Endo AV Access: New Data Emerge on the WavelinQ System

(Leipzig, Germany) January 28, 2020 -- Tuesday afternoon saw a first-time data release from the prospective, multicenter study to evaluate the WavelinQ endoAVF system (BD), used to create an endovascular arteriovenous fistula (endoAVF) for patients requiring vascular access for hemodialysis.¹

This real-world, multicenter, prospective study represents the largest WavelinQ analysis to date, including the rigor of an independent ultrasound core lab and clinical events committee.

WavelinQ is a dual-catheter system that uses radiofrequency (RF) energy to create an autologous fistula. Two catheters are aligned in the desired artery and its adjacent deep vein in the proximal forearm with the use of rare earth magnets. The venous catheter has a discrete electrode which corresponds to a ceramic backstop in the arterial catheter and employs a sub-second burst of RF energy for the creation of an endoAVF.²

Surgical fistula creation is recommended in the forearm first, as this does not preclude later attempts at upper arm fistula placement should the forearm placement fail. However, the rate of forearm failure is relatively high. EndoAVF presents a potentially viable first option in vascular access, because it does not interfere with the possibility of subsequent surgical radiocephalic or elbow fistula placement.²

With endoAVF, the site of fistula creation is typically in the proximal to mid forearm – potentially the radial, ulnar, or interosseous vessels. The blood flow from the endoAVF enters the deep venous system and cross-fills across deep and superficial systems of the forearm and arms via perforating and communicating venous branches.

A number of studies of the WavelinQ have explored its potential. Most recently, a single-center observational study by Inston et al (2020) compared three-year data of a cohort of patients receiving an endoAVF fistula (n=30) matched with a contemporary cohort receiving surgical radiocephalic arteriovenous fistulas (n=40). For primary outcome measures such as time to fistula formation, superior performance of the endoAVF was found, with a trend for improved primary patency at 6 and 12 months for the WavelinQ group.²

Other small-scale, retrospective studies, including Rajan et al (2015)³ and Yang et al (2017)⁴, support the notion that an endoAVF requires fewer interventions to maintain patency than surgical AVF at 12 months. In 2017, Lok et al published findings of the prospective, multicenter, single-arm Novel Endovascular Access Trial (NEAT), finding minimal complications association with the endoAVF approach and high 12-month cumulative patencies.⁵

WavelinQ’s three-year post-market study results were presented by Rob Jones, MD (Queen Elizabeth Hospital, Birmingham, UK). The study, which completed in September 2019, involved 100 participants with chronic kidney disease who underwent endoAVF placement using WavelinQ (both 4 French [F] and 6F systems were used). Patients underwent follow-up at 3, 6, and 12 months. Primary outcome measures included time to first intervention to maintain patency, or time of successful endoAVF creation until any intervention designed to maintain or re-establish patency or loss of endoAVF patency.¹

Describing the importance of devices that can permit percutaneous endovascular arteriovenous fistula (AVF) formation, Dr Jones said, “The importance to the patient is that it is minimally invasive to create and doesn’t involve an incision in the skin. 

“It is also cosmetically more acceptable than the conventional fistula, because it does not become aneurysmal. And, most importantly, the evidence to date suggests fewer interventions and therefore, fewer visits to the hospital are required to maintain functionality.”

Discussing the results of post-market study, he continued, “The new data demonstrate that in a real-world population, in multiple countries, in the hands of different operators and different disciplines, the WavelinQ fistula is highly successful both in terms of creating the fistula, but also in its functionality and cannulation. Ninety-five percent functional patency [was achieved] at six months.

“The true measure of endoAVF is the ability to cannulate and the patient to receive dialysis, which is demonstrated in this study. The implications [of this study are] that the results of the earlier trials are reproducible in the real world, including with the use of the new 4F device. We are able to create percutaneous fistulae that are useable for dialysis, offering patients more options.” 

The next-generation 4F device received the CE Mark in 2017. Commenting on how this lower-profile device expands upon the applicability of the 6F WavelinQ device, Dr Jones noted, “From the patient’s perspective, this has made the procedure a safer alternative. The access is of a narrower caliber, and therefore, hemostasis following the procedure is easier to achieve and less likely to cause bleeding complications.

“From the operator’s perspective, there is added confidence when it comes to hemostasis. It also opens up the options of fistula creation, because we can now use the wrist vessels for access to the target site, which we couldn’t with the 6F device. Also, from the operator’s perspective, there is no noticeable difference between the 4F and 6F WavelinQ in terms of successful fistula creation.”

Concluding with an outlook of upcoming studies of the WavelinQ device, Dr Jones noted that two new trials will continue its investigation, one based in the U.S. and a second trial that will include global enrollment.

References

1. everlinQ endoAVF Post Market Study. ClinicalTrials.gov. Available online at https://clinicaltrials.gov/ct2/show/NCT02682420. Accessed January 28, 2020.
2. Inston N, Khawaja A, Tullett K, et al. WavelinQ created arteriovenous fistulas versus surgical radiocephalic arteriovenous fistulas? A single-centre observational study. J Vasc Access. 2020:1129729819897168.
3. Rajan DK, Ebner A, Desai SB, et al. Percutaneous creation of an arteriovenous fistula for hemodialysis access. J Vasc Interv Radiol. 2015;26(4):484–90.
4. Yang S, Lok C, Arnold R, et al. Comparison of post-creation procedures and costs between surgical and an endovascular approach to arteriovenous fistula creation. J Vasc Access. 2017; 18(Suppl. 2): 8-14.
5. Lok CE, Rajan DK, Clement J, et al; NEAT Investigators. Endovascular proximal forearm arteriovenous fistula for hemodialysis access: results of the prospective, multicenter Novel Endovascular Access Trial (NEAT). Am J Kidney Dis. 2017; 70(4): 486-497.