An implantable device having a coating comprising a comb-type anti-thrombotic conjugate to prevent or reduce the formation of thrombosis on the surface of the device. The device includes a frame expandable from a first diameter to a second diameter wherein the frame has an inner surface and an outer surface, a plurality of structural features disposed along the frame and a plurality of polymer anti-thrombotic conjugate particles situated with the plurality of structural features. The particle can be created utilizing the comb type polymer and heparin conjugate as a carrier for a therapeutic agent within its polymer matrix. The structural features allow for particles having differing properties to be placed at various locations along the device. Moreover, particles having at least two different agents can be located within the same structural feature.
