PHILADELPHIA – A covered nitinol stent graft effectively restored and maintained patency of hemodialysis access routes that had been impaired by in-stent restenosis.
The combination of a stent graft plus angioplasty was significantly more effective than angioplasty alone at keeping the access routes open, Dr. Alexander Yevzlin reported at Kidney Week 2014.
Maintaining healthy vascular access is key for effective dialysis; this is usually accomplished by bare metal stenting. However, in-stent restenosis is so common that patients may need angioplasty every 3-6 months to maintain access patency.
In comparison, coronary angioplasty is usually sustained for at least 5 years, said Dr. Yevzlin, director of interventional nephrology at the University of Wisconsin, Madison. “This places a very large extra burden of morbidity on patients, and a large burden of cost on society.”
The ongoing RESCUE study is examining the Fluency Plus cardiovascular stent graft for in-stent restenosis. Fluency is a nitinol stent covered with a plastic graft of expanded polytetrafluoroethylene. Dr. Yevzlin reported preliminary 6-month data.
The study has randomized 265 patients with in-stent restenosis of a dialysis access circuit to treatment with either balloon angioplasty alone, or angioplasty plus the stent graft. The primary endpoints are access circuit primary patency at 6 months and 30-day safety. Safety endpoints are any additional interventions including surgery, hospitalization, or prolongation of an existing hospitalization; or death. The secondary endpoint is postintervention lesion patency (defined as the interval after the index intervention until the next reintervention at the original treatment site or until the extremity is abandoned for permanent access).
There were no safety issues, Dr. Yevzlin said; by 30 days, 97% of patients in both groups were still free of any adverse event.
By 6 months, access circuit patency was significantly higher among those who received stent grafts than those who had angioplasties alone. Postintervention lesion patency was 65% in the stent graft group and 10% in the angioplasty group – a significant difference.
The stent graft performed well in both arteriovenous grafts and fistulas. In a subgroup of those with an arteriovenous graft, the postinterventional lesion patency rate was 58% in the stent graft group and 5% in the angioplasty group. In the fistula subgroup, the rates were 72% and 15%, respectively.
The meeting was sponsored by the American Society of Nephrology. Dr. Yevzlin disclosed financial relationships with Bard Peripheral Vascular, the manufacturer of the stent graft; Phraxis; CytoPherx; and Covidien.