Stent with reinforced struts and bimodal deployment

• US 6,773,455 B2
• Filed: 05/03/2001
• Issued: 08/10/2004
• Est. Priority Date: 06/24/1997
• Status: Expired due to Term

• Current Assignee: Advanced Cardiovascular Systems Incorporated (Abbott Laboratories)
• Original Assignee: Advanced Cardiovascular Systems Incorporated (Abbott Laboratories)
• Inventors: Allen, Richard T., Cox, Daniel L.
• Primary Examiner(s): McDermott, Corrine
• Assistant Examiner(s): Matthews, William H.
• Application Number:
  US09/848,819
• Publication Number:
  US 20010016770A1
• Time in Patent Office: 1,195 Days
• Field of Search: 623/1.1, 623/1.11, 623/1.12, 623/1.13, 623/1.15, 623/1.16
• 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 2002/91508 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 2002/91533 characterised by the phase between adjacent bands
• CPC Class Codes: A61F 2002/91575 connected peak to trough
• CPC Class Codes: A61F 2230/0013 Horseshoe-shaped, e.g. crescent-shaped, C-shaped, U-shaped

Abstract

The invention is directed to an expandable stent for implantation in a body lumen, such as a coronary artery or peripheral vein. The stent consists of a plurality of radially expandable cylindrical elements generally aligned on a common longitudinal stent axis and interconnected by one or more interconnecting members placed so as to limit longitudinal contraction during radial expansion. The individual radially expandable cylindrical elements are formed in a serpentine pattern having bends alternating in peaks and valleys designed to expand evenly under radial stress, and to maximize the overall radial expansion ratio. Each peak and valley includes reinforcing members that extend across and proximate to each bend. Sizing and construction of the struts forming the peaks and valleys can create bimodal deployment wherein the struts bend under increasing stresses to enable the stent to expand to larger diameters.

Claims

1. A flexible stent for implantation in a body lumen and expandable from a contracted condition to an expanded condition, comprising:

a plurality of adjacent cylindrical elements which are expandable in the radial direction and arranged in alignment along a longitudinal stent axis;

the cylindrical elements formed in a serpentine wave pattern transverse to the longimdinal axis and containing a plurality of alternating peaks and valleys;

at least one interconnecting member extending between adjacent cylindrical elements and connecting them to one another;

at least one reinforcing member extending across a width of the alternating peaks and valleys such that the reinforcing member is curved and has a circumferential width when the stent is in the contracted condition;

each reinforcing member lying in the same circumferential plane as the cylindrical elements and having a configuration essentially parallel to the longitudinal stent axis when the stent is in the contracted condition; and

the serpentine pattern having varying degrees of curvature in regions of the peaks and valleys adapted so that radial expansion of the adjacent cylindrical elements is substantially uniform around a circumference of the cylindrical elements during expansion of the stent from the contracted condition to the expanded condition;

wherein the circumferential width of each reinforcing member is smaller than the width of the peak or valley it extends across;

wherein each of the alternating peaks and valleys has one of said reinforcing members extending across its width.

2. A flexible stent for implantation in a body lumen and expandable from a contracted condition to an expanded condition, comprising:

a plurality of adjacent cylindrical elements which are expandable in the radial direction and arranged in alignment along a longitudinal stent axis;

the cylindrical elements formed in a serpentine wave pattern transverse to the longitudinal axis and containing a plurality of alternating peaks and valleys;

at least one interconnecting member extending between adjacent cylindrical elements and connecting them to one another;

at least one reinforcing member extending across a width of the alternating peaks and valleys such that the reinforcing member is curved and has circumferential width when the stent is in the contracted condition;

each reinforcing member lying in the same circumferential plane as the cylindrical elements and having a configuration essentially parrallel to the longitudinal stent axis when the stent is in the contracted condition; and

the serpentine patter having varying degrees of curvature in regions of the peaks and valleys adapted so that radial expansion of the adjacent cylindrical elements is substantially uniform around a circumference of the cylindrical elements during expansion of the stent from the contracted condition to the expanded condition;

wherein the circumferential width of each reinforcing member is smaller than the width of the peak or valley it extends across;

wherein the interconnecting member connects a reinforcing member of a valley of one cylindrical element with a valley of an adjacent cylindrical element.

3. A flexible stent for implantation in a body lumen and expandable from a contracted condition to an expanded condition, comprising:

a plurality of adjacent cylindrical elements which are expandable in the radial direction and arranged in alignment along a longitudinal stent axis;

the cylindrical elements formed in a serpentine wave pattern transverse to the longitudinal axis and containing a plurality of alternating peaks and valleys;

at least one interconnecting member extending between adjacent cylindrical elements and connecting them to one another;

at least one reinforcing member extending across a width of the alternating peaks and valleys such that the reinforcing member is curved and has a circumferential width when the stent is in the contracted condition;

each reinforcing in member lying in the same circumferential plane as the cylindrical elements and having a configuration essentially parallel to the longitudinal stent axis when the stent is in the contracted condition; and

the serpentine pattern having varying degrees of curvature in regions of the peaks and valleys adapted so that radial expansion of the adjacent cylindrical elements is substantially uniform around a circumference of the cylindrical elements during expansion of the stent from the contracted condition to the expanded condition;

wherein the circumferential width of each reinforcing member is smaller than the width of the peak or valley it extend across;

wherein the reinforcing member is comprised of a first quarter turn that transitions into a half turn, which transitions into a second quarter turn.