Bidirectional stent and method of use thereof
A bidirectional twistable stent is disclosed. The stent comprises a cylinder-shaped stent body having a plurality of axially arranged rows of struts encircling a central lumen and a plurality of flex connectors that connect at least two adjacent rows of struts in such a manner that allows the stent to be twisted clockwise or counter clockwise without causing deformation of any struts in the stent body. Also disclosed are the method of making the stent, method of using the stent, and a kit containing the stent.
1. A bidirectional stent, comprising:
a cylinder-shaped stent body comprising a plurality of axially arranged rows of struts encircling a central lumen, wherein each of said plurality of axially arranged rows of struts comprises struts inter-connected to form a wave-pattern with alternating peaks and troughs, wherein each peak has a tip and each trough has a bottom, and wherein said rows of struts form one or more row sections and wherein each row section comprises at least one row of struts;
a plurality of non-flex connectors that connect adjacent rows of struts within each row section, wherein each of said plurality of non-flex connectors comprises a first end and a second end, wherein said first end is attached to a tip of a peak in a first row of struts, wherein said second end is attached to a bottom of a trough in a second row of struts, wherein said first row of struts and said second row of struts are within the same row section and are adjacent to each other, and wherein no non-flex connector is present in a row section containing only one row of struts; and
a plurality of flex connectors that connect adjacent row sections, wherein each of said flex connectors comprises a first end and a second end, wherein said first end is attached to a bottom of a first trough in an edge row of struts of a first row section, said first trough has a first trough amplitude, wherein said second end is attached to a tip of a second peak in an edge row of struts of a second row section, said second peak has a second peak amplitude, and wherein said first row section is adjacent to said second row section,
wherein each of said flex connectors comprise: a first arm comprising said first end, wherein said first arm has a length that is the same as, or longer than said first trough amplitude;
a second arm comprising said second end, wherein said second arm has a length that is the same as, or longer than said second peak amplitude; and
a middle section connecting said first arm to said second arm, wherein said middle section forms a first angle with said first arm and a second angle with said second arm, wherein said first angle is in a range of about 90-160 degrees and wherein said second angle is in a range of about 90-160 degrees, and
wherein said stent body is capable of being twisted clockwise or counter-clockwise from one end of said stent body by one-fourth of a turn, or more, without causing deformation of any struts, non-flex connectors and flex-connectors in said stent body.
2. The bidirectional stent of claim 1 , wherein said first angle is in a range of about 90-120 degrees and wherein said second angle is in a range of about 90-120 degrees.
3. The bidirectional stent of claim 1 , wherein each row section contains two or more rows of struts.
4. The bidirectional stent of claim 3 , wherein each row section contains two rows of struts.
5. The bidirectional stent of claim 3 , wherein each row of struts is connected to an adjacent row of struts within the same row section by three or more non-flex connectors.
6. The bidirectional stent of claim 1 , wherein the stent body contains three or more row sections.
7. The bidirectional stent of claim 6 , wherein each row section is connected to an adjacent row section by three or more flex connectors.
8. The bidirectional stent of claim 1 , wherein peaks in the same row of struts have the same peak amplitude and wherein troughs in the same row of struts have the same trough amplitude.
9. The bidirectional stent of claim 1 , wherein each of the non-flex connectors has a length that is smaller than the row width of any of the two rows of the struts connected by said non-flex connector.
10. The bidirectional stent of claim 1 , wherein the struts, the non-flex connectors and flex connectors are made from a metal or an alloy.
11. The bidirectional stent of claim 1 , wherein said struts, said non-flex connectors and said flex connectors are made from nitinol.
12. The bidirectional stent of claim 1 , wherein said stent body is coated with a polymeric material.
13. The bidirectional stent of claim 12 , wherein said polymeric material is a biodegradable material.
14. The bidirectional stent of claim 1 , wherein said flex connectors allow said stent body to be twisted clockwise or counter-clockwise from one end of said stent body by ¼ of a turn without causing deformation of any struts and connectors in said stent body.
15. The bidirectional stent of claim 1 , wherein said flex connectors allow said stent body to be twisted clockwise or counter-clockwise from one end of said stent body by ½ of a turn without causing any deformation of said struts in said stent body.
16. The bidirectional stent of claim 1 , wherein said flex connectors allow said stent body to be twisted clockwise or counter-clockwise from one end of said stent body by a full turn without causing any deformation of said struts in said stent body.
17. A stent kit, comprising:
the bidirectional stent of claim 1 ; and
instructions for using the stent.
18. The kit of claim 17 , further comprising a guidewire.
19. The bidirectional stent of claim 1 , wherein the non-flex connectors comprise straight struts connecting the tips of the peaks in a row of struts to the tips of peaks in an adjacent row of struts.