EuroPCR: Novel Metal Stent Does Disappearing Act
By Crystal Phend, Senior Staff Writer,
MedPage TodayPublished: May 19, 2011Reviewed by
Zalman S. Agus, MD; Emeritus Professor University of Pennsylvania School of Medicine andDorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner
PARIS -- A novel drug-eluting stent may do away with the permanent metal jacket, according to early results with a bioabsorbable metal scaffold.The paclitaxel-eluting magnesium alloy stent degrades away after about nine months to a soft hydroxyapatite absorbed by the body, Michael Haude, MD, of Städtische Kliniken Neuss Lukaskrankenhaus in Neuss, Germany, and colleagues reported.First-in-man results suggested a 9.1% target lesion failure rate -- two revascularizations -- and 0.68 mm late lumen loss at six months in a small, 22-patient study Haude presented here at the European Society of Cardiology's EuroPCR meeting."We feel that we are on the right direction," Haude told MedPage Today at a press conference.
Bioabsorbable
polymer scaffold stents have been developed as well, but a metal backbone holds clear advantages for conforming to the vessel, Haude explained.
"It is really adapting to the vessel size, and, of course, you can overstress it, you can dilate it, which is not to that extent possible with most of the polymers that are on the market," he said at the session.
While the novel technology still needs to prove itself against conventional drug-eluting stents, there would likely be advantages for treating younger patients in earlier stages of coronary artery disease, he suggested.
These patients with decades of life expectancy "obviously don't want to have a permanent scaffold stent within their arteries for the rest of their life," Haude told attendees.
The researchers tweaked the design of the stent, adding a bioabsorbable paclitaxel-eluting polymer coating and extending the scaffold degradation time, then tested it in 46 patients with de novo coronary artery stenosis in the BIOSOLVE-I study.
The 22 patient cohort with clinical follow-up at six months showed 100% procedural and technical successes. No deaths, heart attacks, or scaffold thrombosis were seen, though two patients required clinically driven target lesion revascularization by six months due to angina.
The in-scaffold late lumen loss was 0.68 mm at six months, which was a 37% improvement over results with the prior bare metal version of the stent. The 9.1% target lesion revascularization rate was a 62% improvement over results with the prior version.
The second cohort, which will have a 12-month follow-up, should provide additional information on long-term safety and efficacy of the new scaffold, Haude noted.
By comparison, first-in-man trials with conventional stents had reported late lumen loss of 0.10 with the Xience V stent, 0.09 mm with Cypher, and 0.12 mm with Endeavor, as Martial Hamon, MD, of the University Hospital of Caen in Normandy, France, noted in a separate presentation at the session.
Also for comparison purposes, at six months the late lumen loss was 0.44 mm and the restenosis rate was 11.5% for the first-in-man trial of an
everolimus-eluting polymer bioabsorbable coronary stent. The study was sponsored by Biotronik.
Haude reported research contracts with Biotronik, OrbusNeich, Cordis, Medtronic, Cardiac Dimensions, and Volcano as well as consulting for Biotronik and OrbusNeich.
Hamon reported consulting for Biotronik.
Primary source: European Association of Percutaneous Cardiovascular InterventionsSource reference:Haude M, et al "BIOSOLVE-I safety and clinical performance of the first drug-eluting absorbable metal scaffold" EuroPCR 2011.
