the implant the polymeric layer may then be bonded crimped heated melted shrink fitted or fused to the implant the polymeric layer may also be tied to the implant with a filament of for example a suture material still other techniques for attaching the polymeric layer include solvent swelling applications and extrusion processes wrapping a sheet of material about the implant or placing a tube of the material about the implant and securing the tube to the implant the polymeric layer may be secured on the interior of the implant by positioning a sheet or tube of material on the inside of the center section and securing the material therein the composition may also be formed of a fine mesh with a porosity or treatment such that tissue may not penetrate the pores for example a chronoflex u2122 dacron u00ae or teflon u00ae mesh having a pore size of 100 300 microns may be saturated with collagen or another biocompatible substance this construct may form a suitable polymeric layer the mesh may be coaxially attached to a frame such as the open frame structures disclosed above still other suitable frames include a continuous spiral metallic or polymeric element as discussed above the bio active substance or combination of bioactive substances is selected to assists in modifying the healing response as a result of the trauma to the lung.