Fiber reinforced composite stents

Abstract

Polymeric composite stents reinforced with fibers for implantation into a bodily lumen are disclosed.

1 . A method of making a stent comprising: 
 forming a mixture comprising a matrix polymer and a plurality of short fibers, the fibers comprising a material having a melting temperature greater than a melting temperature of the matrix polymer;    disposing the mixture in a tube or sheet forming apparatus to form a tube or a sheet, wherein the apparatus is heated so that a temperature of the mixture in the apparatus is greater than the melting temperature of the matrix polymer and less than the melting temperature of the material of the fibers such that at least a portion of the matrix polymer is a polymer melt; and    fabricating a stent from the tube or sheet comprising the matrix polymer and the short fibers.    
     
     
         2 . The method of  claim 1 , wherein the matrix polymer comprises a biodegradable polymer.  
     
     
         3 . The method of  claim 1 , wherein the material of the fibers comprises a biodegradable polymer.  
     
     
         4 . The method of  claim 1 , wherein the material of the fibers comprises a biostable and/or erodible metal.  
     
     
         5 . The method of  claim 1 , wherein the material of the fibers comprises a radiopaque material.  
     
     
         6 . The method of  claim 1 , wherein the mixture comprises an active agent.  
     
     
         7 . The method of  claim 1 , wherein at least some of the fibers comprise an active agent.  
     
     
         8 . The method of  claim 1 , wherein a length of at least a portion of the short fibers is substantially smaller than a length of the formed tube.  
     
     
         9 . The method of  claim 1 , wherein the mixture is formed in a mixing apparatus at a temperature greater than the melting temperature of the matrix polymer and less than the melting temperature of the material of the fibers.  
     
     
         10 . The method of  claim 1 , wherein the tube comprises forming a tube or a sheet by injection molding.  
     
     
         11 . The method of  claim 1 , wherein forming the tube comprises extruding a tube or a sheet from the mixture.  
     
     
         12 . The method of  claim 1 , wherein the formed tube or sheet is cooled to a temperature below the melting temperature of the matrix polymer such that a majority of the matrix polymer in the formed tube is amorphous, crystalline, or partially crystalline.  
     
     
         13 . The method of  claim 1 , wherein fabricating a stent comprises forming a pattern on the formed tube comprising a plurality of interconnecting structural elements.  
     
     
         14 . The method of  claim 1 , wherein fabricating a stent comprises forming a tube from the sheet and forming a pattern on the formed sheet comprising a plurality of interconnecting structural elements.  
     
     
         15 . The method of  claim 1 , further comprising radially deforming the tube comprising the matrix polymer and the short fibers to increase circumferential strength and rigidity of the tube and/or to increase the circumferential alignment of at least some of the fibers.  
     
     
         16 . A stent made according to the method of  claim 1 .  
     
     
         17 . A method of making a stent comprising: 
 forming a tube comprising at least one fiber layer and at least one polymer film layer, fibers of at least one fiber layer comprising a material having a melting temperature greater than a melting temperature of at least one polymer film layer;    heating the tube to a temperature greater than the melting temperature of at least one polymer film layer and less than the melting temperature of the material of the fibers to melt at least a portion of the polymer of at least one polymer film layer, at least a portion of at least one fiber layer becoming embedded within at least a portion of the melted polymer of at least one polymer film layer;    cooling the heated tube; and    fabricating a stent from the cooled tube.    
     
     
         18 . The method of  claim 17 , wherein at least one polymer film layer comprises a biodegradable polymer.  
     
     
         19 . The method of  claim 17 , wherein the material of the fibers of at least one fiber layer comprises a biodegradable polymer.  
     
     
         20 . The method of  claim 17 , wherein the material of the fibers of at least one fiber layer comprises a biostable and/or erodible metal.  
     
     
         21 . The method of  claim 17 , wherein the material of the fibers of at least one fiber layer comprises a radiopaque material.  
     
     
         22 . The method of  claim 17 , wherein at least one fiber layer alternates with at least one film layer.  
     
     
         23 . The method of  claim 17 , wherein at least one fiber layer comprises a woven structure.  
     
     
         24 . The method of  claim 17 , wherein at least one of the polymer film layers comprises an active agent.  
     
     
         25 . The method of  claim 17 , wherein at least some of the fibers comprise an active agent.  
     
     
         26 . The method of  claim 17 , wherein forming the tube comprises disposing at least one layer on a mandrel.  
     
     
         27 . The method of  claim 17 , wherein the heated tube is cooled to a temperature below the melting temperature of at least one polymer film layer such that a majority of the polymer that was melted becomes amorphous, crystalline, or partially crystalline.  
     
     
         28 . The method of  claim 17 , wherein fabricating a stent comprises forming a pattern on the tube comprising a plurality of interconnecting structural elements.  
     
     
         29 . The method of  claim 17 , further comprising radially deforming the heated tube to increase circumferential strength and rigidity of the tube.  
     
     
         30 . The method of  claim 17 , wherein an orientation of fibers relative to a cylindrical axis of the tube of at least one fiber layer may be different from an orientation of fibers in another fiber layer.  
     
     
         31 . The method of  claim 17 , wherein an orientation of fibers relative to a cylindrical axis of the tube in at least one fiber layer is greater than 90° and an orientation of fibers in another fiber layer is less than 90°.  
     
     
         32 . A stent made according to the method of  claim 17 .  
     
     
         33 . A method of making a stent comprising: 
 forming a layered sheet comprising at least one fiber layer and at least one polymer film layer, fibers of at least one fiber layer comprising a material having a melting temperature greater than a melting temperature of at least one polymer film layer;    heating the layered sheet to a temperature greater than the melting temperature of at least one polymer film layer and less than the melting temperature of the material of the fibers to melt at least a portion of the polymer of at least one polymer film layer, at least a portion of the fibers becoming embedded within at least a portion of the melted polymer of at least one polymer film layer;    cooling the heated layered sheet; and    fabricating a stent from the cooled sheet.    
     
     
         34 . The method of  claim 33 , wherein at least one polymer film layer comprises a biodegradable polymer.  
     
     
         35 . The method of  claim 33 , wherein the material of the fibers of at least one fiber layer comprises a biodegradable polymer.  
     
     
         36 . The method of  claim 33 , wherein the material of the fibers of at least one fiber layer comprises a biostable and/or erodible metal.  
     
     
         37 . The method of  claim 33 , wherein the material of the fibers of at least one fiber layer comprises a radiopaque material.  
     
     
         38 . The method of  claim 33 , wherein at least one fiber layer alternates with at least one polymer film layer.  
     
     
         39 . The method of  claim 33 , wherein fabricating the stent comprises forming a tube from the layered sheet and forming a pattern on the tube and/or the layered sheet comprising a plurality of interconnecting structural elements.  
     
     
         40 . The method of  claim 33 , wherein at least one of the polymer film layers comprises an active agent.  
     
     
         41 . The method of  claim 33 , wherein at least some of the fibers comprise an active agent.  
     
     
         42 . The method of  claim 33 , further comprising cooling the heated layered sheet.  
     
     
         43 . The method of  claim 33 , wherein the fibers are nanofibers.  
     
     
         44 . The method of  claim 33 , wherein the heated sheet is cooled to a temperature below the melting temperature of the polymer films such that a majority of the polymer that was melted becomes amorphous, crystalline and/or partially crystalline.  
     
     
         45 . The method of  claim 33 , wherein fabricating a stent comprises forming a pattern on the sheet comprising a plurality of interconnecting structural elements and forming a tube from the sheet.  
     
     
         46 . The method of  claim 33 , wherein fabricating a stent comprises forming a tube from the sheet and forming a pattern on the sheet comprising a plurality of interconnecting structural elements.  
     
     
         47 . A stent made according to the method of  claim 33 .  
     
     
         48 . A method of making a stent comprising: 
 forming a coating layer comprising a coating polymer over a tube-shaped fiber layer comprising a plurality of fibers, wherein the coating layer is formed by applying a fluid comprising the coating polymer dissolved in a solvent and by removing all or a majority of the solvent from the applied fluid, the fibers comprising a material being insoluble or having a relatively low solubility in the solvent, the material comprising a melting temperature greater than a melting temperature of the coating polymer; and    fabricating a stent from the coated fiber layer.    
     
     
         49 . The method of  claim 48 , wherein the coating polymer comprises a biodegradable polymer.  
     
     
         50 . The method of  claim 48 , wherein the material of the fibers of at least one fiber layer comprises a biodegradable polymer.  
     
     
         51 . The method of  claim 48 , wherein the material of the fibers comprises a biostable and/or erodible metal.  
     
     
         52 . The method of  claim 48 , wherein the material of the fibers comprises a radiopaque material.  
     
     
         53 . The method of  claim 48 , wherein the coating layer comprises an active agent.  
     
     
         54 . The method of  claim 48 , wherein at least some of the fibers comprise an active agent.  
     
     
         55 . The method of  claim 48 , wherein the tube-shaped fibers layer comprises a woven structure.  
     
     
         56 . The method of  claim 48 , wherein applying the fluid comprises spraying the fluid on and/or dipping the tube into the solvent.  
     
     
         57 . The method of  claim 48 , further comprising heating the coating layer to a temperature above the melting temperature of the coating polymer and cooling the coating layer to a temperature below the melting temperature of the coating polymer so that a majority of the coating layer is amorphous, crystalline, and/or partially crystalline.  
     
     
         58 . The method of  claim 48 , further comprising radially deforming the coated tube to increase circumferential strength and rigidity of the tube.  
     
     
         59 . The method of  claim 48 , wherein the fiber layer is disposed on a mandrel.  
     
     
         60 . The method of  claim 48 , wherein the fiber layer is disposed on a mandrel over a coating layer comprising the coating polymer.  
     
     
         61 . A stent made according to the method of  claim 48 .  
     
     
         62 . A method of making a stent comprising: 
 disposing a plurality of fibers within a mold for forming a structure;    disposing a matrix polymer that is partially or completely molten into the mold to at least partially embed the fibers within the molten polymer, the fiber comprising a material having a melting temperature greater than a melting temperature of the matrix polymer, wherein a temperature of the matrix polymer and the fibers in the mold is less than the melting temperature of the fiber material;    cooling the molten polymer to form the structure; and    fabricating a stent from the cooled structure.    
     
     
         63 . The method of  claim 62 , wherein the matrix polymer comprises a biodegradable polymer.  
     
     
         64 . The method of  claim 62 , wherein the material of the fibers comprises a biodegradable polymer.  
     
     
         65 . The method of  claim 62 , wherein the material of the fibers comprises a biostable and/or erodible metal.  
     
     
         66 . The method of  claim 62 , wherein the material of the fibers comprises a radiopaque material.  
     
     
         67 . The method of  claim 62 , wherein the material of the fibers comprises a biodegradable polymer.  
     
     
         68 . The method of  claim 62 , wherein the material of the fibers comprises a biostable and/or erodible metal.  
     
     
         69 . The method of  claim 62 , wherein the material of the fibers comprises a radiopaque material.  
     
     
         70 . The method of  claim 62 , further comprising disposing an active agent into the mold.  
     
     
         71 . The method of  claim 62 , wherein at least some of the fibers comprise an active agent.  
     
     
         72 . The method of  claim 62 , wherein disposing the fibers within a mold comprises disposing the fibers around a mandrel disposed within the mold.  
     
     
         73 . The method of  claim 62 , wherein disposing the fibers within a mold in a random or substantially random fashion.  
     
     
         74 . The method of  claim 62 , wherein the structure comprises a tube or a sheet.  
     
     
         75 . The method of  claim 62 , wherein the structure comprises a sheet, and wherein fabricating a stent comprises forming a tube from the sheet and forming a pattern in the tube comprising a plurality of interconnecting structural elements.  
     
     
         76 . The method of  claim 62 , wherein the structure comprises a tube, and wherein fabricating a stent comprises forming a pattern on the tube comprising a plurality of interconnecting structural elements.  
     
     
         77 . The method of  claim 62 , wherein the structure is cooled to a temperature below the melting temperature of the matrix polymer such that a majority of the matrix polymer in the formed structure is amorphous, crystalline, and/or partially crystalline.  
     
     
         78 . The method of  claim 62 , wherein the structure comprises a tube, and further comprising radially deforming the formed tube to increase circumferential strength and rigidity of the tube.  
     
     
         79 . A stent made according to the method of  claim 68 .  
     
     
         80 . A method of making a stent comprising: 
 disposing a plurality of fibers in an extruder for forming a structure;    conveying a matrix polymer into the extruder, the fibers comprising a material having a melting temperature greater than a melting temperature of the matrix polymer;    forming the structure with the extruder at a temperature greater than the melting temperature of the matrix polymer and less than the melting temperature of the material, wherein at least some of the fibers becoming embedded within the matrix polymer; and    fabricating a stent from the cooled structure.    
     
     
         81 . The method of  claim 80 , wherein the matrix polymer comprises a biodegradable polymer.  
     
     
         82 . The method of  claim 80 , wherein the material of the fibers comprises a biodegradable polymer.  
     
     
         83 . The method of  claim 80 , wherein the material of the fibers comprises a biostable and/or erodible metal.  
     
     
         84 . The method of  claim 80 , wherein the material of the fibers comprises a radiopaque material.  
     
     
         85 . The method of  claim 80 , further comprising conveying an active agent into the extruder.  
     
     
         86 . The method of  claim 80 , wherein at least some of the fibers comprise an active agent.  
     
     
         87 . The method of  claim 80 , wherein disposing the plurality of fibers in the extruder comprises disposing the fibers around a mandrel.  
     
     
         88 . The method of  claim 80 , wherein disposing the plurality of fibers in the extruder comprises disposing the fibers in the extruder in a random or substantially random fashion.  
     
     
         89 . The method of  claim 80 , wherein the structure comprises a sheet, and wherein fabricating a stent comprises forming a tube from the sheet and forming a pattern in the tube comprising a plurality of interconnecting structural elements.  
     
     
         90 . The method of  claim 80 , wherein the structure comprises a tube, and wherein fabricating a stent comprises forming a pattern in the tube comprising a plurality of interconnecting structural elements.  
     
     
         91 . The method of  claim 80 , wherein the structure is cooled to a temperature below the melting temperature of the matrix polymer such that a majority of the matrix polymer in the formed structure is amorphous, crystalline, or partially crystalline.  
     
     
         92 . The method of  claim 80 , wherein the structure comprises a tube, and further comprising radially deforming the formed tube to increase circumferential strength and rigidity of the tube.  
     
     
         93 . A stent made according to the method of  claim 80 .  
     
     
         94 . A method of making a stent comprising: 
 heating a fiber mesh tube comprising two types of fibers, a first fiber comprising a first polymer and the second fiber comprising a second polymer, the first polymer having a softening temperature lower than a softening temperature of the second polymer, wherein the tube is heated to a temperature range between the softening temperature of the first polymer and the softening temperature of the second polymer; and    applying pressure to the tube so as to flatten at least some of the fibers of the tube to reduce a radial profile of the tube.    
     
     
         95 . The method of  claim 94 , wherein the first polymer comprises a biostable and/or biodegradable polymer.  
     
     
         96 . The method of  claim 94 , wherein the second polymer comprises a biostable and/or biodegradable polymer.  
     
     
         97 . The method of  claim 94 , wherein the tube is disposed over a mandrel during heating.  
     
     
         98 . The method of  claim 94 , wherein pressure is applied with a heated crimper.  
     
     
         99 . The method of  claim 94 , wherein the diameter of the tube is fixed during heating.  
     
     
         100 . The method of  claim 94 , wherein the tube is heated and pressure applied at or near a fabricated diameter of the tube.  
     
     
         101 . The method of  claim 94 , wherein the temperature of the tube is maintained in the temperature range for a selected period of time to allow heat setting of the tube.  
     
     
         102 . The method of  claim 94 , further comprising radially expanding the tube prior to, during, or subsequent to heating and/or applying pressure to flatten at least some of the fibers.  
     
     
         103 . The method of  claim 94 , wherein the first polymer has a lower melting temperature than the second polymer.  
     
     
         104 . The method of  claim 94 , wherein the temperature range is below the melting temperature of the first polymer and the second polymer.  
     
     
         105 . The method of  claim 94 , wherein the temperature range is below the glass transition temperature the second polymer.  
     
     
         106 . The method of  claim 94 , wherein the applied pressure reduces a radial profile of at least some of the net points of the fibers.  
     
     
         107 . A stent made according to the method of  claim 94 .  
     
     
         108 . A method of making a stent comprising: 
 heating a fiber mesh tube, at least some of the fibers of the tube comprising a first polymer and a second polymer, the first polymer having a softening temperature lower than a softening temperature of the second polymer, wherein the tube is heated to a temperature range between the softening temperature of the first polymer and the softening temperature of the second polymer; and    applying pressure to the tube so as to flatten at least some of the fibers of the tube to reduce a radial profile of the tube.    
     
     
         109 . The method of  claim 108 , wherein at least some of the fibers of the tube comprise an inner core and an outer covering, the inner core comprising the first polymer and the outer covering comprising the second polymer.  
     
     
         110 . The method of  claim 108 , wherein at least some of the fibers of the tube comprise a mixture of the first polymer and the second polymer.  
     
     
         111 . The method of  claim 108 , wherein the first polymer comprises a biostable and/or biodegradable polymer.  
     
     
         112 . The method of  claim 108 , wherein the second polymer comprises a biostable and/or biodegradable polymer.  
     
     
         113 . The method of  claim 108 , wherein the tube is disposed over a mandrel during heating.  
     
     
         114 . The method of  claim 108 , wherein pressure is applied with a heated crimper.  
     
     
         115 . The method of  claim 108 , wherein the diameter of the tube is fixed during heating.  
     
     
         116 . The method of  claim 108 , wherein the tube is heated and pressure applied at or near a fabricated diameter of the tube.  
     
     
         117 . The method of  claim 108 , wherein the temperature of the tube is maintained in the temperature range for a selected period of time to allow heat setting of the tube.  
     
     
         118 . The method of  claim 108 , further comprising radially expanding the tube prior to, during, or subsequent to heating and/or applying pressure to flatten at least some of the fibers.  
     
     
         119 . The method of  claim 108 , further comprising crimping the tube prior to, during, or subsequent to heating the tube and/or applying pressure to flatten at least some of the fibers.  
     
     
         120 . The method of  claim 108 , wherein the first polymer has a lower melting temperature than the second polymer.  
     
     
         121 . The method of  claim 108 , wherein the temperature range is below the melting temperature of the first polymer and the second polymer.  
     
     
         122 . The method of  claim 108 , wherein the temperature range is below the glass transition temperature of the second polymer.  
     
     
         123 . The method of  claim 108 , wherein the applied pressure reduces a radial profile of at least some of the net points of the fibers.  
     
     
         124 . A stent made according to the method of  claim 108 .  
     
     
         125 . A method of making a stent comprising: 
 coupling a metallic film to at least a portion of a surface of a polymeric tube; and    fabricating a stent from the tube with the metallic film so that the metallic film is over at least a portion of a surface of the stent.    
     
     
         126 . The method of  claim 125 , wherein the metallic film comprises a biostable and/or erodible metal.  
     
     
         127 . The method of  claim 125 , further comprising forming a coating above at least a portion of the metallic film above a portion of the surface of the stent.  
     
     
         128 . The method of  claim 125 , wherein the metallic film is coupled to at least a portion of a surface of a polymeric tube with a biocompatible adhesive.  
     
     
         129 . The method of  claim 125 , wherein the polymeric tube comprises a biostable and/or biodegradable polymer.  
     
     
         130 . The method of  claim 125 , wherein the metallic film comprises a band circumferentially aligned around a surface of the tube.  
     
     
         131 . The method of  claim 125 , wherein the metallic film comprises a longitudinal strip longitudinally aligned along the surface of the tube.  
     
     
         132 . The method of  claim 125 , wherein fabricating the stent comprises forming a pattern in the tube having the metallic film, the pattern comprising a plurality of interconnecting structural elements.  
     
     
         133 . A stent made according to the method of  claim 125 .  
     
     
         134 . A method of making a stent comprising: 
 forming a tube having a metallic film in between two radial polymeric layers; and    fabricating a stent from the tube.    
     
     
         135 . The method of  claim 134 , wherein the tube is formed by extruding an outer polymeric tubular layer over an inner polymeric tubular layer, the inner layer comprising a metallic film disposed above a surface of the inner layer.  
     
     
         136 . The method of  claim 134 , wherein the polymeric layers comprise a biostable and/or biodegradable polymer.  
     
     
         137 . The method of  claim 134 , wherein the metallic film comprises a biostable and/or erodible metal.  
     
     
         138 . The method of  claim 134 , wherein the metallic film comprises a band circumferentially aligned around a circumference of the tube in between the layers.  
     
     
         139 . The method of  claim 134 , wherein the metallic film comprises a longitudinal strip longitudinally aligned along the tube in between the polymer layers.  
     
     
         140 . The method of  claim 134 , wherein fabricating the stent comprises forming a pattern in the tube, the pattern comprising a plurality of interconnecting structural elements.  
     
     
         141 . A stent made according to the method of  claim 134 .  
     
     
         142 . A method of making a stent comprising: 
 elongating a polymeric tube so that a diameter of the stent decreases;    positioning a metallic band around a circumference of the elongated tube;    heating the elongated polymeric tube with the metallic band positioned around the tube;    allowing the heated tube to radially expand so as to couple the metallic band to the tube; and    fabricating a stent from the expanded tube.    
     
     
         143 . The method of  claim 142 , wherein the metallic band comprises a biostable and/or erodible metal.  
     
     
         144 . The method of  claim 142 , wherein the heated tube radially expands to at least a diameter of the metallic band.  
     
     
         145 . The method of  claim 142 , wherein the polymeric tube comprises a biostable and/or biodegradable polymer.  
     
     
         146 . The method of  claim 142 , wherein fabricating the stent comprises forming a pattern in the expanded tube, the pattern comprising a plurality of interconnecting structural elements.  
     
     
         147 . A stent made according to the method of  claim 142 .  
     
     
         148 . A radially expandable stent comprising a plurality of interconnecting structural elements, the structural elements comprising fibers at least partially embedded in a matrix polymer, the fibers including a material having a melting temperature greater than a melting temperature of the matrix polymer, the fibers configured to provide mechanical reinforcement to the stent due to a higher strength and modulus along an axis of the fibers than the matrix polymer.  
     
     
         149 . A radially expandable stent comprising a plurality of interconnecting structural elements, the structural elements comprising at least one radial fiber layer and at least one radial polymer film layer, the fibers including material with a melting temperature greater than a melting temperature than at least one polymer film layer, at least one fiber layer being at least partially embedded within at least one polymer film layer, the fibers configured to provide mechanical reinforcement to the stent due to a higher strength and modulus along an axis of the fibers than the polymer film layer.  
     
     
         150 . A radially expandable stent comprising a plurality of structural elements, the structural elements comprising at least two radial fiber layers and at least one radial polymer film layer, at least a portion of at least one fiber layer being embedded within at least a portion of at least one polymer film layer, wherein an orientation of fibers relative to a cylindrical axis of the stent of at least one fiber layer is different from an orientation of fibers in another fiber layer.  
     
     
         151 . The stent of  claim 150 , wherein the orientation of fibers relative to the cylindrical axis of the stent in at least one fiber layer is greater than 90° and an orientation of fibers in another fiber layer is less than 90°.  
     
     
         152 . A radially expandable stent woven from at lease two types of fibers, a first fiber comprising a first polymer and the second fiber comprising a second polymer, the first polymer having a softening temperature lower than a softening temperature of the second polymer, wherein at least some of the fibers have a flattened radial profile that reduces the radial profile of the tube.  
     
     
         153 . A radially expandable stent woven from fibers comprising a first polymer and a second polymer, the first polymer having a softening temperature lower than a softening temperature of the second polymer, wherein at least some of the fibers have a flattened radial profile that reduces the radial profile of the tube.  
     
     
         154 . A radially expandable stent comprising metallic film coupled to a plurality of portions of a surface of the stent, wherein the metallic film is sufficiently radiopaque to allow the stent to be visualized during use.  
     
     
         155 . The device of  claim 153 , wherein the metallic film comprises a biostable and/or erodible metal.  
     
     
         156 . The device of  claim 153 , further comprising a coating above at least some of the plurality of portions of the surface having the metallic film.  
     
     
         157 . The device of  claim 153 , wherein the polymeric tube comprises a biostable and/or biodegradable polymer.  
     
     
         158 . The device of  claim 153 , wherein the plurality of portions are circumferentially aligned.  
     
     
         159 . The device of  claim 153 , wherein the plurality of portions are longitudinally aligned.  
     
     
         160 . A radially expandable stent comprising a plurality of interconnecting structural elements, the structural elements having two radial polymeric layers with metallic film embedded in a plurality of locations in between the layers, and wherein the metallic film is sufficiently radiopaque to allow the stent to be visualized during use.  
     
     
         161 . The device of  claim 160 , wherein the polymer layers comprise a biostable and/or biodegradable polymer.  
     
     
         162 . The device of  claim 160 , wherein the metallic film comprises a biostable and/or erodible metal.  
     
     
         163 . The device of  claim 160 , wherein the plurality of portions are circumferentially aligned.  
     
     
         164 . The device of  claim 160 , wherein the plurality of portions are longitudinally aligned.