Percutaneous creation of an arteriovenous fistula for hemodialysis access

Multi-Center Two-Year Patency Outcomes of Endovascular Arteriovenous Fistulas (endoAVF) Created with a 4 French System

PURPOSE

To assess multicenter two-year patency outcomes of endovascular arteriovenous fistulas (endoAVF) created with the WavelinQ device.

MATERIALS AND METHODS

Patients who had fistulas created at three centers from January 2018 to December 2020 were included in this retrospective study. In total, 112 patients underwent endoAVF creation [40 females, 72 males; mean age 60 years (range 18-88)]. Data collected included patient demographics, location of fistula creation, interventions performed, and brachial artery flows pre- and post-creation. Two-year cumulative patency, functional patency, and primary patency were assessed with Kaplan-Meier methodology. Factors affecting patency and maturation were examined using the Cox proportional hazards model.

RESULTS

Technical success defined as angiographically successful endoAVF creation was 97.3% (109/112). In 11 patients the fistula did not mature for dialysis use. For 98 patients (87%) with endoAVF maturation, 12- and 24-month cumulative patency was 94.3% and 91.7%. Functional patency (two-needle cannulation) at 12 and 24 months was 95.7% and 92.7%, respectively. Median maturation time is 95 days (IQR 51-231 days). Male gender and brachial vein coiling at the time of endoAVF creation were predictive of maturation. There were 34 censored events (four patients undergoing renal transplantation; 30 patients deceased). Number of reinterventions per patient year was 0.73 where 43 were maturation procedures and 101 were maintenance procedures. One Grade 3 complication occurred of arterial access puncture site pseudoaneurysm.

CONCLUSION

A high two-year functional and cumulative patency following endoAVF creation with the WavelinQ device was observed in this multicenter real-world experience Level of Evidence: 3 Level of Evidence III.

Two-Year Cumulative and Functional Patency after Creation of Endovascular Arteriovenous Hemodialysis Fistulae

PURPOSE

To assess 2-year cumulative and functional patency of endovascular arteriovenous fistulae (endoAVF) created with the WavelinQ device.

MATERIALS AND METHODS

Patients who had fistulae created at a single center from December 2019 to December 2020 were included in this retrospective study. Forty-three patients underwent endoAVF creation (22 females, 21 males). Data collected included patient demographics, location of fistula creation, interventions performed, and brachial artery flow before and after creation. Two-year cumulative and functional patency rates were assessed with Kaplan-Meier method, and variables that affected patency and maturation were examined using Cox proportional hazards model.

RESULTS

Technical success was 95% (41/43), and in 4 patients, the fistula did not mature for dialysis use (9.7%). For the remaining 37 patients with endoAVF maturation, 25 had ulnar-ulnar fistulae, 10 had radial-radial fistulae, and 2 had interosseous artery-vein fistulae. Mean maturity time was 73 days, and brachial artery flow of >886 mL/min was predictive of maturation. Mean tunneled dialysis catheter removal time was 133 days. Number of interventions per patient-year was 0.38, where 8 were maturation procedures (5 vein elevations/transpositions and 3 coil embolizations) and 21 were maintenance angioplasties. Two-year cumulative/secondary and functional patency rates were 89.4% and 92.1%, respectively, with a mean follow-up of 665.7 days. Examined variables did not impact cumulative or functional patency. One adverse event was migration of coil to the heart, which was successfully retrieved at time of procedure.

CONCLUSIONS

Two-year patency of 89.4% and functional patency of 92.1% were observed after endoAVF creation with WavelinQ device.

Carbon dioxide automated digital subtraction angiography for endovascular arteriovenous fistulas creation

Recent literature shows how residual renal function (RKF), defined as the urinary clearance of urea and creatinine, is associated with a lower mortality risk in HD patients. The use of non-nephrotoxic contrast media during radiological procedure, may be useful for preservation of RKF in patients with chronic kidney disease not yet in haemodialysis. We describe the case of a 51-year-old male suffering from chronic kidney disease from 2018, due to a right nephrectomy for an adenocarcinoma, who was considered for an endovascular arteriovenous fistula (endoAVF) creation (WavelinQ endoAVF System, Becton Dickinson, Franklin Lakes, New Jersey, US), using Carbon Dioxide as contrast media instead of conventional iodinated ones, with optimal results. CO2 DSA permits to well recognize the patency of target vein, its connection to the perforator vein and finally the endoAVF creation without requiring supplemental iodate contrast medium. We propose, CO2 automated digital subtraction angiography (DSA) as a safer technique that could be substitutive of the standard iodinated ones, in the creation of endo AVF.

Percutaneous Creation of Hemodialysis Fistulas

Non-surgical, percutaneous, or endovascular hemodialysis arteriovenous creation represent an evolution of access creation away from traditional surgical fistulas. These fistulas are additional to surgical alternatives and published studies with the two commercially available devices suggest positive outcomes in terms of technical success, maturation, functionality, and patency. Relevant published studies are presented, and other considerations related to these new devices/procedures are also summarized.

A systematic review aggregated data and individual participant data meta-analysis of percutaneous endovascular arteriovenous fistula

OBJECTIVE

To assess the short-term and mid-term safety and efficacy of percutaneous endovascular arteriovenous fistula (pAVF) creation.

METHODS

A systematic search was implemented corresponding to the PRISMA 2020 and the PRISMA for individual participant data (IPD) systematic reviews 2015. Aggregated data from the included studies were obtained and meta-analyzed regarding both the overall pAVF efficacy and the comparison of pAVF with surgical AVF (sAVF). We performed a two-stage IPD meta-analysis for studies comparing pAVF and sAVF regarding primary and secondary patency. Primary end points included primary patency, secondary patency, and functional cannulation.

RESULTS

Eighteen studies with 1863 patients were included. The overall pAVF, primary patency, secondary patency, functional cannulation and abandonment rates were 54.01% (95% confidence interval [CI], 40.69-66.79), 87.27% (95% CI, 81.53-91.42), 79.94% (95% CI, 65.94-89.13), and 15.58% (95% CI, 7.77-28.79), respectively. The overall pAVF, technical success, maturation, reintervention per person-years and mean time to maturation rates were 97.08% (95% CI, 95.66-98.04), 82.13% (95% CI, 71.64-89.32), 0.80 (95% CI, 0.34-1.47), and 58 days (95% CI, 36.64-92.82), respectively. Secondary patency and pAVF abandonment rates where the only end points were WavelinQ and Ellipsys displayed statistically significant differences of 81.36% (95% CI, 76.15-85.65) versus 92.12% (95% CI, 87.94-94.93) and 32.54% (95% CI, 22.23-44.87) versus 11.13% (95% CI, 4.82-23.65). An IPD meta-analysis of hazard ratios for primary and secondary patency between pAVF and sAVF were 1.27 (95% CI, 0.61-2.67) and 1.25 (95% CI, 0.87-1.80), favoring sAVF. Statistically significant difference between pAVF and sAVF were solely depicted for steal syndrome relative risk of 5.91 (95% CI, 1.12-31.12) and wound infections relative risk of 4.19 (95% CI, 1.04-16.88). Plotting of pAVF smoothed hazard estimate displayed an upsurge in the probability of primary patency failure at 1 month after the intervention.

CONCLUSIONS

Although we failed to identify statistically significant differences between pAVF and sAVF regarding any of the primary end points, pAVF displayed a decreased risk for steal syndrome and wound infection. Although both the Ellipsys and WavelinQ devices displayed satisfactory secondary patency rates, Ellipsys demonstrated a statistically significant improved rate compared with WavelinQ. Additionally, and despite the borderline statistically insignificant inferior reintervention rate displayed by WavelinQ, one in three WavelinQ pAVFs resulted in abandonment. The introduction of pAVF as a treatment modality calls for standardized definition adjustment and improvement.

Technique of percutaneous closure of an endovascular arteriovenous fistula created for dialysis access

Endovascular arteriovenous fistulas (eAVFs) are a new and less invasive type of creation for dialysis access. The anastomosis for eAVFs often occurs between the ipsilateral proximal radial artery and vein or proximal ulnar artery and vein. As eAVF creations are in locations that are not traditionally used for surgical AVF creations, the question of how to approach reversal of these fistulas arises. Here we present a case of closure of an ulnar artery to ulnar vein eAVF.

Practical guide of vascular ultrasound in arteriovenous fistulae

The use of vascular ultrasound, especially with the increasing prevalence of percutaneous arteriovenous fistulas, has taken a central role as a diagnostic and therapeutic imaging procedure in vascular access creation. The current review article stresses the importance of vascular ultrasound in arteriovenous fistula, from planning to creation to maintenance. It summarises and gives practical guidance regarding sonographic criteria for vascular access procedure planning, the application of vascular ultrasound intraoperatively and during follow-up. Ultrasound education and training modalities to meet high standards of patient care in hemodialysis are presented.

Endovascular Arteriovenous Fistula Creation-Review of Current Experience

Functioning vascular access is an essential element for life-saving hemodialysis therapy. A surgically-created arteriovenous fistula has been considered the best option for many years. Recently, two manufacturers developed systems for percutaneous/endovascular creation of an arteriovenous fistula (WavelinQ and Ellipsys). We provide a review of the available experience with these systems and discuss advantages and disadvantages.

Adapting a Dialysis Service for Delivery of Percutaneous Arteriovenous Fistulas

The percutaneous arteriovenous fistula (pAVF) is an exciting and novel addition to the vascular access options available to patients with end-stage kidney disease who require dialysis. Early clinical results have been promising, with high rates of maturation and low rates of reintervention. To successfully adapt an existing hemodialysis service to include the provision of pAVF formation, it is essential to identify and align the interests of key clinical and nonclinical stakeholders. Only through strong collaboration can the service be supported. The authors provide a comprehensive overview of the planning fundamentals required, including the referral pathway, screening and clinical assessment, and practical procedural elements and considerations, as well as follow-up requirements such as cannulation, fistula surveillance, and maintenance. Key staffing requirements are highlighted, including those pertaining to vascular US screening and dialysis nurse training. A broad and structured planning approach ensures that the entire network of key stakeholder interests is included and provides a strong foundation for a compelling business plan to attract the necessary funding and managerial support for the service. The authors present a systematic framework of the essential considerations necessary to facilitate the planning, funding, and ultimately delivery of a successful pAVF service. Online supplemental material is available for this article. ^©RSNA, 2022.

Sistema percutáneo de creación de fistulas arteriovenosas en pacientes con hemodiálisis: nuestra experiencia inicial

Introducción: La fístula arteriovenosa es considerada el acceso de elección para los pacientes en hemodiálisis; en los últimos años emerge una alternativa a la creación quirúrgica de esta: la fístula arteriovenosa endovascular. Esta nueva tecnología conlleva un método menos agresivo y sin cirugía.Objetivo: Describir los datos preliminares de nuestra unidad tras la implantación de este sistema novedoso, así como su implicación para enfermería.Material y Método: Análisis descriptivo retrospectivo de las FAV-endovasculares realizadas a cinco pacientes mediante técnica percutánea. Se consideraron las características de los pacientes, de las FAV-endovasculares realizadas y la dificultad para su punción (escala EVA).Resultados: La edad media fue de 63 (47-77) años, 100% hombres, dializándose con catéter tunelizado, a 4 de los pacientes se les había realizado al menos una fístula arteriovenosa quirúrgica sin éxito. La creación de la FAV-endovascular fue exitosa en 4 de los 5 pacientes, todas con localización radio-radial. No hubo complicaciones durante el procedimiento. De las 4 FAV-endovasculares 3 precisaron intervención endovascular posterior para su maduración. La media de tiempo de maduración 4,5 (4-5) meses; las 4 continuaron permeables al año.Puntuada por 9 enfermeras experimentadas, la mediana de dificultad fue: punción inicial: 7, a partir del mes: 5 y comparada con las FAV quirúrgicas: 5.Conclusiones: La FAV-endovascular supuso un procedimiento mínimamente invasivo con menor impacto para los pacientes, elevado éxito inicial, pero precisó intervención endovascular posterior para su maduración. La dificultad para la punción fue más elevada inicialmente. La ausencia de cicatriz  supuso realizar una exploración más exhaustiva.

Percutaneous endovascular arteriovenous fistula: A systematic review and meta-analysis

Objective

Currently, percutaneous endovascular creation of arteriovenous fistula (AVF) shows excellent outcomes. However, few systematic research evidence to support clinical decision making on the benefit of endovascular AVF is available. The purpose of this study was to evaluate the efficacy and safety of endovascular AVF (endoAVF) in patients with renal failure.

Methods

We searched the Medline, Embase, Cochrane Library, and ClinicalTrials.gov databases for studies on endovascular or endovascular versus surgery for the creation of AVF. Two reviewers independently selected studies and extracted data. A systematic review and meta-analysis were performed by Review Manager 5.4 software (Revman, The Cochrane Collaboration, Oxford, United Kingdom) and Stata 15.0 (Stata Corp, College Station, TX, United States).

Results

A total of 14 case series and 5 cohort studies, with 1,929 patients, were included in this study. The technique success was 98.00% for endoAVF (95% CI, 0.97–0.99; I² = 16.25%). There was no statistically significant difference in 3 cohort studies between endovascular and surgical AVF for procedural success (OR = 0.69; 95% CI, 0.04–11.98; P = 0.80; I² = 53%). The maturation rates of endoAVF were 87.00% (95% CI, 0.79–0.93; I² = 83.96%), and no significant difference was observed in 3 cohort studies between the 2 groups (OR = 0.73; 95% CI, 0.20–2.63; P = 0.63; I² = 88%). Procedure-related complications for endoAVF was 7% (95% CI, 0.04–0.17; I² = 78.31%), and it did not show significant difference in 4 cohort studies between the 2 groups (OR = 1.85; 95% CI, 0.37–9.16; P = 0.45; I² = 59%).

Conclusion

The endovascular creation of AVF is potentially effective and safe. These important data may provide evidence to support clinicians and patients in making decisions with endovascular AVF. But further research is great necessary due to lack of randomized controlled studies.

Outcomes of Wrist-Access Deep Venous Embolization Following Percutaneous Fistula Creation: A Two-Year Single Center Experience

PURPOSE

During percutaneous arteriovenous (pAVF) fistula creation, deep venous embolization is recommended to encourage superficial venous flow development. The safety of crossing adjacent to the newly formed fistula from wrist venous access has not been established. The purpose of this study was to evaluate the safety and efficacy of antegrade deep venous embolization after creation of the pAVF.

MATERIALS

A retrospective analysis was performed of all procedural data related to pAVF creation using the Wavelinq device from October 2019 to November 2021. Patient data from the hospital information systems were collected where the venous access for fistula creation was from the wrist-access (ulnar or radial vein) and where deep venous embolization was performed after forming the fistula and crossing adjacent to the anastomosis. Thirty-nine patients were identified.

RESULTS

Twenty pAVFs were created from wrist ulnar vein access and 19 from radial vein access. The accessed veins were used for embolization of the brachial veins central to the newly created anastomosis. No pAVFs were lost by crossing adjacent to the anastomotic area to perform deep venous embolization at time of creation. There were no major complications, specifically bleeding, infection, pseudoaneurysm formation. Rates of minor complications consisted of two coil migrations to the right atrium requiring uneventful retrieval (5%). Follow-up ultrasound data showed no evidence of delayed complications.

CONCLUSION

In this single center experience crossing alongside the anastomosis of a newly formed percutaneous fistula from an antegrade venous approach was safe with no risk of loss of the pAVF.

Percutaneous Hemodialysis Fistula Creation

Two devices have been recently introduced to European Union and North American clinical practice that allow for percutaneous creation of autogenous hemodialysis fistulas (pAVF). Although there are similarities between the devices, there are many differences. Adoption of either or both technologies by an interventionalist may be determined by the individual's comfort with the device. Importantly, current and future outcomes will shape acceptance and use of these devices. This review focuses on the similarities and differences of each device, the procedures, published outcomes to date and their interpretation and other clinical considerations towards initiation of a successful pAVF program.

Endovascular Versus Surgical Arteriovenous Fistulas: A Systematic Review and Meta-analysis

Rationale & Objective

To facilitate the process of dialysis for patients with kidney failure, an arteriovenous fistula (AVF) is created using either a surgical or percutaneous approach. We sought to compare the efficacy and procedural outcomes in creating an AVF percutaneously using Ellipsys (Avenu Medical) or WavelinQ (Becton Dickinson Medical) with surgery in all patients with kidney failure requiring a permanent AVF for dialysis.

Study Design

Systematic review and meta-analysis.

Setting & Study Populations

All patients requiring a permanent AVF for dialysis.

Selection Criteria for Studies

We included studies that compared either the Ellipsys device or WavelinQ directly with surgery to create an AVF for long-term dialysis.

Data Extraction

Two reviewers independently reviewed the studies and extracted the data. Conflicts were resolved with a discussion and approval from the senior author.

Analytical Approach

Fixed-effects or random-effects models were used to pool the fixed sizes and 95% CIs based on the level of heterogeneity.

Results

There was no statistically significant difference observed between surgical AVF and endovascular AVF when comparing the primary outcomes of procedural success (OR = 1.44; 95% CI, 0.35, 5.88; P = 0.61; I2 = 0%), complications (OR = 0.28; 95% CI, 0.06, 1.46; P = 0.13; I2 = 69%), and the secondary outcomes of interest that included follow-up time (mean difference [MD] = -17.71; 95% CI, -189.53, 154.12; P = 0.84; I2 = 94%), failure rate (OR = 1.03; 95% CI, 0.21, 5.13; P = 0.97; I2 = 85%), and time to 2-needle cannulation (MD = -5.40; 95% CI, -38.88, 28.08; P = 0.75; I2 = 0%). However, a statistically significant difference was seen among the 2 groups for procedural time (MD = -54.25; 95% CI, -59.78, -48.71; P < 0.001; I2 = 98%), number of interventions needed to maintain patency (OR = 1.73; 95% CI, 1.22, 2.45; P < 0.01; I2 = 94%), and primary patency rate (OR = 0.34; 95% CI, 0.23,0.52; P < 0.001; I2 = 0%).

Limitations

The total number of studies included in this review was limited, with 3 of the 4 included studies being retrospective and only 1 being prospective. There was a lack of heterogeneity and randomization.

Conclusions

Percutaneous fistula creation using Ellipsys or WavelinQ is a unique and safe alternative with outcomes comparable to surgery. Future studies are needed, including observational studies in current clinical practice, to evaluate the efficacy and outcomes of endovascular AVF creation in clinical populations.

Devices and Techniques for Percutaneous Creation of Dialysis Arteriovenous Fistulas

Dialysis treatment for chronic kidney disease was first developed by Dr. Willem Kolff in 1943, and its availability began to grow in 1962 after which it has become a mainstay treatment for patients with chronic kidney disease. It is estimated that, in 2021, 15% of adults in the United States (∼37 million people) have chronic kidney disease, of which 661,000 individuals have renal failure, and 468,000 individuals require dialysis. There have been several advancements in dialysis treatment since its advent, most notably the creation of arteriovenous fistulas (AVFs) for venous access in 1966. In recent years, the U.S. Food and Drug Administration approved two new devices for AVF creation using a percutaneous approach. These are the WavelinQ (Becton Dickinson, New Jersey) and the Ellipsys (Avenu Medical, California) endovascular AVF (endoAVF) devices that use radiofrequency and thermal technologies, respectively, to create the AVF. Since the introduction of these technologies, several studies have shown that they are safe and effective, with favorable durability and low rate of serious adverse events. In this article, we will discuss these two devices and the techniques used for percutaneous creation of dialysis AVF as an alternative to traditional open surgical techniques.

Percutaneous arteriovenous fistula creation

The first percutaneous systems used to create an arteriovenous fistula for hemodialysis were approved by the US Food and Drug Administration in 2018 and included the Ellipsys and WavelinQ devices. Early results and longer-term studies of these catheter-based devices suggest that they offer important benefits and potentially improved outcomes in patients with appropriate anatomy. The deep communicating vein in the cubital fossa and its relationship to the proximal radial artery or proximal ulnar artery are key vascular elements of both systems. The devices differ significantly in technical design, energy source, imaging requirements, procedure times, catheters, access vessel sites, and techniques. We review the two approved percutaneous arteriovenous fistula devices, including technical considerations, selecting the appropriate patient, postoperative evaluation, interventions, outcomes, potential complications, and cannulation issues.

Pediatric hemodialysis access

Pediatric hemodialysis access is a demanding field. Procedures are infrequent, technically challenging, and associated with high complication and failure rates. Each procedure affects subsequent access and transplants sites. The choice is made easier and outcomes improved when access decisions are made by a multidisciplinary, pediatric, hemodialysis access team. This manuscript reviews the current literature and offers technical suggestions to improve outcomes.

Feasibility of Creation of an Endovascular Arteriovenous Fistula in Patients Undergoing Preoperative Vascular Mapping

Background

The first endovascular arteriovenous fistula (endoAVF) device (WavelinQ), a novel percutaneous technique of AVF creation, was approved by the Food and Drug Administration in 2018 and has been placed in a small number of United States patients on hemodialysis. It is unknown how often patients with advanced CKD have vascular anatomy suitable for WavelinQ creation. The goal of this study was to determine the proportion of patients with vascular anatomy suitable for WavelinQ creation and to assess patient characteristics associated with such suitability.

Methods

All patients referred for vascular access placement at a large academic medical center underwent standardized preoperative sonographic vascular mapping to assess suitability for an AVF. During a 2-year period (March 2019 to March 2021), we assessed the suitability of the vessels for creation of WavelinQ. We then compared the demographic characteristics, comorbidities, and vascular mapping measurements between patients who were or were not suitable for WavelinQ.

Results

During the study period, 437 patients underwent vessel mapping. Of these, 51% of patients were eligible for a surgical AVF, and 32% were eligible for a WavelinQ AVF; 63% of those suitable for a surgical AVF were also suitable for a WavelinQ AVF. Patients with a vascular anatomy suitable for WavelinQ were younger (age 55±15 versus 60±14 years, P=0.01) but similar in sex, race, diabetes, hypertension, coronary artery disease, and peripheral artery disease.

Conclusions

Among patients with CKD with vascular anatomy suitable for a surgical AVF, 63% are also suitable for a WavelinQ endoAVF. Older patients are less frequently suitable for WavelinQ.

Percutaneous Arteriovenous Fistula Creation with the WavelinQ 4-French EndoAVF System: A Single-Center Retrospective Analysis of 30 Patients

PURPOSE

To retrospectively assess the safety and efficacy of percutaneous arteriovenous fistula (pAVF) creation with the WavelinQ 4-F EndoAVF System.

MATERIALS AND METHODS

From February 2018 to June 2020, 30 pAVFs were created in 30 consecutive patients (men; age, 55.3 years ± 13.6). Of the 30 patients, 21 (70%) were already on hemodialysis using a central venous catheter. The primary outcome measures were technical success, complications, and cannulation rate. The secondary outcome measures included the number of secondary procedures needed for cannulation, maintenance time to cannulation, and pAVF survival.

RESULTS

Technical success was 100%. The adverse event rate was 6.7% (2/30), including a pseudoaneurysm of the brachial artery that developed immediately after sheath removal and an aneurysm of the anastomosis 17 days after the procedure, which was treated with a covered stent placed in the arterial side. The mean follow-up was 547 days ± 315.7 (range, 14-1,071 days). The cannulation rate was 86.7% (26/30). The mean time to cannulation was 61.3 days ± 32.5 (range, 15-135 days). The mean follow-up after cannulation was 566.2 days ± 252.7 (range, 35-1,041 days). Four pAVFs were thrombosed after cannulation, with 2 of them successfully declotted. Sixteen interventions were needed to achieve cannulation after the index procedure in 15 patients (overall, 0.53 procedures/patient). Seven maintenance endovascular interventions (following cannulation) were performed during the follow-up period in 6 patients (overall, 0.27 procedures/patient, 0.17 procedures/patient-years). For the pAVFs that were cannulated, patency was 96% at 1 year, and 82% at 2 and 3 years, according to the Kaplan-Meier survival analysis.

CONCLUSIONS

This initial experience suggests that pAVF creation is safe and can be successfully performed with high maturation and long-term patency rates. Larger-scale prospective studies are needed to validate the results.

Percutaneous Arteriovenous Fistula Creation with the 4 French WavelinQ™ EndoAVF System

BACKGROUND

Percutaneous devices for creation of native arteriovenous fistulae offer an alternative to traditional open surgical techniques. The 4 Fr WavelinQ EndoAVF System was developed as a lower profile alternative to facilitate access through smaller vessels and minimize access site complications; The current report is the original first experience of this device, assessing outcome in 120 patients followed for 6 months.

METHODS

The use of the 4 Fr WavelinQ system in three studies, EASE (32 patients), EASE-2 (24 patients), and the EU post-market clinical follow-up study (64 patients) was aggregated and analyzed. Patients were followed with duplex ultrasound at discharge and follow-up visits at 1, 3, and 6 months. Primary, assisted primary, and secondary patency rates were evaluated as Kaplan-Meier (KM) estimates and standard errors. Time to maturity and time to successful cannulation were defined as the mean ± SD days from the procedure in patients enrolled on dialysis.

RESULTS

Procedural success was achieved in 116 patients (96.7%). Primary, assisted-primary, and secondary 6-month patency rates were 71.9%±4.5%, 80.7%±4.1%, and 87.8%±3.3%, respectively. Time to maturity averaged 41±17 days. Time to successful cannulation averaged 68±51 days. Device-related serious adverse events were reported in 3/120 patients (2.5%) and procedure-related serious adverse events occurred in 7/120 patients (5.8%). Arterial or venous access complications were not reported in any of the patients. Access circuit reinterventions were performed in 23 patients (19.2%), split between those performed for EndoAVF maturation (13/120, 10.8%) and maintenance (11/120. 9.2%).

CONCLUSIONS

Percutaneous creation of native dialysis fistulae with the 4 Fr WavelinQ EndoAVF System is safe and effective, with favorable durability and a low rate of serious complications and reinterventions through 6-month follow-up. Utilization of the 4F device allows for percutaneous fistula creation between the radial artery and radial vein or the ulnar artery and ulnar vein. These findings suggest that the 4 Fr device is a useful percutaneous alternative to open surgical AVF or endovascular AVF with larger-bore devices.

Research Priorities for Percutaneous Arteriovenous Fistula Creation in Patients with End-Stage Renal Disease: Proceedings and Recommendations from a Multidisciplinary Research Consensus Panel

Recently developed endovascular techniques to create percutaneous arteriovenous fistulas are an alternative to surgical arteriovenous fistula creation, although there is currently a lack of high-level evidence regarding their creation, maturation, utilization, and long-term function. Recognizing this, the Society of Interventional Radiology Foundation sponsored a Research Consensus Panel and Summit for the prioritization of a research agenda to identify and address the gaps in current knowledge.

Multicenter European real-world utilization of VasQ anastomotic external support device for arteriovenous fistulae

OBJECTIVE

To evaluate the outcomes of arteriovenous fistulae (AVF), created with VasQ external support device under standard clinical practice across three vascular access clinics.

METHODS

This multinational, retrospective study evaluated prospectively collected clinical outcomes of both forearm and upper arm brachiocephalic AVF (BCAVF) created using the VasQ device. Fifty-one AVF patients were pooled from three different vascular access centers in Germany, Italy, and Spain. Postprocedure outcomes were assessed by flow measurement with ultrasound examination in all centers. Primary failure, usability, patency, and intervention rates during the study period were evaluated.

RESULTS

Fifty-one VasQ devices were implanted during 37 forearm (36 radiocephalic and 1 ulnar-basilic AVF) and 14 BCAVF procedures. The study population comprised mostly males (73%) and Caucasians (82%), with a mean age of 62.5 years (range, 38-84 years) and mean body mass index of 29.2. One patient died owing to access-unrelated reasons, and one patient was lost to follow-up without AVF assessment after its creation. From the remaining 49, 3 patients had a follow-up of less than 4 weeks and were excluded from maturation, primary failure, and dialysis initiation analysis (because those factors could not be evaluated yet), leaving 46 patients in this evaluation. Maturation was achieved in 91% of patients. The primary failure rate was 9%. A primary patency rate of 77% was observed at 6, 12, and 18 months. The secondary patency rate was 91% at 6 months, and 85% at 12 months and 18 months. Both primary patency and secondary patency did not differ statistically when comparing forearm AVF with BCAVF (P > .25). Successful cannulation was achieved in 86% of patients (32/37) requiring dialysis with a median time from creation to cannulation of 46 days. Of those patients, the functional patency rate was 94%. Five patients underwent seven interventions to maintain or restore patency or functionality, with an overall rate of 0.248 interventions per patient-year.

CONCLUSIONS

AVFs created with VasQ external support device demonstrated promising patency and functionality outcomes in multicentric real-world setting across the two most commonly used anatomic locations.

A Comparison of Outcomes Between Open and Endovascular Arteriovenous Access Creation for Hemodialysis

OBJECTIVE

Preliminary outcomes for percutaneous endovascular autogenous access (endoAVF) have shown promising results; however, comparisons with surgical cohorts in dialysis populations are lacking. This study compares autogenous arteriovenous access created with the EverlinQ endoAVF system with accesses created by conventional surgical technique with respect to functional and patency related outcomes.

METHODS

This is a multicenter, retrospective review of autogenous arteriovenous accesses entered into a prospective database. Patients receiving radiocephalic, brachiocephalic, or endoAVF arteriovenous accesses between 2014 -2019 were included. Autogenous access maturation, primary patency, secondary patency, steal syndrome, and re-interventions were collected and analyzed using standard statistical and survival analyses.

RESULTS

A total of 369 accesses were created during the study period, including 61 endovascular accesses, 171 radiocephalic accesses, and 137 brachiocephalic accesses (median follow-up 17 months; range 1 - 71 months). Maturation failure at the end of follow-up was 27±6%, 27±5%, and 18±4% for endovascular, radiocephalic, and brachiocephalic accesses, respectively (p =.049 for brachiocephalic vs. endovascular accesses). Primary patencies at 12 and 24 months were 42±5% and 32±7% for endovascular accesses, 43±4% and 24±4% for radiocephalic accesses, and 42±4% and 29±4% for brachiocephalic accesses (p=.906). Secondary patencies at 12 and 24 months were 68±6% and 60±7% for endovascular accesses, 75±3% and 67±4% for radiocephalic accesses, and 91±3% and 81±4% for brachiocephalic accesses (p=.006 for brachiocephalic vs. endovascular accesses). There were no statistically significant differences in ischemic steal syndrome (3.3%, 4.1% and 8.0%; p=.229) or total reinterventions/year (1.0±3.1, 0.9±1.8, and 1.2±1.8; p=.289) for endovascular, radiocephalic, or brachiocephalic arteriovenous accesses, respectively.

CONCLUSIONS

EndoAVF compare favorably with respect to maturation and patency compared with surgically created accesses in a real-world cohort. Outcomes and reintervention rates are similar to conventional radiocephalic arteriovenous accesses, but are inferior with respect to patency and maturation to brachiocephalic accesses.

Endovascular arteriovenous fistulas- are they the answer we haven't been looking for?

INTRODUCTION

Surgically created arteriovenous fistulas are the accepted gold standard for the establishment of hemodialysis access in patients requiring dialysis. However, primary and maturation failures may limit their usage. Recent advances in endovascular technology have resulted in the creation of devices for endovascular arteriovenous fistula formation. These devices may offer an additional or alternative approach to fistula formation in patients with end-stage kidney disease.

AREAS COVERED

This review describes the limitations of surgical arteriovenous fistulas and the endovascular devices currently available. The review covers initial trial data and subsequent studies examining their use.

EXPERT OPINION

Early results achieved with endovascular fistula formation are encouraging. Current limitations of this technology include anatomic suitability and a high rate of re-interventions required to establish maturity. Greater uptake of the technology will also require a review of long-term outcomes in larger patient cohorts.

Initial Outcomes Following Introduction of Percutaneous Arteriovenous Fistula Program with Comparison to Historical Surgically Created Fistulas

BACKGROUND

Recently, there has been an abundance of encouraging data regarding the creation of percutaneous arteriovenous fistulas. Despite promising data regarding their clinical maturation, a paucity of data exists which provides direct comparison between percutaneously created AVFs (pAVF) and open surgically created AVFs (sAVF). This study has 2 primary objectives: First, to compare clinical outcomes of pAVFs to sAVFs, with emphasis on clinical maturation and frequency of postoperative interventions to facilitate maturation. Second, to contribute toward the evidence-based incorporation of the pAVF procedure into the hemodialysis access algorithm.

METHODS

A single-center retrospective review was performed on all consecutive patients undergoing surgically created brachiocephalic arteriovenous fistula (BC-AVF, sAVF group) from January 1, 2018 to December 31, 2018 and Ellipsys-created percutaneous arteriovenous fistula (pAVF group) from January 1, 2019 to December 31, 2019. Comparative analysis between groups was performed.

RESULTS

A total of 24 patients underwent Ellipsys-created pAVF with mean age of 56.7 ± 22.6 years (12 males [50%], 12 females [50%]) and 62 patients underwent surgically created BC-AVF with mean age of 62.5 ± 13.2 years (32 males [52%], 30 females [48%]). Both the pAVF and sAVF groups had comparable mean operating times (60 ± 40 vs. 56 ± 25 min, P = 0.67) and frequency of procedural technical success (23 [96%] vs. 62 [100%], P = 0.28), respectively. The pAVF group had a lower clinical maturation rate (12 [52%] vs. 54 [87%], P = 0.003) and a higher primary failure rate (9 [39%] vs. 6 [10%], P = 0.003) when compared to the sAVF group. The pAVF group had an increased overall rate of undergoing a postoperative intervention (18 [78%] vs. 13 [21%], P< 0.001), as well as an increased number of total postoperative interventions (1.1 ± 0.9 vs. 0.3 ± 0.6 interventions, P< 0.001) compared to the sAVF group. Percutaneous transluminal angioplasty of the juxta anastomotic segment was the most prevalent postoperative intervention performed in the pAVF group and occurred at a significantly increased frequency when compared to the sAVF group rate (13 [57%] vs. 5 [8%], P< 0.001).

CONCLUSIONS

In our single-center retrospective review, patients undergoing Ellipsys-created pAVF in the first year following introduction of percutaneous endovascular had inferior rates of clinical maturation and underwent more postoperative interventions when compared to historical patients undergoing surgically created BC-AVF. Outcome discrepancies compared to previously reported Ellipsys data demonstrate a need for further studies examining the practical translatability of the pAVF.

Anatomic suitability for commercially available percutaneous arteriovenous fistula creation systems

OBJECTIVE

The Food and Drug Administration recently approved two percutaneous arteriovenous fistula creation systems: the Ellipsys vascular access (EL) system and WavelinQ EndoAVF (WQ) system. Although the initial clinical trials of each system have demonstrated a high success rate, little detail on anatomic suitability was provided. We sought to determine the real-world applicability of the EL and WQ systems by studying them in a single representative cohort.

METHODS

All patients receiving a first-time arteriovenous access consultation at a single Veterans Affairs institution underwent extensive vein mapping of the bilateral upper extremities. Anatomic suitability was assessed in accordance with the manufacturer's instructions for use (IFU), and clinical usability was determined using additional published anatomic guidelines. The suitability for radiocephalic fistula (RCF) creation was also assessed. To estimate how often these systems would be used in practice, a clinical algorithm was created, with a preference for RCF creation, followed by percutaneous arteriovenous fistula (pAVF) creation, surgical fistula creation at the elbow, and, finally, graft placement.

RESULTS

During the study period, 116 upper extremities were measured in 58 male patients. Per the IFU, the rate of extremity suitability was 93% and 52% for the WQ and EL systems, respectively (P < .0001). In the same population, 32% of the extremities had acceptable anatomy for RCF creation. The overall clinical usability of these systems using more recent published guidelines was 55% for the WQ system and 44% for the EL system (P = .09). The usability of both pAVF systems was most limited by the size of the deep perforating cubital vein. The proximity of the antecubital perforator vein and proximal radial artery additionally limited EL usability. Based on the clinical algorithm, initial access creation would have been RCF creation for 31% of the cohort, followed by the WQ (32%), the EL (23%), surgical fistula creation at the elbow (18%), and graft placement (17%).

CONCLUSIONS

Anatomic suitability was greater for WQ than for EL when considering only the IFU. Once the full requirements for pAVF creation were considered, we found no significant differences in usability between the two systems. Anatomic analysis showed that pAVF creation can constitute a substantial part of a hemodialysis access practice.

The role of surgery for assisted maturation after endovascular and percutaneous arteriovenous fistula creation

Even in the best of circumstances, a significant number of patients will require adjunctive endovascular and/or surgical revision prior to achieving functional patency after endovascular or percutaneous AVF creation, at least within the United States. This rate appears to be higher after percutaneous AVF than after endovascular AVF, although because published reports of the former are mostly derived from American experience and those of the latter derived from experience outside the United States, it is unclear whether these differences are due to the technique itself or cultural and/or anatomic differences in dialysis access practices and patient populations. If arterial inflow is poor, this should be corrected first. When flow is adequate (perhaps 900 cc/min) but no single vein is cannulatable, a dominant suitable vein can be superficialized or transposed. If no suitable vein is dominant (most accurately assessed by using an intraoperative flowmeter), the best vein can be used, with or without occlusion of the other veins or reimplantation into the brachial artery. Finally, if the original anastomosis remains the sole supply to the cannulated vein, the original fistula has achieved assisted primary maturation (and assisted primary patency continues), while if a new arteriovenous anastomosis has been constructed, the original fistula has failed. We point out that for this reason as well as to best utilize the upper arm for later access, endovascular and percutaneous AVFs should be constructed and maintained within an atmosphere where both surgeons and non-surgeons work together on the overall access plan.

Initial 6-month quality review of a percutaneous endovascular arteriovenous fistula program

Background:

Percutaneous arteriovenous fistulas have recently proven successful alternatives to surgical arteriovenous fistulas with encouraging initial results. The Ellipsys Endovascular Arteriovenous Fistula System utilizing ultrasound and thermal energy has recently received approval for use in the United States. At the University of New Mexico, we developed an integrated service between Vascular Surgery, Interventional Radiology, and Interventional Nephrology for percutaneous arteriovenous fistulas utilizing Ellipsys.

Methods:

We performed a retrospective chart review of the initial 6 months (January 1st 2019 to July 1st 2019) of 18 percutaneous arteriovenous fistula placements to evaluate our initial technical success rate, the number of arteriovenous fistulas meeting maturation characteristics or use in dialysis, and to identify areas for quality improvement.

Results:

Initial technical success was achieved in 17 out of 18 arteriovenous fistulas (94.4%). Three patients did not report for any follow-up at the end of the initial 6 months. Of the remaining patients, 7 out of 15 were using their arteriovenous fistulas or meeting maturation characteristics at the end of the study (46.7%). Patient loss to follow-up/no-show (16.7%), patient not yet requiring hemodialysis (27.8%), and poor post-surgical maturation and/or need for additional maturation procedures (55.6%) were the predominate reasons for non-use. We identified improved coordination of care, early intervention, and outpatient dialysis center education as the primary areas of focus for quality improvement.

Conclusion:

Initial technical success rate of percutaneous arteriovenous fistulas placement was comparable to published studies. Early and aggressive secondary angiographic interventions of arteriovenous fistulas failing to meet cannulation requirements, improved coordination of post-operative care, and outpatient dialysis center education appear to be the primary targets for quality improvement.

Creating percutaneous radiocephalic arteriovenous fistulas at the wrist

BACKGROUND

The first arteriovenous fistulas were created at the wrist more than 60 years ago. Basic surgical construction techniques remain unchanged with mobilization and repositioning of the vessels followed by a sutured anastomosis. We used the Ellipsys device to construct percutaneous radiocephalic-arteriovenous fistulas at the wrist and report the results.

METHODS

Data were reviewed retrospectively for all patients who had a percutaneous radiocephalic-arteriovenous fistula created during a 6-month period. Each individual underwent ultrasound vessel mapping in addition to physical examination. When a radiocephalic-arteriovenous fistula was feasible and a communicating vein ⩾ 2 mm in diameter was noted in the distal forearm along with a radial artery ⩾ 2 mm, a percutaneous radiocephalic-arteriovenous fistula was considered and reviewed with the patient.

RESULTS

Four individuals met the criteria to consider a percutaneous radiocephalic-arteriovenous fistula and all elected to have the procedure performed. Ages were 54-85 years. Three were diabetic and one was female. All percutaneous radiocephalic-arteriovenous fistulas were technically successful. Two individuals had not yet started dialysis therapy. Successful and repetitive cannulation for the two individuals with catheters was initiated at 4 and 8 weeks post procedure. The two pre-dialysis patients had physiologic arteriovenous fistula maturation (6 mm vein diameter and >500 mL/min flow) at 4 and 12 weeks. There were no procedural or late complications and none required intervention. Follow-up was 8-23 months (mean 16 months).

CONCLUSION

The success of these percutaneous radiocephalic-arteriovenous fistulas suggests that use of the Ellipsys device will be applicable at the wrist in selected patients where appropriate vessel sizes and configurations are found.

Endovascular versus surgical creation of arteriovenous fistula in hemodialysis patients: Cost-effectiveness and budget impact analyses

Objectives:

The aim of the present study was to perform cost-effectiveness and budget impact analyses comparing endovascular arteriovenous fistula creation to surgical arteriovenous fistula creation in hemodialysis patients from the National Healthcare Service (NHS) perspective in Italy.

Methods:

A systematic literature review has been conducted to retrieve complications’ rates after arteriovenous fistula creation procedures. One study comparing endovascular arteriovenous fistula creation, performed with WavelinQ device, to the surgical approach through propensity score matching was preferred to single-arm investigations to execute the economic evaluations. This study was chosen to populate a Markov model to project, on a time horizon of 1 year, quality adjusted life years and costs associated with endovascular arteriovenous fistula (WavelinQ) and surgical arteriovenous fistula options for both cohorts of incident and prevalent hemodialysis patients.

Results:

For both incident and prevalent hemodialysis patients, endovascular arteriovenous fistula creation, performed with WavelinQ, was the dominant strategy over surgical arteriovenous fistula approach, showing less cost and better patients’ quality of life. Compared to the current scenario, progressively increasing utilization rates of WavelinQ over surgical arteriovenous fistula creation in the next 5 years in incident hemodialysis patients are expected to save globally 30–36 million euros to the NHS.

Conclusion:

Endovascular arteriovenous fistula creation performed with WavelinQ could be a cost-saving strategy in comparison with the surgical approach for patients in hemodialysis. Future studies comparing different devices for endovascular arteriovenous fistula creation versus the surgical option would be needed to confirm or reject the validity of this preliminary evaluation. In the meantime, decision-makers can use these results to take decisions on the diffusion of endovascular procedures in Italy.

KDOQI Clinical Practice Guideline for Vascular Access: 2019 Update

The National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI) has provided evidence-based guidelines for hemodialysis vascular access since 1996. Since the last update in 2006, there has been a great accumulation of new evidence and sophistication in the guidelines process. The 2019 update to the KDOQI Clinical Practice Guideline for Vascular Access is a comprehensive document intended to assist multidisciplinary practitioners care for chronic kidney disease patients and their vascular access. New topics include the end-stage kidney disease "Life-Plan" and related concepts, guidance on vascular access choice, new targets for arteriovenous access (fistulas and grafts) and central venous catheters, management of specific complications, and renewed approaches to some older topics. Appraisal of the quality of the evidence was independently conducted by using a Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach, and interpretation and application followed the GRADE Evidence to Decision frameworks. As applicable, each guideline statement is accompanied by rationale/background information, a detailed justification, monitoring and evaluation guidance, implementation considerations, special discussions, and recommendations for future research.

WavelinQ created arteriovenous fistulas versus surgical radiocephalic arteriovenous fistulas? A single-centre observational study

Purpose:

Devices to permit percutaneous endovascular arteriovenous fistula formation have recently been introduced into clinical practice with promising initial evidence. As guidelines support a distal fistula first policy, the question of whether an endovascular arteriovenous fistula should be performed as an initial option is introduced. The aims of this study were to compare a matched cohort of endovascular arteriovenous fistula with surgical radiocephalic arteriovenous fistulas.

Materials and methods:

Using data from a prospectively collected database over a 3-year period, a matched comparative analysis was performed.

Results:

WavelinQ arteriovenous fistulas (group W, n = 30) were compared with radiocephalic arteriovenous fistulas (group RC; n = 40). Procedural success was high with 96.7% for group W and 92.6% for group RC. Primary patency at 6 and 12 months was greater in group W (65.5% 6mo and 56.5% 12mo) compared to group RC (53.4% 6mo and 44% 12mo) ( p = 0.69 and 0.63). Mean primary patency was significantly lower for RC (235 ± 210 days) vs W (362 ± 240 days) ( p < 0.05). Secondary patency for group W was 75.8% and 69.5% at 6 and 12 months, respectively. Secondary patency for RC was lower at 66.7% and 57.6% at 6 and 12 months, respectively.

Conclusion:

Outcomes of WavelinQ arteriovenous fistulas in this series are similar to published results. When compared to a contemporaneously created group of surgical fistulas, WavelinQ demonstrated superior outcomes. These data would support that WavelinQ endovascular arteriovenous fistulas may be considered as a first option in the access pathway particularly if vessels at the wrist are absent or less than ideal.

Early cannulation of percutaneously created arteriovenous hemodialysis fistulae

INTRODUCTION

The optimal vascular access for most dialysis patients is an arteriovenous fistula and the recognized appropriate process of care for the chronic kidney disease patient is to have the access in place ready for use when renal replacement therapy is required. Unfortunately, as a result of multiple barriers, most patients start dialysis with a catheter and many experience multiple interventions. The recent advent of the percutaneous arteriovenous fistula may offer at least a partial solution to these problems. The purpose of this study was to report of the results of early cannulation of the percutaneous arteriovenous fistula.

MATERIALS AND METHODS

Early cannulation, less than 14 days post creation, was performed in 14 cases in order to avoid an initial catheter or continued use of a problematic catheter for dialysis. Immediately post access creation, blood flow ranged from 491 to 1169 mL/min (mean = 790 mL/min). Ultrasound was used to map potential cannulation sites prior to use. Cannulation was performed using plastic fistula cannulas.

RESULTS

Early cannulation was successful in this cohort of cases except for one cannulation complication. Dialysis treatments were otherwise uncomplicated. Primary patency at 3, 6, and 12 months was 76%, 76%, and 66%, respectively. Assisted primary patency for the same intervals was 100%, 100%, and 91%, respectively. Cumulative patency was 100% at all three-time intervals.

CONCLUSION

The results of this study suggest that the possibility of successful early cannulation with a percutaneous arteriovenous fistula can be considered as an additional factor in making this access a reasonable alternative for a surgically created arteriovenous fistula in appropriate patients.

Early cannulation of percutaneously created arteriovenous hemodialysis fistulae

INTRODUCTION

The optimal vascular access for most dialysis patients is an arteriovenous fistula and the recognized appropriate process of care for the chronic kidney disease patient is to have the access in place ready for use when renal replacement therapy is required. Unfortunately, as a result of multiple barriers, most patients start dialysis with a catheter and many experience multiple interventions. The recent advent of the percutaneous arteriovenous fistula may offer at least a partial solution to these problems. The purpose of this study was to report of the results of early cannulation of the percutaneous arteriovenous fistula.

MATERIALS AND METHODS

Early cannulation, less than 14 days post creation, was performed in 14 cases in order to avoid an initial catheter or continued use of a problematic catheter for dialysis. Immediately post access creation, blood flow ranged from 491 to 1169 mL/min (mean = 790 mL/min). Ultrasound was used to map potential cannulation sites prior to use. Cannulation was performed using plastic fistula cannulas.

RESULTS

Early cannulation was successful in this cohort of cases except for one cannulation complication. Dialysis treatments were otherwise uncomplicated. Primary patency at 3, 6, and 12 months was 76%, 76%, and 66%, respectively. Assisted primary patency for the same intervals was 100%, 100%, and 91%, respectively. Cumulative patency was 100% at all three-time intervals.

CONCLUSION

The results of this study suggest that the possibility of successful early cannulation with a percutaneous arteriovenous fistula can be considered as an additional factor in making this access a reasonable alternative for a surgically created arteriovenous fistula in appropriate patients.

Early experience and observations in endovascular dialysis fistula re-intervention

In recent years, new emerging technology has allowed the endovascular creation of dialysis fistulas in the proximal forearm without the need for open surgery. Two such systems currently exist, and evidence to date has demonstrated high rates of technical success in fistula creation, high rates of dialysis functionality, and low rates of re-intervention using both systems. Whilst early trial data has demonstrated lower rates of re-intervention to maintain patency compared to surgical fistulas, endovascular re-interventions are still required to maintain functionality. The endovascular fistula (endoAVF) typically exhibits a shared drainage pattern and is morphologically distinct from the surgical fistula and patterns of failure observed often differ to what has been traditionally encountered. A fresh approach and understanding is therefore required and here we share our observations and experience of endovascular re-intervention in endoAVF created with the Wavelinq system.

Patient selection, education, and cannulation of percutaneous arteriovenous fistulae: An ASDIN White Paper

End-stage kidney disease patients who are candidates for surgical arteriovenous fistula creation commonly experience obstacles to a functional surgical arteriovenous fistula, including protracted wait time for creation, poor maturation, and surgical arteriovenous fistula dysfunction that can result in significant patient morbidity. The recent approval of two endovascular devices designed to create a percutaneous arteriovenous fistula enables arteriovenous fistula creation to be placed in the hands of interventionalists, thereby increasing the number of arteriovenous fistula providers, reducing wait times, and allowing the patient to avoid surgery. Moreover, current studies demonstrate that patients with percutaneous arteriovenous fistula experience improved time to arteriovenous fistula maturation. Yet, in order to realize the potential advantages of percutaneous arteriovenous fistula creation within our hemodialysis patient population, it is critical to select appropriate patients, ensure adequate patient and dialysis unit education, and provide sufficient instruction in percutaneous arteriovenous fistula cannulation and monitoring. In this White Paper by the American Society of Diagnostic and Interventional Nephrology, experts in interventional nephrology, surgery, and interventional radiology convened and provide recommendations on the aforementioned elements that are fundamental to a functional percutaneous arteriovenous fistula.

Preoperative assessment for percutaneous and open surgical arteriovenous fistula creation in patients for haemodialysis

Preoperative assessment prior to surgical arteriovenous fistulas (AVFs) including ultrasound-guided mapping has been shown to have beneficial effects on their immediate success as well as early outcomes. This has led to their wide acceptance and adoption however clinical practice criteria is variable and is reflected in variabilities in practice. When transposing this to percutaneously created endovascular AVFs (endoAVFs), variable preoperative assessment criteria could equally result in variable practice and potentially subsequent and expectant outcomes. We aimed to review literature on reported validated methodologies and workflows of preoperative assessment for surgical AVF creation as reported in highest levels of available evidence, specifically randomized controlled trials. Published practice recommendations and guidelines on best clinical practice as well as systematic reviews and meta-analyses of published studies were also reviewed. Data on practice methodology from identified trial publications and protocols was collated and a summative narrative synthesis was carried out which compared these methodologies to additional assessments that may be required when targeting assessment for percutaneous endoAVF formation, based on our units experience as part of an international multicentre trial. In this review we present a brief overview of published literature and guidelines and propose a unified and uniform workflow for preoperative assessment for surgical AVFs and endoAVFs to aide clinical and imaging practice.

A systematic review, meta-analysis, and meta-regression of the efficacy and safety of endovascular arteriovenous fistula creation

OBJECTIVE

The percutaneous endovascular approach to arteriovenous fistula (AVF) creation is a minimally invasive alternative to surgical AVF creation. This systematic review and meta-analysis aimed to investigate the efficacy and safety of endovascular AVF creation in patients with end-stage renal disease.

METHODS

This study conformed to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. An electronic search was performed on major databases to identify relevant articles. Meta-analysis of proportions and meta-regression were conducted.

RESULTS

Seven studies totaling 300 patients were included, of which four evaluated the everlinQ (TVA Medical, Austin, Tex) and three employed the Ellipsys (Avenu Medical, San Juan Capistrano, Calif) systems. The overall technical success rate was 97.50% (95% confidence interval [CI], 94.98-99.31%; I² = 0.00%; P = .487). The 90-day maturation rate was 89.27% (95% CI, 84.00-93.66%; I² = 21.29%; P = .283), and the 6-month patency and 12-month patency were 91.99% (95% CI, 87.98-95.35%; I² = 0.00%; P = .780) and 85.71% (95% CI, 79.90-90.71%; I² = 0.00%; P = NS), respectively. The overall procedure-related complication rate was 5.46% (95% CI, 0.310-14.42%; I² = 81.21%; P = .000). Meta-regression was conducted on the pooled rates of technical success and complication, showing that age, diabetes, white race, hypertension, on dialysis, and body mass index were not significant sources of heterogeneity.

CONCLUSIONS

Current endovascular AVF systems appear to be effective and safe. However, given the lack of head-to-head comparative analyses with surgical AVF creation, superiority cannot be established.

Clinical hemodialysis experience with percutaneous arteriovenous fistulas created using the Ellipsys® vascular access system

INTRODUCTION

The aim of this study is to report our clinical hemodialysis experience using a percutaneous arteriovenous fistula (pAVF) created with the Ellipsys® vascular access system. This pAVF device creates a permanent AVF anastomosis between the proximal radial artery (PRA) and the deep communicating vein (DCV) in the proximal forearm.

METHODS

The medical records of all patients with a pAVF were retrospectively reviewed. The clinical data analyzed included reliability of pAVF use, quality of dialysis, rate and success of puncture, and pAVF related complications, along with incidence of subsequent interventions.

FINDINGS

Between May 2017 and November 2018, 34 patients had a pAVF created with technical success in 33 patients (97%). Twenty-eight out of 34 (82%) patients had successful two-needle cannulation within 10 days to 6 weeks after pAVF creation. The mean Kt/v was 1.6 (1.2-2) and the average recirculation was 10%. Fifteen patients (44%) needed no further access intervention. Twelve patients (35%) required an additional procedure to assist maturation of the pAVF in order to facilitate puncture. The average blood flow measured at the brachial artery, before the first cannulation, was 850 ml/min. From causes unrelated to the procedure, four patients died during the follow-up study. Two patients required revision to a surgical AVF. None of the pAVFs developed aneurysmal degeneration steal syndrome, or high access flow related issues.

DISCUSSION

The Ellipsys® pAVF offers a safe and functional vascular access for hemodialysis. Advantages included prompt access maturation, avoidance of high flow AVFs, and a simple nonsurgical procedure with high patient satisfaction. Functional outcomes are equivalent and likely better than surgical fistulas. There appears to be less aneurysmal degeneration and need for future re-intervention. Objective dialysis parameters indicate excellent quality of hemodialysis for the patient.