Method and apparatus for treating vulnerable coronary plaques using drug-eluting stents

摘要

A drug-eluting intravascular stent comprising an anti-restenosis agent covered by a biodegradable coating, and a method for treating vulnerable plaque in coronary vessels using said stent is disclosed. The biodegradable layer covers at least a portion of the drug-eluting layer of the stent, and is adapted to slowly erode over a preset period of time, preventing the release of therapeutic amounts of the anti-restenosis agent from the drug-eluting layer during the preset period. By delaying the release of the anti-restenosis agent, a thin layer of neointima will grow during the preset period. This tissue growth is sufficient to encapsulate the stent and cover the vulnerable plaque, but not significant enough to cause harmful restenosis or occlusion of the vessel. Once the biodegradable coating is eroded, the anti-restenosis agent begins release from the drug-eluting layer, and the progression of neointimal hyperplasia ceases.