Conical stent

• US 20020032479A1
• Filed: 09/04/2001
• Published: 03/14/2002
• Est. Priority Date: 11/27/1995
• Status: Active Grant

• Current Assignee: Boston Scientific Corporation
• Original Assignee: Schneider AG
• Inventors: Gianotti, Marc, Hofmann, Eugen, Hankh, Susanne
• Granted Patent: US 6,533,810 B2
• Time in Patent Office: Days
• US Class Current: 623/1.16
• 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 2230/0067 conical
• CPC Class Codes: A61F 2250/0037 differing in height or in length
• CPC Class Codes: A61F 2250/0039 differing in diameter
• CPC Class Codes: D04C 1/06 Braid or lace serving particular purposes
• CPC Class Codes: D10B 2509/06 Vascular grafts; stents

Abstract

The stent comprises a flexible self-expandable braided tubular wall having a proximal segment having an outer diameter, and a distal segment having an outer diameter smaller than the outer diameter of the proximal segment. An intermediate segment is formed between proximal and distal segments, which forms a truncated cone of which the base is forming the proximal end of the intermediate segment and of which the top is forming the distal end of the intermediate segment. A covering layer is arranged within the tubular wall.

Claims

1. A stent for use in a body passageway, comprising a flexible self-expandable braided tubular wall, characterized in that the tubular wall comprises a first proximal segment having proximal and distal ends and a first outer diameter, a second distal segment having proximal and distal ends and a second outer diameter smaller than said first outer diameter, and a third intermediate segment having a proximal end connected to the distal end of the first segment and a distal end connected to the proximal end of the second segment.

2. A stent according to claim 1, wherein said first proximal and second distal segments are cylindrical.

3. A stent according to claim 1, wherein said third intermediate segment is a truncated cone having a base forming the proximal end of the third intermediate segment and a top forming the distal end of the third intermediate segment.

4. A stent according to claim 1, wherein said third intermediate segment is formed of a plurality of consecutive truncated cones connected to one another, each of said truncated cones having a taper oriented towards the distal end of the intermediate segment.

5. A stent according to claim 4, wherein at least two of said consecutive cones are separated by a cylindrical segment connected thereto.

6. A stent according to claim 1, further comprising a covering layer of elastic material surrounding said tubular wall.

7. A stent according to claim 1, further comprising a covering layer of elastic material arranged within said tubular wall.

8. A stent according to claim 6, wherein at least a proximal portion of the first proximal segment is not covered by the covering layer.

9. A stent according to claim 6, wherein a distal portion of the second distal segment is not covered by the covering layer.

10. A stent according to claim 1, wherein the proximal end of the first proximal segment is flared up.

11. A stent according to claim 1, wherein the distal end of the second distal segment is flared up.

12. A method for manufacturing a stent comprising:

(a) forming an elongated mandrel having a first proximal segment having proximal and distal ends and a first outer diameter, a second distal segment having proximal and distal ends and a second outer diameter smaller than said first outer diameter, and a third intermediate segment having a proximal end connected to the distal end of the first segment and a distal end connected to the proximal end of the second segment;

(b) forming an elongated tubular braid of spring steel having proximal and distal ends and an inner diameter greater than said first outer diameter of the first segment of the mandrel;

(c) engaging said tubular braid over said mandrel;

(d) heating the tubular braid over the mandrel; and

,

(e) pulling during said heating the proximal and distal ends of the tubular braid away from one another on the mandrel to closely radially contract the tubular braid over the segments of said mandrel.

13. A method for manufacturing a stent comprising:

(a) forming an elongated tubular mandrel having a first proximal hollow segment having proximal and distal ends and a first inner diameter, a second distal hollow segment having proximal and distal ends and a second inner diameter smaller than said first inner diameter, and a third intermediate hollow segment having a proximal end connected to the distal end of the first hollow segment and a distal end connected to the proximal end of the second hollow segment;

(b) forming an elongated tubular braid of spring steel having proximal and distal ends and an outer diameter greater than the first inner diameter of the first hollow segment of the tubular mandrel;

(c) pulling the proximal and distal ends of the elongated tubular braid away from one another to radially contract the tubular braid;

(d) engaging the contracted tubular braid into the tubular mandrel;

(e) releasing the pull on the ends of the tubular braid to radially expand it in the mandrel; and

,

(f) heating the tubular braid in the mandrel to closely radially expand the tubular braid against the segments of the tubular mandrel.