Renal Interventions 10 – EU

February 2024 Issue 10 www.renalinterventions.net

In this issue:

VentureMed Flex Vessel Prep System page 04

CX Vascular Access Preview

Continued on page 2

Vandana Dua Niyyar page 10

Updates from Paris Vascular Insights page 13

Education of patients and parents imperative for the future of paediatric dialysis access

New option for chronic kidney failure patients emerges as Ozempic trial for renal treatment concludes Ozempic (Novo Nordisk) is a oncedaily injection with US Food and Drug Administration (FDA) approval for use as a preventative treatment for strokes and heart attacks in type 2 diabetic patients. Recently, however, the FLOW study has shown that the semaglutide-based drug may also have applications as a preventative treatment for chronic kidney disease (CKD).

The study had its preliminary stages ended early due to positive data showing signs that semaglutide would be effective when used to treat patients with both type 2 diabetes (T2D) and CKD—as confirmed by an independent data monitoring committee—but Novo Nordisk will remain blind to these results until the study officially concludes in August of 2024.

An article published in January 2023 in Nephrology Dialysis Transplantation by Peter Rossing (Complication Research, Steno Diabetes Center Copenhagen, Herlev, Denmark) et al outlined the rationale, design and baseline data of the FLOW trial. The authors stated that CKD is a common complication of T2D, and that glucagon-like peptide-1 receptor agonists (GLP-1RAs) can both “improve glycaemic control and lower body weight in people with T2D” and “reduce the risk of cardiovascular (CV) events in those with high CV risk.” According to Rossing et al, “GLP-1RAs might also have kidney-protective effects.”

One of the reasons that they decided to undertake this study was that, to date, “data have mostly been derived from CV outcome or glycaemic control trials featuring populations not selected for CKD and/ or with kidney disease events as secondary outcomes”. What the FLOW study aims to do then, is look specifically at populations that have both T2D and CKD, so that definitive answers can be found regarding the effectiveness of semaglutide drugs—such as Ozempic—in preventing the progression of CKD. FLOW is a randomised, double-blind, parallel-group, multinational, phase 3b trial

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“You have to have a balanced approach.”

This was the core message from Vincent Rowe (University of California Los Angeles Health, Los Angeles, USA) during his presentation on paediatric haemodialysis access at the most recent VEITHsymposium (14–18 November, New York, USA). “There is still a lot of catheter use” in paediatric patients receiving dialysis care, Rowe stated, “[but] fistula first still remains the best approach for children, even though it’s changing for [adult patients]”. However, overall, more balance is needed for children, due to the fast transplant rates for paediatric renal dysfunction patients, he argued.

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here are several key differences between dialysis for adult and paediatric patients; Rowe outlined aetiology, barriers, technique—for both catheters and fistulas—and the impact of transplantation. With regards to the aetiology, Rowe stated that it can be “quite different in children”, with more congenital issues. “We’re not dealing with the diabetes, hypertension, [or] polycystic kidney disease like we see in our adult [patients].” Instead of these issues, paediatric patients are more frequently bludgeoned with glomerular nephropathies and congenital issues, as Rowe put it.

One of the main barriers that Rowe has encountered during his practice, he revealed, were the patient and parental responses to proposed treatments. “I’d say [that] we’re ready to move forward to your access” and he would be met with resistance from both the patients and their parents. The children would respond by arguing that they don’t want fistula access, as they are “afraid of needles”, think that fistulas “look ugly”, or because they “won’t be able to wear jewellery [or] play sports”. Turning to the parents for a decision, Rowe said that what he found “really surprising” was that, rather than making a choice, they would instead say that they “are not sure” and that they “don’t know what’s best” for their child. One response he found surprising was when parents would say that “it’s really [the child’s] decision”. The position he often found himself in, he said, was one where “it’s 12- or 13-year-olds making the decision” regarding their dialysis access, a decision which is sometimes being informed by, in Rowe’s expe-

rience, aesthetics and fears. Due to this, Rowe said that “patient and parent education is, I think, very important”.

Rowe then moved on to another of the key differences that he had mentioned at the beginning of his presentation; technique, or more specifically, the techniques applied to catheter use in paediatric patients. Rowe initially highlighted the higher prevalence of catheter use in general: “We looked up 101 patients,” he said, “and over 78% had previous catheters. A lot of them had previous subclavian catheters—over 40%—and a lot of them have the catheter on the same side as the fistula, so it was a real issue.” Rowe continued by examining data from an article published in American Journal of Kidney Disease, which he said showed that, in a survey from over 27 countries, with over 552 patients, “you could see, as the age went down, [there were] a lot more catheters, and it continued even up into the teens.”

Moving on from the statistics of catheter use, Rowe asked the audience “what about the techniques applied in catheter use?” Answering his own question, he stated that “they’re very different”. With a picture of a pre-curved catheter, he explained that there are none that are available for use in paediatric patients. After discussing why this is the case concerning catheter providers, he found that “there are not enough children getting dialysis to make a market” for them to develop paediatric catheters. There are also very few lengths of catheters for children availaContinued on page 2

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Education of patients and parents imperative for the future of paediatric dialysis access

Continued from page 1 ble, with catheter French sizes being a particular problem area, according to Rowe. With very little guidance available, Rowe recalled, “I just said, ‘well, okay, let me see if I can figure something out’”. He stated that he would “take the age of the child as a guideline for catheter size” and would then adjust accordingly. “If it was a bigger child, then I would go up a size, if it was a smaller child, I went down in size and that’s all I could really figure out.” There are now, however, “better evaluations based on kilogrammes”, he stated, but he lamented that he did not “have that [resource] 10 years ago”.

Another variation in physicians’ use of catheters in paediatric patients is the use of micro-puncture kits, Rowe highlighted. “Some of these children,” he explained, “are so small, the wire [from the micro-puncture kit] will head from the internal jugular all the way down to the iliac vein”.

He said that clinicians need to watch it very carefully, because the wires are very long—as are the catheters used to introduce them—so they have to be very careful when putting these catheters into children. He also added that “because there’s no pre-curve, most of the time, you will need a secondary counter incision to make the catheter work and to avoid kinking”.

The biggest difference in fistula placement technique that Rowe highlighted was “vasospasm and intraoperative [vein] mapping”. One issue that he encountered was inaccuracy with preoperative vein mapping, as “the preoperative vein mapping and vascular lab showed one thing, and then once [the patients] were on the table, it shows something else”, meaning that remapping intraoperatively via ultrasound was often needed. This can also present further issues and delays, according to Rowe, as—once remapping was complete—he would then have to return to the patients’ parents and inform them that “actually, I can do a fistula at the wrist”. The “back and forth” that frequently followed to obtain consent led to delays, even “with the patient at the table”. Rowe also added that he “[doesn’t] really use tourniquet occlusion; it doesn’t help at all and otherwise it’s pretty standard that kids can tolerate two stage transpositions and tolerate it on the femoral vein”.

In an article published in Journal of Vascular Surgery in 2014 by Rowe et al, the outcomes with arteriovenous fistulas in a paediatric population were investigated. In 101 patients, Rowe stated that “our patency was very good up to four years, as well as our secondary patency”. Expanding on the factors that impacted the results of the study, Rowe said that: “When we looked at the differ-

ences based on all of our patients, age seemed to be somewhat of a factor, but we didn’t see much for sex or aetiology, and also weight didn’t seem to matter as well—which I thought would, but it really didn’t—and actually, having a catheter on the same side, even a subcutaneous catheter, didn’t make a difference with any of the patency, which was good to see.” A similar study published in Pediatric Nephrology in 2020 also explored predictors of arteriovenous fistula patency, which found similar results regarding to factors that impacted fistula patency. “Age was a key factor in terms of when these patients could be cannulated,” Rowe averred, “and they showed a nice correlation between age and decannulation”, as if “the child was older when they got their access, they could be cannulated sooner”.

The final difference that Rowe discussed was the impact of transplantation. “As you can see,” he began—referring to the data on a slide in his presentation—“the waiting time [for transplants] has been less than 200 days for quite a while”. This, to Rowe, had the biggest impact on “how I treated these kids, because they were going to get a transplant”. The disparities that can impact the wait time for transplantation “seem to be changing” for the better, reducing the difference between different demographics of patients, according to Rowe. This means that not only are the disparities reducing, but that wait times are “coming down for everybody” he stated. Due to this, Rowe said that he “tried to use” this low transplantation wait time as a guideline for which type of access—catheter or fistula—he would use for his paediatric dialysis patients. “If I have a young child,” he said, “I’m going to probably lean toward a catheter, because they’re going to get transplanted in less than 200 days. In a child who is a little older, that may end up in the adult units, I’m going to go with the fistula.”

Concluding his presentation, Rowe, who is also a member of the Charing Cross International Symposium chronic limb-threatening ischaemia (CLTI) Executive Board, summarised the key points that he had raised; “haemodialysis access is slightly different [in children]”. There is still a lot of catheter usage, he pointed out, and stated that patient and parent education is very important.

Conveying his final thoughts, he noted that “the fistula first principle still remains for kids—even though it’s changing for adults—and you have to have a balanced approach”.

“We looked up 101 patients and over 78% had previous catheters. A lot of them had previous subclavian catheters—over 40%—and a lot of them have the catheter on the same side as the fistula, so it was a real issue.”

New option for chronic kidney failure patients emerges as Ozempic trial for renal treatment concludes Continued from page 1

comparing semaglutide with matched placebo. Both arms received the standards-of-care when the trial began in 2019, including renin-angiotensin-aldosterone system (RAAS) blockade for delaying the progression of CKD in participants with CKD and T2D. The authors described the methods, stating that: “Participants were randomly assigned 1:1, using a central interactive web response system, to receive once-weekly subcutaneous injections of semaglutide 1mg or visually identical placebo, in addition to the maximum labelled orPeripheral tolerated dose of a RAAS blocking agent (unless contraindicated or not tolerated).” They also stated that they permitted the use of SGLT2i, and that “randomisation was stratified by use at baseline”.

The researchers employed an eight-week dose escalation regimen at the start of treatment, with “dose escalation (as tolerated) from 0.25mg/week for four weeks to 0.5mg for four weeks, followed by a maintenance dose of 1mg/week throughout the remainder of the treatment period,” as they stated in their article. “Participants were trained in handling the pen injector when dispensed for the first time,” they continued, “and instructed to inject the trial product subcutaneous once-weekly in the abdomen or thigh. Training was repeated at week four, week 26 and yearly.” Rossing et al also stated that, if a participant were to experience unacceptable adverse events, extensions of dose escalation intervals, dose reductions and treatment pauses are allowed at the investigators’ discreC tion. They also permitted optimisation of glucose-lowering, CKD and CV disease standard-of-care medications, in M accordance with local practice guidelines.

Y Once enrolment was completed, the authors had a total of 3,534 participants that had been randomised to treatCM ment. These participants had a mean age of 66.6 years MY (standard deviation [SD] 9), 69.7% were male and 65.7% were white. The mean glycated haemoglobin (HbA1c) was CY 7.8% (SD 1.3) or 61.5mmol/mol (SD 14.1) and a high proportion of participants (68.6%) had a baseline HbA1c >7%. The CMY mean baseline diabetes duration was 17.4 years (SD 9.3), K body mass index was 32kg/m2 (SD 6.3) and systolic and diastolic blood pressure were 138.6mmHg (SD 15.8) and 76.4mmHg (SD 10), respectively.

Speaking to Renal Interventions, Saravanan Balamuthusamy (Tarrant Nephrology Associates, Fort Worth, USA) shared his views on the FLOW trial and the use of medications such as Ozempic for renal treatments. “Optimal glycaemic control is essential in preventing end organ damage in diabetes,” he stated, adding that “GLP-1RAs have been shown to improve [cardiovascular] outcomes in addition to improving glycaemic control in prior studies. Diabetes is the most common cause for kidney disease and hence decreasing the progression of kidney disease with GLP-1RAs in addition to standard of care could be a major milestone in disease mitigation.” His final thoughts were that “one can expect to see updates in recommendations and standards of care if the FLOW trial is a positive study demonstrating incremental benefits in reducing CKD progression in addition to RAASi and SGLT2 agents.”

Editor-in-chief: Nicholas Inston | Editorial Board: Ziv Haskal, Stephen Hohmann, Robert Jones Publisher: Stephen Greenhalgh | Content Director: Urmila Kerslake | Global Commercial Director: Sean Langer | Editor: George Barker georgeb@bibamedical.com Editorial contribution: Jocelyn Hudson, Will Date, Éva Malpass, Jamie Bell, Bryan Kay | Design: Terry Hawes, Wes Mitchell Advertising: Rav Pankhania rav@bibamedical.com Subscriptions: subscriptions@bibamedical.com | News or advertising queries: Tel: +44 (0)20 7736 8788 Published by: BIBA News, which is a subsidiary of BIBA Medical Ltd BIBA Medical, Europe, 526 Fulham Road, Fulham, London, SW6 5NR, United Kingdom Tel: +44 (0) 20 7736 8788 | BIBA Medical, North America, 155 North Wacker Drive, Suite 4250, Chicago, IL 60606, United States Tel: +1 708-770-7323 Printed by: Print Tech Solutions. Reprint requests and all correspondence regarding the newspaper should be addressed to the editor at the United Kingdom address. © BIBA Medical Ltd, 2024. All rights reserved.

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Renal Interventions February 2024 – Issue 10

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CONTROVERSIES

CHALLENGES

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Vascular & Endovascular

Controversies Update Aortic Controversies

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Peripheral Arterial Controversies

Venous & Lymphatic Controversies

Carotid & Acute Stroke Controversies

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Vascular Trauma Controversies

23–25 APRIL 2024 TUESDAY-THURSDAY NEW VENUE, ExCeL LONDON, UNITED KINGDOM

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Programme Highlights

Vascular Access CONTROVERSIES

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• Podium First: IN.PACT AV Access – the latest outcomes Tuesday, 23 April • Great Debate: Endovascular AVFs are a failed experiment Tuesday, 23 April • Roundtable: The international approach to vascular access problems Tuesday, 23 April • Vascular Access Workshop: Including real-life ultrasound sessions with patients Wednesday, 24 April

VASCULAR ACCESS EXECUTIVE BOARD:

NICHOLAS INSTON

KATE STEINER

45 YEAR LEGACY OF VASCULAR EDUCATION CONTINUES EDUCATION

INNOVATION

EVIDENCE

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Advertorial

This advertorial is sponsored by VentureMed Group

The FLEX vessel prep system: working to extend time and improve outcomes in AV access maintenance

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rteriovenous (AV) access is challenging and dialysis is hard on the body and the mind. It causes physical aches, pains, and changes in the body that rob patients of energy and strength.1 When access becomes blocked, regaining blood flow can be painful, delay life-saving treatment, and lead to complications for patients over the long-term. The repetitive occurrence of access dysfunction is a persistent issue that challenges physicians and frustrates patients. Extending the time between interventions likely improves the quality of life for dialysis patients.

Percutaneous transluminal balloon angioplasty (PTA) is the standard procedure for stenoses in arteriovenous fistulas (AVFs) and grafts. This procedure will usually provide a successful immediate result. However, the lasting patency is less than optimal requiring patients to undergo frequent interventions.2 New devices, treatments, and therapies are key to making needed advancements in this disease state.

of the lesion. Once the lesion is crossed, the treatment element is re-sheathed and advanced again through the lesion, rotated approximately 30–90 degrees before the treatment element is re-deployed and the retrograde pullback described above is repeated based on operator preference. The micro-surgical blades of FLEX VP exert a consistent force of approximately 1atm on the vessel wall to deliver precise, parallel, micro-incisions addressing a wide range of morphologies.

Positive, real-world clinical data The FLEX AV Registry study is a multicentre, prospective, observational registry (FLEX AV) enrolling haemodialysis patients scheduled to undergo PTA of their AV fistula or graft due to clinical or haemodynamic abnormalities.

One-hundred and fourteen patients across eight clinical sites were treated with the FLEX VP prior to PTA. No serious adverse events were reported. Among the 82 patients who underwent FLEX VP with plain balloon PTA, target John Aruny Novel non-balloon vessel prep solution lesion primary patency at 12 months was 44.8% The FLEX vessel prepTM system (FLEX VP) with an average freedom from target lesion is designed to treat AV access dysfunction. revascularisation of 256.6 days. Target lesion It creates micro-incisions that release the primary patency and freedom from target circumferential tension and improves vessel lesion revascularisation for AV fistula cases compliance and lumen gain with the inten(n=57) were 49% and 267.3 days, respectively. tion to reduce the acute need for high-presIn cases treating AVF cephalic arch stenosis sure PTA and associated barotrauma that may (n=23), 12-month target lesion primary patency be a stimulus for restenosis.2 was 59.7% with an average freedom from target Robert Shahverdyan The FLEX VP is an endovascular medical lesion revascularisation of 267.7 days.3 device indicated for use prior to PTA to facilitate dilaFor reference, the FLEX VP results are favourable to tion of stenoses in the femoral and popliteal arteries and the literature for treating fistulas with PTA alone. There is treatment of obstructive lesions of native or synthetic a large variation of target lesion primary patency results AV dialysis fistulae. The FLEX VP is also indicated for from 0% to 47.2%. The literature also shows cephalic arch treatment of in-stent restenosis of balloon expandable lesions have documented 12-month primary patency and self-expanding stents in the peripheral vascula- ranging from 0% to 33.9%. In addition, it has been ture. The proximal portion of each treatment element reported that the incidence of re-intervention in cephalic strut includes a 0.010-inch micro-surgical blade. Once arch lesions is up to 3.5 times per year.4 the device is advanced past the lesion, the treatment element is unsheathed and expanded, and the cathe- Clinical utilisation with the experts ter is slowly drawn back, allowing the micro-surgical Commenting on his experience with FLEX VP, John blades to independently engage in the lesion and create Aruny (Musc Health, Dialysis Access Institute, Orangethree parallel, continuous micro-incisions, with a depth burg, USA) had this to say: “I have worked with FLEX for of approximately 0.010 inches along the entire length several years as part of the growing body of evidence in

FLEX Vessel PrepTM System Protective Struts for continuous Engagement

Atraumatic Tip Excellent crossing

February 2024 – Issue 10

Treatment Element FLEXes and contours for continuous engagement

• 6Fr; .014” or .018” guidewire (OTW)

• Braided shaft design for consistent deliverability

• 3 working lengths – 40cm (AV Access), 75cm & 120cm (FemPop)

• Atraumatic tip for enhanced trackability & crossing profile

Braided Reinforced Shaft consistent deliverability

3 Precision Blades .010” consistent depth of cut

Treatment Element Actuator

Sheath Actuator

FLEX Vessel PrepTM Retrograde Pullback

clinical trials. FLEX offers a safer procedure than standalone high-pressure PTA, with no adverse events. Most recently, we published on the 12-month outcomes, which demonstrated sustained patency across most patients, and what we saw in challenging cephalic arch patients was even more impressive. Twelve-month patency for AVF lesions was 49% and cephalic arch showed 59.7% patency. Vessel Prep in AV access with long micro-incisions may also provide an attractive alternative to drugcoated balloons (DCBs) for AV access repair where cost is a key concern.”

Robert Shahverdyan (Asklepios Klinik Barmbek, Hamburg, Germany) also explored his experience with the FLEX VP: “I have used this device in my practice to treat dysfunctional AV access, and there is no other device like it due to its mechanism of treatment. It is very easy to learn and use, and takes up very little space in our lab, with two sizes available for AV access. FLEX VP creates micro-incisions along the entire length of the stenoses in significantly shorter procedure time as compared to prolonged balloon angioplasty, hence also reducing the radiation exposure time, if performed under X-ray and not ultrasound guidance only. The benefits are many, including reducing the necessity to use high or ultra-high-pressure balloons prior to using DCBs. These micro-incisions also look to potentially increase the effectiveness of drug application into the vessel wall via the use of DCBs, and seem to even reduce the pain for patients, which they experience during the traditional PTA procedures. I am impressed with the ability to clearly see the device and its instant effect on the lesion under ultrasound guidance.”

Looking forward in AV access maintenance Chronic kidney disease (CKD) has emerged as one of the most prominent causes of death and suffering in the 21st century.5 As end-stage renal disease grows, due in part to the rise in risk factors, such as obesity and diabetes mellitus, the number of haemodialysis patients impacted

by AV access dysfunction will continue to increase. The good news is that medical device innovations like FLEX VP are created to help advance patient care so that patients maintain their lifesaving haemodialysis therapy.

References 1. Dialysis is not your life, The Power to redefine your life while on dialysis, Fred Hill, 2020 Reset inc.

2. Aruny et al., Longitudinal micro-incision creation prior to balloon angioplasty for treatment of arteriovenous access dysfunction in a real-world patient population: 6-month cohort analysis. Hemodialysis International. 2023:1.

3. Aruny J, Hull JE, Yevzlin A et al. Longitudinal micro-incision creation prior to balloon angioplasty for treatment of arteriovenous access dysfunction in a real-world patient population: 12-month cohort analysis. J Interventional Nephrol. (2023).

4. Beathard GA, Jennings WC, Wasse H et al. ASDIN white paper: Management of cephalic arch stenosis endorsed by the American Society of Diagnostic and Interventional Nephrology. J Vasc Access.

24, 358-69 (2023).

5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9073222/#bib1

“FLEX VP offers a safer procedure than standalone high-pressure PTA, with no adverse events. Most recently, we published on the 12-month outcomes, which demonstrated sustained patency across most patients, and what we saw in challenging cephalic arch patients was even more impressive.” John Aruny

Point of View

Point of View

Koen van der Bogt & Joris Rotmans

Dynamic AVFs: A promising solution in the making

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ver since Leiden University’s graduate Willem Kolff created the first dialysis machine in 1943, the vascular access community has been struggling to provide adequate vascular access solutions that enable a durable flow that is high enough for running dialysis sessions of about 350ml/min.

Since the 1960s, we routinely create arteriovenous fistulas (AVFs) that run a constant supraphysiological blood flow of typically 1000ml/min or higher. Due to high flow, vascular access patients experience diminished hand perfusion, suffer from the effects of compensatory intimal hyperplasia, stenosis, and angioplasties, may experience aneurysmal degeneration, spend significant time on dialysis wards for compression of needling sites, and undergo negative cardiac remodelling due to constantly elevated cardiac output.

Vascular access complications—mainly stenosis and thrombosis—require approximately 1.5 interventions per patient per year to maintain functional vascular access. The corresponding healthcare costs relating to these interventions range between US$8,000–32,000 per patient per year. In the USA alone, total costs related

to vascular access management surmount US$3 billion per year. Until now, no comprehensive solutions have been available to diminish these sideeffects while protecting the vascular access and, above all, the patient.

Some nine years after Kolff ’s discovery, the southern part of the Netherlands suffered a major flooding, leading to almost 2,000 casualties and 72,000 people seeking evacuation. It was due to a perfect storm; there was a king tide in combination with a strong north-western storm, driving up the water against the dikes and ultimately leading them to break through.

The entire south-western part of the Netherlands was flooded. From then, Delft University graduate Johan van Veen, an engineer working at the state department of infrastructure and water management, lead the creation of the Delta Works flood protection system. This system of dynamic dykes only closes in case of danger, while normal water flow, including movements of animal species, is left unaffected under normal circumstances.

Humbly building further on this Dutch heritage, our group—with experts from Leiden and Delft from the fields of vascular

More information needed for vascular access registries to be used effectively Speaking to Renal Interventions, Maarten Snoeijs (Maastricht University Medical Centre, Maastricht, The Netherlands), discussed his presentation at the Hamburg Dialysis Access symposium (8–9 September, 2023 Hamburg, Germany) which explored the possibilities that would be provided by a vascular access registry, the issues that can arise when trying to implement registries, and the impact on patient outcomes that a registry such as this could have.

surgery, nephrology, and biomedical engineering—has set out to bundle our forces to improve the quality of life of vascular access patients. This aim is the driver for the creation of the dynamic AVF, essentially providing vascular access only when the patient needs it. The prototype of the dynamic AVF consists of several patented parts: A dynamic valve, a cable, and an actuator. A narrow piece of expanded polytetrafluoroethylene (ePTFE) graft is anastomosed between an artery and a target vein, essentially creating a side-toside anastomosed AVF. The valve mechanism can then be placed over the piece of graft, while the cable runs to a distant subcutaneous plane where the actuator is implanted. The actuator, and thereby the valve, may be activated non-invasively by an external magnet that can be placed on the skin.

With this non-invasive steerable device, blood flow can be optimised before dialysis, while a return to physiological venous flow can be established towards the end of the dialysis. The width of the ePTFE graft is chosen so that it is wide enough to provide enough force to fully close and open while being narrow enough to prevent a dead space when closed. By doing so, the risk of thrombosis will likely not be increased as compared to current vascular access solutions—around 35% in grafts and 11% in autologous AVFs. The return to physiological flow, as enabled by the dynamic AVF, may offer a significant decrease in turbulence for over 150 hours per week, as compared to current AVFs and arteriovenous grafts (AVGs). This high turbulent flow is a main driver for intimal hyperplasia, stenosis, and thrombosis, as well as the consequent bulk of interventions to treat this.

Therefore, a normalisation of flow outside the dialysis sessions should significantly decrease the number of (often painful) reinterventions to treat stenosis and thrombosis. Moreover, this will lead to a considerable decrease in societal costs.

Currently, 5% of patients experience complaints of distal ischaemia because of the preferential flow to the AVF or AVG. This number may normalise with the dynamic AVF as in between dialysis sessions, arterial flow will run towards the hand, without interference from the AVF.

THE FIRST POINT THAT SNOEIJS WAS keen to highlight was that, whilst there is a dialysis registry, The Netherlands does not have a specific dialysis access registry. Despite this, he still feels that the dialysis registry is useful as an insight into vascular access in The Netherlands. “What we do have in The Netherlands is a dialysis registry. All the patients who have renal replacement therapy are in the registry—so that’s transplants, peritoneal dialysis, and haemodialysis—and for the haemodialysis patients, the type of vascular access is registered every three months.” He continued by stating that, with this information, “it is possible to see how The Netherlands [performs] compared to other countries with similar registries with regards to fistula use, dialysis catheter use, and we also have the opportunity to see how the different dialysis units within the country compare with each other, and that is quite interesting, because there’s a large variation in practice between countries—we know that from previous publications—but also within the country.”

“Sweden has a beautiful registry, but this requires a lot of effort and work by the dialysis nurses to maintain.”

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Beyond immediate benefits, a normalisation of blood flow during most of the non-dialysis time will offer a period of rest for the heart. A staggering one third of end stage kidney failure patients suffer from heart failure. It has already been shown that a fistula leads to left ventricular hypertrophy, and that the abandonment of an AVF leads to a decrease in left ventricular mass. Therefore, the dynamic AVF may offer cardiac protection by diminishing the cardiac burden of continuous high flow, hopefully minimising the already high cardiac morbidity and mortality in dialysis patients.

Most importantly, there is much to gain for the patient. A realistic fear of debilitating or even life-threatening bleeding complications, especially in aneurysmal AVFs (some 20%), is a significant burden for the patient. This fear may be socially invalidating. Moreover, the prevention of bleeding from needling sites requires additional time in the hospital, presenting another social impairment. These factors together hamper home dialysis in many cases. The dynamic AVFs ability to titrate blood flow could address these concerns, making home dialysis a more viable option for many patients.

In its preclinical phase, the dynamic AVF presents a ground-breaking solution to vascular access-related complications.

Animal studies are underway, paving the way for a true vascular access-on-demand system that could transform the landscape of dialysis care. To enable timely clinical translation, we have initiated a spinoff company by the name of XS Innovations.

XS Innovations has recently won the Dutch Research Council’s Venture Challenge, strengthening our continuous push for a better quality of life for dialysis patients.

Koen van der Bogt is a vascular surgeon at Haaglanden Medical Centre (The Hague, The Netherlands) and Leiden University Medical Centre (Leiden, The Netherlands).

Joris Rotmans is professor of internal medicine at Leiden University Medical Centre (Leiden, The Netherlands).

Disclosures: Joris Rotmans is co-founder of XS Innovations, president of the Vascular Access Society and a consultant for Xeltis, Koen van der Bogt is co-founder of XS Innovations.

Snoeijs does, however, feel that there is “room for improvement.” His main issue is that, whilst useful information is collected by published observational research—it was able to show that 20 to 30% of fistulas that are placed are never being used, because they fail, and there are more patients who require additional interventions before the access can be used—ideally, this information would be collected in a vascular accesses registry. “I presented some data from an observational cohort study within the country,” Snoeijs stated,” that showed how many interventions are needed for getting the access working, maintaining a functional access, [as well as] the variation between centres, but [that data] required a lot of effort from a PhD student to collect.” The key issue, he feels, is finding “a balance between the level of detail in the registry with the administrative workload.” “Sweden has a beautiful registry,” Snoeijs avers, “but this requires a lot of effort and work by the dialysis Continued on page 8 Issue 10 – February 2024

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Haemodialysis Access

VEITHsymposium

Haemodialysis access session offers routes to improved outcomes for patients At the 2023 VEITHsymposium (14–18 November, New York, USA), the final day featured a dedicated programme entitled “Improving outcomes in haemodialysis access”, which was made up of five sessions, each covering a different area of haemodialysis access and featuring both presentation and panel discussions led by key opinion leaders in the field.

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he day began with a presentation from Karl Illig (FLOW Vascular Institute, Houston, USA), who outlined the lessons he learned from his experience with a lack of trial management. Illig stated that after joining an institute with “no clinical trial experience at all [and] no full-time trial coordinator”, he ended up with “two arteriovenous (AV) access companies mad at [him]” due to issues with data follow-up.

After an extensive correction process to fix the issue—which was “ultimately successful”, Illig stated that he felt he had learnt from his experience, continuing to share what he had learned so that others may avoid the same “research screw-ups”. The key points that he outlined are as follows; firstly, do not trust people who have not got any experience running trials, no matter what they say, as it will not end happily.

Second, read what you will be working with—Illig categorised these as four separate things: the initial protocol, the data entry forms, the adverse event forms, and the trial event forms. The third thing that Illig emphasised was that you cannot conduct trials without a full-time, trained coordinator, who has access to all medical records (MRs) and picture archiving and communication systems (PACs), and is committed to being present for all consent, procedure, and all follow-up visits. His next point was that you have to insist that “the company knows your weaknesses, such as access to corporate dialysis unit data, absence of PACs, and so on” and that, if needed, you should have this confirmed in writing, so that you cannot be “tripped up by this”, as Illig put it. He also listed several points that the primary investigator (PI) needs to do, including creating “trial visit forms” to be used at each visit that help ensure all necessary questions are asked, making sure you do not enrol a high number or participants until the system definitely works, follow each patient personally, and several other key points.

His final point, however, was simple; “if you mess up and you start getting ‘nastygrams’ […] pay attention to those.”

The morning continued with a presentation titled “Does preoperative vascular mapping matter before access creation?” that was given by Charmaine Lok (Toronto General Hospital, Toronto, Canada). Seemingly, the question had an easy answer, as the first slide showed several memes—an amusing captioned picture that is spread widely online, especially through social media—that simply said “yes, of course!” Lok did explore this

February 2024 – Issue 10

as the presentation continued though, expanding more on why it was important; it allows for the detection of arterial and venous pathology, as well as the collection of vascular data that can influence access creation, such as size, location, patency, distensibilty and much more. Despite this, however, Lok did warn against 100% reliance on evidence gleaned from preoperative vascular mapping. Some issues that she said to bear in mind ranged from “who is doing the ultrasound” to “unnecessary delays”. The main point was that the data gained from vascular mapping cannot be the only guiding factor but must be taken in context with the wide range of other factors that can impact outcomes. Lok referred to this as “a tight rope between evidence and real-life practice”. The rest of her presentation covered the reasons that not all patients receive preoperative vessel mapping—some studies have found no benefit of preoperative mapping in addition to a clinical exam, along with some risk factors benefitting more from preoperative mapping than others—the limitations of current evidence, new data that has been collected, and finally, her own thoughts on the topic. Lok stated that she felt that “everyone should have a good physical exam and history”, as it allows for the detection of obvious limitations, if any are present, and that there are “very few people [who] do not need vessel mapping.” She also added that she feels “the person creating the [AV] access should be the one doing the vessel mapping” and that “ultrasound at the time of surgery appears ideal, and should be done in all patients, if it is feasible.”

The politics of haemodialysis Terry Litchfield (Access Solutions, Deerfield, USA) began the next session with

her presentation, “Current landscape of legal enforcement in the vascular access world”. During this presentation, she highlighted the new guidelines that the Office of Inspector General (OIG) has published recently, stating that “this is for small and big practices, so it is a great resource”. She also expanded on how physicians can tell if they are being investigated by the OIG. “Your billing staff is likely going to receive a request for medical records for more than one patient,” she said, adding that “the requests never say OIG, they never say CMS [Centers for Medicare & Medicaid Services], it’s usually a Medicare intermediary or the QIC [qualified independent contractor]. There are also special audits called comprehensive error rate testing (CERT), recovery audit contractors (RAC) and zone programme integrity contractors (ZPIC), but they don’t ever explain what they are.” When encountering these requests, Litchfield made it abundantly clear what steps physicians must take. “It is really important that your billing team knows to alert you, if any of these letters come in. Your healthcare attorney should be notified immediately.” She finished by saying that “vascular cases are targets for the OIG,” so physicians need to “really be aware of the legal environment, know the rules regarding compliance and create a culture of compliance in your practice.”

The future of dialysis technology Alexander Yevzlin (Azura Surgery Center, Madison, USA) delivered a talk titled “Initial clinical experience with a novel ultrasound system: feasibility trial update”. During this presentation, which served as an update on a trial sponsored

by Sonavex to evaluate the feasibility of a new ultrasound system, Yevzlin expanded

“Data gained from vascular mapping cannot be the only guiding factor but must be taken in context with the wide range of other factors.”

Charmaine Lok on the aims of the new device, which was developed to improve the speed at which fistulas can be evaluated, in order to reduce the dependence on catheters and the amount of time that patients have to use them prior to fistula maturation. The main reason for the development of this new ultrasound system, he said, was that “catheters are inherently bad and very expensive, and they kill people, because nature did not intend for us to have a connection between the germs that live in the outside world and the centre of our hearts.” In order to remove this risk, he stated, we need to reduce the reliance on catheters and move dialysis patients onto permanent access solutions as soon as possible, but in order to do so, issues with fistula maturation need to be overcome.

To ensure that fistulas have matured, they need to be evaluated “sooner rather than later”. Yevzlin confirmed that “there is no doubt that ultrasound helps with

this, but unfortunately, most dialysis patients are not happy having to see a separate specialist, and who can blame them? They have a very difficult life.

They’re a slave to this machine. They feel miserable three days a week at least.

And so, it’s no surprise that they don’t show up to their ultrasound appointment.” To resolve this issue, Yevzlin stated that there was a need to remove the issues created by separate clinics for ultrasounds and dialysis. “The idea of this technology,” he explained, “is to support the major delays that are caused by non-compliance and the other factors, like transportation and all this other stuff by creating a one-stop shop right in the dialysis unit here when they have to show up, and doing the ultrasound there. The problem with that, initially, is that ultrasonographers do not just show up randomly on dialysis units, and ultrasound is quite difficult— in its traditional form—to use. It requires special training.”

To overcome this roadblock, the novel ultrasound system has been developed to simplify the process via the use of a bioresorbable implant—placed during fistula creation—that communicates with the transducer, so that all the user needs to do is place it above the implant and the rest of the ultrasound is automated, meaning that “it can be done by anybody,” according to Yevzlin. “In fact,” he adds, “all you have to do is take a transducer, put it on top of the fistula and it does everything for you, [it] requires no skill whatsoever.” The last benefit that Yevzlin highlighted was that, as the data can be remotely accessed thanks to its cloud connectivity, “those who are making decisions about whether the fistula needs an intervention or needs to be cannulated” can do so in a timely manner.

Meeting the challenges Jason Wagner (Sarasota Vascular Specialists, Sarasota, USA) gave a talk in the final session titled “Optimising dialysis access strategies in the geriatric and bariatric population”. To begin with, Wagner highlighted that part of the issue with the current access strategies is that most of them were created for patients that were both young and eligible for transplantation. Now, however, the patient populations have changed, meaning that they are on average “older and bigger”. With this patient population, he continued, the goal is “bespoke access”; access strategies that have been tailored for each patient. This takes into account social factors for geriatric patients, such as living situations, support networks, and differing levels of “functional independence”, and anatomic and physiologic factors for bariatric patients, such as vessel depth, abdominal adipose deposition, and metabolic factors. He ended his talk with what he felt were the important considerations; if a patient is geriatric, bariatric, or both, a proactive “catheter-last” approach can be successful, along with early referrals, a joint approach from nephrologists and haemodialysis/peritoneal dialysis nurses, and a “thoughtful and protocoled consideration of the patient’s needs”.

Charing Cross Preview

CX 2024 controversies programme to draw in global voices to ensure better delivery of vascular access in the right way This year’s 2024 Charing Cross (CX) Symposium (23–25 April, London, UK) will feature debates on the success of endovascular arteriovenous fistulas (AVFs) alongside patient involvement and vascular access, and renal intervention sessions, among much more. The programme aims to further debate surrounding controversies in several fields and open conversations on the development of more conclusive evidence within vascular access practice.

M

ore focused and robust, evidence-based guidelines, according to one of the Vascular Access Exextive Board Members and Renal Interventions editor-in-chief Nicholas Inston (University Hospitals Birmingham, Birmingham, UK), are essential for betterment of the field of vascular access.

During a recent preview for the CX 2024 programme—which was broadcast live from the CX Studio on Thursday 26 October 2023—he stated that “[vascular access] is a huge disease area throughout the world; it is incredibly exciting, but in many areas we do not have the evidence, we do not necessarily know what is the best thing to do. The guidelines are out there, but they are vague, so that is why it is so good to have controversies this year. This is an area where we don’t always know what should be done”. He thinks that the CX Symposium is the perfect venue to address this, as “[there] is a lot based on expert opinion, and we get [the experts] together at CX; the whole thing is set up to have those debates, have people at the mic saying what they do, and at the end of this, hopefully we can agree”.

When asked what he felt the highlights of this year’s vascular access and renal interventions debates were, Inston said: “One of those debates is about endovascular AVFs, or device-created AVFs. In the last few years, we have found that we have gone from a surgically created AVF, to creating fistulas with devices. There are two major devices at the moment that we use, and I do not think we know the right way to use those[…] I do not know if that is the right way compared to surgical fistulas, because we have not really done those studies yet, so we are having a huge debate.”

The fact that there have been no randomised studies between surgical and endovascular AVFs was cited as one of the main reasons for his eagerness for this debate in particular.

“These devices[…] are brought in because otherwise we would miss out on a great technology that is coming through, but if we do not actually try and compare these with our gold standards are, how do we know what is going on? So, what we are going to do, rather than just present data from observational studies, we are going

to throw it open and have a debate about whether or not this is the right thing to do, and whether or not this is a big experiment in terms of what we are doing [regarding] treatments.”

Sticking with the theme of controversies, the title of this debate is “Endo AVFs are a failed experiment”, which Inston feels will help spur discussion. “That is the motion. You do not have to agree with it, but you can come along and debate it.

We hope the audience will have their own views, and what we are trying to promote here is strong views and getting people presenting those strong views at the microphone.”

Fellow Vascular Access Exextive Board Member Kate Steiner (East and North Herts NHS Trust, Stevenage, UK), when asked the same question, felt that “one of the high points is going to be that we now have the workshop up and running, and it is going to be much bigger this year. During the workshop, we are going to have some edited cases for discussion, where you really have a great opportunity to learn from the experts. This is going to be a great opportunity for some really good learning and sharing from people who are experts in their field, on difficult areas where, like Nick has said, there is a lot of technology out there now, but where do we use it?

Where is it best applied? Where do we really see the benefit for our patients?”

Another aspect of the programme that Steiner highlighted in the preview was the session planned on drug-coated balloons (DCBs). “We have a really good section on DCBs planned. We have level one evidence for DCB use in arteriovenous (AV) access. But I think it is fair to say that, overall, if you look at the evidence, it is very mixed,” she said about the planned session. “So where do we use them?

Where are they best applied? We have the paclitaxel-coated devices, which have been around for a while now, and now we have the new player, sirolimus, entering into the scene. So where will that fit? We have a great session presenting the current evidence, and also, some of the new trials which are evolving as well, and how they are going to fit and answer some of these really difficult questions, which we face in our practices every day; what do you use and when do you use it?”

A true benefit of CX is the fact that it is “an international symposium,” as Inston puts it. Having seen the differences internationally, in patient populations, treatments and “ways of doing things”, he feels that it is crucial to have “everyone in the audience from around the world, which CX does”, so that there is a global forum

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to discuss guidelines, debate their validity, and decide what the right thing is for practices and patients alike.

Towards the end of their section of the livestream, Inston addressed the importance of renal interventions and how it is essential that it is not overlooked. “It is the whole package of [kidney] care, so what we are going to do a lot of this year [at CX] is look at the renal vessels, renal denervation, nutcracker syndrome, the renal artery, aneurysms—they are all things that on a day-to-day basis, are rare, but a lot of us get dragged into [doing] and do not really know what to do”. As a final question, Inston was asked if renal denervation was back, after an apparent decrease in popularity, to which he replied “well, we are going to find out”.

The Vascular Access Masterclass is set to take place on the morning of Tuesday 23 April, followed by a session on renal intervention the same afternoon, with a hands-on workshop set to take place on Wednesday 24 April.

“It is the whole package of [kidney] care, so what we are going to do a lot of this year is look at the renal vessels, renal denervation, nutcracker syndrome, the renal artery, aneurysms—they are all things that on a day-to-day basis are rare, but a lot of us get dragged into [doing] and do not really know what to do.” Nicholas Inston

Clockwise from top left: Dittmar Böckler, Stephen Greenhalgh, Kate Steiner and Nicholas Inston

Issue 10 – February 2024

8

Staff Education

Hamburg Dialysis Access Symposium

More education for cannulating staff needed to ensure advances in dialysis access Dialysis access has seen an enormous multiplication of options for dialysis patients; specialised fistulas, endovascular fistulas, and new graft materials.

This has brought the focus onto allied health members that carry out cannulation in the dialysis unit, namely nurses and technicians. Yet, this poses challenges such as identifying what kind of fistula does a patient have, how do they make it ‘cannulatable’, what is their graft material, and what is their direction of flow, all of which represent skills that may need further development to give a safe patient experience and make access last longer.

T

his was the message from Dirk Hentschel (Brigham and Women’s Hospital, Boston, USA) when he spoke to Renal Interventions at the most recent Hamburg Dialysis Access symposium and Masterclass (8–9 September 2023, Hamburg, Germany) about what he feels is needed to ensure that dialysis patients are receiving the best possible standard of care whilst under the care of dialysis units.

“If you look at it, [there are] 10,000 dialysis units or so in the USA, with tens of thousands of nurses, and then tens of thousands of technologists, who actually have the day-to-day contact with the patients,” Hentschel stated. The problem arises, however, when you try to introduce the new technologies that are being developed, because, as he put it, “we’re creating all these new devices and accesses, yet they may not be usable,” because the training to match is not being introduced alongside the technology.

The solution, Hentschel feels, lies in education. “VASA [Vascular Access Soci-

Continued from page 5

Maarten Snoeijs

February 2024 – Issue 10

ety of America] is working on organised collaboration with allied health members—nurses, technologists, and physician assistants—that are in the dialysis units to carry the concepts that we’re all working on at the moment into the unit.” The issue that needs addressing, he averred, is that most technologists, technicians and nurses “look at a catheter and they connect, but they have no idea if it’s a symmetric catheter, if it’s a split catheter, or a step catheter. What that means is they feel they have to reverse the lines, and this could be bad for the patient, but if they have a symmetric catheter, it’s not bad for the patient, but that knowledge is often not there”.

That, according to Hentschel, is something that VASA is working on, with a specific committee that looks at the allied health education. “We’re going to visit the ANNA [The Association of Nephrology Nurses of America],” he said, “and so we hope that that will blossom kind of into a broader, vascular access-specific effort that maintains this line of communica-

nurses to maintain. That is the difficult thing, at least in The Netherlands, as we [have tried] to include some more items in the national registry, but this met some resistance due to the administrative burden for the healthcare personnel.”

The ideal situation, according to Snoeijs, would be to expand on the current dialysis registry that already exists. “I would say that to expand a bit would be great; there’s recent progress in defining core outcome measures that can be easily measured without investing too much time and manpower, and there is a validation study—the VALID study, soon to be published—that also shows that it can be quite accurately measured by just the normal dialysis nurses who work in the everyday clinic.” This study, which was conducted by the Standardised Outcomes in Nephrology Group (SONG), defined the core outcome measure as “the time until the next intervention, or the number of interventions per year,” which, if recorded as part of a vascular access registry, “would take little effort and would be a good step forward,” according to Snoeijs.

tion” in the long term. “There are so many nurses, and we can create one or two new ‘fistula maven’, but in the end, we need hundreds of thousands of nurses in the dialysis units that are better educated.”

The first step to address this is, as Hentschel proposed, is “[VASA] will participate in the next ANNA conference; we actually have a session that they have graciously allowed us to talk about bringing VASA surgical and interventionist expertise and have a forum. In addition, we’ve proposed forming a joint working committee that develops standards and guidelines. In the UK for instance, they have this gold, silver, bronze cannulation proficiency,” which is exactly the type of certification that Hentschel, along with VASA, is hoping to introduce. “We’ll hopefully get there; we’re not there yet, but that would be the goal.”

Another aim of introducing more education and training, according to Hentschel, is creating more ‘careers’ from roles that are currently ‘jobs’. “If you become a dialysis tech, not technician,” he stated, “that’s a job, it’s not a career. But if you have certain levels of expertise that you can document, all of

a sudden it’s kind of a mini career. It also gives the opportunity to get education, to certify education, to say: Okay, I have this, I know this, and I know about this.

So there’s self-esteem on their side.” Not only are there improved career prospects for allied health members, but from the patient’s experience, which is what VASA is trying to improve, this accreditation provides quality assurance.

“The biggest thing,” Hentschel concluded, “is there was a recent KHI [Kidney Health Initiative] video which featured patients talking about their dialysis accesses. The number one thing that patients [highlighted] was the pain they experienced with failed needle insertions. So that’s where we—as physician leaders—may have an opportunity to help,” Hentschel suggested. He continued, saying that “you don’t want to come in and take over, that doesn’t work well, but we should act as [a partner], because there are certain things that we can provide to nurses [and technicians] and then they can take [this guidance] and they can educate others.”

“VASA is working on organised collaboration with allied health members—nurses, technologists, and physician assistants— that are in the dialysis units to carry the concepts that we’re all working on at the moment into the units.”

Dirk Hentschel

It is the “administrative burden,” however, that he feels is the greatest roadblock to further progress, at least in The Netherlands. “Privacy issues,” he says, “are, at least in The Netherlands, being taken care of, because all the patients already give consent to register their data in the renal replacement registry.” One thing that Snoeijs feels might be helpful with the administrative burden is if electronic patient files were able to capture the information and deliver it automatically to the registry. The issue with this however, may be that “[digital patient file services] are being overwhelmed by different requests like this, from each and every specialist.”

Snoeijs also outlined what he felt would be the main benefits of an updated and expanded vascular access registry, for both patients and clinicians. “I’d say that we would be able to better define the quality of care and the outcomes of care, and be aware when a unit is functioning below or above expectations so we can learn from the ones who do well and the ones who do not so well and try to improve their outcomes by

changing some aspects of their practice”.

Snoeijs’s presentation at the Hamburg Dialysis Access symposium concluded by exploring quality indicators, which align with what has been suggested in the Kidney Disease Outcomes Quality Initiative (KDOQI) guidelines. He stated he feels that “this aligns with this core outcome measure of the number of interventions. So, when we do register this, how many interventions, what kind of interventions are being done for the vascular access, I think that nicely aligns with the quality indicators that have been proposed and I think this would be helpful as a way forward.”

When asked what he felt was the key message for people to take from his presentation, Snoeijs said that by registering “core outcome measure for vascular access and haemodialysis—the access-related intervention rate, we can compare this measure to a benchmark and see which areas remain for improvement, which would be a great step forward to improve care for these patients”.

Home Dialysis

9

Hamburg Dialysis Access Symposium Point of View

a loop. The bandage wrapped around the fistula site penetrates the inner eye of the loop to fix the loop, not the line. An accidental strong pull at the line forces the loop to reduce its diameter, leading to a kink that is noticed by the dialysis device pressure unit. The needle itself, however, remains on the spot” Kopperschmidt said. “It’s crucial to think about what happens overnight when the needle is disconnected. This bandage technique is safe and easy to apply and prevents patients from being injured by massive blood losses.”

Kopperschmidt also called for awareness amongst patients on home haemodialysis of albumin loss or protein loss from long dialysis treatments. “When you understand that the protein sieving coefficients of dialyser membranes significantly decline within the first 20 minutes of a treatment, the difference in protein loss comparing long-term dialysis sessions with standard becomes negligible,” he said.

Turning to his zeal for kitesurfing, he displayed a gravity-defying image of himself kitesurfing to suggest this might be scary—to be at the mercy of strong winds and high waves, riding the tide on a tiny boat. “Some might see this as a time for the last prayer, but gaining the third dimension is not a nightmare,” he clarified, despite then going on to describe a situation when inevitable malfunctioning of kit can cause blood loss to soar, which definitely qualifies as much worse than a bad dream.

A Duni connector from the dialysis machine with an undetectable tiny overnight leak, for isntance, once caused severe blood loss. “After

Blood on the dialysis floor: An unforgettable night from 25 years on home haemodialysis It’s possible to expand the action radius of a passion for kitesurfing, despite being on long-term dialysis. Pascal Kopperschmidt (Hamburg, Germany) gave attendees at the 5th Hamburg Dialysis Access symposium (8–9 September 2023; Hamburg, Germany) a glimpse of the risks and promises of self-care from a patient’s perspective.

IN A TALK TITLED “TRUE CRIMES: AN unforgettable night”, Kopperschmidt, a physicist in the medical device industry, and a patient with 35 years of dialysis experience—of which the last 25 have been on home haemodialysis— delivered a flavour of his “nightmare scenarios” framed by stories and anecdotes of a life lived to the full while needing to be on dialysis.

Kopperschmidt has been a long advocate of self-care and has published several articles on the topic. “Self-care, whether in the home environment or a limited-care dialysis centre, empowers patients by allowing them more treatment autonomy. The choice of home rather than in-centre haemodialysis may be driven by, among other reasons, a demand for technically intensive care in a less formal environment,” he writes with co-authors. His mantra has often rested on the idea that “increasing individualisation of treatment at home often accompanies patients growing in self-confidence and experience of managing their own care.”

Returning to the question of nightmares, he treaded lightly on the lows. “Putting a haemodialysis machine into a camper van might well represent a nightmare to some,” he said, explaining that he saw dialysing at different locations as a way to extend the action radius of his passion for kitesurfing—this made the dialysis machine in the camper van, a reason to celebrate. “When you have something to celebrate, you must celebrate,” he urged.

Kopperschmidt displayed images of a dialysis machine in a tent in the Australian outback, revealing that this was shared with a friend for a couple of weeks in a national park (a nightmare for their wives, but not for us, he said). He then

pictured a “temporary dialysis unit in a barn in the north island of New Zealand equipped with two dialysis units (a nightmare for the cows and roosters running around the barn and wondering what was going on there, which was two guys having dialysis, he qualified), as well as the tiniest dialysis centre in the world: a Volkswagen bus, equipped with a dialysis machine, a narrow bed and space left for kitesurfing paraphernalia.

There are, of course, also clear risks associated with dialysing in both conventional and unconventional locations, and Kopperschmidt outlined these as well. “Self-punctures are a nightmare for many, many patients, but when you use the right technique, e.g. the buttonhole technique with the right needles, and yes, the right mindset, it’s absolutely not a nightmare to put that needle into that tiny hole, every other day. I’m on eight-hour nocturnal dialysis every other day, otherwise I probably wouldn’t be here,” he said, making the point that nocturnal haemodialysis, both in-centre and at home, allows for the delivery of more intensive haemodialysis, greater freedoms and better quality of life.

But these eight hours can be an ordeal, he cautioned, especially when the venous needle gets repositioned, or removed overnight unnoticed. “The venous dislodgement of the needle [is a case in point], but I have found a technical solution to that by using a bandage. Here the blood tube attached to the needle is guided into

Above: Enforced kinking to avoid venous dislodgement of the needle is a creative and technical solution that uses a bandage to secure a looped blood tube attached to the needle in order to alert the pressure unit of the dialysis machine

Seize the day: Pascal Kopperschmidt (right in the image opposite) and a friend celebrate being in the outdoors and being able to dialyse in different, sometimes unconventional locations

roughly seven hours, I woke up and couldn’t really move or say much. When trying to calculate the amount of blood lying on the floor, I guess it was about two litres,” Kopperschmidt added. “At the end of the day, I was transferred to an emergency unit for substitutional volumes and it took me six months to get to previous iron and haemoglobin levels.

“I recovered, as you can see; this was many, many years ago. You can imagine what that blood on the floor looked like; it was a night to remember.”

Course director of the Hamburg Dialysis Access symposium Robert Shahverdyan (Hamburg, Germany) told Renal Interventions: “Pascal has been a home haemodialysis patient for many years, with a truly impressive backstory. He is a good friend and has been one of the speakers at our symposium, every year since I started it back in 2008. When I was planning the case session called “My worst nightmare— cowboy up!” last year, it was only logical to invite Pascal to give us an exciting story from his long home haemodialysis experience, which he did incredibly.”

Issue 10 – February 2024

10

Profile

Q&A

Vandana Dua Niyyar From beginning a career in medicine to collecting Agatha Christie’s works, professor of medicine at Emory University (Atlanta, USA) Vandana Dua Niyyar speaks to Renal Interventions about her career in interventional nephrology (IN), how she occupies her time between her various roles and cases, and those that have inspired, advised and guided her throughout her career. As president of the American Society of Diagnostic and Interventional Nephrology (ASDIN), she also shares her thoughts on the future of IN and the biggest challenges facing dialysis care.

What drew you to a career in medicine and IN? I guess you could say that it runs in the family. I was very young when I knew that I wanted to be a doctor. My parents are my lifelong role models and inspiration—my father is a doctor and my mom is a teacher. I have been extremely fortunate to be able to nurture their legacy by incorporating both their passions into my career in academic medicine as a clinician-educator.

As for IN, it was destiny. I was considering a career as a physician scientist, and as part of my extended research fellowship, I was in the process of applying for funding and writing multiple grants including a National Institutes of Health (NIH) Mentored Patient-Oriented Research Career Development Award programme (K23). In the penultimate month of my fellowship, my division chief asked me to spend a month at our access centre and to evaluate its merits as a rotation for second year fellows. I had no idea that in fact they were the ones who were evaluating me—for a faculty position as an interventional nephrologist! It turned out to be a win-win for both sides—from the very first day itself, I realised I loved it—the instant gratification of getting the flow and thrill back after a successful thrombectomy was exhilarating, and a welcome addition to the delayed gratification that you get after many years in research.

Looking back, I feel very lucky that I have had the opportunity to be able to incorporate all these different experiences into my career.

Has your role as the president of ASDIN led to any developments in IN that you are particularly proud of?

February 2024 – Issue 10

It has been my absolute honour to serve ASDIN as president for the last two years. We have an incredibly engaged membership and leadership whose passion and dedication to help us achieve our mission of optimising dialysis access care is inspiring. Together, we have forged a strategic plan and restructured our committees to not only bolster long-term foundational support, but also to provide sustainable future impact and success.

A few of the initiatives that are particularly close to my heart include the establishment of a patient perspectives committee that seeks to bring—for the first time in over 20 years— the patient voice to ASDIN, ensuring that the patient perspective serves as our true north.

Our research committee has revamped our research grants and, in the pursuit and support of new knowledge, has initiated a mentoring programme.

As a passionate proponent of ultrasound, I am extremely proud of our comprehensive ultrasound certification programmes in three separate areas—renal ultrasound, dialysis access, and volume assessment—that were unveiled earlier this year and aim to bring the “D” (diagnostic) back in ASDIN. Our haemodialysis, vascular access, endovascular arteriovenous fistula (endo AVF) and peritoneal dialysis catheter (PD) certification processes have consistently maintained the delicate balance of establishing and enforcing stringent quality criteria that are essential to achieving and maintaining the high quality of care that our patients deserve.

ASDIN recognises how critical it is for all of us to work together across disciplines and as a

global community, and share our knowledge and expertise with each other. We have expanded our outreach to multidisciplinary professionals including surgeons and frontline dialysis staff, as well as internationally through a multitude of educational offerings including ASDIN Global and our ASDIN-international society of nephrology (ISN) ultrasound webinars, while exploring further collaborations worldwide.

The field of dialysis access is rapidly evolving and ASDIN is uniquely positioned to harness this momentum through innovation and advancement. As president, it has truly been my privilege to be a part of this exciting journey and explore and expand upon the vast and diverse opportunities for collaborations in research, training and education.

What is the biggest question in IN that you would like to see answered?

Dialysis access is meant to be the patient’s lifeline, but more often than not, it tends to be their most vulnerable area—their Achilles’ Heel. For years, we have been describing the desired characteristics of what constitutes the “ideal” access but despite recent advances, have not yet been successful in achieving the lofty goal of an access that is durable and functional with minimal interventions and complications. I would like us as a community to take on this challenge, really listen to the patient and incorporate their perspective into future innovations, to design the next generation of dialysis access.

What do you think the next 10 years will look like for kidney care?

This is an exciting time to be a nephrologist.

After many years of stagnation, the landscape in the management of kidney disease is rapidly changing, and for the better. For years, we had only renin-angiotensin system (RAS) inhibition as definitive targeted therapy to slow kidney disease progression but with the emergence of powerful new medications like sodium-glucose co-transporter-2 (SGLT2) inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists, we now have an unparalleled opportunity to change the trajectory of kidney disease. The optimists among us hope they will ultimately keep many of our patients from requiring renal replacement therapies. For those individuals suffering from kidney disease, in the future I foresee patient-centred personalised care that incorporates scientific and technological innovations to be the norm rather than the exception.

What, in your view, is the biggest roadblock to further developments in dialysis?

The kidney was the first solid organ whose function could at least be partially replaced by a machine, as well as the first to be successfully transplanted. It is fascinating to see how dialysis has evolved over the years. From the first machine developed by Dr. Willem Kolff using a wooden drum and cellophane casing, to the ubiquitous dialysis machines we see nowadays, clinical trials of the wearable artificial kidney in progress, and implantable bioartificial kidneys and cellular regeneration that are in preclinical stages, we have come a long way—but there is still a lot more to accomplish.

Dialysis as a way of replacing kidney function remains sub-optimal, as it focuses on solute and fluid clearance, but does not address the metabolic or endocrine functions of the kidney.

Innovators are working across the board and

Fact file Current appointments: Professor of Medicine, Division of Nephrology Emory University, Atlanta, USA Consultant Nephrologist, Grady Memorial Hospital and Emory University Hospital, Atlanta, USA President, American Society of Diagnostic and Interventional Nephrology (ASDIN)

Education: 1989–1994: Medical School: Pt BDS PostGraduate Institute of Medical Sciences, Maharishi Dayanand University, Rohtak, Haryana, India. Dean: Dr S B Siwach, MD 1994–1995: Internship: Pt BDS Post-Graduate Institute of Medical Sciences, Maharishi Dayanand University, Rohtak, Haryana, India, Dean: Dr S B Siwach, MD

Honours (selected): 2019: Distinguished Service Award, American Society of Diagnostic and Interventional Nephrology 2019: Woodruff Leadership Academy 2019: Nanette Wenger Distinguished Service Award Emory DOM 2020: Distinguished Clinical Service Award, American Society of Nephrology (ASN) 2021: Eminent Physician, Emory School of Medicine (SOM) 2021: Clinical Excellence Award, American Nephrologists of Indian Origin 2022: Outstanding Quality Achievement Award, Emory Department of Medicine

Illustration by: Andy Watt / NB Illustration

Profile

combining forces to overcome the limitations of tissue engineering, miniaturisation, nanotechnology, and cellular regeneration in order to create a next-generation technology that would use a patient’s own cells to create a fully functional implantable organ. It is a work in progress and to quote Vincent Van Gogh: “As practice makes perfect, I cannot but make progress; each drawing one makes, each study one paints, is a step forward.” With time, I am confident that these roadblocks will be overcome and growth in this area will be exponential.

What is the best advice that you give your students who express an interest in pursuing IN as a specialty?

IN is a natural extension of our role as nephrologists and I encourage my students to be excellent nephrologists first, and then build on that foundation to develop expertise in the hands-on component of IN. I remind them to think beyond just the procedural component of IN and to remember that an interventional nephrologist is one who is a) committed to dialysis access, b) under-

stands the complexities of the dialysis patient and the process of dialysis, and c) has expertise in the procedures required, as Gerald A Beathard (University of Texas Medical Branch, Galveston, USA) said. Interventional nephrologists, with their unique skillset, have a pivotal role to play in optimising care of the patient on dialysis, breaking down silos and work in tandem with the other professionals. They are uniquely positioned to be the best advocates for their patients, and the leaders of the multidisciplinary team taking care of this vulnerable patient population. Of course, compassion and intellectual curiosity are also a must for everyone in medicine.

What is your philosophy within medicine, particularly within IN? I have always felt that medicine is not just a career, it is a calling. I live by the phrase “choose a job you love and you will never have to work a day in your life”. Medicine is truly my life’s passion and joy, and when I am with my patients, to be honest, it does not even feel like it is ‘work’.

As for the procedural component of IN, I will

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quote one of my mentor’s wise words: “The enemy of good is better.” It is not only essential to know when and how to perform a procedure, but even more important to know when to stop.

What are your interests outside of medicine?

Outside of medicine, I love spending time with my family, travelling all over the world, and exploring new places, cultures, and cuisines.

While the kids were growing up, I focused only on my family and my work, but now that we are empty nesters, I have been able to rekindle some of my other interests.

I love reading—mostly fiction—I am a huge Agatha Christie fan and have a hard bound copy of every single title she has written! My current non-fiction favourites are Becoming by Michelle Obama and Born a Crime by Trevor Noah. I am a Bollywood aficionado, and I have recently started taking Bollywood dance classes. I spend a lot of time outdoors when I can, and love to capture the beauty of our world through my camera lens; I now have a very nice collection of nature photography.

Issue 10 – February 2024

12

Obituary

Ground-breaking transplant surgeon Professor Sir Roy Calne dies, aged 93

tion, particularly in its early days. Perhaps most notable was the development of effective immunosuppression to prevent transplant rejection, a field he continued to advance throughout his career. For so many patients he changed their lives, and he always maintained a keen interest in their achievements”.

As well as achieving many surgical firsts, Calne was also a champion for the use of immunosuppression, becoming the first to use an immunosuppressant to prevent the body from rejecting a transplanted organ. He was also the first to introduce the immunosuppressant drug cyclosporine into routine clinical care for transplant recipients.

Calne was married to Patricia Whelan in 1956 and had six children. His son, Russel, spoke to the BBC, saying that their father was “an incredible person” to be raised by. He also added that “he was an amazing character, a slight eccentric and a wonderful father to six children. We were all very, very proud of him for everything he has achieved and done, and we’ve been to some amazing places due to his accolades”.

His family said Calne died in Cambridge late on Saturday 6 January 2024.

Professor Sir Roy Calne, the surgeon who led a team that performed the first liver transplant in Europe, has died at the age of 93.

THE OPERATION THAT HE PIONEERED took place on 2 May 1968 at Addenbrooke’s Hospital in Cambridge, UK, following the first successful transplant of the same organ in the USA a year earlier.

Whilst Calne was known for his ground-breaking work with liver transplants, he was also at the forefront of developing techniques used for kidney transplantation. Calne pursued a career in the field of transplantation whilst studying medicine at Guy’s Hospital in London, where he was told that there was nothing that could be done for a man that was dying of kidney failure.

In 1960, Calne showed that the survival of a transplanted kidney in a dog could be extended by the use of 6-mercaptopurine (6-MP), results which he published later that year in The Lancet. As well as this, Calne also performed the first successful combined stomach, intestine, pancreas, liver and kidney cluster transplantation in 1994.

Calne was also a fellow of the Royal Society and was professor of surgery at Cambridge University between 1965 and 1998, where he introduced their kidney transplant programme. It is also notable that, whilst he did retire as chair of surgery at the University of Cambridge in 1998, he still continued to perform kidney transplants well into his seventies.

In 2020, Calne was reunited with Angela

Dunn, a former patient of his that was a recipient of a kidney transplant in 1970, who was believed to be the longest-surviving transplant patient in the world. Speaking at the event, Dunn said that “before my operation I did not expect to make 30. I cannot express enough my gratitude to my donor’s family, to Professor Sir Roy Calne, all the medical staff who have watched over me and to my husband Eric”. Also in attendance at this reunion was John Bradley (Addenbrooke’s Hospital, Cambridge, UK), who worked with Calne for many years. When asked about Calne’s achievements, Bradley stated that “he overcame many barriers to kidney transplanta-

Professor Sir Roy Calne

University of Edinburgh researchers aim to create ‘wearable kidney’ A team at the University of Edinburgh’s School of Engineering, led by Maria Grazia De Angelis (University of Edinburgh, Edinburgh, UK), are working on creating a wearable haemodialysis machine with the use of an alternative ‘smart’ filtration system.

THE TEAM RECEIVED FUNDING FROM KIDNEY Research UK to find a replacement for the current filtration process, which requires many litres of ultrapure water. The hope is that, with a new system that allows for water to be filtered and recycled, the amount of water needed can be reduced, allowing for a miniaturised, wearable haemodialysis device to be created.

De Angelis et al plan to use machine learning to work through the thousands of filter material combinations to find the one that works best for the purification process prior to testing the filter membrane in a laboratory setting.

“Machine learning accelerates work which would traditionally take years into just a matter of months,” said De Angelis. “By feeding the computer programme as much information as possible about the characteristics of the materials and the toxins that it will need to filter, we can get a quite accurate understanding of whether the chosen substance would perform well in a clinical setting. Then, testing in a lab will be used to confirm the information from the artificial intelligence programme by using fluids February 2024 – Issue 10

“He overcame many barriers to kidney transplantation, particularly in its early days. Perhaps most notable was the development of effective immunosuppression to prevent transplant rejection, a field he continued to advance throughout his career.”

John Bradley

from real patients, ensuring that we can be certain that the material will be effective when introduced in a clinical trial setting.”

Whilst a new filtration system could allow for patients to be less restricted in their daily lives, there is also the possibility that this new device could reduce some of the side-effects that can come from haemodialysis, such as sickness and fatigue, by reducing the time between treatments.

The issue, said De Angelis, is: “Dialysis is designed to replicate the blood-filtering function of the kidneys, but a

key difference is that a healthy kidney is working all the time while haemodialysis patients only receive treatment three times a week. By the time of their next scheduled treatment not only is their body full of toxins but their blood pressure is very high. Four hours is not long enough to be on dialysis in terms of cleaning the blood, but it is impossible for patients to have haemodialysis 24 hours a day. Having a device that is portable would allow more frequent dialysis over longer periods of time; this could drastically reduce the side-effects of the treatment. It could also enable patients to have a degree of control over their own treatment, administering it at a time that suits them.”

The team’s hope is that it can have a shortlist of materials that are the best fit for the filtration system within the next couple of years, after which it will test the most effective materials for use in a portable dialysis device.

The new ‘wearable kidney’ device is hoped to be an alternative for current dialysis treatments (pictured above)

“Testing in a lab will be used to confirm the information from the artificial intelligence programme by using fluids from real patients, ensuring that we can be certain that the material will be effective when introduced in a clinical trial setting.”

Paris Vascular Insights

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A full protocol and multidisciplinary team are needed for endoAVF to be fully effective At the most recent Paris Vascular Insights (PVI) meeting (8–10 November 2023, Paris, France), Renal Interventions spoke to Gianmarco Falcone (Azienda Ospedaliero Universitaria Careggi, Florence, Italy) about endovascular arteriovenous fistulas (endoAVF) and what he feels is needed to ensure that this relatively “new concept” of vascular access creation is used to its full potential.

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ne of the first things that Falcone highlighted was that it is essential to have a strong multidisciplinary team (MDT) at the core of any endoAVF programme, and to ensure that all members of this team are fully trained so that the MDT can succeed with the use of endoAVF technology. He stated that “to succeed in this kind of technology, we have to have a working multidisciplinary team [and a] very dedicated programme”.

To achieve this, he suggested that centres should set up a “kind of dialysis training programme” that employs a “hub and spoke technique” to ensure that large centres are equipped to undertake endoAVF procedures. He also added that it is essential to outline the roles of individual team members—such as dialysis nurses—in the protocol, so that all key roles have responsibilities that are clearly outlined.

Expanding further on what he felt was essential to a good endoAVF programme, Falcone added that two key aspects of a functioning team is “an MDT working together”, but also that “part of the MDT should be the nephrologist that is the team leader, [along with] the interventional radiologist, vascular surgeon, maybe anaesthesiologist” but crucially, “the dialysis nurse”. “At our centre it is the dialysis nurse,” he outlined, “who is

in charge of the daily use of the fistula and who has the responsibility of conducting the first-line scanning of the patient, which then allows them to highlight to the MDT any kind of problem—whether the fistula is open or not, whether they see thrombosis or maybe a suspicious stenosis—so that they can assess and approach any issues in the best way possible for that patient.”

Another point that he highlighted is the role that patient selection plays in a successful endoAVF programme. “[For patient selection] currently the need is to have the most individualised approach possible that may vary from patient to patient. The standard ‘distalfirst’ approach cannot be pursued in all patients. Whenever it is deemed appropriate, the algorithm we are following is the same. So, if we can use a distal radiocephalic [fistula], we go for a distal radiocephalic. If the patient is not judged eligible for distal fistula creation or in case of a previous failure of the distal fistula,” Falcone stated, “maybe then we can consider using endoAVF.” EndoAVF, he avers, is kind of a mix, because it’s not a proper distal, but it’s also not a proximal fistula. “They’re something created in the deep-venous system and they are mainly slow-flow fistulas, so they can also protect the patient for cardiac impairment. So yes, the patient selection plays a key role in

More education is needed for peritoneal dialysis to be utilised fully At the most recent Paris Vascular Insights (PVI) meeting (8–10 November 2023, Paris, France), Renal Interventions spoke to Maurizio Gallieni (professor of nephrology, Department of Biomedical and Clinical Sciences, Università degli Studi di Milano, Milan, Italy) about peritoneal dialysis (PD) and what he feels is needed to fully utilise this technique, and what he sees as the obstacles that are currently preventing that from happening.

Is peritoneal dialysis underutilised?

This was exactly the topic of my presentation here at the PVI meeting, and the answer is yes, it is underutilised. I presented data that summarises the prevalence of different kinds of renal replacement therapies in Europe, and in some countries, you have more transplants, in some countries you have more haemodialysis, but in all countries, you have a very small number of patients who are treated with PD. And therefore definitely, despite wide variations in practice, a common feature is that, in almost all of the European countries, there is very little PD.

Gianmarco Falcone

an endoAVF programme, but basically we are quite used to the patient selection for every procedure.”

Responding to a question about “stumbling blocks” when placing endoAVF and whether secondary interventions fell into this category, he stated that “from the patient perspective, secondary interventions could be understandably seen

“It is essential to outline the roles of individual team members, such as dialysis nurses, in the protocol, so that all the key roles have clear responsibilities outlined.”

Could you summarise why peritoneal dialysis is underutilised?

It is surprising somehow that this technique is underutilised, because it has several important advantages [to other techniques]. It is a home-based therapy, so it gives more freedom to the patient, for example, for travel. If a patient has a house somewhere else, they can spend three or six months there, while doing that with haemodialysis is more difficult. Also, outcomes are very good. Therefore, finding the reasons why there is underutilisation is kind of difficult, but there are several. One is misconceptions about the disease; some nephrologists, who are the ones that should give the opportunity to patients for

Maurizio Gallieni

as a very adverse aspect; but we have to explain to the patient that these kinds of fistulas, as with the others, will possibly have to have some small adjustment before working effectively”.

When asked about the data, Falcone stated that “we can see that surgical AVF have two to three reinterventions per patient per year, and the data we have so far for endoAVF showed us that we are talking about less than one per patient per year. So, I’m not really worried about secondary interventions”.

As the interview concluded, Falcone summarised his feelings on the need for a dedicated programme for endoAVF. He stated: “I think that a tailored, dedicated programme is mandatory to succeed in this new technology for patient benefits,” adding that “we really need a co-working mindset for the MDT, and—as it’s a new technology—we really need some homogeneous data in literature to validate the technique.”

this kind of modality, do not trust the technique. There is also a problem of organisation, training of staff, and it is very worrying that in many countries around the world, including the USA, some nephrology fellowship programmes do not have the manpower for teaching PD. So, it is really a very multifaceted issue. Economic implications are also important, as, despite being a technique that costs less, in some cases, there is no incentivisation.

Doctors are more prone to use haemodialysis for financial reasons.

In your view, what factors could lead to good growth and an uptake in peritoneal dialysis use, if they were to be addressed?

I think the most important one is education. If we start rebuilding education for nephrologists and fellows (and also surgeons and radiologists who are performing vascular access procedures) on the importance of PD and the easier approach to renal replacement therapy that it provides, then it should translate to better outcomes for patients. Also, implementing new approaches to PD and differentiating the nephrology care on offer—for example, by providing assisted PD to patients who are unable to perform self-treatment and who don’t have a family caregiver able to perform PD treatment—might increase the number of patients treated with this technique.

Do you have any final points that you want to emphasise?

I believe that peritoneal dialysis has a great potential for growth, improving patient outcomes and reducing the cost of dialysis.

Issue 10 – February 2024

14

Multidisciplinary Participation

VASBI

VASBI team reflects on recent meeting and what matters to vascular access as a discipline Reflecting on this year’s meeting, what makes them unique and what changes have occurred since the last meeting, the leadership of the Vascular Access Society of Britain and Ireland (VASBI) feel that the keys to the continued growth of vascular access are patient involvement, engaging physicians early, and remembering the importance of multidisciplinary participation.

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hilst speaking to Renal Interventions at their latest annual meeting in Birmingham, UK (28–29 September 2023), VASBI vice president Jeremy Crane (Imperial College Healthcare NHS Trust, London, UK) outlines the growth that they have experienced, saying that “the number of delegates have surpassed any previous meeting since inception of VASBI, not just from one specialty but across multidisciplinary teams involved in vascular access; haemodialysis and vascular nurses, interventional radiologists, nephrologists, and transplant and vascular access surgeons.” He continues by highlighting that this growth and diversity in specialties is “also reflected in the presentations”, saying they “have been top quality across the board, so everyone has interest in the range of presentations.”

It is this multidisciplinary focus that both Crane and VASBI president Robert Jones (Queen Elizabeth Hospital, Birmingham, UK) feel is essential not only to the society and the meeting, but also to vascular access in a broader sense.

Speaking to Renal Interventions separately, Jones states that “there is a lot of enthusiasm and passion for vascular access around the country, and VASBI is the umbrella for that, in the sense that it brings everyone together, because we are the only true multidisciplinary vascular access society in the UK.” When asked how he felt the multidisciplinary aspect of vascular access has been represented globally, Crane adds that “I go to a lot of meetings internationally and I enjoy them all, but of all the ones that I have been to, I do believe that this is the most multidisciplinary based on all the vascular access meetings. I think that that is one of the big attractions of VASBI [and] that is reflected in the number of delegates we have [attending] today.”

Patients guiding clinicians Something that both Jones and Crane show a strong passion for is the involvement of patients in VASBI and society meetings in general. “What patients add is so important but is often overlooked,” Crane expresses. He continues, saying “we think we might be doing the right thing, but if a patient says to you ‘actually, that is not what we want’, you are going down the wrong road without realising it. A patient can level things out and explain to you exactly what is important

February 2024 – Issue 10

to them.” This is the key point, he feels, for all clinicians, “because what is important to them should be important to us.”

For Crane, it is not just about showing compassion for the patient that is receiving treatment; it is also beneficial for the discipline on a larger scale. “Actually learning from the patients is a way of advancing vascular access, so it is not just about the technical or scientific side, it is the personal side, the patient side. And of course, it is not about treating the disease, it is about treating the patient with the disease, and that is something that we really need to home in on, and that is something that VASBI is trying to implement as a society.”

Similarly, Jones feels that patient involvement is key to the continued growth of VASBI, and apparent. “We have a patient on council; he is vocal and proactive during the meetings and in general [and] he shares his experiences, some of which, as doctors, we often overlook from the psychology perspective. That brings us on to the fact that we have had a psychologist input at the meeting this year as well, which is really important.” It is not only within the council of VASBI that patient participation is vital, Jones postulates. “As you witnessed at the meeting this year, we also invited some other patients as delegates, who were very proactive in discussions, guiding us as clinicians on how we could be better treating patients.”

What lies ahead With regards to the future of VASBI and subsequent meetings, there is a clear priority at the forefront of both Crane and Jones’s minds; new blood. With concerns coming out of the meeting regarding the quality of training in all relevant vascular access specialties, the president and vice president of the society are keen to attract trainees and those who are earlier in their Robert Jones (left) and Jeremy Crane

VASBI 2023

160

The most registrants in the history of the society

career, as “they are the future”, as Jones puts it.

He adds that “a few people around the room over the last couple of days have said to me that ‘we did not even know that this meeting or society existed, and the content and quality have been fantastic’. So, I think we have a way to go in terms of promoting and publicising the society.” His plan to address this lack of awareness?

“Obviously, social media is the main vehicle for this sort of thing nowadays, so I think we can use this a bit more effectively moving forward.”

One factor, according to Crane, that may be contributing to the lack of awareness is the fact that vascular access is “somewhat a Cinderella specialty”, as he puts it. Despite this, however, he is still confident that they will be able to attract new physicians to it. “It is the kind of specialty that, once you get into it, it evokes a passion. A lot of that is because, when it comes to dialysis, those patients are the underdog. In other words, […] transplants are a very “sexy” sort of field; it is always in the news, it is timely, it is topical, and the underdog is the dialysis patient, who has either never had a transplant or can never have a transplant.” He feels that working in vascular access allows you to “really champion their cause” and that “once you get that bug, it catches, and then you get that real passion for it.”

Final thoughts As our conversation draws to a close, the vice president of VASBI reflects on the progress that has been made since taking the reins alongside Jones. “When Rob Jones and I took over as president and vice president respectively, we really wanted to grow this meeting and we wanted to make it purely a multidisciplinary team (MDT) meeting, rather than having one aspect of the MDT overrepresented. I feel that we brought in lots of new people at this meeting, and new people begets more new people. I think there were lots of people that have never been to VASBI before and I am hoping that the success of this meeting will be reflected in the upcoming meeting, when we are hoping that even more people come. I think that, as the organisation grows, as we get more revenue from industry, for example, we can invite people from across the globe to come and speak to us, so that the meeting just gets better and better in terms of quality and the amount of delegates attending. We are going to be in Cardiff in 2024, a similar time of year, a great venue and we are really excited.”

As Jones closes: “As you can see, the meeting has grown since 2022; we had record attendance in 2023 [with] 160 registrants, which is the maximum we have ever had in the history of the society. So, it is a good signal that people are enthusiastic about these meetings, and it is the best forum for us to learn and obtain experience from one another.”

Surgical Training

15

VASBI

Better training for vascular access surgery needed, according to trainees

New training course aims to meet urgent need in interventional nephrology A new PGCert training course for Interventional Nephrology (IN) has become available at Newcastle University and, according to Saeed Ahmed (South Tyneside Sunderland Foundation Trust, Sunderland, UK), this course will meet an urgent need for more training in the field of IN. SPEAKING TO RENAL INTERVENTIONS AT the 2023 Vascular Access Society of Britain and Ireland (VASBI) meeting, Ahmed outlines the key aspects of this course that he feels make it uniquely positioned to continue the growth of IN in the UK. “This is the first in the UK, probably in the world for learning IN from a certificated university course. What they will learn differs, as it is modular based, so the current modules are renal biopsy, peritoneal dialysis catheter management, haemodialysis access management [and] point -of-care ultrasound.”

He continues, explaining that “what we are offering is a degree level course; all the others [internationSaeed Ahmed ally] are mainly one-off courses that you go to. Some are certificated; American Society of Diagnostic and Interventional Nephrology (ASDIN) is certificated, Association of Vascular Access and inTerventionAl Renal Physicians (AVATAR) is certificated, but they are not university accredited. We are offering you an accredited course, which is the first in the world, and that fits nicely with the International Society of Nephrology’s view of having IN centres around the world.”

The importance of a training course such as this was highlighted by the presentation of an abstract addressing the availability of training for IN, which also took place at the VASBI meeting. Khalid Rashid ( James Cook University Hospital, Middlesbrough, UK) et al collected data from 41 participants, from 11 regions of the UK, in a hands-on IN workshop about their competencies in 10 different nephrology procedures, with participants being awarded a score of one for each procedure they said they were competent in and a cumulative score out of 10 being calculated at the end of the questionnaire.

The results of this questionnaire showed that, with a total possible score of 10, the mean score of all participants was 2 ±1.39. Whilst 29 participants were competent in performing native and transplanted kidney biopsies, only one participant was trained to perform vein mapping, and no participant was trained in performing advanced procedures such as arteriovenous fistula/arteriovenous graft thrombectomy, central vein angioplasty, and fistuloplasty.

Rashid et al concludes that there is a clear need for more frequent IN training courses that can prepare nephrologists to perform complex interventions. He emphasises how crucial these courses are, saying that more need to be organised so that “nephrologists [can] contribute effectively to the multidisciplinary team (MDT) to manage complex renal patients.”

In a presentation taking place at the latest Vascular Access Society of Britain and Ireland (VASBI) meeting, Thomas Richards (University Hospital Sussex, Brighton, UK) gave a presentation outlining an abstract which states that over half of UK senior vascular surgery trainees surveyed believe that they are not able to undertake independent primary access surgery.

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ichards outlined how he and co-author Karim El Sakka (University Hospital Sussex) collected these data; with the use of SurveyMonkey, a short questionnaire was circulated via Health Education England (HEE) deaneries and the UK vascular surgery trainees’ society (the Rouleuax Club), and was used to survey all senior (ST6–ST8) vascular surgery trainees in the HEE vascular surgery training programmes. In this survey, the trainees were asked to report a range of data, including their training grade, training deanery, experience of access surgery, and whether they felt able to independently undertake primary access surgery post-completion of training (post certificate of completion of training).

Of the 28 senior vascular surgery trainees that responded to the survey, 30% were at ST6 level, 33.3% ST7 and 37% ST8. The responses that these trainees provided showed that 29% had been involved in <10 cases, 36% in 10–25 cases, and 36% had been involved in >25 cases. The final result that was highlighted was the fact that 54% of senior vascular surgeon trainees felt that, even once they had completed their training,

they would be unable to undertake independent primary access surgery.

“The problem is increasing demand [on vascular surgeons]. The solution is more organised and more formalised training.” Richards’ closing statement sums up the presentation and evidence that he provided; the lack of training for vascular access surgery is causing it to fall by the wayside in vascular surgery, which will only lead to continuously increasing demand on the surgeons that are trained in the relevant procedures. Richards feels that more training, such as the access surgery fellowship in Brighton (the only one accredited by the Vascular Society), are needed for this growing issue to be resolved.

“Of the 28 senior vascular surgery trainees that responded to the survey, 30% were at ST6 level, 33.3% ST7 and 37% ST8.

The responses that these trainees provided showed that 29% had been involved in <10 cases, 36% in 10–25 cases, and 36% had been involved in >25 cases.”

“This is the first in the UK, probably in the world, for learning interventional nephrology from a certificated university course.”

Issue 10 – February 2024

16

Advertorial

This advertorial is sponsored by Medtronic

Hypertension guidelines “change the thinking” on renal denervation Hypertension is a leading cause of heart attack, stroke and death, impacting more than 1.2 billion adults worldwide. For decades, the frontline treatment for this condition has been a varying combination of pharmacotherapy and lifestyle modifications, but a device-based treatment—renal denervation—has emerged as a potential option where current treatment options may not be enough. Crucially, as more evidence about the safety and efficacy of renal denervation emerges from clinical trials, new guidance in Europe and recent device approvals in the USA raise the prospect that more patients could receive this treatment.

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otably, the new and updated 2023 European Soci- worldwide with the Symplicity system, which recently ety of Hypertension (ESH) guidelines recommend gained US Food and Drug Administration (FDA) approval the use of renal denervation among patients with for the treatment of hypertension. apparent resistant hypertension as “additive or alterTo date the clinical programme has completed two native to increasing medication”, as well as in patients randomised, sham-controlled trials, one involving the with uncontrolled hypertension who are non-adherent use of renal denervation in the presence of antihyperor intolerant to antihypertensive drugs. Patients may be tensive medications—the SPYRAL HTN-ON MED study— on fewer than three drugs at the time of their selection and another investigating the procedure in the absence for the therapy. of medications—the SPYRAL HTN-OFF MED Pivotal trial.

“This is the first guideline that has changed the view These have yielded important insights, with SPYRAL on renal denervation,” says cardiologist Felix Mahfoud HTN-ON MED demonstrating durable reductions in (Saarland University Hospital, Homburg, Germany), ambulatory systolic blood pressure (SBP) of -18.7mmHg highlighting the significance of this development. For at three years in patients receiving the renal denervaKonstantinos Tsioufis (University of Athens, Athens, tion procedure. In SPYRAL HTN-OFF MED, a reduction Greece), a past president of ESH, this upgrade to the of office systolic blood pressure of -9.2mmHg was seen guidelines cements renal denervation as the “third pillar” at three months. Both trials have also demonstrated for the treatment of hypertension. “It is not an alterna- the robust safety profile of the device. Further trials are tive therapy to drugs, it is not a competitive strategy, it ongoing, including SPYRAL AFFIRM, which seeks to is something synergistic—an additional treatment,” he validate the long-term safety, efficacy and durability of states. “This is the first time we have recommendations, the Symplicity procedure. and this publication will change the way of thinking.

The clinical programme also includes the Global Now physicians will have one more tool in their hands SYMPLICITY Registry, which is the largest individto reduce high blood pressure.” ual source of information available in the “We have plenty of hypertensive drugs, renal denervation space, providing realand we also know that lifestyle modification word data from more than 3,400 patients is able to lower blood pressure,” Mahfoud enrolled to date. Mahfoud presented threetells Renal Interventions. “But, many year insights from the registry at EuroPCR patients do not adhere to it, and in many 2023 (16–19 May, Paris France), where he instances it is a lifelong therapy.” reported sustained and clinically meaningTsioufis similarly describes hypertenful blood pressure reductions of -16.7mmHg sion as the “most important contributor to in office SBP in patients with uncontrolled cardiovascular mortality and morbidity” Felix Mahfoud hypertension independent of the antihyand highlights that there are a significant pertensive medication regimen. proportion of hypertensive adults whose These studies are among the most blood pressure remains uncontrolled. recent clinical data to “There are many reasons for having low have contributed to the levels of controlled hypertension,” Tsiouupgraded class of recomfis explains. “Among them, poor medicamendation for renal denertion adherence is a major factor, so we need vation in the new and expanded 2023 something to contribute to the blood presESH guidelines for the management of artesure-lowering effect, irrespective of medirial hypertension. The latest guidelines, to cation adherence.” which Tsioufis and Mahfoud both contribKonstantinos Tsioufis Mahfoud and Tsioufis have been among uted, are intended to reflect expanded the leading investigators in studies assessing renal dener- hypertension patient populations, as well as innovations vation, which has been shown to be capable of lowering in therapeutic strategies developed to treat uncontrolled blood pressure as a complementary option to the exist- hypertension—which includes renal denervation. ing treatments. The technique uses energy targeted to Careful patient selection sits at the heart of the guidethe renal nerves to modulate the sympathetic signalling lines, which set a clear benchmark as to when renal denerbetween the kidneys and brain to reduce blood pres- vation can be considered. Patients who have uncontrolled sure. “We know that the sympathetic nervous system is blood pressure despite the use of antihypertensive drug involved in the development, progression and mainte- combination therapy may be candidates for the procedure, nance of hypertension and various other cardiovascular or in instances where drug treatment elicits serious side diseases,” explains Mahfoud as to why this area is the effects and poor quality of life when estimated glomerular target of the treatment. filtration rate (eGFR) is >40 ml/min/1.73m2, the guidelines Much of the contemporary knowledge of the safety state. Patients with resistant hypertension, if eGFR is >40 and efficacy of renal denervation comes from clinical ml/min/1.73m2, may also be candidates for the therapy. study programmes including the SPYRAL HTN Global Both of these scenarios carry a Class II recommendation.

Clinical Programme, that has investigated the use of Importantly, the guidelines state that selection the Symplicity Spyral™ (Medtronic) system, and is the of patients should be done as part of a shared decilargest so far, having studied >4,000 patients including sion-making process, noting that “understanding the real-world data from the Global SYMPLICITY Registry. patients’ perspective, exploring their preference and Additionally, over 25,000 patients have been treated expectation, is crucial” prior to any procedure.

February 2024 – Issue 10

“We know from patient preference studies that roughly 30% of patients are interested in an intervention to lower their blood pressure, and this is something you should discuss with them,” says Mahfoud. “You can inform the patient about the potential risks and benefits of the procedure, and then, in a shared decision-making process, come to a decision over whether or not you pursue renal denervation or stay with conservative approaches to lower blood pressure.”

“Nowadays, we have to have patients at the centre of our decision,” adds Tsioufis. “Spend time with the patient to explain the risk associated with uncontrolled hypertension, the potential risk of an invasive procedure, even a minimally invasive procedure such as renal denervation, and the potential benefits. After this discussion, if the patient continues to prefer renal denervation, you should offer them this possibility.”

Furthermore, the guidelines state that the procedure should be carried out in experienced centres to guarantee appropriate selection of eligible patients, as well as the completeness of the procedure.

When it comes to device selection, operators can utilise systems that use different technologies to achieve renal denervation. The energy source used in the Medtronic system is radiofrequency energy and both Tsioufis and Mahfoud recognise that the benefits of radiofrequency renal denervation are supported by the largest amount of data coming from clinical trials.

“The radiofrequency technique is the most studied.

It is the technique that introduced the concept of renal denervation, and up to now more than 4,000 patients have been included in the Spyral programme in the setting of clinical trials,” Tsioufis comments to Renal Interventions. “It is the technology that has been used more extensively for research purposes. Now we have data to show that it is safe and effective.”

With these new guidelines in hand, physicians can now make this therapy available to their patients who may need an additional therapeutic option to control their blood pressure.

“This is the first time we have recommendations, and this publication will change the way of thinking. Now physicians will have one more tool in their hands to reduce high blood pressure.”

Symplicity Spyral™

Latest News

Clinical and Industry News

Example of HistoSonics technology targeting kidney tissue to be destroyed in a non-invasive histotripsy procedure

First patient treated with HistoSonics Edison histotripsy system

HistoSonics, developer of a non-invasive platform and sonic beam therapy called histotripsy, has announced the treatment of the first patient in its pivotal #HOPE4KIDNEY trial.

The US Food and Drug Administration (FDA) approved the investigational device study in early 2023 and it is designed to evaluate the safety and efficacy of the company’s Edison system to destroy targeted kidney tumours non-invasively and without the need for needles or incisions. The #HOPE4KIDNEY trial is a multicentre, open-label, single-arm trial, planned to enrol up to 68 patients.

The procedure was performed by urologist Michael McDonald (AdventHealth Celebration, Kissimmee, USA), a leader in advanced urologic procedures, including robotics. “At the start of my surgical career in the 1990s, open surgical techniques were the primary method of medical operations.

However, this quickly changed with the introduction of laparoscopic surgery in the late 1990s and robotic surgery in the early 2000s,” said McDonald.

“I’m excited about the potential of emerging technologies such as histotripsy to improve patient safety and outcomes.” The procedure was conducted under the auspices of the AdventHealth Research Institute, where physicians and researchers are currently conducting more than 650 studies and clinical trials.

In 2020, there were an estimated 628,355 people living with kidney and renal pelvis tumours in the USA, and an additional 81,000 people to be diagnosed with kidney tumours in 2023.

Current kidney therapies such as partial nephrectomy and thermal ablation are invasive and exhibit complications from bleeding and infection that non-invasive histotripsy may avoid. While surgical intervention is the “gold standard” in removing kidney tumours, a noninvasive approach with histotripsy provides the potential to destroy targeted tumours without damaging non-targeted kidney tissue. Additionally, histotripsy’s purely mechanical mechanism of cellular destruction could preserve function of the kidney’s urine collecting system.

“We are extremely excited to have McDonald and his team at AdventHealth Celebration treat the first patient as part of the #HOPE4KIDNEY trial,” said

HistoSonics president and CEO, Mike Blue. “Our goal is to enable physicians to precisely target and destroy kidney tumours with our novel, non-invasive solution, avoiding the morbidity and complications seen with current invasive surgery or ablative techniques,” added Blue. The company expects to take advantage of key learnings from its initial Phase I kidney study, called the CAIN trial, and technical enhancements with its Edison platform during the #HOPE4KIDNEY study.

SanReno Therapeutics announces acquisition by Novartis, underscoring China’s substantial renal market potential

SanReno Therapeutics has announced that it has been acquired by Novartis, becoming an indirect, wholly-owned subsidiary of Novartis. The investors that helped found SanReno—including Pivotal bioVenture Partners China, Frazier Life Sciences, Samsara BioCapital, and Versant Ventures— have sold their equity securities in the company.

SanReno, which was established as a joint venture between Chinook Therapeutics (also now a subsidiary of Novartis) and the investor consortium, holds exclusive rights in Greater China and Singapore for two late-stage assets targeting Immunoglobulin A Nephropathy (IgAN): atrasentan and zigakibart. SanRena is currently undertaking Phase 3 development of atrasentan, an oral endothelin A receptor antagonist (ERA), for IgAN. It demonstrated clinically meaningful and highly statistically significant proteinuria reduction at the 36-weeks interim analysis, successfully meeting the primary endpoint of its Phase 3 study. It has also been awarded approval by the Chinese Centre for Drug Evaluation (CDE) for zigakibart (BION1301), a subcutaneously administered monoclonal antibody targeting APRIL (A Proliferation Inducing Ligand), for entry into the Phase 3 study in October 2023.

This acquisition is unique, as it is a rare instance of a Chinese biotech company being acquired by a multinational pharmaceutical company, a fact which is compounded by the transaction being completed within the first two years of SanReno’s formation.

The transaction helps to highlight China’s potential within the global renal market, and also aligns with Novartis’ commitment to championing novel therapies for kidney diseases.

Summa Therapeutics receives US FDA approval for injectable angioplasty balloon catheter

Summa Therapeutics, a specialty angioplasty balloon medical device company, announced that its innovative line of injectable angioplasty balloon catheters has been cleared for marketing by the US Food and Drug Administration (FDA) for the treatment of peripheral artery disease.

Summa’s new Finesse injectable angioplasty balloon catheters are

cleared by the FDA for percutaneous transluminal angioplasty (PTA) treatment of peripheral artery disease including iliac, femoral, popliteal, infra-popliteal, renal arteries and arteriovenous (AV) dialysis access.

The Finesse injectable angioplasty balloon catheter differs from conventional angioplasty balloon catheters because it provides a port for the injection of radiopaque contrast material or other fluids in addition to performance of balloon angioplasty.

“We are delighted to receive FDA clearance for our Finesse angioplasty balloon product line,” said Timothy Murphy, Summa’s chief executive officer. “This achievement underscores our commitment to delivering innovative, minimally invasive vascular solutions that address critical unmet needs in the field of interventional medicine. We believe that the Finesse product line has the potential to revolutionise angioplasty procedures, providing physicians with an advanced toolset to treat patients with critical limb-threatening ischaemia [CLTI].”

The new angioplasty balloon catheter was designed to facilitate increasingly complex below-the-knee angioplasty

procedures for patients with CLTI, a risk factor for leg amputation. The Finesse injectable angioplasty balloon catheter is the first of its kind, designed to treat small arteries in the calf. The combination of a diagnostic catheter and angioplasty balloon catheter in one device is expected to reduce catheter exchanges, lower contrast doses, and shorten procedure times, and lead to better patient outcomes and lower costs. Summa launched the product line in the fourth quarter of 2023 in the USA.

Laminate Medical announces first implantation of VasQ AVF device Laminate Medical has announced the first implantation of its VasQ device in the USA, performed by Ari Kramer (Spartanburg Regional Hospital, Spartanburg, USA). The VasQ technology was granted US Food and Drug Administration (FDA) approval in September 2023, and is reported to be the only approved product on the market currently, designed to assist surgical fistula success from the point of creation.

VasQ is a nitinol-based external support device for the artery and vein anastomosis during the surgical creation of an arteriovenous fistula to promote maturation into a functional access for haemodialysis. The device was designed to provide structural reinforcement of the mobilised vessels and guides a more stable arterial flow profile as it transitions into the vein.

The importance of this innovation has been underscored by the surge in use of central venous catheters (CVC) during the COVID-19 pandemic, the press release details, leading to heightened

17

risk of infection and mortality. Creating more functional fistulas, it is hoped that VasQ may help to reduce CVC use in this patient population.

In a statement, Laminate CEO, Tammy Gilon remarked: “This accomplishment represents the culmination of 12 years of dedicated effort, and we are elated to introduce VasQ to the population of the USA.”

Twelve-month first-inhuman data from Xeltis’ aXess haemodialysis vascular conduit trial presented at VEITHsymposium 2023

Xeltis has announced “highly encouraging” 12-month results from its first-in-human (FIH) aXess vascular conduit trial. The data were presented

by Frans Moll (University Medical Center Utrecht, Utrecht, The Netherlands) at the 2023 VEITHsymposium (14–18 November, New York, USA).

At 12 months, 100% secondary patency, 78% primary assisted patency and 0% infections were observed in data from 20 patients implanted with the aXess conduit. According to Xeltis, these results represent a significant improvement over current standard of care. This performance builds on the six-month data presented in April 2023 at the Vascular Access Society Congress in Porto, Portugal. To date, more than 3,500 dialysis sessions have been conducted across the six centres in Belgium, Italy, Latvia and Lithuania.

AXess is a restorative conduit which enables the creation of a new, longterm living vessel for haemodialysis vascular access. The aXess FIH trial is a single-arm feasibility study in Europe evaluating the preliminary safety and performance of the aXess graft in patients older than 18 years with end-stage renal disease and deemed unsuitable for fistula creation. Followup visits were conducted at regular intervals after the initial procedure, with study follow-up visits to be conducted for five years. A separate pivotal trial of aXess is underway, enrolling up to 110 patients across up to 25 sites in nine EU countries, with over 40 patients already implanted.

The full data were presented by Moll in a presentation entitled ‘Novel application of polymer technology to create endogenous tissue with host collagen and endothelium compatible with flowing blood: One-year clinical results of the aXess graft’.

Eliane Schutte, CEO of Xeltis commented: “The outstanding 12-month data from our FIH study highlights aXess’ potential to transform the field of vascular access as a whole by stopping the cycle of interventions and infections.”

Frans Moll

Issue Issue10 10––February January 2024

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Latest News

Clinical and Industry News Diality unveils new haemodialysis system at ASN Kidney Week 2023

Blood potassium monitor under development to benefit patients with chronic renal failure CardioRenal and CHU Grenoble Alpes have announced an innovation that allows chronically ill patients to measure their blood potassium levels autonomously and accurately.

The Tenor device enables patients to measure their blood potassium levels at home, similar to how diabetic patients have conducted blood sugar self-tests for many years.

“Tenor will represent a considerable improvement in treating patients living with chronic renal failure. Thanks to Tenor, patients will be able to take potassium measurements much more frequently at home,” said Pierre-Louis Carron (CHU Grenoble Alpes, Grenoble, France), principal investigator in the Gamma clinical trial. “In this way, doctors will have the means to influence treatment and better regulate potassium levels, one of the vital parameters for cardiac function.”

Currently under clinical development, Tenor is designed for home use by patients with renal or cardiac insufficiency. Tenor performs a precise potassium measurement and transmits the values to the CardioRenal web platform, to which attending physicians have access. This enables them to make informed decisions on therapeutic adjustments.

The Tenor device is the result of a multi-year research collaboration between CardioRenal and the French Alternative Energies and Atomic Energy Commission (CEA) in Grenoble. In 2023, Tenor received the breakthrough designation device label from the US Food and Drug Administration (FDA).

“In current practice, blood potassium measurement is invasive and requires venipuncture, which prevents it from being carried out as often as necessary.

In certain phases of treatment for chronic patients, potassium values need to be available frequently to optimise treatment. With Tenor, the patient will be able to take this measurement as often as necessary,” said Patrick Rossignol, co-founder of CardioRenal.

For patients with the most advanced stages of kidney disease, the risk of adverse cardiovascular events is strongly linked to potassium variations outside normal ranges. Patients measuring their potassium levels should help limit this risk. Specifically, dialysis patients can easily check their levels on Sunday when the risk of hyperkalaemia is highest. The company stated that clinical studies will be carried out over the coming years to demonstrate the benefits of the Tenor device.

February2024 January 2024––Issue Issue10 10

Diality introduced its Moda-flx haemodialysis system on 4 November 2023 at the American Society of Nephrology (ASN) Kidney Week meeting, where it was also the subject of a poster session titled ‘Blood flowrate accuracy with Diality haemodialysis systems’.

Diality’s goal for the Moda-flx haemodialysis system is to reduce the burden of care for all kidney care stakeholders and progress Diality’s mission of improving lives impacted by kidney disease.

The main draw of Diality’s Modaflx haemodialysis system, according to authors Clayton Poppe, Nicholas Hyun and Blaine Murakami (Diality), is accurate system performance, one aspect of which is accurate blood flow measurement. The Moda-flx haemodialysis system is able to correct factors that can lead to a reduction in the expected flowrate compared to the manufacturers stated accuracy at high blood flowrates. These factors, which can lead to a reduction in flowrates of up to 80–100ml/min at a setpoint of 500ml/min (compared to the accuracy of +/-10% stated by most haemodialysis manufacturers), can also cause a reduction in Kt/V of 8.4%, depending on the dialysis flowrate.

According to Poppe et al, the use of an algorithm that collects information from a range of variables—including pump head speed, inlet and outlet pressures, tubing ageing and temperature—can predict the flowrate by comparing these factors to changes in blood flow.

The authors conclude that “understanding the variables that lead to changes in blood flow and using them to control blood flow in real time can lead to better blood flow accuracy” which in turn, they add, “can lead to higher average Kt/V for higher treatments with high blood flowrates.

Scott Drake

Scott Drake appointed as Cordis CEO

Cordis has announced that its board of directors has appointed Scott Drake as chief executive officer (CEO), effective immediately. Drake most recently held the position of executive chairman of the Cordis board of directors. He will succeed Shar Matin, who has stepped down as CEO. “Scott Drake has been on the Cordis board of directors since we acquired Cordis in 2021,” said Hunter Philbrick, H&F partner and Cordis board member.

“He has a long history building world-

class medical device organisations, bringing to market groundbreaking patient saving innovations and driving commercial excellence—along with the reputation of attracting, retaining, and developing world-class talent. Scott believes in Cordis’ ability to transform the medical industry, and with him as CEO, Cordis will achieve its vision of pioneering breakthrough cardiovascular technologies.”

Drake has over 30 years of medical device experience including as the president and CEO of the Spectranetics Corporation, where he increased shareholder value from approximately US$170 million to US$2.2 billion during his six-year tenure.

“I want to thank Shar for all he has done to stand Cordis up as an independent company. I have been on the Cordis board of directors for over two years, and I am thrilled to be taking on a more active role as CEO,” states Drake. “We are entering the next phase of the business, where Cordis is launching new products and driving a revolutionary business model with Cordis-X that will benefit our team, customers, patients, and shareholders.”

Recor Medical gains first US FDA renal denervation approval

Recor Medical has become the first company in the USA to have a device-based therapy approved for the treatment of hypertension, after it was announced that the US Food and Drug Administration (FDA) had approved the company’s Paradise ultrasound renal denervation (RDN) system.

The Paradise system is intended as an adjunctive treatment option when lifestyle changes and medications have not adequately controlled a patient’s blood pressure. The Paradise catheter features the HydroCooling system, which circulates sterile water through the balloon catheter during the procedure to help protect the renal artery wall.

Approval of the Paradise system follows Recor’s positive FDA Advisory Committee Panel in August 2023. In 2023, results from Recor’s US pivotal study, the RADIANCE II randomised clinical trial, were published in the Journal of the American Medical Association (JAMA). In the study, the Paradise system met both the primary safety and effectiveness endpoints without any major adverse events.

“Despite the longstanding availability of dozens of affordable anti-hypertensive medications, blood pressure control rates in the USA are alarmingly low and falling.

Given the significant blood pressure reductions seen in the ultrasound renal denervation trials, the Paradise ultrasound renal denervation system offers a much-needed advancement in our currently available options to control hypertension,” said site principal investigator Naomi Fisher (Brigham and Women’s Hospital, Boston, USA).

“Ultrasound renal denervation has proven efficacy in patients with truly resistant hypertension, a population for whom medication therapy often fails.

It is also effective in patients with mild to moderate hypertension who cannot tolerate enough medication to control their blood pressure.”

The Paradise system previously received CE mark and has been

successfully introduced in Europe and is an investigational device in Japan.

“Recor is leading the way in bringing an innovative solution to clinicians and their patients struggling to control blood pressure. This FDA approval is the culmination of years of technical research and rigorous clinical studies,” said Lara Barghout, president and chief executive officer (CEO) of Recor Medical. “We are grateful to the patients who participated in the studies and to the clinical trial investigator teams whose diligence and dedication made FDA approval possible. We look forward to making this technology available to physicians and their patients nationwide.”

“Approval of the Paradise ultrasound renal denervation system marks an important milestone for the company and provides a new adjunctive treatment option for hypertension which remains inadequately controlled despite conventional therapies,” said Noriko Tojo, president and representative director of Otsuka Medical Devices and executive director of Otsuka Holdings, the parent company of Recor Medical.

“We are excited for patients and their healthcare professionals to have access to this technology to assist in managing hypertension and improving outcomes.”

Invizius appoints nephrologist Bernard Canaud to its clinical advisory board

Invizius, a biotechnology company developing treatments for patients on dialysis, announced the appointment of Bernard Canaud to its clinical advisory board.

Canaud brings with him over 40 years of experience as an authority in the field of kidney disease and dialysis, with more than 350 peer-reviewed articles on the subject. In 2009, he was the recipient of the highest French order of merit, the Legion d’Honneur, for his medical achievements. Alongside this new appointment with Invizius, Canaud is currently emeritus professor of Nephrology at the Montpellier University School of Medicine in France.

When asked to comment, Professor Canaud said: “Invizius’ unique product H-Guard has the potential to reduce the therapeutic burden and save patients’ lives by addressing the inappropriate activation of the complement system.

In spite of significant advances in the field of biocompatibility, studies have demonstrated that the persistent activation of the complement system by extracorporeal blood purification or nanomedicine therapy remains potentially harmful in the long and short term for patients exposed to these therapies. By targeting factor H and inhibiting both the alternate complement activation pathway and its amplification loop with H-Guard, we have the ability and potential to make a tremendous difference to patients while mitigating associated risks.”

Bernard Canaud

Conference Calendar

Conference Calendar

23–25 February

American Society of Diagnostic and Interventional Nephrology (ASDIN) 20th Annual Scientific Meeting New Orleans, USA asdin.org

06–08 March

British Transplantation Society (BTS) Annual Congress 2024 Harrogate, UK bts.org.uk/events-meetings

23–28 March

Society of Interventional Radiology (SIR) Meeting 2024 Salt Lake City, USA sirmeeting.org

11–13 April

14–18 May

23–25 April

23–26 May

International Multidisciplinary Endovascular Forum (IM Endo forum) Florence, Italy imendoforum.com/ Charing Cross (CX) Symposium 2024 London, UK cxsymposium.com

29–30 April

Euro Nephrology Summit 2024 Paris, France nephrologycongress.conferenceseries.com/ europe

19

National Kidney Foundation (NKF) Spring Clinical Meetings 2024 Long Beach, USA kidney.org/spring-clinical 61st European Renal Association (ERA) Congress Stockholm, Sweden era-online.org/events/stockholm-2024

28–31 May

Leipzig Interventional Course (LINC) 2024 Leipzig, Germany leipzig-interventional-course.com/visitors/ linc-2024

Meet our editorial board Nicholas Inston

Ziv Haskal

Stephen Hohmann

Robert Jones

Chairman of the Editorial Board

Board Member

Board Member

Board Member

Nicholas Inston is a transplant and vascular access surgeon, and the clinical service lead for renal surgery, at Queen Elizabeth Hospital in Birmingham, UK.

Ziv Haskal is a professor of radiology, and an interventional radiologist and interventional oncologist, at the University of Virginia School of Medicine in Charlottesville, USA.

Stephen Hohmann is a vascular and general surgeon at the Texas Vascular Associates clinic in Dallas, USA.

Robert Jones is an interventional radiologist at Queen Elizabeth Hospital in Birmingham, UK.

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Issue 10 – February 2024

Celebrates th

ANNUAL SCIENTIFIC MEETING

A Special Edition

February 23-25, 2024 | Sheraton New Orleans

SCHEDULE AT A GLANCE

Program Chairs: Dalia Dawoud, MD, MSc, FASDIN & Saravanan Bala, MD, FASN, FASDIN

FRIDAY, FEBRUARY 23, 2024 POINT OF CARE ULTRASOUND PRECOURSE HANDS-ON PRECOURSE FELLOWS EDUCATION WORKSHOP SATURDAY, FEBRUARY 24, 2024 UNRESOLVED OLD BUSINESS NEW APPROACHES AND PERSPECTIVES CLASH OF THE TITANS HOME DIALYSIS - UNCOVERING THE POTENTIAL FOR HOME SWEET HOME ENDOAVF MASTERY: ARE WE OLD AND WISE ENOUGH? REVOLUTIONIZING DIALYSIS ACCESS & KIDNEY CARE WITH CUTTING EDGE INTERVENTIONS RESEARCH AND ABSTRACTS CASE DISCUSSIONS SUNDAY, FEBRUARY 25, 2024 DAY OUT IN HOLLYWOOD - RATED R “LET’S MAKE ENDS MEET” BUSINESS OF VASCULAR ACCESS CARE: PRESENT & FUTURE CUT, SUTURE, AND ACTION IN ASDINVILLE PROOF IS IN THE PUDDING EVIDENCE-BASED MEDICINE & KDOQI

ASDIN.ORG | ASDIN.ORG/20THANNUAL | 601-924-2220 | INFO@ASDIN.ORG