Intravascular radially expandable stent

• US 5,443,496 A
• Filed: 10/15/1993
• Issued: 08/22/1995
• Est. Priority Date: 03/19/1992
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Schwartz, Robert S., Dror, Michael, Bresnahan, John, Bergman, Rebecca M., Coury, Arthur J., Hull, Vincent W., Lindell, Elaine
• Primary Examiner(s): Prebilic, Paul B.
• Application Number:
  US08/138,041
• Time in Patent Office: 676 Days
• Field of Search: 606/195, 606/198, 604/890.1, 623/1
• US Class Current: 623/1.16
• CPC Class Codes: A61F 2/0077 Special surfaces of prostheses, e.g. for improving ingrowth A61F2/30767 takes precedence
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/88 the wire-like elements formed as helical or spiral coils forming a net-like or mesh-like structure A61F2/90
• CPC Class Codes: A61F 2/958 Inflatable balloons for placing stents or stent-grafts
• CPC Class Codes: A61F 2002/825 having longitudinal struts
• CPC Class Codes: A61F 2240/001 Designing or manufacturing processes
• CPC Class Codes: A61F 2250/0067 Means for introducing or releasing pharmaceutical products into the body
• CPC Class Codes: Y10T 156/1026 with slitting or removal of material at reshaping area prior to reshaping
• CPC Class Codes: Y10T 29/49885 with coating before or during assembling
• CPC Class Codes: Y10T 29/49906 Metal deforming with nonmetallic bonding
• CPC Class Codes: Y10T 29/4994 Radially expanding internal tube
• CPC Class Codes: Y10T 29/49982 Coating
• CPC Class Codes: Y10T 29/49984 and casting
• CPC Class Codes: Y10T 29/49986 Subsequent to metal working

Abstract

A radially expandable stent for implantation within a body lumen having a generally cylindrical body with open proximal and distal ends, the cylindrical body comprising a plurality of metal elements joined to allow flexing of the cylindrical body along the longitudinal axis of the body whereby the stent can conform to a curved body lumen and a polymeric film extending between the metal elements of the stent. The stent provides a biocompatible polymeric surface to contact and support a body lumen and also a flexible structure to allow the stent to conform closely to bends in a body lumen. The stent is especially useful for repairing an injury to blood vessels caused during angioplasty procedures.

Claims

1. In a radially expandable stent for implantation within a body lumen, the stent having a generally cylindrical body with a longitudinal axis and open proximal and distal ends, the cylindrical body comprising a plurality of metal elements, the metal elements including means for expanding the cylindrical body from a first diameter to a second diameter and means for providing radial support for the body lumen at the expanded diameter, the metal elements joined together from the proximal to the distal end of the cylindrical body to allow flexing of the stent along the longitudinal axis to permit the stent to conform to a curved body lumen, the improvement comprising:

a bioabsorbable polymeric film extending between the metal elements of the stent, the polymeric film having strain relief means located between the elements.

6. The stent of claim 1 wherein the strain relief means comprises one or more cuts in the film between adjacent metal elements.

7. The stent of claim 6 wherein the strain relief means is provided by one or more folds in the film between adjacent metal elements.

8. The stent of claim 1 wherein the metal elements are provided in the form of individual windings joined in a helical configuration and the film extends between the windings.

9. The stent of claim 1 wherein the film is in the form of a sleeve wrapping around the outside of the cylindrical body of the stent.

10. The stent of claim 1 wherein the film has a thickness of less than about 0.005 inch.

11. The stent of claim 1 wherein the film also encloses the metal elements.

12. The stent of claim 1 wherein the film further comprises a therapeutic substance.

2. A radially expandable stent for implantation within a body lumen comprising:

(a) a generally cylindrical body with open proximal and distal ends, the cylindrical body comprised of a plurality of support elements, the support elements including means for expanding the cylindrical body from a first diameter to a second diameter and means for providing radial support for the body lumen at the expanded diameter, the support elements joined together from the proximal to the distal end of the cylindrical body;

(b) a polymeric film attached to the support elements of the cylindrical body and extending longitudinally between the support elements along the cylindrical body when the cylindrical body is expanded to the second diameter; and

(c) a therapeutic substance attached to at least one side of the film wherein the therapeutic substance is in microcapsules.

3. The stent of claim 2 wherein the microcapsules are incorporated into the film.

4. The stent of claim 2 wherein a second therapeutic substance is in microcapsules attached to the film.

5. The stent of claim 4 wherein the microcapsules are incorporated into the film.