Flexible stent with torque-absorbing connectors

• US 20080294240A1
• Filed: 10/09/2007
• Published: 11/27/2008
• Est. Priority Date: 05/23/2007
• Status: Active Grant

• Current Assignee: Abbott Laboratories Vascular Enterprises Limited (Abbott Laboratories)
• Original Assignee: Abbott Laboratories Vascular Enterprises Limited (Abbott Laboratories)
• Inventors: Casey, Brendan J.
• Granted Patent: US 8,128,679 B2
• Time in Patent Office: Days
• US Class Current: 623/1.16
• 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 2/89 the wire-like elements comprising two or more adjacent rings flexibly connected by separate members
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2002/91541 Adjacent bands are arranged out of phase
• CPC Class Codes: A61F 2002/91558 connected peak to peak
• CPC Class Codes: A61F 2230/0069 cylindrical
• CPC Class Codes: A61F 2250/0031 made from both resorbable and non-resorbable prosthetic parts, e.g. adjacent parts

Abstract

The present invention concerns a stent with a highly flexible structure that is configured to provide an elevated degree of vessel scaffolding and to absorb torque applied on the stent. In one embodiment, the stent of the present invention includes an essentially tubular body formed by a web structure that is composed of a plurality of longitudinally adjacent web rings, each including a plurality of web elements that are disposed circumferentially around the longitudinal axis of the stent and that are adjoined one to the other by a junction bend. Each junction bend in a first web ring is coupled to another junction bend in a neighboring ring by a connector having a step-wise configuration, in which a central segment of the connector is disposed essentially parallel to the longitudinal axis of the stent and may become twisted to absorb torque imposed on the stent.

Claims

1. A stent comprising:

a web structure defining an essentially tubular body expandable from a contracted delivery configuration to an expanded deployed configuration;

a plurality of longitudinally adjacent web rings defining the web structure; and

a plurality of sequentially adjoined web elements defining the web rings, the web elements being disposed substantially parallel to a longitudinal axis of the essentially tubular body when in the contracted delivery configuration, pairs of the web elements being sequentially adjoined at junction bends,

wherein a first junction bend in a first web ring is connected to a second junction bend in a neighboring web ring by a connector having a plurality of segments disposed one in relation to the other in step-wise configuration,

wherein at least one of the plurality of segments in a central position within the connector is disposed in a direction essentially parallel to the longitudinal axis of the essentially tubular body, and

wherein two junction bends connected by the connector are laterally offset one in relation to the other.

2. The stent of claim 1, wherein each of the web elements comprises a central member having a first and a second ends, wherein the central member is disposed essentially parallel to the longitudinal axis in the contracted delivery configuration, wherein the central member is connected at the first end to a first end member at a first obtuse angle, and wherein the central member is connected at the second end to a second end member at a second obtuse angle.

3. The stent of claim 2, wherein the first and the second obtuse angles are essentially equal.

4. The stent of claim 2, wherein the web elements of each web ring are nested one into the other in the contracted delivery configuration, and wherein the junction bends have an arcuate shape.

5. The stent of claim 2, wherein the web elements in the first web ring are oriented at approximately 180 degrees in relation to the web elements in the neighboring web ring.

6. The stent of claim 1, wherein the connector comprises three sequentially connected segments, wherein the first and the third segments are disposed essentially parallel to each other, wherein the second segment connects the first and the thirst segments, and wherein the second segment is disposed essentially parallel to a longitudinal axis of the essentially tubular body.

7. The stent of claim 6, wherein the first and the second segments, and the second and the third segments, are disposed one with respect to the other at angles between 100 and 170 degrees.

8. The stent of claim 6, wherein the second segment has a helical curvature.

9. The stent of claim 6, wherein the second segment is configured to become twisted upon application of a radial force on the essentially tubular body.

10. The stent of claim 6, wherein the first and third segments translate one in relation to the other upon application of a bending force on the essentially tubular body.

11. The stent of claim 6, wherein the second segment has a cross-sectional area different from the cross-sectional area of the first and third segments.

12. The stent of claim 1, wherein each junction bend in the first web ring is connected to one junction bend in one neighboring web ring by one connector.

13. The stent of claim 1, wherein the second element is coupled to the first and the second elements by connecting area having radial axes one not parallel to the other.

14. The stent of claim 1, wherein the connector is manufactured from a biodegradable material.

15. The stent of claim 1, wherein the web structure is configured to self-expand from the contracted delivery configuration to the expanded deployed configuration.

16. The stent of claim 1, wherein the web structure is configured to expand from the contracted delivery configuration to the expanded deployed configuration by application of a radial pressure to an interior surface of the essentially tubular body.

17. The stent of claim 1, further comprising a coating disposed on the web structure, the coating comprising a bioactive agent.

18. A method of stenting a bodily vessel comprising:

providing a stent having a web structure defining an essentially tubular body expandable from a contracted delivery configuration to an expanded deployed configuration, a plurality of longitudinally adjacent web rings defining the web structure, and a plurality of sequentially adjoined web elements defining the web rings, the web elements being disposed substantially parallel to a longitudinal axis of the essentially tubular body in the contracted delivery configuration, pairs of the web elements being sequentially adjoined at a junction bend, a first junction bend in a first web ring being connected to a second junction bend in a neighboring web ring by a connector having a plurality of segments disposed one in relation to the other in step-wise configuration, at least one of the plurality of segments being disposed in a direction essentially parallel to the longitudinal axis of the essentially tubular body, two junction bends connected by the connector being laterally offset one in relation to the other;

disposing the stent in the contracted delivery configuration in the bodily vessel; and

causing an expansion of the stent from the contracted delivery configuration to the expanded deployed configuration, the connector absorbing at least some of a torque applied on the stent by the expansion.

19. The method of claim 18, wherein providing the stent comprises providing the connector with three sequentially connected segments, the first and the third segments being disposed essentially parallel to each other, the second segment connecting the first and the third segments, the second segment being disposed essentially parallel to a longitudinal axis of the essentially tubular body.

20. The method of claim 19, wherein providing the connector comprises providing the first and the second segments, and the second and the third segments, disposed one with respect to the other at angles between 45 and 135 degrees.

21. The method of claim 19, wherein providing the connector providing the second segment with a helical curvature.

22. The method of claim 19, wherein providing the connector comprises providing the second segment configured to be twisted upon application of a radial force on the essentially tubular body.

23. The method of claim 19, wherein providing the connector comprises providing the first and third segments configured to translate one in relation to the other upon application of a bending force on the essentially tubular body.

24. The method of claim 19, wherein providing the connector comprises providing the second segment with a cross-sectional area different from the cross-sectional area of the first and third segments.