Drug-eluting bioabsorbable magnesium stent

Current stent technology is based on the use of permanent implants that remain life long in the vessel wall, far beyond the time required for the prosthesis to accomplish its main goals of sealing dissection and preventing wall recoil. With the possibility to implant long vessel segments using antiproliferative drugs to prevent restenosis, the practice of transforming the coronary vessels into stiff tubes with a full metal jacket covering all side branches and being unable to adjust to the long-term wall changes, including wall remodeling with lumen ectasia becomes a serious concern. In this article, we describe the first biodegradable stent based on a magnesium alloy that allows controlled corrosion with release to the vessel wall and the blood stream of a natural body component such as magnesium with beneficial antithrombotic, antiarrhythmic, and antiproliferative properties. We also discuss the animal experiments and the initial clinical applications in 20 patients with implants below the knee, with final results soon to be released, and the plans for the first coronary study. The results of these last two studies will indicate whether the absence of a permanent implant and the antiproliferative properties shown in animals are sufficient to prevent the restenotic process in humans or whether the prosthesis must be modified by adding the biodegradable coating with conventional antiproliferative drugs.