Multilayered metal stent

Abstract

Coated stents for increased radiopacity. In one embodiment, the present invention includes a stent in the form of a tubular member comprising struts of a first material, and a first coating on the tubular member. The first coating substantially covers the tubular member and is substantially uniform in thickness. The first coating comprises a second material that is more radiopaque than the first material. In another embodiment, the stent further comprises a second coating between the tubular member and the first coating, wherein the second coating covers only a portion of the tubular member. In yet another embodiment, the stent is a coated bifurcated stent for positioning in a bifurcated body lumen.

What is claimed is:  
     
         1 . A stent for deploying within a body lumen, said stent comprising: 
 a tubular member comprising struts which comprise a first material, said tubular member having a proximal end and a distal end and a longitudinal bore therethrough; and    a first coating on said tubular member, said first coating substantially covering said tubular member and being substantially uniform in thickness, said first coating comprising a second material;    wherein said second material is more radiopaque than said first material.    
     
     
         2 . The stent of  claim 1 , wherein the thickness of said first coating is approximately 1-20 percent of the thickness of an underlying strut.  
     
     
         3 . The stent of  claim 2 , wherein the thickness of the first coating is approximately 5-15 percent of the thickness of an underlying strut.  
     
     
         4 . The stent of  claim 1 , wherein said first coating is approximately 0.5-20 microns in thickness.  
     
     
         5 . The stent of  claim 1 , wherein said first material is selected from the group consisting of stainless steel and nitinol.  
     
     
         6 . The stent of  claim 1 , wherein said second material is selected from the group consisting of gold, platinum, silver and tantalum.  
     
     
         7 . The stent of  claim 1 , further comprising a second coating disposed between said tubular member and said first coating, said second coating covering only a portion of said tubular member.  
     
     
         8 . The stent of  claim 7 , wherein said second coating is located at said proximal or said distal end of said tubular member.  
     
     
         9 . The stent of  claim 7 , wherein when the stent is observed with fluoroscopy, said stent appears darker at the portion where said second coating exists than where said second coating does not exist.  
     
     
         10 . The stent of  claim 7 , wherein the thickness of said second coating is approximately 1-20 percent of the thickness of an underlying strut.  
     
     
         11 . The stent of  claim 10 , wherein the thickness of the second coating is approximately 5-15 percent of the thickness of an underlying strut.  
     
     
         12 . The stent of  claim 7 , wherein said second coating is approximately 0.5-20 microns in thickness.  
     
     
         13 . The stent of  claim 12 , wherein said second coating is approximately 5-15 microns in thickness.  
     
     
         14 . The stent of  claim 12 , wherein said first coating is approximately 1 micron in thickness.  
     
     
         15 . The stent of  claim 7 , wherein said second coating comprises a material selected from the group consisting of gold, platinum, silver and tantalum.  
     
     
         16 . The stent of  claim 1 , wherein said tubular member is bifurcated into a trunk leg and a branch leg for positioning in respective trunk and branch lumens of a bifurcated lumen.  
     
     
         17 . The stent of  claim 16 , further comprising a second coating between said tubular member and said first coating, said second coating covering only said branch leg.  
     
     
         18 . The stent of  claim 16 , wherein: 
 said tubular member includes a branch aperture;    said branch leg may be selectively disposed within said tubular member; and    a region of said tubular member adjacent to said branch aperture includes a second coating between said tubular member and said first coating.