Method and intravascular stent for reducing complications after implantation of an intravascular stent

Abstract

This invention relates to methods and arrangement for reducing complications after implantation of an intravascular stent and, more particularly, for reducing the risk of restenosis due to stent implantation. This is achieved by using 17beta-estradiol as vessel healing substance after implantation of an intravascular stent. The 17beta-estradiol can be coated onto an intravascular stent and be included in a drug elution system applied to the intravascular stent. This can be achieved by means of a surface coating process such as CVD process. 17beta-estradiol inhibits the growth of smooth muscle cells and stimulates the re-endothelialization after implantation of an intravascular stent. The present invention makes use of these effects in order to prevent restenosis and in-stent stenosis.

I claim:  
     
         1 . A method for reducing complications after implantation of an intravascular stent, comprising the steps of: 
 inserting an intravascular stent into a vessel to a site of intravascular stent placement at a site of vessel stenosis; and    supplying 17beta-estradiol to said site of intravascular stent placement.    
     
     
         2 . The method of  claim 1 , wherein said supply of 17beta-estradiol is effected during an operation for implantation of said intravascular stent into said vessel.  
     
     
         3 . The method of  claim 2 , wherein said supply of 17beta-estradiol is effected simultaneous with said implantation of said intravascular stent into said vessel.  
     
     
         4 . The method of  claim 1 , wherein said 17beta-estradiol is supplied in a certain quantity and said quantity is chosen in dependence of the estimated healing time of said vessel after implantation of said intravascular stent.  
     
     
         5 . The method of  claim 4 , wherein said quantity of said 17beta-estradiol is chosen such that the time of action of said 17beta-estradiol is substantially equal to said estimated healing time.  
     
     
         6 . The method of  claim 1 , wherein said supply of said 17beta-estradiol is effected by means of a drug elution system applied to said intravascular stent.  
     
     
         7 . Use of 17beta-estradiol as vessel healing substance after implantation of an intravascular stent.  
     
     
         8 . A method for producing an intravascular stent reducing complications after implantation into a vessel, comprising the steps of: 
 providing a stent body suitable for implantation; and    applying 17beta-estradiol to said stent body.    
     
     
         9 . The method of  claim 8 , wherein said stent body has a surface and said 17beta-estradiol is provided on said surface of said stent body.  
     
     
         10 . The method of  claim 9 , comprising the steps of: 
 providing a stent body defining an inner surface and an outer surface; and    providing 17beta-estradiol on said inner surface and/or said outer surface of said stent body.    
     
     
         11 . The method of  claim 10 , wherein said stent body is provided with an adhesive layer for said 17beta-estradiol on said inner surface and/or said outer surface.  
     
     
         12 . The method of  claim 11 , wherein said adhesive layer contains DLC (“diamond-like carbon”).  
     
     
         13 . The method of  claim 8 , wherein said 17beta-estradiol is applied to said surface of said stent body by means of a surface coating process.  
     
     
         14 . The method of  claim 13 , wherein said surface coating process is a CVD process (“chemical vapor deposition process”).  
     
     
         15 . The method of  claim 14 , comprising the steps of: 
 inserting said stent body to be coated with 17beta-estradiol together with said 17beta-estradiol into a vacuum chamber; and    vaporizing said 17beta-estradiol.    
     
     
         16 . The method of  claim 15 , wherein said vacuum chamber has a chamber wall, at least a part of said chamber wall being heated.  
     
     
         17 . The method of  claim 15 , wherein said stent body to be coated with 17beta-estradiol is cooled.  
     
     
         18 . The method of  claim 15 , wherein a plurality of stent bodies to be coated with 17beta-estradiol is provided in said vacuum chamber at the same time.  
     
     
         19 . The method of  claim 18 , wherein said stent bodies to be coated with 17beta-estradiol are cooled by means of common cooling means.  
     
     
         20 . The method of  claim 13 , wherein said stent body is coated with 17beta-estradiol to obtain a layer of 17beta-estradiol having a predetermined thickness.  
     
     
         21 . The method of  claim 20 , wherein said thickness of said layer of 17beta-estradiol is determined by means of layer thickness parameters.  
     
     
         22 . The method of  claim 21 , wherein one of said layer thickness parameters is the duration of said coating process.  
     
     
         23 . The method of  claim 8 , wherein a drug elution system is applied together with 17beta-estradiol to said stent body to be provided with 17beta-estradiol.  
     
     
         24 . An arrangement for coating one or more intravascular stents with a therapeutic coating substance, comprising: 
 a vacuum chamber having a chamber wall;    stent accommodation means for accommodating said stent or said stents in said vacuum chamber;    substance accommodation means for accommodating said coating substance in said vacuum chamber; and    vaporization means for vaporizing said coating substance in said vacuum chamber to achieve a coating process through which said one or more stents are coated with said coating substance.    
     
     
         25 . The arrangement of  claim 24 , further comprising heating means for heating at least a part of said chamber wall of said vacuum chamber.  
     
     
         26 . The arrangement of  claim 24 , further comprising cooling means for cooling said stent or said stents to be coated.  
     
     
         27 . The arrangement of  claim 24 , further comprising layer thickness determining means for determining a layer thickness of said coating substance on said stent or said stents.  
     
     
         28 . The arrangement of  claim 27 , wherein said layer thickness determining means comprise timer means arranged to determine the duration of said coating process.  
     
     
         29 . The arrangement of  claim 24 , wherein said coating substance contains 17beta-estradiol.  
     
     
         30 . The intravascular stent of  claim 29 , comprising: 
 a stent body having an inner surface and an outer surface; and    17beta-estradiol provided on said inner surface and/or said outer surface of said stent body.    
     
     
         31 . The intravascular stent of claim  30 , wherein said stent body is provided with an adhesive layer for said 17beta-estradiol on said inner surface and/or said outer surface.