Stent delivery system and method of manufacturing same

• US 6,699,274 B2
• Filed: 01/22/2001
• Issued: 03/02/2004
• Est. Priority Date: 01/22/2001
• Status: Expired due to Term

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Scimed Life Systems Incorporated (Boston Scientific Corporation)
• Inventors: Stinson, Jonathan S.
• Primary Examiner(s): McDermott, Corrine
• Assistant Examiner(s): SWEET, THOMAS
• Application Number:
  US09/767,212
• Publication Number:
  US 20020099435A1
• Time in Patent Office: 1,135 Days
• Field of Search: 625/1.11, 625/1.12, 625/1.2, 623/1.11, 623/1.12, 608/108, 606/108
• US Class Current: 623/1.12
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/92 Stents in the form of a rolled-up sheet expanding after insertion into the vessel , e.g. with a spiral shape in cross-section
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2/966 with relative longitudinal movement between outer sleeve and prosthesis, e.g. using a push rod
• CPC Class Codes: A61F 2/97 the outer sleeve being splittable
• CPC Class Codes: A61F 2002/9665 with additional retaining means
• CPC Class Codes: A61F 2220/005 using adhesives
• CPC Class Codes: A61F 2220/0058 soldered or brazed or welded
• CPC Class Codes: Y10T 29/4984 Retaining clearance for motion between assembled parts
• CPC Class Codes: Y10T 29/49908 Joining by deforming
• CPC Class Codes: Y10T 29/49913 by constricting outer annulus
• CPC Class Codes: Y10T 29/49929 Joined to rod
• CPC Class Codes: Y10T 29/49966 with supplemental joining

Abstract

Stent delivery system and method of manufacturing same. In one embodiment, the stent delivery system comprises an inner catheter. A handle is disposed at the proximal end of the inner catheter, and an enlarged tip is disposed at the distal end thereof. A stent engaging sleeve coaxially surrounds and is secured to a portion of the inner catheter proximally contiguous to the tip. The stent engaging sleeve is used to frictionally engage a stent mounted thereover in such a way as to prevent the stent, during deployment, from sliding proximally relative to the inner catheter. The system additionally comprises a self-expandable stent of the type comprising a knitted mesh of nitinol wire flexible in both the radial and longitudinal axes. The stent is mounted over the stent engaging sleeve in a longitudinally stretched state and is maintained, until deployment, in the stretched state by a stent restraining sleeve. The stent restraining sleeve, which coaxially surrounds the stent and is appropriately sized to maintain the stent in its stretched state, is a braided tube formed directly over the stent. The system also includes an outer catheter that surrounds much of the distal end of the inner catheter up to its tip, the outer catheter being adapted for axial movement relative to the inner catheter. The distal end of the outer catheter, which is mechanically coupled to the distal end of the stent for axial movement, is provided with an increased inner diameter to accommodate those components positioned between the inner and outer catheters. To facilitate the advancement of the outer catheter over the stent restraining sleeve during the assembly of the system, the outer catheter is fabricated with a longitudinal split extending proximally from its distal end. After the outer catheter has been positioned over the stent restraining sleeve, the split is sealed.

Claims

1. A stent delivery system comprising:

(a) an inner catheter;

(b) an outer catheter, said outer catheter surrounding at least a portion of the length of said inner catheter and adapted for axial movement relative to said inner catheter;

(c) a self-expandable stent disposed between said inner catheter and said outer catheter; and

(d) a stent restraining member disposed between said outer catheter and said self-expandable stent and adapted for sliding movement relative to said inner catheter, said stent restraining member being a cylindrical sleeve surrounding said self-expandable stent and dimensioned to maintain said self-expandable stent in a compressed state.

2. The stent delivery system as claimed in claim 1 wherein said stent restraining member is mechanically coupled to said outer catheter for axial movement.

3. The stent delivery system as claimed in claim 1 wherein said self-expandable stent is a knitted mesh of a nickel-titanium memory alloy wire flexible in both the radial and longitudinal axes.

4. The stent delivery system as claimed in claim 1 further comprising means for deterring said self-expandable stent from sliding proximally relative to said inner catheter during deployment.

5. The stent delivery system as claimed in claim 4 wherein said deterring means comprises a stent engaging sleeve fixed to said inner catheter, said stent engaging sleeve being provided with projections on its outer surface adapted to engage said self-expandable stent in such a way as to deter said self-expanding stent from sliding proximally relative thereto.

6. The stent delivery system as claimed in claim 1 further comprising a stent engaging sleeve fixed to said inner catheter, said self-expandable stent surrounding said stent engaging sleeve, said stent engaging sleeve having an outer surface adapted to engage said self-expandable stent in such a way as to deter said self-expandable stent from sliding proximally relative thereto.

7. The stent delivery system as claimed in claim 1 further comprising a sleeve holding member, said sleeve holding member being fixed to said inner catheter and being secured to the proximal end of said stent restraining member.

8. A stent delivery system comprising:

(a) an inner catheter;

(b) an outer catheter, said outer catheter surrounding at least a portion of the length of said inner catheter and adapted for axial movement relative to said inner catheter;

(c) a self-expandable stent disposed between said inner catheter and said outer catheter; and

(d) a stent restraining member disposed between said outer catheter and said self-expandable stent, said stent restraining member being dimensioned to maintain said self-expandable stent in a compressed state, wherein said stent restraining member is a braided tube surrounding said self-expandable stent.

10. The stent delivery system as claimed in claim 8 wherein said braided tube is from a fine polyester filamentary material that is strong, flexible and has a low coefficient of friction.

11. The stent delivery system as claimed in claim 8 wherein said braided tube is made from a fine metal wire that is strong, flexible and has a low coefficient of friction.

9. The stent delivery system as claimed in clam 8 wherein said braided tube is made from a strong, flexible, filamentary material having a low coefficient of friction.

12. A stent delivery system comprising:

(a) an inner catheter;

(b) an outer catheter, said outer catheter surrounding at least a portion of the length of said inner catheter and adapted for axial movement relative to said inner catheter;

(c) a self-expandable stent disposed between said inner catheter and said outer catheter, wherein said self-expandable stent is a knitted mesh of a nickel-titanium memory alloy wire flexible in both the radial and longitudinal axes;

(d) a stent restraining member disposed between said outer catheter and said self-expandable stent, said stent restraining member being dimensioned to maintain said self-expandable stent in a compressed state, wherein said stent restraining member is a braided tube surrounding said self-expandable stent and wherein said braided tube is mechanically coupled to said outer catheter for axial movement; and

(e) a stent engaging sleeve fixed to said inner catheter, said self-expandable stent surrounding said stent engaging sleeve, said stent engaging sleeve having an outer surface adapted to engage said self-expandable stent in such a way as to deter said self-expandable stent from sliding proximally relative thereto.