December 27, 2012 — A dozen years ago, controversial clinical trial results caused an international medical society to warn against the use of stents in leg arteries. But recent years have brought significant improvements in stent technology. One-year follow-up results of a worldwide, multicenter trial with 744 patients show that 90 percent of participants had successful procedures that did not require a repeat treatment.
The current issue of the Journal of Endovascular Therapy presents results of a clinical trial of the Misago self-expanding rapid-exchange nitinol stent system. The MISAGO 2 study included 744 patients with at least 70 percent occlusion of the femoral or popliteal arteries who were treated in 76 medical centers worldwide. Success of the procedures was assessed at six and 12 months following stent placement.
The use of balloon angioplasty in the peripheral arteries has proven safe and effective — at least in the short term. High plaque burden, low blood flow velocities and lesion length present obstacles to the success of this technique. The additional placement of a stent can prevent recoil of the dilated vessel, limit residual stenosis, and decrease the risk of dissection.
Since the 2000 TransAtlantic Inter-Society Consensus Working Group discouraged femoropopliteal stenting as a primary therapy, much progress has been made. In several clinical trials, self-expanding nitinol stents have shown improved intermediate outcomes.
At the one-year follow-up, the MISAGO 2 study found an overall revascularization rate of 10 percent. Event-free survival was 85 percent. Significant improvements were noted for patients’ ischemic symptoms and pain-free walking distances. With a low incidence of complications, the study raised no safety concerns for use of the Misago system.
The authors of an accompanying commentary discuss strengths and weaknesses of this research and point out that other clinical trials have had similar positive results. A number of stents have shown efficacy, and a number of alternative technologies, including drug-eluting stents and balloons, are now available. The authors conclude that “the time has come for comparative trials with clinically meaningful outcomes.”
Full text of the article, “MISAGO 2: One-Year Outcomes After Implantation of the Misago Self-Expanding Nitinol Stent in the Superficial Femoral and Popliteal Arteries of 744 Patients,” and commentary article, Journal of Endovascular Therapy, Vol. 19, No. 6, 2012, are available at www.jevt.org/toc/enth/19/6.