Stent with optimal strength and radiopacity characteristics

• US 8,454,677 B2
• Filed: 01/09/2008
• Issued: 06/04/2013
• Est. Priority Date: 09/22/2000
• Status: Expired due to Term

• Current Assignee: Cordis Corporation (Cardinal Health, Inc.)
• Original Assignee: Cordis Corporation (Cardinal Health, Inc.)
• Inventors: Fischell, Robert E., Fischell, David R., Burpee, Janet
• Primary Examiner(s): Sweet, Thomas J
• Assistant Examiner(s): Prone, Christopher D
• Application Number:
  US12/007,289
• Publication Number:
  US 20080109068A1
• Time in Patent Office: 1,973 Days
• Field of Search: 623/1.15, 623/1.11, 623/1.16, 623/1.35
• US Class Current: 623/1.15
• 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 2002/91583 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 2210/0076 multilayered, e.g. laminated structures
• CPC Class Codes: A61F 2230/0013 Horseshoe-shaped, e.g. crescent-shaped, C-shaped, U-shaped
• CPC Class Codes: A61F 2250/0032 differing in radiographic density
• CPC Class Codes: A61F 2250/0036 differing in thickness
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers

Abstract

A stent in the form of a thin-walled, multi-cellular tubular structure is provided. The tubular structure has a longitudinal axis and the stent includes a plurality of circumferential sets of strut members. Each set of the strut members is longitudinally displaced from each other and connected to each other by longitudinally extending links. Each set of the strut members forms a closed and cylindrical portion of the stent. Further, each set of the strut members includes a plurality of connected curve sections and diagonal sections. The sets of the strut members further include end sets of strut members located at each end of the stent and central sets of strut members located between the end sets of the strut members. The diagonal sections of the end sets of the strut members have a center portion and two ends.

Claims

1. A deployed stent in the form of a thin-walled, multi-cellular, tubular structure having a longitudinal axis, the stent comprising:

a multiplicity of circumferential sets of strut members, each set of strut members being longitudinally separated each from the other and each set of strut members forming a closed, ring-like cylindrical portion of the stent, each set of strut members consisting of a multiplicity of strut elements, each strut element consisting of one curved section having an arcuate contour joined at a junction point to one diagonal section with each junction point being an end point of each curved section;

a multiplicity of generally longitudinally disposed sets of flexible links with each set of flexible links connecting two of the multiplicity of circumferential sets of strut members, each set of flexible links consisting of a multiplicity of individual flexible links, each individual flexible link being a single undulating structure that extends generally in the longitudinal direction that is parallel to the stunts longitudinal axis and at least one flexible link being an N-contoured link, each of said flexible links being coupled to a respective strut member curved section on opposing ends of said flexible links; and

the sets of strut members and connecting flexible links together forming a multiplicity of closed perimeter cells, each of said closed cells formed by a pair of first and second ones of said N-contoured links, said first and second N-contoured links having a distal end connected to the curved section of a next succeeding strut member and a proximal end connected to the curved section of a next preceding strut member defining a dosed contour of each of said closed cells, at least half of all closed perimeter cells having an inside perimeter length greater than 9 mm.

2. The deployed stent of claim 1 wherein at least half of the closed perimeter cells having an inside area of less than 0.323 square millimeters at a designed limit of expansion for the stent.

3. The deployed stent of claim 1 wherein at least half of the closed perimeter cells have an inside metal perimeter length that is less than 11 mm.

4. A stent in the form of a thin-walled, multi-cellular, tubular structure having a longitudinal axis, the stent comprising:

a multiplicity of circumferential sets of strut members, each set of strut members being longitudinally separated each from the other and each set of strut members forming a closed, ring-like cylindrical portion of the stent, each set of strut members consisting of a multiplicity of strut elements, each strut element consisting of one curved section having an arcuate contour joined at a junction point to one diagonal section in a continuous manner; and

a multiplicity of sets of flexible links with each set of flexible links connecting two of the multiplicity of sets of strut members, each set of flexible links consisting of a multiplicity of individual flexible links, each individual flexible link being a single undulating structure that extends generally in the longitudinal direction that is parallel to the stents longitudinal axis and each individual flexible link having two ends that are fixedly attached to an adjacent set of strut members;

the shape of at least some of the flexible links being an N-contoured link, wherein each of said links have at least four generally longitudinally extending curved segments, each flexible link having a proximal attachment point to a curved section of one circumferential set of strut members and a distal attachment point to a curved section of a second circumferential set of strut members, each individual flexible link having a maximum circumferential extent that is approximately the same as measured from each side of a longitudinal and linearly directed line extending between the proximal attachment point and the distal attachment point of that individual flexible link to a next succeeding adjacent strut member and a next preceding adjacent strut member.

5. A stent in the form of a thin-walled, multi-cellular, tubular structure having a longitudinal axis, the stent comprising a multiplicity of circumferential sets of strut members, each set of strut members being longitudinally separated each from the other and each set of strut members forming a closed, cylindrical portion of the stem, each set of strut members comprising a multiplicity of connected curved sections and diagonal sections, the sets of strut members including end sets of strut members located at each end of the stent and central sets of strut members positioned between the end sets of strut members, at least two succeeding central strut members being coupled to a pair of opposing N-contoured links wherein each N-contoured link has a proximal end and a distal end coupled to a next succeeding and a next preceding central strut member respectively to form a dosed cell therebetween, the curved sections of the central sets of strut members having a generally greater width than the width of the curved sections of the end sets of strut members and the diagonal sections of the central sets of strut members having a greater length as compared to the length of the diagonal sections of the end sets of strut members so as to provide approximately matched radial strength for the central sets of strut members and the end sets of strut members, wherein the width of the curved sections of the central sets of strut members is at least 0.0127 mm greater than the width of the curved sections of the end sets of strut members.

6. A stent in the form of a thin-walled, multi-cellular, tubular structure having a longitudinal axis, the stent comprising a multiplicity of circumferential sets of strut members, each set of strut members being longitudinally separated each from the other and connected each to the other by one or more longitudinally extending links, each set of strut members forming a closed, cylindrical portion of the stent, each set of strut members comprising a multiplicity of connected curved sections and diagonal sections, the sets of strut members including end sets of strut members located at each end of the stent and central sets of strut members positioned between the end sets of strut members, the end sets of strut members having greater wall thickness without a coating applied thereto than the wall thickness of the central sets of strut members, said longitudinally extending links having a width less than any strut member of the end set of strut members so as to increase the radiopacity of the end sets of strut members.

7. A stent in the form of a thin-walled, multi-cellular, tubular structure having a longitudinal axis, the stent comprising a multiplicity of circumferential sets of strut members, each set of strut members being longitudinally separated each from the other and each set of strut members forming a closed, cylindrical portion of the stent, each set of strut members comprising a multiplicity of connected curved sections and diagonal sections, the sets of strut members including end sets of strut members located at each end of the stent and central sets of strut members positioned between the end sets of strut members, at least two succeeding central strut members being coupled to a pair of opposing N-contoured links wherein each N-contoured link has a proximal end and a distal end coupled to a next succeeding and a next preceding central strut member respectively to form a dosed cell therebetween, the curved sections of the central sets of strut members having a generally greater width than the width of the curved sections of the end sets of strut members and the diagonal sections of the central sets of strut members having a greater length as compared to the length of the diagonal sections of the end sets of strut members so as to provide approximately matched radial strength for the central sets of strut members and the end sets of strut members, wherein the length of the diagonal sections of the central sets of strut members is at least 0.0254 mm greater than the length of the diagonal sections of the end sets of strut members.