ETAP Trial: Nitinol Stent Bests Angioplasty for Popliteal Artery Disease

MIAMI, FLA.—In treating blockages of the popliteal artery, a nitinol stent performs better than standard angioplasty alone with minimal clinical adverse events, according to a multicenter study. Stented patients also had improved walking ability at 1-year postprocedure compared with those who underwent angioplasty.

For the Endovascular Treatment of Atherosclerotic Popliteal Artery Lesions (ETAP) trial, Thomas Zeller, MD, of Universitäts-Herzzentrum Freiburg Bad Krozingen, Germany, and colleagues from nine European institutions randomized 246 patients with a single, de novo obstructive lesion in the popliteal artery to either a self-expanding nitinol stent (Lifestent, C.R. Bard; n=119) or standard balloon angioplasty (n=127).

Nitinol stent safe, effective

The 1-year primary patency rate derived by duplex ultrasound, which was the primary endpoint, was higher in the nitinol stent group compared with the angioplasty group (67.4% vs. 44.9%; P<.05). Post-procedure target lesion revascularization was greater in the angioplasty cohort compared with those treated with the nitinol stent, but when comparing the stent group with those who underwent optimal angioplasty, excluding patients with acute angioplasty failure. The comparison was no longer significant. There were no differences in any other clinical outcomes (see Figure).

Patients in the stent group also saw higher event-free survival (P<.0001) and improved walking distances at 1 year compared with the angioplasty group (116 m vs. 70 m; P< .05). Over the follow-up period, six patients died (2.4%) and two stent fractures (3.4%) were reported.

“The outcome of the trial is that stenting is safe,” Zeller said. “On the other hand, if an optimal balloon angioplasty [occurs] in the popliteal area, you can leave it without stenting. The outcome is almost as comparable.”

Going forward “you should start with a drug-coated balloon, and if [that does not work] then you would put in a BMS like the Lifestent or the (self-expanding nitinol) Supera stent (IDEV),” he concluded, adding that patients in the ETAP trial will be followed out to 2 years.

Discussant Erich Minar, MD, of the Medical University Vienna, Austria, congratulated the researchers on completing one of the only randomized trials on popliteal disease, but questioned the generalizability of the results and suggested that there might be other strategies used to avoid stenting.

Study details

The majority (64.2%) of patients were male with an average age of 72 years. Slightly more than a third had diabetes and slightly less than a quarter of patients were current smokers.