Flexible stent

• US 6,740,114 B2
• Filed: 03/02/2001
• Issued: 05/25/2004
• Est. Priority Date: 03/01/2001
• Status: Expired due to Term

• Current Assignee: Cardinal Health Switzerland 515 GmbH (Cardinal Health, Inc.)
• Original Assignee: Cordis Corporation (Cardinal Health, Inc.)
• Inventors: Burgermeister, Robert
• Primary Examiner(s): McDermott, Corrine
• Assistant Examiner(s): Stewart, Alvin
• Application Number:
  US09/797,641
• Publication Number:
  US 20020123799A1
• Time in Patent Office: 1,180 Days
• Field of Search: 623/1.1, 623/1.11, 623/1.12, 623/1.15, 623/1.17
• US Class Current: 623/1.17
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2002/91508 the meander having a difference in amplitude along the band
• CPC Class Codes: A61F 2002/91516 the meander having a change in frequency along the band
• CPC Class Codes: A61F 2002/91525 within the whole structure different bands showing different meander characteristics, e.g. frequency or amplitude
• CPC Class Codes: A61F 2002/91533 characterised by the phase between adjacent bands
• CPC Class Codes: A61F 2002/91558 connected peak to peak
• CPC Class Codes: A61F 2002/91566 connected trough to trough
• CPC Class Codes: A61F 2002/91575 connected peak to trough
• CPC Class Codes: A61F 2230/0054 V-shaped

Abstract

A preferred embodiment of a stent provides a folded strut section that provides both structural rigidity and reduction in foreshortening of the stent mechanism. A flexible section provides flexibility for delivery of the stent mechanism. In a second embodiment, flexible section columns are angled with respect to each other, and to the longitudinal axis of the stent. These relatively flexible sections are oppositely phased in order to negate any torsion along their length. In yet another embodiment, the flexible connector can take on an undulating shape (like an “N”), but such that the longitudinal axis of the connector is not parallel with the longitudinal axis of the stent. Finally, a new method is disclosed for making stents. The method consists of performing a standard photochemical machining process of cutting, cleaning and coating the tube with a photoresist. However, unlike former methods, the photoresist image is developed on the surface of the cylindrical metallic tube, which results in a controlled variable etching rate at selected sites on the cylindrical metallic tube during the etching process. Further embodiments provide living hinge connectors and connections along the length of the radial strut member.

Claims

1. A stent having a generally tubular shape and a longitudinal axis, comprising:

a plurality of columnar sections and a plurality of flexible sections, each of said sections arranged circumferentially around said generally tubular shape, and a said columnar section attached to at least one flexible section, and said columnar section and flexible section each having predetermined longitudinal lengths, and wherein said columnar sections and said flexible sections each maintain their respective longitudinal lengths during expansion of the stent from a first unexpanded configuration to a second expanded configuration.

2. The stent of claim 1 wherein consecutive flexible sections are out of phase with one another.

3. The stent of claim 1 wherein the flexible sections have an axis that is non-parallel to the longitudinal axis of the stent.

4. The stent of claim 3 wherein consecutive flexible sections are out of phase with one another.

5. The stent of claim 3 wherein the flexible sections are connected to columnar sections by means of connector members, said connector members placed out of phase with one another.

6. The stent of claim 1 wherein the flexible sections have an axis parallel to the longitudinal axis of the stent.

7. The stent of claim 6 wherein consecutive flexible sections are out of phase with one another.

8. The stent of claim 6 wherein the flexible sections are connected to columnar sections by connector members, said connector members placed out of phase with one another.

9. The stent of claim 1 wherein the flexible sections are connected to columnar sections by connector members, said connector members placed out of phase with one another.