Drug-Coated Balloons Better for Reopening Dialysis AV Fistulas

Arteriovenous (AV) fistula stenosis remained patent for dialysis more often when treated with a drug-coated balloon versus standard models, the IN.PACT AV Access trial showed.

The IN.PACT AV drug-coated balloon increased target-lesion primary patency at 6 months to 82.2% compared with 59.5% treated with non-drug-coated balloon angioplasty (P<0.001).

Serious adverse events involving the arteriovenous access circuit within 30 days were similar between devices (4.2% vs 4.4%, P=0.002 for noninferiority), Robert Lookstein, MD, MHCDL, of the Icahn School of Medicine at Mount Sinai in New York City, and colleagues reported in the New England Journal of Medicine.

“These findings are encouraging, as vascular access dysfunction, including the need for multiple interventions to maintain patency, is a major source of morbidity in our dialysis patients,” Vandana Dua Niyyar, MD, of Emory University in Atlanta, and president-elect of the American Society of Diagnostic and Interventional Nephrology, told MedPage Today.

Lookstein and colleagues noted that repeat endovascular therapy for dialysis circuit stenoses has only been used in about half of cases, with placement of a central venous catheter often used instead.

“Clinical outcomes of this type of dialysis are poor; the use of a central venous catheter is associated with a higher risk of death from cardiovascular or infectious causes and of death from any cause than the use of an arteriovenous fistula for dialysis,” they wrote. “Therefore, any treatment method that has the potential to offer patients with end-stage renal disease uninterrupted hemodialysis can dramatically affect patients over the course of their lives.”

The IN.PACT AV device was approved for use in AV dialysis fistulae based on the IN.PACT AV Access trial in November 2019.

This approval came amid an upheaval in paclitaxel-coated balloon (and stent) use for peripheral indications, following a late 2018 meta-analysis showing late mortality risk in that setting.

IN.PACT AV showed no significant mortality signal in the 12 months after the procedure (9.4% vs 9.6% with a standard balloon), Lookstein’s group noted.

Still, longer-term risk is concerning and “needs to be investigated further, not just in PAD, but also in dialysis access,” Niyyar said, noting that IN.PACT AV’s protocol states that the trial participants will be followed for 5 years after the index procedure. Meanwhile, clinicians need to “be really thoughtful where and how we use them,” she suggested.

“Moreover, it would be interesting to see the impact on circuit patency and safety of different doses of paclitaxel as well as other antiproliferative agents, including sirolimus,” Niyyar added.

The trial included 330 participants with new or restenotic lesions in native upper-extremity arteriovenous fistulas who were randomized after successful high-pressure percutaneous transluminal angioplasty to get treatment with a drug-coated balloon or a standard balloon.

Clinically-driven target-lesion revascularization occurred significantly less with the drug-coated–balloon group, at 16.4% versus 38.5% among controls. Access-circuit thromboses were similar between the treatment groups (2.0% vs 3.4%, respectively).

The drug-coated balloon also significantly reduced repeat interventions to maintain target-lesion primary patency and to maintain access-circuit primary patency through 6 months along with increasing proportion with primary patency of the entire dialysis circuit from arterial inflow to venous outflow, inclusive of the target lesion, at that point.

One limitation was the single-blind design, necessary because the two balloon types look different, which could have biased repeat intervention rates.

“Between-group differences in the number of inflations and the maximum inflation pressures could be considered confounders,” the investigators added. Also, “further studies will be required to evaluate the safety and effectiveness of drug-coated balloons for the treatment of central vein obstruction, in-stent restenosis, or arteriovenous graft stenosis.”