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 . A stent comprising a main body formed from
a plurality of expandable helical segments that comprise a plurality of a single substantially S-shaped portions and one or more substantially H-shaped segments which connect a plurality of main body cylindrical elements;
said cylindrical elements comprising a plurality of first circumferential segments having a repeating pattern and second circumferential segments comprising the substantially S-shaped portion; and
wherein said S-shaped portion comprises a linear element and a curved element, said linear element lying an acute angle less than or equal to about 45 degrees relative to a cylindrical axis of the main body.
2 . The stent of claim 1 wherein the substantially S-shaped portion further comprises an angled portion connected to the linear portion at an end opposite to the curved portion.
3 . The stent of claim 2 wherein the angled portion forms an angle relative to the cylindrical axis of the stent greater than 0 degrees to about 45 degrees.
4 . The stent of claim 3 wherein the angled portion forms an angle of about 10 degrees.
5 . The stent of claim 1 wherein the substantially S-shaped portion has an amplitude ranging from about 0.5 mm to about 2.0 mm and a period ranging from about 0.5 mm to about 2.0 mm.
6 . The stent of claim 1 wherein the repeating pattern comprises a sinusoidal wave.
7 . The stent of claim 6 wherein the sinusoidal wave has an amplitude ranging from about 0.5 mm to about 2.0 mm and a period ranging from about 0.5 mm to about 2.0 mm.
8 . A stent comprising a main body formed from
a plurality of expandable helical segments that comprise a single substantially S-shaped portion and one or more substantially H-shaped segments which connect a plurality of main body cylindrical elements;
said cylindrical elements comprising a plurality of first circumferential segments having a repeating pattern and second circumferential segments having the substantially S-shaped portion; wherein said S-shaped portion comprises a linear element and a curved element, said linear element lying an acute angle less than or equal to about 45 degrees relative to a cylindrical axis of the main body; and, wherein said H-shaped segment comprises two generally parallel linear portions connected by a common connecting element, said linear portions lying at an acute angle less than or equal to about 14 degrees relative to the cylindrical axis.
9 . The stent of claim 8 wherein the substantially S-shaped portion further comprises an angled portion connected to the linear portion at an end opposite to the curved portion.
10 . The stent of claim 9 wherein the angled portion forms an angle relative to the cylindrical axis of the stent greater than 0 degrees to about 45 degrees.
11 . The stent of claim 8 wherein the substantially S-shaped portion has an amplitude ranging from about 0.5 mm to about 2.0 mm and a period ranging from about 0.5 mm to about 2.0 mm.
12 . The stent of claim 8 wherein the repeating pattern comprises a sinusoidal wave.
13 . The stent of claim 12 wherein the sinusoidal wave has an amplitude ranging from about 0.5 mm to about 2.0 mm and a period ranging from about 0.5 mm to about 2.0 mm.
14 . A stent comprising a main body formed from
a plurality of expandable helical segments that comprise a plurality of a single substantially S-shaped portions and one or more substantially H-shaped segments which connect a plurality of main body cylindrical elements;
said cylindrical elements comprising a plurality of first circumferential segments having a pattern and second circumferential segments comprising the substantially S-shaped portion; and, wherein said S-shaped portion comprises a linear element and a curved element, said linear element lying an acute angle less than or equal to about 45 degrees relative to a cylindrical axis of the main body.
15 . The stent of claim 14 wherein the pattern is repeating.
16 . The stent of claim 15 wherein the repeating pattern comprises peaks and valleys.
17 . The stent of claim 16 wherein the repeating pattern is sinusoidal.
18 . A stent comprising a main body formed from
a plurality of expandable helical segments that comprise a single substantially S-shaped portion and one or more substantially H-shaped segments which connect a plurality of main body cylindrical elements;
said cylindrical elements comprising a plurality of first circumferential segments having a repeating pattern and second circumferential segments having the substantially S-shaped portion;
and,
wherein said H-shaped segment comprises two generally parallel linear portions connected by a common connecting element, said linear portions lying at an acute angle less than or equal to about 14 degrees relative to the cylindrical axis.