STENT HAVING HELICAL ELEMENTS
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.