Bifurcated axially flexible stent

• US 20040172126A1
• Filed: 03/08/2004
• Published: 09/02/2004
• Est. Priority Date: 09/22/1997
• Status: Active Grant

• Current Assignee: Hikmat Hojeibane
• Original Assignee: Hikmat Hojeibane
• Inventors: Hojeibane, Hikmat
• Granted Patent: US 7,842,077 B2
• Time in Patent Office: Days
• US Class Current: 623/1.15
• CPC Class Codes: A61F 2/856 Single tubular stent with a side portal passage
• CPC Class Codes: A61F 2/885 comprising a coil including a plurality of spiral or helical sections with alternate directions around a central axis
• 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 2002/91541 Adjacent bands are arranged out of phase
• CPC Class Codes: A61F 2002/9155 Adjacent bands being connected to each other
• CPC Class Codes: A61F 2002/91558 connected peak to peak

Abstract

A stent with axial flexibility, in a preferred embodiment, has a longitudinal axis and comprises a plurality of longitudinally disposed bands, wherein each band defines a generally continuous wave along a line segment parallel to the longitudinal axis. A plurality of links maintains the bands in a tubular structure. In a further embodiment of the invention, each longitudinally disposed band of the stent is connected, at a plurality of periodic locations, by a short circumferential link to an adjacent band. Further, a pair of bifurcated stents is disclosed.

Claims

1. A bifurcated stent comprising a first stent portion having first and second ends with an intermediate section therebetween, the stent further having a longitudinal axis and a plurality of longitudinally disposed cells, wherein each cell has an opening therein;

and

a second stent portion having first and second ends with an intermediate section therebetween, the stent further having a longitudinal axis and a plurality of longitudinally disposed cells, wherein each cell has an opening therein; and

each of said stent portions capable of expanding from a first respective diameter to a larger second respective diameter; and

wherein said second stent portion is configured in its said first respective diameter passing through a cell of the first stent portion in its first diameter.

2. A stent according to claim 1, each said stent formed by a series of longitudinally extending struts connected by links, wherein each link is axially displaced from any circumferentially adjacent link.

3. A stent according to claim 2, wherein, at each one of a first group of common axial positions, there is a circumferential link between each of a first set of adjacent pairs of struts.

4. A stent according to claim 3, wherein, at each one of a second group of common axial positions, there is a circumferential link between each of a second set of adjacent rows of struts, wherein, along the longitudinal axis, a common axial position occurs alternately in the first group and in the second group, and the first and second sets are selected so that a given strut is linked to a neighboring strut at only one of the first and second groups of common axial positions.

5. A stent according to claim 2, wherein the spatial frequency of the wave associated with each of the struts is decreased in a first end region lying proximate to the first end and in a second end region lying proximate to the second end, in comparison to the spatial frequency of the wave in the intermediate section.

6. A bifurcated stent system comprising in combination:

a pair of balloons aligned parallel with one another, said balloons each loaded with at least one stent and said stents maintained generally parallel with each other as they are guided along said balloon into the lumen of a body.

7. The combination of claims 6 wherein said pair of parallel stents comprises a bifurcated stent comprising:

a first stent portion having first and second ends with an intermediate section therebetween, the stent further having a longitudinal axis and a plurality of longitudinally disposed cells, wherein each cell has an opening therein; and

a second stent portion having first and second ends with an intermediate section therebetween, the stent further having a longitudinal axis and a plurality of longitudinally disposed cells, wherein each cell has an opening therein; and

each of said stent portions capable of expanding from a first respective diameter to a larger second respective diameter; and

wherein said second stent portion is configured in its said first respective diameter passing through a cell of the first stent portion in its first diameter;

and such that said respective stent portions are aligned on said balloon to be parallel to one another.

8. A combination according to claim 7, each said stent formed by a series of longitudinally extending struts connected by links, wherein each link is axially displaced from any circumferentially adjacent link.

9. The combination according to claim 8, wherein, at each one of a first group of common axial positions, there is a circumferential link between each of a first set of adjacent pairs of struts.

10. The combination according to claim 9, wherein, at each one of a second group of common axial positions, there is a circumferential link between each of a second set of adjacent rows of struts, wherein, along the longitudinal axis, a common axial position occurs alternately in the first group and in the second group, and the first and second sets are selected so that a given strut is linked to a neighboring strut at only one of the first and second groups of common axial positions.

11. The combination according to claim 8, wherein the spatial frequency of the wave associated with each of the struts is decreased in a first end region lying proximate to the first end and in a second end region lying proximate to the second end, in comparison to the spatial frequency of the wave in the intermediate section.

12. A bifurcated balloon system, said bifurcated balloon capable of being passed through a lumen of the body, said bifurcated balloon containing at least two balloons, a first of said balloons capable of being placed within a lumen and said second balloon capable of being placed in a second lumen when said first balloon is placed within said first lumen.

13. The system of claim 12 wherein said balloons are passed into the body in a parallel configuration.

14. The system of claim 13 wherein the combined diameter of said two balloons each in its unexpanded condition, is less than 6 Fr.

15. The system of claim 12 wherein each balloon carries a stent.

16. The system of claim 12 further comprising a bifurcated stent placed on said balloon combination, said bifurcated stent comprising:

a first stent portion having first and second ends with an intermediate section therebetween, the stent further having a longitudinal axis and a plurality of longitudinally disposed cells, wherein each cell has an opening therein; and

a second stent portion having first and second ends with an intermediate section therebetween, the stent further having a longitudinal axis and a plurality of longitudinally disposed cells, wherein each cell has an opening therein; and

each of said stent portions capable of expanding from a first respective diameter to a larger second respective diameter; and

wherein said second stent portion is configured in its said first respective diameter passing through a cell of the first stent portion in its first diameter.

17. A system according to claim 16, wherein each said stent formed by a series of longitudinally extending struts connected by links, wherein each link is axially displaced from any circumferentially adjacent link.

18. A system according to claim 17, wherein, at each one of a first group of common axial positions, there is a circumferential link between each of a first set of adjacent pairs of struts.

19. A system according to claim 18, wherein, at each one of a second group of common axial positions, there is a circumferential link between each of a second set of adjacent rows of struts, wherein, along the longitudinal axis, a common axial position occurs alternately in the first group and in the second group, and the first and second sets are selected so that a given strut is linked to a neighboring strut at only one of the first and second groups of common axial positions.

20. A system according to claim 17, wherein the spatial frequency of the wave associated with each of the struts is decreased in a first end region lying proximate to the first end and in a second end region lying proximate to the second end, in comparison to the spatial frequency of the wave in the intermediate section.

21. A stent system containing:

at least two stents, each of said stents having an opening in its lateral wall, and one of said stents capable of being emplaced through said lateral wall opening so that a portion of said second stent is maintained separate from said first stent; and

wherein said stents are capable of being rotated one with respect to the other in order to maintain said stents in close-fitting relationship to each other in a bifurcated lumen of the body.

22. The system of claim 21 wherein said pair of stents comprises a bifurcated stent comprising:

a first stent portion having first and second ends with an intermediate section therebetween, the stent further having a longitudinal axis and a plurality of longitudinally disposed cells, wherein each cell has an opening therein; and

a second stent portion having first and second ends with an intermediate section therebetween, the stent further having a longitudinal axis and a plurality of longitudinally disposed cells, wherein each cell has an opening therein; and

each of said stent portions capable of expanding from a first respective diameter to a larger second respective diameter; and

wherein said second stent portion is configured in its said first respective diameter passing through a cell of the first stent portion in its first diameter.

23. A method of stenting a bifurcated vessel comprising:

a) placing a bifurcated stent on a balloon, said bifurcated stent having a pair of stent sections, and said balloon having a pair of inflatable sections aligned side-by-side;

each of said stents sections having an opening in its lateral wall, and one of said stent sections capable of being emplaced through said lateral wall opening so that a portion of said second stent section is maintained separate from said first stent section; and

wherein said second stent portion is configured in its said first respective diameter passing through a cell of the first stent portion in its first diameter.