occurred during the follow-up. CONCLUSIONS: Open surgery with the aortobifemoral bypass has been the gold standard treatment for complex aortoiliac occlusive disease although complications and mortality still remain significant issues. Our results suggest that endovascular therapy of TASC C and D iliac lesions using the VIABAHN stent graft is feasible, effective, and has good, long-term patency.

Characterization of lymphopenia in patients with MS treated with dimethyl fumarate and fingolimod.

OBJECTIVE: Lymphopenia is a common occurrence of disease-modifying therapies (DMTs) for relapsing-remitting MS (RRMS). The aim of this study was to dissect the prevalence of various lymphocyte subsets in patients with RRMS treated with 2 DMTs commonly associated with lymphopenia, dimethyl fumarate (DMF), and fingolimod (FTY). METHODS: Multicolor flow cytometry and multiplex assays were used to identify up to 50 lymphocyte subpopulations and to examine the expression of multiple cytokines in selected patients. We compared patients untreated (NT) or treated with FTY or DMF who did (DMF-L) or did not (DMF-N) develop lymphopenia. RESULTS: All FTY patients developed lymphopenia in both T-cell and B-cell compartments. CD41 T cells were more affected by this treatment than CD81 cells. In the B-cell compartment, the CD271IgD2 subpopulation was reduced. T cells but not B cells were significantly reduced in DMF-L. However, within the B cells, CD271 cells were significantly lower. Both CD41 and CD81 subpopulations were reduced in DMF-L. Within the remaining CD41 and CD81 compartments, there was an expansion of the naive subpopulation and a reduction of the effector memory subpopulation. Unactivated lymphocyte from DMF-L patients had significantly higher levels of interferon-γ, interleukin (IL)-12, IL-2, IL-4, IL-6, and IL-1ß compared with DMF-N. In plasma, TNFß was significantly higher in DMF-N and DMF-L compared with NT, whereas CCL17 was significantly higher in DMF-L compared with NT and DMF-N. CONCLUSIONS: This study shows that different treatments can target different lymphocyte compartments and suggests that lymphopenia can induce compensatory mechanisms to maintain immune homeostasis.

Distal Ulnar Artery Aneurysm Repair by End-to-End Technique: A Case Report.

We report the case of a 33-year-old man presented with a posttraumatic 20-mm left ulnar artery aneurysm without intraluminal thrombus in the left hypothenar eminence. The patient reported left hand paresthesia. Because of symptoms and the embolic risk, we decide to plan an aneurysm resection and an interposition graft with inverted basilic vein for adequacy diameter (∼2 mm), but an end-to-end anastomosis was performed instead. We think that the posttraumatic distal artery aneurysm could be treated without a bypass but, after a meticulous anatomic dissection, with a microvascular anastomosis between the artery stumps.

Mycotic Pseudoaneurysm of Internal Carotid Artery Secondary to Lemierre's Syndrome, How to Do It.

We report the case of a patient with internal carotid artery (ICA) mycotic pseudoaneurysm secondary to Lemierre's syndrome, urgently treated. A 75-year-old man presented to E.R. with a left swelling lesion of the neck and complaining left visions lost since that morning, fever, hypotension, and dyspnea. Since 15 days before developing symptoms, he had sore throat and odynophagia treated with a broad coverage of antibiotic therapy for presumed streptococcal pharyngitis. Preoperative computed tomography angiography images revealed a circular lesion, involving the common carotid artery, carotid bulb, and the proximal part of the internal and external carotid arteries. A pseudoaneurysm of the ICA was detected, and the jugular vein was compressed. A Cormier carotid vein graft bypass was performed. Lemierre's syndrome is a rare syndrome, but it is rarer the carotid artery pseudoaneurysm secondary to Lemierre's syndrome. Surgical treatment is safe and durable in patients with severe infection involving the neck.

The role of procalcitonin as a marker of diabetic foot ulcer infection.

Foot ulcers are frequent in diabetic patients and are responsible for 85% of amputations, especially in the presence of infection. The diagnosis of diabetic foot ulcer infection is essentially based on clinical evaluation, but laboratory parameters such as erythrocyte sedimentation rate (ESR), white blood count (WBC), C-reactive protein (CRP) and, more recently, procalcitonin (PCT) could aid the diagnosis, especially when clinical signs are misleading. Fifteen diabetic patients with infected foot ulcers were admitted to our department and were compared with an additional group of patients with non-infected diabetic foot ulcers (NIDFUs). Blood samples were collected from all patients in order to evaluate laboratory markers. In the current study, the diagnostic accuracy of PCT serum levels was evaluated in comparison with other inflammatory markers such as CRP, ESR and WBC as an indicator to make the distinction between infected diabetic foot ulcers (IDFUs) and NIDFUs. CRP, WBC, ESR and especially PCT measurements represent effective biomarkers in the diagnosis of foot infections in diabetic patients particularly when clinical signs are misleading.