Stent having helical elements

Abstract

An expandable stent comprised of a plurality of helical segments is disclosed. In one embodiment, the stent is generally cylindrical in shape having a cylindrical axis, and comprises a first and second set of helical segments. The helical segments in the first set are substantially parallel and have a first pitch forming a first helical angle with respect to the cylindrical axis. The helical segments in the second set are also generally parallel to each other and form a second pitch that differs from the first pitch, thereby forming a second helical angle with respect to the cylindrical axis. In an alternative embodiment, the stent comprises one set of helical segments and a plurality of circumferential elements that are joined together by the helical segments to form a plurality of cylindrical elements which are joined together to form a stent body. The stent may also have endzones.

1 . An expandable stent comprising:
 a main body formed from a plurality of expandable helical segments that comprise expandable circumferential segments each having a single substantially S-shaped portion and substantially H-shaped connecting segments set at an angle with respect to a main body cylindrical axis; and   a plurality of main body cylindrical elements formed from a plurality of circumferential segments joined together by the H-shaped connecting segments, the main body cylindrical elements being adjacent to one another and being attached to one another by the H-shaped connecting-segments.   
   
   
       2 . The expandable stent of  claim 1 , wherein the stent is in an unexpanded state. 
   
   
       3 . The expandable stent of  claim 1 , wherein the stent is in an expanded state. 
   
   
       4 . The expandable stent of  claim 1 , wherein the angle is at least about 14 degrees. 
   
   
       5 . The expandable stent of  claim 1 , wherein the angle is less than about 90 degrees and greater than 0 degrees. 
   
   
       6 . The expandable stent of  claim 1 , wherein each substantially S-shaped portion comprises at least one linear portion. 
   
   
       7 . The expandable stent of  claim 6 , wherein the linear portion is set at a second angle with respect to the main body cylindrical axis. 
   
   
       8 . The expandable stent of  claim 7 , wherein the second angle ranges from 0 degrees to about 45 degrees. 
   
   
       9 . An expandable stent comprising:
 a main body formed from a plurality of expandable helical segments that comprise expandable circumferential segments each having a single substantially S-shaped portion comprising at least one linear portion, wherein the linear portion is set at an angle with respect to a main body cylindrical axis; and   a plurality of main body cylindrical elements formed from a plurality of circumferential segments joined together by substantially H-shaped connecting segments, the main body cylindrical elements being adjacent to one another and being attached to one another by the H-shaped connecting-segments.   
   
   
       10 . The expandable stent of  claim 9 , wherein the substantially H-shaped connecting segments is set at a second angle with respect to the main body cylindrical axis. 
   
   
       11 . The expandable stent of  claim 10 , wherein the second angle is at least about 14 degrees. 
   
   
       12 . The expandable stent of  claim 9 , wherein the angle of the linear portion ranges from greater than 0 degrees to about 45 degrees. 
   
   
       13 . An expandable stent comprising:
 a main body formed from a plurality of expandable helical segments that comprise expandable circumferential segments each having a circumferential element comprising at least one linear portion and substantially H-shaped connecting segments set at a first angle with respect to a main body cylindrical axis; and   a plurality of main body cylindrical elements formed from a plurality of circumferential segments joined together by the H-shaped connecting segments, the main body cylindrical elements being adjacent to one another and being attached to one another by the H-shaped connecting-segments.   
   
   
       14 . The expandable stent of  claim 13 , wherein the first angle is at least about 14 degrees. 
   
   
       15 . The expandable stent of  claim 13 , wherein the first angle is less than about 90 degrees and greater than 0 degrees. 
   
   
       16 . The expandable stent of  claim 13 , wherein the linear portion of the circumferential element is set at a second angle with respect to the main body cylindrical axis. 
   
   
       17 . The expandable stent of  claim 16 , wherein the second angle ranges from 0 degrees to about 45 degrees. 
   
   
       18 . The expandable stent of  claim 13 , wherein the circumferential element comprises at least three linear portions set at a second, third and fourth angle, respectively, relative to the main body cylindrical axis wherein at least two of the angles are equal. 
   
   
       19 . The expandable stent of  claim 18 , wherein the second, third and fourth angles range from 0 to about 45 degrees with respect to the main body cylindrical axis. 
   
   
       20 . The expandable stent of  claim 13 , wherein the stent is in an expanded state.