Arteriovenous fistula (AVF) creation is challenged by high rates of primary failure resulting in prolonged central venous catheter usage and a necessity for multiple interventions to become usable for dialysis treatment. A vascular external support for (AVF) creation (VasQ, Laminate Medical, Tel Aviv) was designed to improve fistula success by addressing the mechanical and hemodynamic mechanisms of fistula failure in the juxta-anastomotic region. Multiple publications have consistently demonstrated improved 6-month outcomes with VasQ during AVF creation. Here, the largest prospective comparative study results are presented for VasQ over a 24 month study period.

A multi-center prospective study was conducted on 144 patients (90% brachiocephalic and 10% radiocephalic) at 15 sites implanted with VasQ in the United States. Additionally, a comparative group of 782 patients treated by the same study surgeons immediately prior to the VasQ trial enrollment period was developed from the Medicare claims database. Demographic, procedural and post-procedural data was collected for up to 24 months post-surgery. To emulate randomized studies and balance the patient characteristics between VasQ cohort and Medicare control cohort, propensity score weighting method was applied. Inverse probability treatment weighting using average treatment effect on the treated (IPTW-ATT) method was utilized to evaluate average treatment effect of the VasQ implant by weighting the control group up to the treated group. Statistical comparisons of primary patency (freedom from intervention), AVF usability (continuous use for dialysis over a minimum of 30 days), and post-creation intervention rates were made against the matched comparator group. Descriptive comparisons were made for primary failure rates (abandonment before first use by 6-month follow-up) as well as 24-month secondary patency (freedom from abandonment) rates against published meta-analysis results. Bootstrapping method with 2,000 iterations were preformed to obtain the 95% confidence intervals for comparison of each endpoint.

The VasQ patient cohort was 61% (88/144) male, 35% (51/144) black and 70% (101/144) had a prior vascular access with a median age of 60 and BMI of 30.4. The demographic data for both VasQ and Medicare control groups before and after weighting is shown in Table 1. The diameter range of the vessels as the creation site was 2.0 mm to 6.6 mm for arteries and 2.3 mm to 7.8 mm for veins. Rates of steal (2.5%), infection (0.7%), (pseudo)aneurysm (0.0%) and seroma (0.0%) compared favorably with standard fistula creation. The primary endpoint of superior 6-month primary patency for VasQ AVFs compared against the matched cohort was met with an odds ratio 3.27 [95%-CI: 2.15 - 5.17; p < .0001]. Secondary AVF usability endpoints were also superior for the VasQ AVFs with an odds ratio of 2.15 [95%-CI: 1.32-4.47; p = .0069] at 3 months and 2.05 [p = .0059] at 6 months. Additionally, VasQ AVFs reported a lower intervention rate of 0.97 per patient-year vs 1.91 per patient-year in the comparator group (p < .0001). Primary failure occurred in 7.9% of VasQ AVF patients, which compares favorably to contemporary meta-analyses reports ranging from 22.0% to 32.2%.1-3 The low primary failure rate correlated to a high successful 2-needle cannulation rate of 88.3% [95%-CI: 80.2% to 94.2%] for VasQ patients by the 12-month follow-up as shown in Figure 1. Finally, secondary patency rates at 24-month follow-up were superior to contemporary meta-analyses with VasQ AVF patients reporting 76.6% vs the reported range for 53.7% to 63.0% for standard AVFs.1,2

The results from the largest prospective comparative study on creating AVFs with a vascular external support demonstrate more dialysis patients receive patent fistulas that more quickly become usable for dialysis with fewer interventions and retain long-term durability over a 24-month period. Use of the VasQ device integrated into standard surgical practice should serve to improve overall AVF outcomes for the dialysis patient community.

Hajibandeh S, Burton H, Gleed P, Hajibandeh S, Wilmink T. Impact of arteriovenous fistulas versus arteriovenous grafts on vascular access performance in haemodialysis patients: A systematic review and meta-analysis. Vascular. 2021 Aug 31:17085381211041473. doi: 10.1177/17085381211041473. Epub ahead of print. PMID: 34461784. Al-Jaishi AA, Oliver MJ, Thomas SM, Lok CE, Zhang JC, Garg AX, Kosa SD, Quinn RR, Moist LM. Patency rates of the arteriovenous fistula for hemodialysis: a systematic review and meta-analysis. Am J Kidney Dis. 2014 Mar;63(3):464-78. doi: 10.1053/j.ajkd.2013.08.023. Epub 2013 Oct 30. PMID: 24183112.