Integral vascular filter system with core wire activation

Abstract

A integral vascular filter system comprising a multi-filament guidewire and an integral filter which may be used to capture embolic particulates during medical procedures, while allowing for continuous perfusion of blood. Filter activation is achieved via the use of a central core wire. The vascular filter system addresses the clinical problem of minimizing profile or diameter, so as to enable or facilitate the crossing of a lesion or obstruction in the vessel.

That which is claimed is:  
     
         1 . A vascular filter system for insertion into a lumen of a vessel, said vascular filter system comprising: 
 a) a multi-filament guidewire having an outer diameter and an inner diameter, a distal end and a proximal end, a distal portion and a proximal portion;    b) a prescribed filter shape in said distal portion of said guidewire, said prescribed filter shape comprising said multi-filaments of said distal portion of said guidewire; said prescribed filter shape having a proximal end, a midpoint and a distal end, a smaller first diameter for insertion into said lumen of said vessel, and a larger second diameter for expanding to substantially equal the diameter of said lumen and to be placed in generally sealing relationship with said lumen;    c) a porous covering having a distal end and a proximal end, with said distal end of said porous covering attached near said distal end of said prescribed filter shape, and said proximal end of said porous covering attached near said midpoint of said prescribed filter shape, and;    d) a generally solid actuating core wire for causing said prescribed filter shape to move between said smaller first diameter, and said larger second diameter, said core wire having a proximal end and a distal end, wherein said distal end of said prescribed filter shape is attached near said distal end of said core wire, and said guidewire is coaxially disposed around said core wire.    
     
     
         2 . The vascular filter system according to  claim 1 , wherein said guidewire is made from Nickel-titanium alloy.  
     
     
         3 . The vascular filter system according to  claim 1 , wherein said guidewire is made from stainless steel alloy.  
     
     
         4 . The vascular filter system according to  claim 1 , wherein said prescribed filter shape achieves said smaller first diameter when said core wire is pushed distally to prevent said multi-filament wires from achieving said prescribed filter shape, and wherein said prescribed filter shape achieves said second larger diameter when said core wire is pulled proximally to allow said multi-filament wires to achieve said prescribed filter shape.  
     
     
         5 . The vascular filter system according to  claim 1 , wherein said guidewire is a twisted multi-filament guidewire.  
     
     
         6 . The vascular filter system according to  claim 1 , wherein a pore size of said porous covering is from about 20 to about 300 microns.  
     
     
         7 . The vascular filter system according to  claim 1 , wherein said porous covering comprises regularly-spaced laser-formed pores.  
     
     
         8 . The vascular filter system, according to  claim 1 , wherein said porous covering is a flexible polymeric material.  
     
     
         9 . The vascular filter system according to  claim 8 , wherein said flexible polymeric material is chosen from a group consisting of polyurethane, polyethylene, silicone, nylon, polypropylene, PVC, or a co-polymer or mixture thereof.  
     
     
         10 . The vascular filter system according to  claim 8 , wherein said flexible polymeric material is an elastomeric material capable of stretching to achieve said larger second diameter of said filter.  
     
     
         11 . The vascular filter system according to  claim 1 , wherein said porous covering is a flexible metallic material.  
     
     
         12 . The vascular filter system according to  claim 11 , wherein said flexible metallic material is a thin film Nickel Titanium material.  
     
     
         13 . A method for capturing embolic particulates within the lumen of a vessel during a medical procedure, while allowing for continuous perfusion of blood, comprising the steps of: 
 a) providing a multi-filament guidewire having an outer diameter and an inner diameter, a distal portion and a proximal portion, with a prescribed filter shape in said distal portion of said guidewire; said prescribed filter shape comprising said multi-filaments of said distal portion of said guidewire, said prescribed filter shape having a proximal end, a midpoint and a distal end, a smaller first diameter for insertion into a vessel, and a second larger diameter for expanding to substantially equal the diameter of said lumen and to be placed in generally sealing relationship with said lumen; a porous covering having a distal end and a proximal end, with said distal end of said porous covering attached near said distal end of said prescribed filter shape, and said proximal end of said porous covering attached near said midpoint of said prescribed filter shape; and a generally solid actuating core wire for causing said prescribed filter shape to move between said smaller first diameter, and said larger second diameter; 
 said core wire having a proximal end and a distal end, wherein said distal end of said prescribed filter shape is attached near said distal end of said core wire, and said guidewire is coaxially disposed around said core wire;  
   b) inserting said guidewire into said lumen of said vessel until said distal portion of said guidewire is positioned past an occlusion in said vessel;    c) retracting said actuating core wire to cause said distal portion of said guidewire to achieve said larger second diameter and said prescribed shape;    d) advancing additional devices over said guidewire, and positioning said devices at the site of said occlusion in said vessel;    e) performing additional procedures to therapeutically treat said occlusion in said vessel;    f) capturing embolic particulates generated by said procedures, in said porous covering on said distal portion of said guidewire;    g) removing said additional devices from said guidewire;    h) advancing said actuating core wire to cause said distal portion of said guidewire to achieve said smaller first diameter; and    i) removing said guidewire from said lumen of said vessel, with said embolic particulates captured in said porous covering.    
     
     
         14 . For use with a guidewire-based vascular filter system, the improvement comprising: 
 a core wire coaxially disposed within said guidewire, wherein said core wire is placed in tension to deploy said vascular filter.    
     
     
         15 . A vascular filter system for insertion into a lumen of a vessel, said vascular filter system comprising: 
 (a) a multi-filament guidewire having an outer diameter and an inner diameter, a distal end and a proximal end;    (b) a prescribed filter shape near said distal end of said guidewire, said 
 prescribed filter shape comprising said multi-filaments of said guidewire; said  
 prescribed filter shape having a proximal end, and a distal end, a smaller first  
 diameter for insertion into said lumen of said vessel, and a larger second  
 diameter for expanding to substantially equal the diameter of said lumen and  
 to be placed in generally sealing relationship with said lumen;  
   (c) a porous covering attached near said distal end of said prescribed filter shape, and;    (d) a generally solid actuating core wire for causing said prescribed filter shape to 
 move between said smaller first diameter, and said larger second diameter,  
 wherein said guidewire is coaxially disposed around said core wire.  
   
     
     
         16 . The vascular filter system according to  claim 15 , wherein said guidewire is made 
 from Nickel-titanium alloy.    
     
     
         17 . The vascular filter system according to  claim 15 , wherein said guidewire is made 
 from stainless steel alloy.    
     
     
         18 . The vascular filter system according to  claim 15  wherein said prescribed filter shape achieves said smaller first diameter when said core wire is 
 pushed distally to prevent said multi-filament wires from achieving said prescribed  
 filter shape, and wherein said prescribed filter shape achieves said second larger diameter when said core wire is pulled proximally to allow said multi-filament wires to achieve said prescribed filter shape.  
 
     
     
         19 . The vascular filter system according to  claim 15 , wherein said guidewire is a twisted multi-filament guidewire.  
     
     
         20 . The vascular filter system according to  claim 15 , wherein a pore size of said porous 
 covering is from about 20 to about 300 microns.    
     
     
         21 . The vascular filter system according to  claim 15 , wherein said porous covering 
 comprises regularly-spaced laser-formed pores.    
     
     
         22 . The vascular filter system, according to  claim 15 , wherein said porous covering is a 
 flexible polymeric material.    
     
     
         23 . The vascular filter system according to  claim 22 , wherein said flexible polymeric 
 material is chosen from a group consisting of polyurethane, polyethylene, silicone,    nylon, polypropylene, PVC, or a co-polymer or mixture thereof.    
     
     
         24 . The vascular filter system according to  claim 22 , wherein said flexible polymeric 
 material is an elastomeric material capable of stretching to achieve said larger second diameter of said filter.    
     
     
         25 . The vascular filter system according to  claim 15 , wherein said porous covering is a flexible metallic material.  
     
     
         26 . The vascular filter system according to  claim 25 , wherein said flexible metallic material is a thin film Nickel Titanium material.