The RENOVA (Post-approval study for the Flair endovascular stent graft) results showed that stent grafts keep access sites open significantly longer in haemodialysis patients than angioplasty alone, according to a presentation given at the Society of Interventional Radiology’s (SIR) Annual Meeting (13−18 April 2013, New Orleans, USA).
The data, which was named the SIR abstract of the year, was presented by Ziv J Haskal, University of Maryland School of Medicine, Baltimore, USA.
He spoke about the 12-month results of the RENOVA trial, a multicentre, randomised controlled clinical study of an endovascular stent graft vs. a percutaneous transluminal angioplasty. Two hundred and seventy dialysis patients treated for collapsed access sites at 28 US centres were randomised and 138 subjects underwent stent grafts while the remaining 132 had balloon angioplasty.
According to his study—“Stent graft vs. balloon angioplasty for failing dialysis-access grafts”— published in the New England Journal of Medicine, anatomic success with the stent graft compared to percutaneous transluminal angioplasty was 94% and 73% respectively. At six months, Haskal explained, binary restenosis was 27.63% for the stent graft and 77.61% for angioplasty.
He also noted that the 12-month reintervention rate to maintain patency was 1.9% for the stent graft and 2.4% for angioplasty. The 12-month index of patency function was 5.3% for the stent graft and 4.4% for angioplasty, for access circuit primary patency it was 24.1% and 10.3%, and for treatment area primary patency it was 4.7% and 24.8% respectively. The latter was statistically significant (p<0.001).
“Results of the study exceeded our expectations, and that is a boon for dialysis patients,” said Haskal. “Dialysis is very demanding, and anything that prevents access sites from failing and reduces the need for invasive treatments of surgery will dramatically improve patients’ quality of life—while reducing health care costs,” he added. Grafts have been considered short-term solutions previous to the RENOVA trial, with 75% requiring invasive interventions in under a year, said Haskal.
In his conclusion he said that the RENOVA interim results reflected real-world experience and assessments and that sustained and significant improvement in access circuit primary patency vs. percutaneous transluminal angioplasty was 2.3% greater at 12-months.
He added that there was no difference in infection rates or thrombosis. “The use of this ePTFE stent graft remains the only current technology that demonstrates a significant patency advantage over balloon angioplasty at six and now 12 months.”
“More than 100,000 angioplasties are performed a year due to this narrowing. What this stent method does is not only reopen the vein, but turn the graft into an inline flow, so that the blood enters the vein at a more natural angle,” he added.
“This controlled study proves that we can achieve durable long-term solutions for these patients, reducing their invasive procedures and thus improving their quality of life,” he added.
The Flair stent graft (Bard) is FDA approved.