摘要 |
<p>An implantable medical device comprises: an implantable device body having a mural surface (26) and a luminal surface (24) and a plurality of holes (20) traversing both the mural and luminal surface; a therapeutic agent, a matrix (40), and a barrier layer (30) contained in each of the plurality of holes; wherein the holes each have a luminal opening and a mural opening and the barrier layer is positioned across the luminal opening, and the therapeutic agent is primarily delivered through the mural opening of the hole; wherein the therapeutic agent is present in both the barrier layer and the matrix, at different local concentrations, and the matrix is created in a stepwise manner, such that a concentration gradient of the therapeutic agents exists in the matrix.</p> |