Drug-coated balloons versus conventional percutaneous transluminal angioplasty for treatment-naïve dysfunctional arteriovenous fistulas.: A 10-year single center retrospective study.

OBJECTIVES: To compare the primary patency and restenosis rates in treatment naieve dialysis arteriovenous fistulas (AVFs) after drug-coated balloons (DCB) versus plain balloon angioplasty (PTA). METHODS: This retrospective study included 157 patients who underwent AVF angioplasty for treatment-native AVF stenosis between January 2012 to 2022. The fistulas were Brachiocephalic (75%), Brachiobasilic (17%), and radiocephalic (8%). The index intervention was with either DCB or percutaneous transluminal angioplasty (PTA) with subsequent follow up. Patients with central venous stenosis, thrombosed fistula, fistula stents, AV graft or surgical intervention after the index procedure were excluded. RESULTS: Arteriovenous fistula angioplasty was done in 28 patients using DCB and in 129 patients using PTA. A total of 108 patients presented with a single stenosis, 42 with 2 stenoses, and 7 with 3 stenoses. The location of these stenoses was in the venous outflow (57%), the juxta anastomotic segment (31%), and cephalic arch (12%). The median time to re-intervention for the PTA was 216 days compared to 304 days for the DCB (p=0.079). Primary patency at 6 months was 60.4% for PTA and 75% for DCB (p=0.141) CONCLUSION: Although DCB angioplasty of treatmentnaïve dysfunctional AVF tends to improve the time to intervention and 6-month primary patency compared to PTA, this difference did not reach statistical significance.

Nurse-assisted arterio-venous fistula cannulation during home hemodialysis: first results of the DIADIDEAL study / La ponction de fistule assistée par infirmier libéral en hémodialyse à domicile : premiers résultats de l'étude DIADIDEAL.

Introduction: We have launched a pilot study, called DIADIDEAL, to propose nurse-assistance at home for arterio-venous fistula (AVF) cannulation in home hemodialysis (HHD) patients. The aim of the present study was to describe enrollment of the patients and their nurses. Materials: All prevalent HD patients on 30th November 2018 with no medical contraindication to HDD treatment and all incident patients on dialysis from the 30th November 2018 to the 21st April 2023 were eligible. Results: Among 155 prevalent HD patients, 4 patients were included. Among the 276 incident patients on dialysis during the study period, 6 were included. We have phoned 23 nurse centers during the recruitment period. Eight of them agreed to learn in our unit how to cannulate AVF; 27 private nurses were enrolled. Discussion: The results of the DIADIDEAL study will be available in 2024; we hope it will lead to a reimbursement of nurse-AVF cannulation at home in HDD.

Introduction: L'étude DIADIDEAL est une étude pilote sur la ponction de fistule artério-veineuse (FAV) assistée par infirmier libéral en hémodialyse à domicile (HDD). L'objectif de l'étude actuelle est de rapporter le recrutement des patients et de leurs infirmiers diplômés d'État libéraux (IDEL). Matériels et méthodes: Tous les patients prévalents en HD au 30 novembre 2018 n'ayant pas de contre-indication médicale à un traitement par HDD ainsi que tous les patients incidents en dialyse du 30 novembre 2018 au 21 avril 2023 étaient éligibles. Résultats: Parmi les 155 patients prévalents en hémodialyse, 4 ont été inclus. Parmi les 276 patients incidents en dialyse sur la période, 6 ont été inclus dans l'étude. Parmi les 23 cabinets IDEL contactés pour l'étude, 8 ont accepté et 27 IDEL ont été formés à la ponction de FAV. Discussion: Les résultats de l'étude DIADIDEAL seront disponibles en 2024 et viseront à obtenir une nomenclature pour l'acte de ponction de FAV par les IDEL.

Identifying problematic arteriovenous fistula with CFD-derived resistance: An exploratory study.

Arteriovenous fistula (AVF) is the optimal form of vascular access for most haemodialysis dependant patients; however, it is prone to the formation of stenoses that compromise utility and longevity. Whilst there are many factors influencing the development of these stenoses, pathological flow-related phenomena may also incite the formation of intimal hyperplasia, and hence a stenosis. Repeated CFD-derived resistance was calculated for six patient who had a radiocephalic AVF, treated with an interwoven nitinol stent around the juxta-anastomotic region to address access dysfunction. A three-dimensional freehand ultrasound system was used to obtain patient-specific flow profiles and geometries, before performing CFD simulations to replicate the flow phenomena in the AVF, which enabled the calculation of CFD-derived resistance. We presented six patient cases who were examined before and after treatment and our results showed a 77% decrease in resistance, recorded after a surgical intervention to address access dysfunction. Problematic AVFs were found to have high resistance, particularly in the venous segment. AVFs with no reported clinical problems, and clinical patency, had low resistance in the venous segment. There did not appear to be any relationship with clinical problems/patency and resistance values in the arterial segment. Identifying changes in resistance along the circuit allowed stenoses to be identified, independent to that determined using standard sonographic criteria. Our exploratory study reveals thatCFD-derived resistance is a promising metric that allows for non-invasive identification of diseased AVFs. The pipeline analysis enabled regular surveillance of AVF to be studied to aid with surgical planning and outcome, further exhibiting its clinical utility.

The predictive value of systemic immune-inflammation index for vascular access survival in chronic hemodialysis patients.

Objective: To examine the prognostic values of systemic immune-inflammation indices of hemodialysis (HD) vascular access failure and develop a prediction model for vascular access failure based on the most pertinent systemic immune-inflammation index. Study design: A prospective cohort study. Setting & participants: Patients undergoing autogenous HD vascular access surgeries or arteriovenous graft as a permanent hemodialysis access in a tertiary center in southwest China from January 2020 to June 2022. Predictors: Systemic immune-inflammation indices, including NLR, dNLR, AAPR, SIRI, SII, PNI, PLR, and LIPI, and clinical variables. Outcomes: The outcome was defined as survival of the hemodialysis access, with both occluded and stenotic access being considered as instances of access failure. Analytical approach: Cox proportional hazard regression model. Results: 2690 patients were included in the study population, of whom 658 experienced access failure during the follow-up period. The median duration of survival for HD vascular access was 18 months. The increased systemic immune-inflammation indices, including dNLR, NLR, SII, PNI, SIRI, PLR, and LIPI, are predictive of HD access failure, with SII demonstrating the strongest prognostic value. A simple SII-based prediction model for HD access failure was developed, achieving C-indexes of 0.6314 (95% CI: 0.6249 - 0.6589) and 0.6441 (95% CI: 0.6212 - 0.6670) for predicting 6- and 12-month access survival, respectively. Conclusions: Systemic immune-inflammation indices are significantly and negatively associated with HD vascular access survival. A simple SII-based prediction model was developed and anticipates further improvement through larger study cohort and validation from diverse centers.

Triglyceride glucose index as a marker of primary patency rate of arteriovenous fistula in diabetic hemodialysis patients.

OBJECTIVE: Arteriovenous fistula (AVF) structures are vital formations used for hemodialysis. Diabetes mellitus (DM) is a critical disease affecting the vascular system. The triglyceride glucose (TyG) index has been shown to be associated with major adverse cardiovascular events in patients with Type 2 DM. In this study, we aimed to investigate the effect of the TyG index on the primary AVF patency of diabetic patients. PATIENTS AND METHODS: Between March 2018 and March 2023, patients with DM who underwent AVF surgery in our clinic due to end-stage renal disease were retrospectively included in this study. The patients who could receive hemodialysis were determined as Group 1, and those who could not were determined as Group 2. RESULTS: A total of 189 patients were included in the study. Those who did not develop AVF primary failure were included in Group 1 [n=138, median age = 59 (22-77) years], and those who did were included in Group 2 [n=51, median age = 63 (20-81) years]. In the multivariate analysis, age >70 years (OR: 0.871, 95% CI: 0.594-0.983, p=0.039), the presence of PAD (OR: 0.582, 95% CI: 0.0.458-0.896, p=0.046), and TyG index (OR: 0.879, 95% CI: 0.591-0.916, p<0.001) were determined as independent predictors for primary AVF failure. CONCLUSIONS: This study demonstrated that the TyG index value, calculated from blood samples taken at the time of hospital admission in hemodialysis patients with diabetes mellitus (DM), is an independent predictor of primary AVF failure following AVF surgery.

Clinical outcomes and predictive factors of stent grafts treatment for symptomatic central venous obstruction in end stage kidney disease patients with arteriovenous access.

To assess the efficacy of stent grafts (SGs) in managing central venous obstruction disease (CVOD) in hemodialysis (HD) patients with arteriovenous (AV) access, and to identify predictive factors influencing the SG treatment outcomes. HD subjects with CVOD who underwent SGs placement at our center between August 2018 and June 2022 were enrolled. Survival curve analysis using the Kaplan-Meier method and log-rank test was performed. Cox proportional hazards regression analysis was employed to identify predictive factors associated with outcomes. A total of 59 SG implantation procedures for CVOD were analyzed, comprising 30 cases of stenosis and 29 cases of occlusion. The access circuit primary patency (ACPP) at 6, 12, and 24 months post-SG placement were 80.9%, 53.8%, and 31.4%, respectively, while, the target lesion primary patency (TLPP) were 91.3%, 67.6%, and 44.5%, respectively. Subgroup analysis revealed higher TLPP in the stenosis group compared to the occlusion group, although the difference was not statistically significant (P = 0.165). The TLPP was significantly improved by SG placement in those who had antecedent balloon dilations (P < 0.001). Cox proportional hazards regression identified target lesion length ≥ 30 mm and procedure defects as independent predictors of lower TLPP after SG treatment for CVOD in HD patients. SG placement demonstrates safety and efficacy in managing CVOD among HD patients, leading to improved TLPP of endovascular therapy (EVT) for CVOD. Notably, long target lesions (≥ 30 mm) and procedure defects emerged as predictive factors influencing TLPP.

Heterogeneous gene expression during early arteriovenous fistula remodeling suggests that downregulation of metabolism predicts adaptive venous remodeling.

Clinical outcomes of arteriovenous fistulae (AVF) for hemodialysis remain inadequate since biological mechanisms of AVF maturation and failure are still poorly understood. Aortocaval fistula creation (AVF group) or a sham operation (sham group) was performed in C57BL/6 mice. Venous limbs were collected on postoperative day 7 and total RNA was extracted for high throughput RNA sequencing and bioinformatic analysis. Genes in metabolic pathways were significantly downregulated in the AVF, whereas significant sex differences were not detected. Since gene expression patterns among the AVF group were heterogenous, the AVF group was divided into a 'normal' AVF (nAVF) group and an 'outliers' (OUT) group. The gene expression patterns of the nAVF and OUT groups were consistent with previously published data showing venous adaptive remodeling, whereas enrichment analyses showed significant upregulation of metabolism, inflammation and coagulation in the OUT group compared to the nAVF group, suggesting the heterogeneity during venous remodeling reflects early gene expression changes that may correlate with AVF maturation or failure. Early detection of these processes may be a translational strategy to predict fistula failure and reduce patient morbidity.

Educational video for self-care with arteriovenous fistula in renal patients: randomized clinical trial.

OBJECTIVE: to evaluate the effect of an educational video on the knowledge, attitude, and practice of self-care with arteriovenous fistula in patients undergoing hemodialysis treatment. METHOD: randomized controlled clinical trial, with two arms and single-blind. The intervention used an educational video on arteriovenous fistula self-care. The Fistula Self-Care Knowledge, Attitude, and Practice Scale was applied to 27 renal patients on hemodialysis in the control group and 28 in the intervention group at baseline, after seven and fourteen days. The data was analyzed using the Statistical Package for the Social Sciences software, using the chi-square test, Student's t-test, Mann-Whitney test, and Friedman's test with post-hoc analysis for multiple comparisons. RESULTS: there were statistically significant differences in the knowledge and practice of self-care with the fistula at 0, 7 and, 14 days in the intervention (p= 0.004 and p<0.001, respectively) and control groups (p<0.001 for knowledge and practice). Attitude showed a significant difference at follow-up (p<0.001), but the post-hoc analysis did not confirm the significance obtained. CONCLUSION: patients' knowledge and practice showed significant increases at follow-up in the control and intervention groups, while the increase in attitude was not significant in either group. Clinical trial, registration number: U1111-1241-6730.

Factor XI inhibition in hemodialysis patients: the safer anticoagulation?

Chronic hemodialysis patients exhibit an excessive cardiovascular risk and a marked increase in both thromboembolism and bleeding episodes. Factor XI inhibition may provide anticoagulation, with a low risk of bleeding, and several factor XI inhibitors, including fesomersen, an antisense oligonucleotide, are under development. Recently, a phase 2 study of fesomersen showed a good safety profile in chronic hemodialysis patients and suggested that clotting rates of the arteriovenous fistula and the dialysis circuit are lower.

Long-term survival of patients receiving home hemodialysis with self-punctured arteriovenous access.

OBJECTIVE: To determine the long-term survival of patients receiving home hemodialysis (HHD) through self-punctured arteriovenous access. METHODS: We conducted an observational study of all patients receiving HHD at our facility between 2001 and 2020. The primary outcome was treatment survival, and it was defined as the duration from HHD initiation to the first event of death or technique failure. The secondary outcomes were the cumulative incidence of technique failure and mortality. Cox proportional hazard models were used to identify the predictive factors for treatment survival. RESULTS: A total of 77 patients (mean age, 50.7 years; 84.4% male; 23.4% with diabetes) were included. The median dialysis duration was 18 hours per week, and all patients self-punctured their arteriovenous fistula. During a median follow-up of 116 months, 30 treatment failures (11 deaths and 19 technique failures) were observed. The treatment survival was 100% at 1 year, 83.5% at 5 years, 67.2% at 10 years, and 34.6% at 15 years. Age (adjusted hazard ratio [aHR], 1.07) and diabetes (aHR, 2.45) were significantly associated with treatment survival. Cardiovascular disease was the leading cause of death, and vascular access-related issues were the primary causes of technique failure, which occurred predominantly after 100 months from HHD initiation. CONCLUSION: This study showed a favorable long-term prognosis of patients receiving HHD. HHD can be a sustainable form of long-term kidney replacement therapy. However, access-related technique failures occur more frequently in patients receiving it over the long term. Therefore, careful management of vascular access is crucial to enhance technique survival.

Doppler ultrasound surveillance of recently formed haemodialysis arteriovenous fistula: the SONAR observational cohort study.

Background: Arteriovenous fistulas are considered the best option for haemodialysis provision, but as many as 30% fail to mature or suffer early failure. Objective: To assess the feasibility of performing a randomised controlled trial that examines whether, by informing early and effective salvage intervention of fistulas that would otherwise fail, Doppler ultrasound surveillance of developing arteriovenous fistulas improves longer-term arteriovenous fistula patency. Design: A prospective multicentre observational cohort study (the 'SONAR' study). Setting: Seventeen haemodialysis centres in the UK. Participants: Consenting adults with end-stage renal disease who were scheduled to have an arteriovenous fistula created. Intervention: Participants underwent Doppler ultrasound surveillance of their arteriovenous fistulas at 2, 4, 6 and 10 weeks after creation, with clinical teams blinded to the ultrasound surveillance findings. Main outcome measures: Fistula maturation at week 10 defined according to ultrasound surveillance parameters of representative venous diameter and blood flow (wrist arteriovenous fistulas: ≥ 4 mm and > 400 ml/minute; elbow arteriovenous fistulas: ≥ 5 mm and > 500 ml/minute). Mixed multivariable logistic regression modelling of the early ultrasound scan data was used to predict arteriovenous fistula non-maturation by 10 weeks and fistula failure at 6 months. Results: A total of 333 arteriovenous fistulas were created during the study window (47.7% wrist, 52.3% elbow). By 2 weeks, 37 (11.1%) arteriovenous fistulas had failed (thrombosed), but by 10 weeks, 219 of 333 (65.8%) of created arteriovenous fistulas had reached maturity (60.4% wrist, 67.2% elbow). Persistently lower flow rates and venous diameters were observed in those fistulas that did not mature. Models for arteriovenous fistulas' non-maturation could be optimally constructed using the week 4 scan data, with fistula venous diameter and flow rate the most significant variables in explaining wrist fistula maturity failure (positive predictive value 60.6%, 95% confidence interval 43.9% to 77.3%), whereas resistance index and flow rate were most significant for elbow arteriovenous fistulas (positive predictive value 66.7%, 95% confidence interval 48.9% to 84.4%). In contrast to non-maturation, both models predicted fistula maturation much more reliably [negative predictive values of 95.4% (95% confidence interval 91.0% to 99.8%) and 95.6% (95% confidence interval 91.8% to 99.4%) for wrist and elbow, respectively]. Additional follow-up and modelling on a subset (n = 192) of the original SONAR cohort (the SONAR-12M study) revealed the rates of primary, assisted primary and secondary patency arteriovenous fistulas at 6 months were 76.5, 80.7 and 83.3, respectively. Fistula vein size, flow rate and resistance index could identify primary patency failure at 6 months, with similar predictive power as for 10-week arteriovenous fistula maturity failure, but with wide confidence intervals for wrist (positive predictive value 72.7%, 95% confidence interval 46.4% to 99.0%) and elbow (positive predictive value 57.1%, 95% confidence interval 20.5% to 93.8%). These models, moreover, performed poorly at identifying assisted primary and secondary patency failure, likely because a subset of those arteriovenous fistulas identified on ultrasound surveillance as at risk underwent subsequent successful salvage intervention without recourse to early ultrasound data. Conclusions: Although early ultrasound can predict fistula maturation and longer-term patency very effectively, it was only moderately good at identifying those fistulas likely to remain immature or to fail within 6 months. Allied to the better- than-expected fistula patency rates achieved (that are further improved by successful salvage), we estimate that a randomised controlled trial comparing early ultrasound-guided intervention against standard care would require at least 1300 fistulas and would achieve only minimal patient benefit. Trial Registration: This trial is registered as ISRCTN36033877 and ISRCTN17399438. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: NIHR135572) and is published in full in Health Technology Assessment; Vol. 28, No. 24. See the NIHR Funding and Awards website for further award information.

For people with advanced kidney disease, haemodialysis is best provided by an 'arteriovenous fistula', which is created surgically by joining a vein onto an artery at the wrist or elbow. However, these take about 2 months to develop fully ('mature'), and as many as 3 out of 10 fail to do so. We asked whether we could use early ultrasound scanning of the fistula to identify those that are unlikely to mature. This would allow us to decide whether it would be practical to run a large, randomised trial to find out if using early ultrasound allows us to 'rescue' fistulas that would otherwise fail. We invited adults to undergo serial ultrasound scanning of their fistula in the first few weeks after it was created. We then analysed whether we could use the data from the early scans to identify those fistulas that were not going to mature by week 10. Of the 333 fistulas that were created, about two-thirds reached maturity by week 10. We found that an ultrasound scan 4 weeks after fistula creation could reliably identify those fistulas that were going to mature. However, of those fistulas predicted to fail, about one-third did eventually mature without further intervention, and even without knowing what the early scans showed, another third were successfully rescued by surgery or X-ray-guided treatment at a later stage. Performing an early ultrasound scan on a fistula can provide reassurance that it will mature and deliver trouble-free dialysis. However, because scans are poor at identifying fistulas that are unlikely to mature, we would not recommend their use to justify early surgery or X-ray-guided treatment in the expectation that this will improve outcomes.

Regulation of vascular remodeling by immune microenvironment after the establishment of autologous arteriovenous fistula in ESRD patients.

Autogenous arteriovenous fistula (AVF) is the preferred dialysis access for receiving hemodialysis treatment in end-stage renal disease patients. After AVF is established, vascular remodeling occurs in order to adapt to hemodynamic changes. Uremia toxins, surgical injury, blood flow changes and other factors can induce inflammatory response, immune microenvironment changes, and play an important role in the maintenance of AVF vascular remodeling. This process involves the infiltration of pro-inflammatory and anti-inflammatory immune cells and the secretion of cytokines. Pro-inflammatory and anti-inflammatory immune cells include neutrophil (NEUT), dendritic cell (DC), T lymphocyte, macrophage (Mφ), etc. This article reviews the latest research progress and focuses on the role of immune microenvironment changes in vascular remodeling of AVF, in order to provide a new theoretical basis for the prevention and treatment of AVF failure.

Internal fistula stenosis with true pseudoaneurysm formation in a patient on maintenance hemodialysis: A case report.

BACKGROUND: Arteriovenous fistula stenosis can directly lead to the formation of autologous arteriovenous fistula aneurysms (AVFAs), but the coexistence of true and pseudoaneurysms is relatively rare. The coexistence of true and pseudoaneurysms increases the risk of rupture of the arteriovenous fistula and complicates subsequent surgical intervention, potentially posing a threat to the patient's life, and thus requires significant attention. CASE PRESENTATION: The patient presented with arteriovenous fistula (AVF) after hemodialysis 6 years ago. 2 years ago, the patient presented with a mass that had formed near the left forearm arteriovenous fistula and gradually increased in size. Preoperatively, the AVF stenosis was identified as the cause of the mass formation, and the patient was operated on. First, the blood flow was controlled to reduce the pressure at the aneurysm, and then the incision was enlarged to separate the AVF anastomosis from the mass area. The stenotic segment of the true and pseudo aneurysms and cephalic vein was removed and the over-dilated proximal cephalic vein was locally narrowed and subsequently anastomosed with the proximal radial artery to create AVF. The patient was dialyzed with an internal fistula the next day and showed no clinical manifestations related to end-limb ischemia. CONCLUSION: We removed a true pseudoaneurysm in AVF and secured the patient's vascular access. This report provides an effective strategy to manage this condition.

Management of thoracic outlet syndrome in patients with hemodialysis access.

Patients with threatened arteriovenous access are often found to have central venous stenoses at the ipsilateral costoclavicular junction, which may be resistant to endovascular intervention. Stenoses in this location may not resolve unless surgical decompression of thoracic outlet is performed to relieve the extrinsic compression on the subclavian vein. The authors reviewed the management of dialysis patients with central venous lesions at the thoracic outlet, as well as the role of surgical decompression with first-rib resection or claviculectomy for salvage of threatened, ipsilateral dialysis access.

Sharp needle reconstructs peripheral outflow for patients with malfunctional arteriovenous fistula.

OBJECTIVE: To investigate the feasibility and efficacy of combining ultrasound-guided sharp needle technique with percutaneous transluminal angioplasty (PTA) for treating outflow stenosis or dysfunction in arteriovenous fistula (AVF) among hemodialysis patients. METHODS: From October 2021 to March 2023, patients with occluded or malfunctional fistula veins not amenable to regularly angioplasty were retrospectively enrolled in the study. They underwent ultrasound-guided sharp needle intervention followed by PTA. Data on the location and length between the two veins, technical success, clinical outcomes, and complications were collected. Patency rates post-angioplasty were calculated through Kaplan-Meier analysis. RESULTS: A total of 23 patients were included. The mean length of the reconstructed extraluminal segment was 3.18 cm. The sharp needle opening was performed on the basilic vein (60.9%), brachial vein (26.1%), or upper arm cephalic vein (13%) to create outflow channels. Postoperatively, all cases presented with mild subcutaneous hematomas around the tunneling site and minor diffuse bleeding. The immediate patency rate for the internal fistulas was 100%, with 3-month, 6-month, and 12-month patency rates at 91.3%, 78.3%, and 43.5%, respectively. CONCLUSION: Sharp needle technology merged with PTA presents an effective and secure minimally invasive method for reconstructing the outflow tract, offering a new solution for recanalizing high-pressure or occluded fistulas.

Factors contributing to patency after aneurysmorrhaphy and outflow repair in arteriovenous fistula aneurysm treatment.

INTRODUCTION: Vascular access-related aneurysms (VARA) are a complication of arteriovenous fistulas. Repair techniques have been described in the literature with varied outcomes. MATERIALS AND METHODS: We conducted a prospective cohort study on patients who had VARA repair over 41 months. The indication for repair was an aneurysmal arteriovenous fistula (AVF) at risk of haemorrhage or difficulty in cannulation. Pseudoaneurysms, infected AVF and bleeding VARA were excluded. All patients underwent outflow stenosis treatment when present, followed by aneurysmorrhaphy. They were monitored periodically over 12 months, measuring functional primary and cumulative patency and access flow. We studied the patient demography, access flow and presence of outflow stenosis. Access flow was measured from the brachial artery (Qa) as a surrogate using ultrasonography. A Kaplan-Meier survival analysis was used to predict the primary and cumulative patency at 12 months and factors contributing to 12-month patency were analysed. RESULTS: A total of 64 patients were recruited for this study, of whom 58 completed the study. Most of the participants were male (67%) with a median age of 45 years. Forty-six patients (79.3%) had brachiocephalic fistula (BCF) aneurysms. Thirty-nine (67.2%) had preexisting outflow stenoses that required intervention. All patients underwent an aneurysmorrhaphy, of whom 12% had a cephalic arch vein transposition due to severe stenosis. Primary patency at 12 months was 86%, whereas the cumulative patency rate was 95%. Patency was significantly associated with younger age and showed a positive trend with higher preintervention Qa. Symptomatic recurrent stenosis developed in 17.2% of the cohort. CONCLUSION: Improving the patency of VARA entails the treatment of outflow stenosis and aneurysmorrhaphy. Surveillance is important to detect and treat recurrent outflow stenoses. The outcome is better among younger patients with pre-interventional access flow as measured in the brachial artery as a surrogate.

Global variations in funding and use of hemodialysis accesses: an international report using the ISN Global Kidney Health Atlas.

BACKGROUND: There is a lack of contemporary data describing global variations in vascular access for hemodialysis (HD). We used the third iteration of the International Society of Nephrology Global Kidney Health Atlas (ISN-GKHA) to highlight differences in funding and availability of hemodialysis accesses used for initiating HD across world regions. METHODS: Survey questions were directed at understanding the funding modules for obtaining vascular access and types of accesses used to initiate dialysis. An electronic survey was sent to national and regional key stakeholders affiliated with the ISN between June and September 2022. Countries that participated in the survey were categorized based on World Bank Income Classification (low-, lower-middle, upper-middle, and high-income) and by their regional affiliation with the ISN. RESULTS: Data on types of vascular access were available from 160 countries. Respondents from 35 countries (22% of surveyed countries) reported that > 50% of patients started HD with an arteriovenous fistula or graft (AVF or AVG). These rates were higher in Western Europe (n = 14; 64%), North & East Asia (n = 4; 67%), and among high-income countries (n = 24; 38%). The rates of > 50% of patients starting HD with a tunneled dialysis catheter were highest in North America & Caribbean region (n = 7; 58%) and lowest in South Asia and Newly Independent States and Russia (n = 0 in both regions). Respondents from 50% (n = 9) of low-income countries reported that > 75% of patients started HD using a temporary catheter, with the highest rates in Africa (n = 30; 75%) and Latin America (n = 14; 67%). Funding for the creation of vascular access was often through public funding and free at the point of delivery in high-income countries (n = 42; 67% for AVF/AVG, n = 44; 70% for central venous catheters). In low-income countries, private and out of pocket funding was reported as being more common (n = 8; 40% for AVF/AVG, n = 5; 25% for central venous catheters). CONCLUSIONS: High income countries exhibit variation in the use of AVF/AVG and tunneled catheters. In low-income countries, there is a higher use of temporary dialysis catheters and private funding models for access creation.

Patients, healthcare providers, and general population preferences for hemodialysis vascular access: a discrete choice experiment.

Background: A patient-centered dialysis treatment option requires an understanding of patient preferences for alternative vascular accesses and nephrologists often face difficulties when recommending vascular access to end-stage kidney disease (ESKD) patients. We aimed to quantify the relative importance of various vascular access characteristics to patients, healthcare providers and general population, and how they affect acceptability for patients and healthcare providers. Methods: In a discrete choice experiment, patients with maintenance hemodialysis (MHD), healthcare providers, and individuals from the general population were invited to respond to a series of hypothetical vascular access scenarios that differed in five attributes: cumulative patency, infection rate, thrombosis rate, cost, and time to maturation. We estimated the respondents' preference heterogeneity and relative importance of the attributes with a mixed logit model (MXL) and predicted the willingness to pay (WTP) of respondents via a multinomial logit model (MNL). Results: Healthcare providers (n = 316) and the general population (n = 268) exhibited a favorable inclination toward longer cumulative patency, lower access infection rate and lower access thrombosis rate. In contrast, the patients (n = 253) showed a preference for a 3-year cumulative patency, 8% access infection rate, 35% access thrombosis rate and 1.5 access maturity time, with only the 3-year cumulative patency reaching statistical significance. Among the three respondent groups, the general population found cumulative patency less important than healthcare providers and patients did. Patients demonstrated the highest WTP for cumulative patency, indicating a willingness to pay an extra RMB$24,720(US$3,708) for each additional year of patency time. Conclusion: Patients and healthcare providers had a strong preference for vascular access with superior patency. While the general population preferred vascular access with lower thrombosis rates. These results indicate that most patients prefer autogenous arteriovenous fistula (AVF) as an appropriate choice for vascular access due to its superior patency and lower complications than other vascular access types.

Glutathione S-Transferase α4 Alleviates Hyperlipidemia-Induced Vascular Neointimal Hyperplasia in Arteriovenous Grafts via Inhibiting Endoplasmic Reticulum Stress.

ABSTRACT: Neointimal hyperplasia causes the failure of coronary artery bypass grafting. Our previous studies have found that endothelial dysfunction is 1 candidate for triggering neointimal hyperplasia, but which factors are involved in this process is unclear. Glutathione S-transferase α4 (GSTA4) plays an important role in metabolizing 4-hydroxynonenal (4-HNE), a highly reactive lipid peroxidation product, which causes endothelial dysfunction or death. Here, we investigated the role of GSTA4 in neointima formation after arteriovenous grafts (AVGs) with or without high-fat diet (HFD). Compared with normal diet, HFD caused endothelial dysfunction and increased neointima formation, concomitantly accompanied by downregulated expression of GSTA4 at the mRNA and protein levels. In vitro, overexpression of GSTA4 attenuated 4-HNE-induced endothelial dysfunction and knockdown of GSTA4 aggravated endothelial dysfunction. Furthermore, silencing GSTA4 expression facilitated the activation of 4-HNE-induced endoplasmic reticulum stress and inhibition of endoplasmic reticulum stress pathway alleviated 4-HNE-induced endothelial dysfunction. In addition, compared with wild-type mice, mice with knockout of endothelial-specific GSTA4 (GSTA4 endothelial cell KO) exhibited exacerbated vascular endothelial dysfunction and increased neointima formation caused by HFD. Together, these results demonstrate the critical role of GSTA4 in protecting the function of endothelial cells and in alleviating hyperlipidemia-induced vascular neointimal hyperplasia in arteriovenous grafts.