Passivated metallic implantable medical devices including radiopaque markers

Abstract

The present disclosure is directed to methods of manufacturing and passivating stents and other implantable medical devices including one or more attached radiopaque markers. In one embodiment, the method includes providing a metallic implantable medical device body without any radiopaque marker(s) attached thereto, primary electropolishing the device body without any markers attached thereto, attaching one or more radiopaque markers to the device body, and lightly electropolishing the device including device body and attached radiopaque markers. Light electropolishing removes no more than about 5 percent by weight of the device (i.e., the device body and attached marker(s)). Light electropolishing passivates the exposed surfaces of the device body and markers, while also providing electropolishing to the region of any welds where the radiopaque marker(s) attach to the device body.

What is claimed is: 
     
         1 . An implantable medical device including one or more radiopaque markers attached to a metallic implantable medical device body, the implantable medical device having been formed by a method comprising:
 providing the metallic implantable medical device body without any radiopaque markers attached thereto;   primary electropolishing the implantable medical device body;   attaching the one or more metallic radiopaque markers to the implantable medical device body, the one or more radiopaque markers comprising a metal that is different from that of the metallic implantable medical device body; and   lightly electropolishing the implantable medical device body with one or more attached radiopaque markers, the light electropolishing removing no more than about  5  percent by weight of the implantable medical device body including the one or more attached radiopaque markers;   wherein the light electropolishing of the implantable medical device body with one or more attached radiopaque markers passivates an exposed surface of the implantable medical device including the implantable medical device body and the one or more attached radiopaque markers.   
     
     
         2 . The implantable medical device of  claim 1  wherein the implantable medical device forms at least a portion of a device selected from the group consisting of a stent, a guide wire, a closure element, a pacemaker lead, an orthopedic device, an embolic coil, a suture, a prosthetic heart valve, a mitral valve repair coil, a filter, and combinations thereof. 
     
     
         3 . The implantable medical device of  claim 1 , wherein the one or more attached metallic radiopaque markers comprise a material selected from the group consisting of tantalum, gold, a platinum-uranium alloy, a platinum modified stainless steel, and combinations thereof. 
     
     
         4 . The implantable medical device of  claim 3 , wherein the one or more attached metallic radiopaque markers comprise tantalum. 
     
     
         5 . The implantable medical device of  claim 1  wherein the metallic implantable medical device body comprises a material selected from the group consisting of a nickel-titanium alloy, a cobalt-chromium alloy, stainless steel, a platinum modified stainless steel, and combinations thereof. 
     
     
         6 . The implantable medical device of  claim 1 , wherein the metallic implantable medical device body comprises a nickel-titanium alloy. 
     
     
         7 . The implantable medical device of  claim 1  wherein the implantable medical device body comprises a tubular stent body including a plurality of struts. 
     
     
         8 . The implantable medical device of  claim 1  wherein the implantable medical device is formed from sheet metal. 
     
     
         9 . The implantable medical device of  claim 1 , wherein the implantable medical device further comprises one or more weld interfaces where the one or more radiopaque markers are attached to the implantable medical device body, the one or more weld interfaces having a surface finish smoothness that is greater than would occur had the one or more weld interfaces not have been lightly electropolished. 
     
     
         10 . The implantable medical device of  claim 9 , wherein the one or more weld interfaces have a surface finish smoothness that is greater than would occur had the one or more weld interfaces been chemically passivated rather than lightly electropolished. 
     
     
         11 . A stent including one or more metallic radiopaque markers attached to a metallic tubular stent body, the stent having been formed by a method comprising:
 providing the metallic tubular stent body without any radiopaque markers attached thereto;   primary electropolishing the metallic tubular stent body;   attaching the one or more metallic radiopaque markers to the tubular stent body, the one or more radiopaque markers comprising a metal that is different from that of the metallic tubular stent body; and   lightly electropolishing the tubular stent body including the one or more attached radiopaque markers, the light electropolishing removing no more than about  5  percent by weight of the metallic tubular stent body with one or more attached radiopaque markers;   wherein the light electropolishing of the metallic tubular stent body with the one or more attached radiopaque markers passivates an exterior surface of the metallic tubular stent body with the one or more attached radiopaque markers.   
     
     
         12 . The stent of  claim 11 , wherein the one or more attached metallic radiopaque markers comprise a material selected from the group consisting of tantalum, gold, a platinum-uranium alloy, a platinum modified stainless steel, and combinations thereof. 
     
     
         13 . The stent of  claim 11  wherein the metallic tubular stent body comprises a material selected from the group consisting of a nickel-titanium alloy, a cobalt-chromium alloy, stainless steel, a platinum modified stainless steel, and combinations thereof. 
     
     
         14 . The stent of  claim 11 , wherein the metallic tubular stent body comprises a nickel-titanium alloy. 
     
     
         15 . The stent of  claim 11  wherein the tubular stent body includes a plurality of struts. 
     
     
         16 . The stent of  claim 11  wherein the tubular stent body is formed from sheet metal. 
     
     
         17 . The stent of  claim 11 , wherein the stent further comprises one or more weld interfaces where the one or more radiopaque markers are attached to the tubular stent body, the one or more weld interfaces having a surface finish smoothness that is greater than would occur had the one or more weld interfaces not have been lightly electropolished. 
     
     
         18 . The stent of  claim 17 , wherein the one or more weld interfaces have a surface finish smoothness that is greater than would occur had the one or more weld interfaces been chemically passivated rather than lightly electropolished. 
     
     
         19 . An implantable medical device including one or more radiopaque markers, the device comprising:
 a metallic implantable medical device body;   one or more metallic radiopaque markers attached to the implantable medical device body, the one or more radiopaque markers comprising a metal that is different from that of the metallic implantable medical device body; and   one or more weld interfaces attaching the one or more radiopaque markers to the implantable medical device body, wherein the one or more weld interfaces are both passivated and polished through light electropolishing so as to have a surface finish smoothness that is greater than an otherwise identical device where the weld interfaces have not been lightly electropolished.   
     
     
         20 . The implantable medical device of  claim 19 , wherein the one or more weld interfaces attaching the one or more radiopaque markers to the implantable medical device body have a surface finish smoothness that is greater than an otherwise identical device where the weld interfaces have been chemically passivated, but not lightly electropolished.