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 having an unexpanded state, the unexpanded stent comprising:
a body defining a cylindrical axis, the body including a helical segment having a substantially H-shaped portion defining two generally parallel linear portions being angled with respect to the cylindrical axis.
2 . The stent of claim 1 , wherein the angle between the H-shaped segment and the cylindrical axis is greater than 0 degrees.
3 . The stent of claim 2 , wherein the angle between the H-shaped segment and the cylindrical axis is less than 90 degrees.
4 . An expandable stent having an unexpanded state, the unexpanded stent comprising:
a cylindrical main body defining a cylindrical axis, the main body including a plurality of helical segments, each helical segment including a substantially H-shaped segment defining two generally parallel linear portions being angled with respect to the cylindrical axis.
5 . The stent of claim 4 , wherein the angle between the H-shaped segment and the cylindrical axis is greater than 0 degrees.
6 . The stent of claim 5 , wherein the angle between the H-shaped segment and the cylindrical axis is less than 90 degrees.
7 . The stent of claim 4 , wherein each helical segment includes a substantially S-shaped segment.
8 . The stent of claim 7 , wherein each helical segment includes a plurality of substantially S-shaped segments alternating with a plurality of substantially H-shaped segments.
9 . An expandable stent having an unexpanded state, the unexpanded stent comprising:
a main body defining a cylindrical axis, the main body including a helical segment including a substantially S-shaped segment and a substantially H-shaped segment, the H-shaped segment defining two generally parallel linear portions nonparallel to the cylindrical axis.
10 . The stent of claim 9 , the linear portions are not perpendicular to the cylindrical axis.
11 . The stent of claim 9 , wherein each helical segment includes a plurality of substantially S-shaped segments alternating with a plurality of substantially H-shaped segments.