Radiopaque super-elastic intravascular stent

• US 8,623,071 B2
• Filed: 01/07/2008
• Issued: 01/07/2014
• Est. Priority Date: 01/07/2008
• Status: Expired due to Fees

• Current Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Original Assignee: DePuy Synthes Products LLC (Johnson & Johnson)
• Inventors: Lundkvist, Andre S., Watson, David A.
• Primary Examiner(s): Isabella, David
• Assistant Examiner(s): Sharma, Yashita
• Application Number:
  US11/970,338
• Publication Number:
  US 20090177268A1
• Time in Patent Office: 2,192 Days
• Field of Search: 623/1.22, 623/1.35, 623/1.15, 623/1.18, 623/1.2, 623/1.33, 623/1.42, 623/1.44, 623/1.46
• US Class Current: 623/1.22
• CPC Class Codes: A61B 17/12118 for positioning in conjunction with a stent
• CPC Class Codes: A61B 2017/00526 Methods of manufacturing
• CPC Class Codes: A61F 2/86 Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2210/0076 multilayered, e.g. laminated structures
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2240/001 Designing or manufacturing processes
• CPC Class Codes: A61F 2250/0039 differing in diameter
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: B23P 13/00 Making metal objects by operations essentially involving machining but not covered by a single other subclass making specific objects B23P15/00
• CPC Class Codes: Y10T 29/4998 Combined manufacture including applying or shaping of fluent material

Abstract

The intravascular stent is formed from a composite wire includes an inner core of radiopaque metal, a polymer layer coaxially disposed about the inner core, and an outer metal layer coaxially disposed about the polymer layer. The intermediary polymer layer acts as a barrier material between the inner core and the outer sheath, so that the inner core and outer sheath may be made of dissimilar metallic layers, and the intermediary polymer layer will prevent a galvanic reaction between the inner core and the peripheral metal layer. The intravascular stent has ends flared radially outwardly to prevent radially and longitudinally inward deformation of the ends of the stent when the stent is disposed in a desired location in a patient'"'"'s vasculature.

Claims

1. A generally tubular intravascular stent having opposing first and second ends, said intravascular stent comprising:

a plurality of end loop portions at the opposing first and second ends of the stent, and an intermediate tubular body portion formed of a plurality of intermediate circumferential loops between the plurality of end loop portions, said intermediate tubular body portion having a first diameter, an enlarged first end and an enlarged opposing second end, said enlarged first and second ends having a second diameter greater than the first diameter of the intermediate tubular body portion, and said plurality of end loop portions flaring radially outward at an angle of 30°

with respect to a longitudinal axis of the intermediate tubular body portion of the stent, wherein said plurality of end loop portions and said plurality of intermediate circumferential loops of said intermediate tubular body portion are formed from a single spirally wound composite wire including an elongated inner core having a selected length and formed from a radiopaque metal, an outer metal layer coaxially disposed around said elongated inner core along the length of said elongated inner core, wherein said outer metal layer is formed of a nickel-titanium alloy, and wherein said elongated inner core and said outer metal layer are made of dissimilar metals, and a continuous intermediate polymer layer disposed between said outer metal layer and said elongated inner core, said continuous intermediate polymer layer being configured to insulate said elongated inner core and said outer metal layer from galvanic corrosion and prevent current flow between said elongated inner core and said outer metal layer, and said continuous intermediate polymer layer being formed from a polymer selected from the group consisting of poly-para-xylylene, a fluorine substituted poly-para-xylylene, and combinations thereof, wherein said intravascular stent takes on a linear shape when stretched, without the ends shrinking to a diameter less than the diameter of the central body of the stent when disposed in a desired location in a patient'"'"'s vasculature, said composite wire having a first free end and a second free end placed in close proximity to each other in the intermediate tubular body portion, and a short segment of heat shrink tubing capturing said first and second free ends together forming a connection of the first and second free ends of the composite wire in the intermediate tubular body portion, said connection forming a continuation of one of said plurality of intermediate circumferential loops, to thereby prevent the free ends of the composite wire from extending away from the body of the stent.

2. The intravascular stent of claim 1, wherein the radiopaque metal is selected from the group consisting of platinum, tantalum, gold, and combinations thereof.

3. The intravascular stent of claim 1 wherein the inner core is cylindrical.

4. The intravascular stent of claim 1, wherein the inner core is disposed centrally along a longitudinal axis of the composite wire.

5. The composite wire of claim 1, wherein the outer metal layer is formed of a superelastic alloy.

6. The intravascular stent of claim 1, wherein the outer metal layer is formed of nitinol.

7. The intravascular stent of claim 1, wherein the composite wire is formed as a cylindrical wire.