Flexible stent

• US 7,316,710 B1
• Filed: 12/30/2002
• Issued: 01/08/2008
• Est. Priority Date: 12/30/2002
• Status: Active Grant

• Current Assignee: Advanced Cardiovascular Systems Incorporated
• Original Assignee: Advanced Cardiovascular Systems Incorporated
• Inventors: Cheng, E Tina, Prabhu, Santosh, Pienknagura, Carla Rosa, Ta, Diem Uyen, Krueger, Kyle Marie
• Primary Examiner(s): THALER, MICHAEL H
• Application Number:
  US10/334,033
• Time in Patent Office: 1,835 Days
• Field of Search: 623/1.15, 623/1.16, 623/1.17
• US Class Current: 623/1.15
• 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 2002/91525 within the whole structure different bands showing different meander characteristics, e.g. frequency or amplitude
• 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 2002/91575 connected peak to trough
• CPC Class Codes: A61F 2002/91583 by a bridge, whereby at least one of its ends is connected along the length of a strut between two consecutive apices within a band
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2230/0013 Horseshoe-shaped, e.g. crescent-shaped, C-shaped, U-shaped
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0029 differing in bending or flexure capacity
• CPC Class Codes: A61F 2250/0036 differing in thickness
• CPC Class Codes: A61F 2250/0067 Means for introducing or releasing pharmaceutical products into the body
• CPC Class Codes: A61F 2250/0068 the pharmaceutical product being in a reservoir
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61F 2310/00017 Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00023 Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00029 Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium
• CPC Class Codes: A61F 2310/00053 Vanadium or V-based alloys
• CPC Class Codes: A61F 2310/00107 Palladium or Pd-based alloys
• CPC Class Codes: A61F 2310/00131 : Tantalum or Ta-based alloys
• CPC Class Codes: A61F 2310/00137 : Tungsten or W-based alloys
• CPC Class Codes: A61F 2310/00143 : Iridium or Ir-based alloys
• CPC Class Codes: A61F 2310/00149 : Platinum or Pt-based alloys
• CPC Class Codes: A61F 2310/00155 : Gold or Au-based alloys

Abstract

The present invention is directed to a flexible expandable stent for implantation in a body lumen, such as a coronary artery. The stent generally includes a series of metallic cylindrical rings longitudinally aligned on a common axis of the stent and interconnected by a series of links which be polymeric or metallic. Varying configurations and patterns of the links and rings provides longitudinal and flexural flexibility to the stent while maintaining sufficient column strength to space the cylindrical rings along the longitudinal axis and providing a low crimp profile, enhanced stent security and radial stiffness.

Claims

1. An intravascular stent while in an unexpanded state, comprising:

a distal section, a proximal section, and a center section there between;

the distal section and the proximal section each having a single cylindrical ring and the center section having a plurality of cylindrical rings;

the cylindrical ring of the distal section and the cylindrical rings of the center section having U-shaped undulations with peaks and valleys, wherein each peak is connected to a valley by a first segment that extends along most of the distance between such peak and valley; and

the cylindrical ring in the proximal section having U-shaped undulations with peaks and valleys, wherein each peak is connected to a valley by a second segment that extends along most of the distance between such peak and valley;

wherein said first segments have a shape that is different than the shape of said second segments as each of said first segments defines a substantially straight line while each of said second segments defines a series of curves.

2. The stent of claim 1, wherein adjacent cylindrical rings are connected by links.

3. The stent of claim 2, wherein two links connect the cylindrical ring in the distal section to an adjacent cylindrical ring in the center section.

4. The stent of claim 2, wherein two links connect the cylindrical ring in the proximal section to an adjacent cylindrical ring in the center section.

5. The stent of claim 2, wherein three links connect adjacent cylindrical rings in the center section.

6. The stent of claim 2, wherein the cylindrical rings and the links are formed from a metallic material taken from the group of metals consisting of stainless steel, titanium, tungsten, tantalum, vanadium, nickel-titanium, cobalt-chromium, gold, palladium, platinum and platinum-iridium.

7. The stent of claim 2, wherein at least a portion of the stent is coated with a therapeutic drug.

8. The stent of claim 7, wherein at least one of the links includes micro depots for receiving the therapeutic drug.

9. The stent of claim 7, wherein at least one of the links includes micro channels for receiving the therapeutic drug.

10. The stent of claim 7, wherein at least one ring other than a center ring includes micro depots for receiving the therapeutic drug.

11. The stent of claim 7, wherein at least one ring other than a center ring includes micro channels for receiving the therapeutic drug.