Longitudinally flexible stent

• US 8,496,699 B2
• Filed: 10/05/2010
• Issued: 07/30/2013
• Est. Priority Date: 03/01/2000
• Status: Expired due to Fees

• Current Assignee: Medinol Limited (Medinol USA Incorporated)
• Original Assignee: Medinol Limited (Medinol USA Incorporated)
• Inventors: Richter, Jacob, Pinchasik, Gregory
• Primary Examiner(s): Bui, Vy Q
• Application Number:
  US12/898,513
• Publication Number:
  US 20110022156A1
• Time in Patent Office: 1,029 Days
• Field of Search: 606/108, 606/191, 606/194, 606/198, 623/1.15
• 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 2002/91525 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 2230/0054 V-shaped

Abstract

An intravascular stent especially suited for implanting in curved arterial portions. The stent retains longitudinal flexibility after expansion. The stent is formed of intertwined meander patterns forming triangular cells. The triangular cells are adapted to provide radial support, and also to provide longitudinal flexibility after expansion. The triangular cells provide increased coverage of a vessel wall. The stent can have different portions adapted to optimize radial support or to optimize longitudinal flexibility. Loops in the stent are disposed and adapted to cooperate so that after expansion of said stent within a curved lumen, the stent is curved and cells on the outside of the curve open in length, but narrow in width whereas cells on the inside of the curve shorten in length but thicken in width to maintain a density of stent element area which much more constant than otherwise between the inside and the outside of the curve. As a result, when the stent is coated with a medicine the more constant density of stent elements results in an even dose being applied to the inside wall of the lumen, avoiding the possibility that a toxic dose be supplied at one area while a less than effective dose is applied to another area.

Claims

1. A stent having a tubular structure with a longitudinal axis comprising:

a multiplicity of first circumferential bands having loops;

a multiplicity of second circumferential bands having loops alternating with said first circumferential bands along the longitudinal axis of the stent, wherein each of said first and second circumferential bands forms a single, continuous, generally sinusoidal pattern around the circumference of the stent;

a multiplicity of sets of flexible connectors with each set of flexible connectors connecting adjacent first and second circumferential bands, each set of flexible connectors consisting of a multiplicity of individual flexible connectors, each individual flexible connector comprising a single undulating Z-shaped structure,

wherein each of said flexible connectors has at least two generally curved portions connected to at least three generally straight struts, wherein the longitudinal axis of each of said struts lies generally aligned with the longitudinal axis of the stent; and

wherein the first circumferential bands, second circumferential bands and flexible connectors comprise struts having a width in the circumferential direction, wherein the struts of the first and second circumferential bands are wider than the width of the struts of the flexible connectors.

2. A stent having a longitudinal axis along the length of the stent comprising:

a. a plurality of first loop containing sections having loops;

b. a plurality of second loop containing sections having loops alternating with said first loop containing sections;

c. each of said first and second loop containing sections forms a single, continuous, generally sinusoidal pattern around the circumference of the stent;

d. a plurality of sets of third loop containing sections having loops, each set of said third loop containing sections disposed in the general circumferential space between each adjacent pair of said first and second loop containing sections to form consecutive repeating patterns along the longitudinal axis of the stent for at least two repetitions and joined to said first and second loop containing sections directly at circumferentially offset curved portions of said first and second loop containing sections, each third loop containing section having (x) at least one loop between said curved portions of said first and second loop containing sections and (y) struts, wherein the longitudinal axis of each of said struts lies generally aligned with the longitudinal axis of the stent; and

e. wherein the loops of the first, second, and third loop containing sections comprise struts having a width in the circumferential direction, wherein the struts of the first and second loop containing sections are wider than the width of the struts of the third loop containing section.

3. A stent comprising:

a plurality of first circumferential bands consisting essentially of a pattern of first members alternating with second members joined together by loops, said first circumferential band forming a single, continuous, generally sinusoidal pattern around the circumference of the stent;

a plurality of second circumferential bands consisting essentially of a pattern of third members alternating with fourth members joined together by loops, said second circumferential band forming a single, continuous, generally sinusoidal pattern around the circumference of the stent, wherein said first circumferential bands alternate with said second circumferential bands; and

a plurality of flexible compensating members arranged in the circumferential space between every adjacent first circumferential band and second circumferential band,

wherein each said flexible compensating member includes a first leg having a first end and a second end, a second leg having a first end and a second end, and a third leg having a first end and a second end, said first end of said first leg connects to a loop of said first circumferential band, said second end of said first leg connects to said first end of said second leg, said second end of said second leg connects to said first end of said third leg, and said second end of said third leg connects to a loop of a second circumferential band;

wherein the longitudinal axis of each of said first, second and third legs lies generally aligned with the longitudinal axis of the stent.

4. A stent according to claim 3 wherein a loop connects said first leg to said second leg of a flexible compensating member.

5. A stent according to claim 3 wherein a loop connects said second leg to said third leg of a flexible compensating member.

6. A stent according to claim 3 wherein each said flexible compensating member connects a loop of a first circumferential band with a circumferentially offset loop of a second circumferential band.

7. A stent according to claim 3 wherein the loops of said first circumferential bands are out-of-phase with the loops of said second circumferential bands.

8. A stent comprising a plurality of cells, each cell comprising:

a. a first member having a first end and a second end;

b. a second member having a first end and a second end, wherein said first and second members form a first band, wherein said first band is oriented substantially perpendicular to the longitudinal axis of the stent;

c. a third member having a first end and a second end;

d. a fourth member having a first end and a second end, wherein said first end of said first member connects to said second end of said second member to form a first loop, and said first end of said third member connects with said second end of said fourth member to form a second loop, wherein said second loop is circumferentially offset from said first loop;

e. a first flexible compensating member having a first end, a second end and struts forming the shape of a Z, wherein the longitudinal axis of each of said struts lies generally aligned with the longitudinal axis of the stent, wherein said first end connects with said second end of said first member, and said second end connects with said first end of said fourth member; and

f. a second flexible compensating member having a first end, a second end and struts forming the shape of a Z, wherein the longitudinal axis of each of said struts lies generally aligned with the longitudinal axis of the stent, wherein said first end connects with said first end of said second member, and said second end connects with said second end of said third member.