U.S. patent application number 10/374774 was filed with the patent office on 2004-06-03 for intravascular stent.
Invention is credited to Jang, G. David.
Application Number | 20040106985 10/374774 |
Document ID | / |
Family ID | 33130338 |
Filed Date | 2004-06-03 |
United States Patent
Application |
20040106985 |
Kind Code |
A1 |
Jang, G. David |
June 3, 2004 |
Intravascular stent
Abstract
A stent comprises a first expansion strut column of first
expansion strut pairs and a second expansion strut column of second
expansion strut pairs. Each first expansion strut pair is connected
to a second expansion strut pair by a connecting strut. Each
connecting strut comprises at least one wrap portion, the at least
one wrap portion being at least partially wrapped about at least
one of the first joining portions of at least one of the first
expansion strut column and the second expansion strut column.
Inventors: |
Jang, G. David; (Redmonds,
CA) |
Correspondence
Address: |
VIDAS, ARRETT & STEINKRAUS, P.A.
6109 BLUE CIRCLE DRIVE
SUITE 2000
MINNETONKA
MN
55343-9185
US
|
Family ID: |
33130338 |
Appl. No.: |
10/374774 |
Filed: |
February 25, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10374774 |
Feb 25, 2003 |
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10206432 |
Jul 25, 2002 |
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10206432 |
Jul 25, 2002 |
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09574077 |
May 18, 2000 |
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09574077 |
May 18, 2000 |
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08845734 |
Apr 25, 1997 |
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08845734 |
Apr 25, 1997 |
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08824142 |
Mar 25, 1997 |
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6241760 |
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08845734 |
Apr 25, 1997 |
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08824866 |
Mar 26, 1997 |
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5954743 |
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08845734 |
Apr 25, 1997 |
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08824865 |
Mar 26, 1997 |
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6152957 |
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08845734 |
Apr 25, 1997 |
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08845657 |
Apr 25, 1997 |
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5922021 |
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10374774 |
Feb 25, 2003 |
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10123883 |
Apr 15, 2002 |
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10123883 |
Apr 15, 2002 |
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09839442 |
Apr 20, 2001 |
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6409761 |
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09839442 |
Apr 20, 2001 |
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08824142 |
Mar 25, 1997 |
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6241760 |
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10374774 |
Feb 25, 2003 |
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10123883 |
Apr 15, 2002 |
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10123883 |
Apr 15, 2002 |
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09839287 |
Apr 20, 2001 |
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10374774 |
Feb 25, 2003 |
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10321005 |
Dec 17, 2002 |
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10321005 |
Dec 17, 2002 |
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09839287 |
Apr 20, 2001 |
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09839287 |
Apr 20, 2001 |
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09237537 |
Jan 26, 1999 |
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6235053 |
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10374774 |
Feb 25, 2003 |
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09960861 |
Sep 21, 2001 |
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10374774 |
Feb 25, 2003 |
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09874349 |
Jun 4, 2001 |
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10374774 |
Feb 25, 2003 |
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10297372 |
Jul 18, 2003 |
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10297372 |
Jul 18, 2003 |
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PCT/US01/18419 |
Jun 5, 2001 |
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10374774 |
Feb 25, 2003 |
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09942077 |
Aug 28, 2001 |
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60017484 |
Apr 26, 1996 |
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60017484 |
Apr 26, 1996 |
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60234614 |
Sep 22, 2000 |
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60209255 |
Jun 5, 2000 |
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60209255 |
Jun 5, 2000 |
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60235164 |
Sep 23, 2000 |
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Current U.S.
Class: |
623/1.16 ;
623/23.7 |
Current CPC
Class: |
A61F 2230/0013 20130101;
A61F 2250/0067 20130101; A61F 2/91 20130101; A61F 2250/0018
20130101; A61F 2/958 20130101; A61F 2002/91525 20130101; A61F
2002/91583 20130101; A61F 2002/91558 20130101; A61F 2/915 20130101;
A61F 2002/91533 20130101 |
Class at
Publication: |
623/001.16 ;
623/023.7 |
International
Class: |
A61F 002/06 |
Claims
What is claimed is:
1. A stent comprising: a first expansion strut column, the first
expansion strut column being comprised of a plurality of adjacent
first expansion strut pairs, each first expansion strut pair having
a first expansion strut and a second expansion strut, the first
expansion strut column having a plurality of first joining
portions, the first expansion strut in communication with the
second expansion strut at a first joining portion, the first
expansion strut column having a plurality of second joining
portions, each first expansion strut pair in communication with an
adjacent first expansion strut pair at each second joining portion;
a second expansion strut column, the second expansion strut column
being comprised of a plurality of adjacent second expansion strut
pairs, each second expansion strut pair having a first expansion
strut and a second expansion strut, the second expansion strut
column having a plurality of first joining portions, the first
expansion strut in communication with the second expansion strut at
a first joining portion, the second expansion strut column having a
plurality of second joining portions, each second expansion strut
pair in communication with an adjacent second expansion strut pair
at each second joining portion; a first connecting strut column,
the first connecting strut column comprising at least one
connecting strut, the at least one connecting strut comprising a
first end region, a second end region and an intermediate region
therebetween, the first end region being engaged to a portion of
one of the first expansion strut pairs at a location in closer
proximity to the first expansion strut than to the second expansion
strut, the intermediate region comprising a plurality of bend
portions, at least a portion of the at least one connecting strut
comprising at least one wrap portion, the at least one wrap portion
being at least partially wrapped about at least one of the first
joining portions of at least one of the first expansion strut
column and the second expansion strut column.
2. The stent of claim 1 wherein the second end region is engaged to
a portion of one of the second expansion strut pairs at a location
in closer proximity to the first expansion strut than to the second
expansion strut.
3. The stent of claim 1 wherein the second end region is engaged to
a portion of one of the second expansion strut pairs at a location
substantially equal in proximity to the first expansion strut than
to the second expansion strut.
4. The stent of claim 1 further comprising a third expansion strut
column and a second connecting strut column, the third expansion
strut column being comprised of a plurality of adjacent third
expansion strut pairs, each third expansion strut pair having a
first expansion strut and a second expansion strut, the third
expansion strut column having a plurality of first joining
portions, the first expansion strut in communication with the
second expansion strut at a first joining portion, the second
expansion strut column having a plurality of second joining
portions, each third expansion strut pair in communication with an
adjacent third expansion strut pair at each second joining portion;
the second connecting strut column comprising at least one
connecting strut, the at least one connecting strut comprising a
first end region, a second end region and an intermediate region
therebetween, the first end region being engaged to a portion of
one of the second expansion strut pairs at a location in closer
proximity to the first expansion strut than to the second expansion
strut, the intermediate region comprising a plurality of bend
portions, at least a portion of the at least one connecting strut
comprising at least one wrap portion, the at least one wrap portion
being at least partially wrapped about at least one of the second
joining portions of the second expansion strut column and the first
joining portions of the third expansion strut column.
5. The stent of claim 4 wherein the second end region of the at
least one connecting strut of the second connecting strut column is
engaged to a portion of one of the third expansion strut pairs at a
location in closer proximity to the first expansion strut than to
the second expansion strut.
6. The stent of claim 4 wherein the second end region of the at
least one connecting strut of the second connecting strut column is
engaged to a portion of one of the second expansion strut pairs at
a location substantially equal in proximity to the first expansion
strut than to the second expansion strut.
7. The stent of claim 1 wherein the intermediate region of the at
least one connecting strut of the first connecting strut column
further comprises at least one substantially linear section.
8. The stent of claim 1 wherein the intermediate region of the at
least one connecting strut of the first connecting strut column
further comprises at least two substantially linear sections.
9. The stent of claim 8 wherein each substantially liner portion
intersects an adjacent substantially linear section at one of the
bend portions.
10. The stent of claim 1 wherein the intermediate region of the at
least one connecting strut of the first connecting strut column
further comprises at least three substantially linear sections.
11. The stent of claim 10 wherein each substantially liner portion
intersects an adjacent substantially linear section at one of the
bend portions.
12. The stent of claim 1 wherein the intermediate region of the at
least one connecting strut of the first connecting strut column
further comprises at least four substantially linear sections.
13. The stent of claim 12 wherein each substantially liner portion
intersects an adjacent substantially linear section at one of the
bend portions.
14. The stent of claim 1 wherein the intermediate region of the at
least one connecting strut of the first connecting strut column
further comprises at least five substantially linear sections.
15. The stent of claim 15 wherein each substantially liner portion
intersects an adjacent substantially linear section at one of the
bend portions.
16. The stent of claim 4 wherein the intermediate region of the at
least one connecting strut of the second connecting strut column
further comprises at least one substantially linear section.
17. The stent of claim 4 wherein the intermediate region of the at
least one connecting strut of the second connecting strut column
further comprises at least two substantially linear sections.
18. The stent of claim 17 wherein each substantially liner portion
of the at least one connecting strut of the second connecting strut
column intersects an adjacent substantially linear section at one
of the bend portions.
19. The stent of claim 4 wherein the intermediate region of the at
least one connecting strut of the second connecting strut column
further comprises at least three substantially linear sections.
20. The stent of claim 19 wherein each substantially liner portion
of the at least one connecting strut of the second connecting strut
column intersects an adjacent substantially linear section at one
of the bend portions.
21. The stent of claim 4 wherein the intermediate region of the at
least one connecting strut of the second connecting strut column
further comprises at least four substantially linear sections.
22. The stent of claim 21 wherein each substantially liner portion
of the at least one connecting strut of the second connecting strut
column intersects an adjacent substantially linear section at one
of the bend portions.
23. The stent of claim 4 wherein the intermediate region of the at
least one connecting strut of the second connecting strut column
further comprises at least five substantially linear sections.
24. The stent of claim 15 wherein each substantially liner portion
of the at least one connecting strut of the second connecting strut
column intersects an adjacent substantially linear section at one
of the bend portions.
25. The stent of claim 1 wherein the at least one connecting strut
comprises a single wrap portion, the wrap portion being at least
partially wrapped about at least one of the first joining portions
of the first expansion strut column.
26. The stent of claim 1 wherein the at least one connecting strut
comprises a single wrap portion, the wrap portion being at least
partially wrapped about at least one of the first joining portions
of the second expansion strut column.
27. The stent of claim 1 wherein the at least one connecting strut
comprises a first wrap portion and a second wrap portion, the first
wrap portion being at least partially wrapped about at least one of
the first joining portions of the first expansion strut column, the
second wrap portion being at least partially wrapped about at least
one of the first joining portions of the second expansion strut
column.
28. The stent of claim 1 wherein the at least one wrap portion and
the at least one first joining portion define a slot region, the
slot region having a slot region width, the at least one connecting
strut having a connecting strut width, the slot region width being
less than the connecting strut width.
29. The stent of claim 1 wherein the at least one wrap portion is
substantially parallel to the first joining portion about which the
at least one wrap portion is wrapped.
30. The stent of claim 28 wherein the at least one wrap portion is
substantially parallel to the first joining portion about which the
at least one wrap portion is wrapped.
31. The stent of claim 1 wherein the at least one wrap portion is
an extension of at least one of the first expansion strut and the
second expansion strut of the first expansion strut pair.
32. The stent of claim 1 wherein the at least one wrap portion is
an extension of at least one of the first expansion strut and the
second expansion strut of the second expansion strut pair.
33. The stent of claim 4 wherein the at least one connecting strut
of the first connecting strut column and the at least one
connecting strut of the second connecting strut column have a
different shape from one another.
34. The stent of claim 33 wherein the at least one connecting strut
of the first connecting strut column and the at least one
connecting strut of the second connecting strut column have a
different length from one another.
35. The stent of claim 33 wherein the at least one connecting strut
of the first connecting strut column and the at least one
connecting strut of the second connecting strut column have
substantially the same length.
36. The stent of claim 4 wherein the at least one connecting strut
of the first connecting strut column and the at least one
connecting strut of the second connecting strut column have a
different length from one another.
37. The stent of claim 4 wherein the at least one connecting strut
of the first connecting strut column and the at least one
connecting strut of the second connecting strut column have
substantially the same length.
38. The stent of claim 4 wherein the at least one connecting strut
of the first connecting strut column having a first connecting
strut width and the at least one connecting strut of the second
connecting strut column having a second connecting strut width, the
first connecting strut width and the second connecting strut width
being different from one another.
39. The stent of claim 4 wherein the at least one connecting strut
of the first connecting strut column having a first connecting
strut width and the at least one connecting strut of the second
connecting strut column having a second connecting strut width, the
first connecting strut width and the second connecting strut width
being substantially the same.
40. The stent of claim 1 wherein the intermediate region of the at
least one connecting strut comprises at least three bend
portions.
41. The stent of claim 1 wherein the intermediate region of the at
least one connecting strut comprises at least four bend
portions.
42. The stent of claim 1 wherein the intermediate region of the at
least one connecting strut comprises at least five bend
portions.
43. The stent of claim 1 wherein the first end region of the at
least one connecting strut is engaged to a first expansion strut
pair at an intersection of the first expansion strut and the first
joining portion of the first expansion strut pair.
44. The stent of claim 1 wherein the first end region of the at
least one connecting strut is engaged to a first expansion strut
pair at an intersection of the second expansion strut and the first
joining portion of the first expansion strut pair.
45. The stent of claim 1 wherein the first end region of the at
least one connecting strut is engaged to a first expansion strut
pair at a location adjacent to an intersection of the first
expansion strut and the first joining portion of the first
expansion strut pair.
46. The stent of claim 1 wherein the first end region of the at
least one connecting strut is engaged to a first expansion strut
pair at a location adjacent to an intersection of the second
expansion strut and the first joining portion of the first
expansion strut pair.
47. The stent of claim 45 wherein at least a portion of the at
least one connecting strut is substantially parallel to the first
expansion strut of the first expansion strut pair to which the at
least one connecting strut is engaged.
48. The stent of claim 47 wherein the at least a portion of the at
least one connecting strut is substantially parallel to the first
joining portion of the first expansion strut pair to which the at
least one connecting strut is engaged.
49. The stent of claim 46 wherein at least a portion of the at
least one connecting strut is substantially parallel to the second
expansion strut of the first expansion strut pair to which the at
least one connecting strut is engaged.
50. The stent of claim 49 wherein the at least a portion of the at
least one connecting strut is substantially parallel to the first
joining portion of the first expansion strut pair to which the at
least one connecting strut is engaged.
51. The stent of claim 1 wherein the second end region of the at
least one connecting strut is engaged to a second expansion strut
pair at an intersection of the first expansion strut and the first
joining portion of the second expansion strut pair.
52. The stent of claim 1 wherein the second end region of the at
least one connecting strut is engaged to a second expansion strut
pair at an intersection of the second expansion strut and the first
joining portion of the first expansion strut pair.
53. The stent of claim 1 wherein the second end region of the at
least one connecting strut is engaged to a second expansion strut
pair at a location adjacent to an intersection of the first
expansion strut and the first joining portion of the second
expansion strut pair.
54. The stent of claim 1 wherein the second end region of the at
least one connecting strut is engaged to a second expansion strut
pair at a location adjacent to an intersection of the second
expansion strut and the first joining portion of the second
expansion strut pair.
55. The stent of claim 51 wherein at least a portion of the at
least one connecting strut is substantially parallel to the first
expansion strut of the second expansion strut pair to which the at
least one connecting strut is engaged.
56. The stent of claim 55 wherein the at least a portion of the at
least one connecting strut is substantially parallel to the first
joining portion of the second expansion strut pair to which the at
least one connecting strut is engaged.
57. The stent of claim 52 wherein at least a portion of the at
least one connecting strut is substantially parallel to the second
expansion strut of the second expansion strut pair to which the at
least one connecting strut is engaged.
58. The stent of claim 57 wherein the at least a portion of the at
least one connecting strut is substantially parallel to the first
joining portion of the second expansion strut pair to which the at
least one connecting strut is engaged.
59. The stent of claim 1 wherein the at least one wrap portion of
the at least one connecting strut extends longitudinally and
circumferentially away from the first expansion strut pair to which
the at least one connecting strut is engaged.
60. The stent of claim 1 wherein the at least one wrap portion of
the at least one connecting strut extends longitudinally and
circumferentially away from the second expansion strut pair to
which the at least one connecting strut is engaged.
61. The stent of claim 1 wherein at least a portion of the first
expansion strut and at least a portion of the second expansion
strut of each first expansion strut pair being substantially
parallel.
62. The stent of claim 61 wherein the at least a portion of the
first expansion strut and the at least a portion of the second
expansion strut are not parallel to a longitudinal axis of the
stent.
63. The stent of claim 1 wherein at least a portion of the first
expansion strut and at least a portion of the second expansion
strut of each second expansion strut pair being substantially
parallel.
64. The stent of claim 63 wherein the at least a portion of the
first expansion strut and the at least a portion of the second
expansion strut are not parallel to a longitudinal axis of the
stent.
65. The stent of claim 1 wherein at least a portion of at least one
of the first expansion strut and the second expansion strut of each
first expansion strut pair being substantially parallel to a
longitudinal axis of the stent.
66. The stent of claim 1 wherein at least a portion of at least one
of the first expansion strut and the second expansion strut of each
second expansion strut pair being substantially parallel to a
longitudinal axis of the stent.
67. The stent of claim 1 wherein at least one of the first
expansion strut and the second expansion strut of a first expansion
strut pair comprised at least one stepped notch.
68. The stent of claim 1 wherein at least one of the first
expansion strut and the second expansion strut of a second
expansion strut pair comprises at least one stepped notch.
69. The stent of claim 67 wherein the first end region of the at
least one connecting strut is engaged to the at least one stepped
notch.
70. The stent of claim 68 wherein the second end region of the at
least one connecting strut is engaged to the at least one stepped
notch.
71. The stent of claim 1 wherein the first end region and the
second end region of the at least one connecting strut have an
ipsilateral orientation relative to one another.
72. The stent of claim 1 wherein the first end region and the
second end region of the at least one connecting strut have a
contra-lateral orientation relative to one another.
73. The stent of claim 1 wherein the at least two connecting struts
of the first connecting strut column and a first expansion strut
pair and a second expansion strut pair respectively engaged each
thereto form an asymmetrical cell space.
74. The stent of claim 73 wherein the at least two connecting
struts of the first connecting strut column and a first expansion
strut pair and a second expansion strut pair respectively engaged
each thereto define a cell perimeter about the asymmetrical cell
space, the cell perimeter is at least 5 mm in length.
75. The stent of claim 73 wherein the at least two connecting
struts of the first connecting strut column and a first expansion
strut pair and a second expansion strut pair respectively engaged
each thereto define a cell perimeter about the asymmetrical cell
space, the cell perimeter is greater than 7 mm in length.
76. The stent of claim 1 wherein the plurality of bend portions
comprise at least six bend portions.
77. The stent of claim 1 wherein the stent further comprises at
least one radiopaque marker.
78. The stent of claim 77 wherein at least one of the first
expansion strut pairs is configured to retain the at least one
radiopaque marker.
79. The stent of claim 77 wherein at least one of the second
expansion strut pairs is configured to retain the at least one
radiopaque marker.
80. The stent of claim 77 wherein the at least one radiopaque
marker is selected from at least one member of the group consisting
of: at least one radiopaque rivet, at least one radiopaque band, at
least one radiopaque coating and any combinations thereof.
81. The stent of claim 1 wherein at least one of the first
expansion strut and second expansion strut of a first expansion
strut pair having at least one expansion strut bend.
82. The stent of claim 1 wherein at least one of the first
expansion strut and second expansion strut of a second expansion
strut pair having at least one expansion strut bend.
83. The stent of claim 81 wherein the first end region of the at
least one connecting strut is engaged to the at least one expansion
strut bend.
84. The stent of claim 82 wherein the second end region of the at
least one connecting strut is engaged to the at least one expansion
strut bend.
85. The stent of claim 1 wherein each first expansion strut pair of
the first expansion strut column is both circumferentially and
longitudinally offset relative to the second expansion strut pair
of the second expansion strut column to which the first expansion
strut pair is connected.
86. The stent of claim 1 wherein each first expansion strut pair of
the first expansion strut column is only longitudinally offset
relative to the second expansion strut pair of the second expansion
strut column to which the first expansion strut pair is
connected.
87. The stent of claim 1 wherein the at least one wrap portion of
the at least one connecting strut has at least one substantially
linear section.
88. The stent of claim 87 wherein the at least one substantially
linear section of the wrap portion is engaged to a stepped notch of
one of the first expansion strut and second expansion strut.
89. The stent of claim 88 wherein the at least one substantially
linear section of the wrap portion and the first expansion strut or
second expansion strut to which it is engaged are substantially
parallel.
90. The stent of claim 88 wherein the at least one substantially
linear section of the wrap portion and the first expansion strut or
second expansion strut to which it is engaged define an angle of
about 180 to about 135 degrees.
91. The stent of claim 88 wherein the at least one substantially
linear section of the wrap portion and the first expansion strut or
second expansion strut to which it is engaged define an angle of
about 135 degrees or more.
92. The stent of claim 88 wherein the at least one substantially
linear section extends laterally away from the stepped notch.
93. The stent of claim 1 wherein the at least one wrap portion of
the at least one connecting strut comprises a first substantially
linear section of the at least one connecting strut, the first
substantially linear section extending longitudinally away from the
first expansion strut pair to which it is engaged and a second
substantially linear section of the at least one connecting strut
extending from the first substantially linear section in a
direction toward the first joining portion of the first expansion
strut pair.
94. The stent of claim 93 wherein the at least one connecting strut
further comprises a third section extending from the second
substantially linear section in a direction toward the second
expansion strut pair to which the at least one connecting strut is
engaged.
95. The stent of claim 93 wherein the first substantially linear
section is engaged to a stepped notch of one of the first expansion
strut and second expansion strut of the first expansion strut
pair.
96. The stent of claim 94 wherein the third substantially linear
section is engaged to a stepped notch of one of the first expansion
strut and second expansion strut of the second expansion strut
pair.
97. The stent of claim 1 wherein the intermediate portion of the at
least one connecting strut is further comprised of at least two
substantially linear sections, the at least two substantially
linear sections intersecting at an intersection, the intersection
of the at least two substantially linear sections defining a slant
angle.
98. The stent of claim 1 wherein the intermediate portion of the at
least one connecting strut is further comprised of at least two
substantially linear sections, the at least two substantially
linear sections intersecting at an intersection, the intersection
of the at least two substantially linear sections defining a radius
of curvature.
99. The stent of claim 97 wherein the slant angle is obtuse.
100. The stent of claim 30 wherein the slot region width is about
0.0025 inch and the connecting strut width is about 0.0030
inch.
101. The stent of claim 1 wherein the stent is configured to
deliver at least one therapeutic agent.
102. The stent of claim 1 wherein at least a portion of the stent
is coated with at least one therapeutic agent.
103. The stent of claim 101 wherein the at least one therapeutic
agent is at least one non-genetic therapeutic agent selected from
at least one member of the group consisting of: anti-thrombogenic
agents such as heparin, heparin derivatives, urokinase, and PPack
(dextrophenylalanine proline arginine chloromethylketone);
anti-proliferative agents such as enoxaprin, angiopeptin,
monoclonal antibodies capable of blocking smooth muscle cell
proliferation, hirudin, and acetylsalicylic acid; anti-inflammatory
agents such as dexamethasone, prednisolone, corticosterone,
budesonide, estrogen, sulfasalazine, and mesalamine;
antineoplastic/antiproliferative/anti-miotic agents such as
paclitaxel, 5-fluorouracil, cisplatin, vinblastine, vincristine,
epothilones, endostatin, angiostatin and thymidine kinase
inhibitors; anesthetic agents such as lidocaine, bupivacaine and
ropivacaine; anti-coagulants such as D-Phe-Pro-Arg chloromethyl
keton, an RGD peptide-containing compound, heparin, antithrombin
compounds, platelet receptor antagonists, anti-thrombin antibodies,
anti-platelet receptor antibodies, aspirin, prostaglandin
inhibitors, platelet inhibitors and tick antiplatelet peptides;
vascular cell growth promoters such as growth factor inhibitors,
growth factor receptor antagonists, transcriptional activators, and
translational promoters, vascular cell growth inhibitors such as
growth factor inhibitors, growth factor receptor antagonists,
transcriptional repressors, translational repressors, replication
inhibitors, inhibitory antibodies, antibodies directed against
growth factors, bifunctional molecules consisting of a growth
factor and a cytotoxin; bifunctional molecules consisting of an
antibody and a cytotoxin; cholesterol-lowering agents; vasodilating
agents; and agents which interfere with endogenous vascoactive
mechanisms, and any combinations thereof.
104. The stent of claim 101 wherein the at least one therapeutic
agent is at least one genetic therapeutic agent selected from at
least one member of the group consisting of: anti-sense DNA and
RNA; DNA coding for anti-sense RNA, tRNA or rRNA to replace
defective or deficient endogenous molecules; angiogenic factors
including growth factors such as acidic and basic fibroblast growth
factors, vascular endothelial growth factor, epidermal growth
factor, transforming growth factor .alpha. and .beta.,
platelet-derived endothelial growth factor, platelet-derived growth
factor, tumor necrosis factor .alpha., hepatocyte growth factor and
insulin like growth factor; cell cycle inhibitors including CD
inhibitors, thymidine kinase ("TK") and other agents useful for
interfering with cell proliferation; at least one of the family of
bone morphogenic proteins ("BMP's") such as BMP-2, BMP-3, BMP-4,
BMP-5, BMP-6 (Vgr-1), BMP-7 (OP-1), BMP-8, BMP-9, BMP-10, BMP-11,
BMP-12, BMP-13, BMP-14, BMP-15, and BMP-16. Any of BMP-2, BMP-3,
BMP-4, BMP-5, BMP-6 and BMP-7; dimeric proteins such as homodimers,
heterodimers, or combinations thereof, alone or together with other
molecules; molecules capable of inducing an upstream or downstream
effect of a BMP such as "hedgehog" proteins, or the DNA's encoding
them and any combinations thereof.
105. The stent of claim 101 wherein the at least one therapeutic
agent is at least one type of cellular material selected from at
least one member of the group consisting of: cells of human origin
(autologous or allogeneic); cells of non-human origin (xenogeneic)
and any combination thereof
106. The stent of claim 101 wherein the at least one therapeutic
agent comprises at least one polymer coating, the at least one
coating selected from at least one member of the group consisting
of: polycarboxylic acids; cellulosic polymers, including cellulose
acetate and cellulose nitrate; gelatin; polyvinylpyrrolidone;
cross-linked polyvinylpyrrolidone; polyanhydrides including maleic
anhydride polymers; polyamides; polyvinyl alcohols; copolymers of
vinyl monomers such as EVA; polyvinyl ethers; polyvinyl aromatics;
polyethylene oxides; glycosaminoglycans; polysaccharides;
polyesters including polyethylene terephthalate; polyacrylamides;
polyethers; polyether sulfone; polycarbonate; polyalkylenes
including polypropylene, polyethylene and high molecular weight
polyethylene; halogenated polyalkylenes including
polytetrafluoroethylene; polyurethanes; polyorthoesters; proteins;
polypeptides; silicones; siloxane polymers; polylactic acid;
polyglycolic acid; polycaprolactone; polyhydroxybutyrate valerate
and blends and copolymers thereof; coatings from polymer
dispersions such as polyurethane dispersions (BAYHDROL.RTM., etc.),
fibrin, collagen and derivatives thereof; polysaccharides such as
celluloses, starches, dextrans, alginates and derivatives;
hyaluronic acid; squalene emulsions; polyacrylic acid, a copolymer
of polylactic acid and polycaprolactone; medical-grade
biodegradable materials such as PGA-TMC, Tyrosine-Derived
Polycarbonates and arylates; polycaprolactone co butyl acrylate and
other co polymers; Poly-L-lactic acid blends with DL-Lactic Acid;
Poly(lactic acid-co-glycolic acid); polycaprolactone co PLA;
polycaprolactone co butyl acrylate and other copolymers;
Tyrosine-Derived Polycarbonates and arylate; poly amino acid;
polyphosphazenes; polyiminocarbonates;
polydimethyltrimethylcarbonates; biodegradable CA/PO.sub.4's;
cyanoacrylate; 50/50 DLPLG; polydioxanone; polypropylene fumarate;
polydepsipeptides; macromolecules such as chitosan and
Hydroxylpropylmethylcellulose; surface erodible material; maleic
anhydride copolymers; zinc-calcium phosphate; amorphous
polyanhydrides; sugar; carbohydrate; gelatin; biodegradable
polymers; and polymers dissolvable in bodily fluids; and any
combinations thereof.
107. The stent of claim 1 wherein the stent defines a plurality of
cavities.
108. The stent of claim 107 wherein at least one of the plurality
of cavities extend through at least one of the first expansion
strut, the second expansion strut, the first joining portion, the
second joining portion, and the at least one connecting strut.
109. The stent of claim 107 wherein at least one of the plurality
of cavities extends only partially through at least one of the
first expansion strut, the second expansion strut, the first
joining portion, the second joining portion, and the at least one
connecting strut.
110. The stent of claim 1 wherein the stent is at least partially
constructed from a shape memory material.
111. The stent of claim 1 wherein the stent is at least partially
constructed form nitinol.
112. The stent of claim 1 wherein the stent is in an expanded
state.
113. The stent of claim 1 wherein the stent is in the unexpanded
state.
114. The stent of claim 1 wherein the stent is self-expandable.
115. The stent of claim 1 wherein the stent is balloon
expandable.
116. The stent of claim 1 wherein the stent is hybrid
expandable.
117. The stent of claim 1 wherein the second end region is engaged
to a portion of one of the second expansion strut pairs at a
location in closer proximity to the second expansion strut than to
the first expansion strut.
118. The stent of claim 4 wherein the second end region of the at
least one connecting strut of the second connecting strut column is
engaged to a portion of one of the third expansion strut pairs at a
location in closer proximity to the second expansion strut than to
the first expansion strut.
119. The stent of claim 1 wherein at least a portion of the
intermediate region of the at least one connecting strut extends
longitudinally and circumferentially away from the first end region
of the same connecting strut.
120. The stent of claim 1 wherein at least a portion of the
intermediate region of the at least one connecting strut extends
longitudinally and circumferentially away from the second end
region of the same connecting strut.
121. The stent of claim 4 wherein at least a portion of the
intermediate region of the at least one connecting strut extends
longitudinally and circumferentially away from the first end region
of the same connecting strut.
122. The stent of claim 4 wherein at least a portion of the
intermediate region of the at least one connecting strut extends
longitudinally and circumferentially away from the second end
region of the same connecting strut.
123. The stent of claim 1 wherein at least a portion of the first
expansion strut and at least a portion of the second expansion
strut of each first expansion strut pair are substantially not
parallel.
124. The stent of claim 1 wherein at least a portion of the first
expansion strut and at least a portion of the second expansion
strut of each second expansion strut pair are substantially not
parallel.
125. The stent of claim 77 wherein the at least one radiopaque
marker is positioned at about a distal region of the stent.
126. The stent of claim 77 wherein the at least one radiopaque
marker is positioned at about a proximal region of the stent.
127. The stent of claim 77 wherein the at least one radiopaque
marker is positioned at about a middle region of the stent.
128. The stent of claim 30 wherein the slot region width is about
0.0015 inch and the connecting strut width is about at least 0.002
inch.
129. A system for delivering the stent of claim 1 into a body lumen
comprising: A stent delivery catheter, the stent in an unexpanded
state be disposed about a portion of the catheter, the stent being
expandable from the unexpanded state to an expanded state.
130. The system of claim 129 wherein the catheter further comprises
a medical balloon, the stent being disposed about at least a
portion of the medical balloon.
131. A stent comprising: a first expansion strut column, the first
expansion strut column being comprised of a plurality of adjacent
first expansion strut pairs, each first expansion strut pair having
a first expansion strut and a second expansion strut, the first
expansion strut column having a plurality of distal joining
portions, the first expansion strut in communication with the
second expansion strut at a distal joining portion, the first
expansion strut column having a plurality of proximal joining
portions, each first expansion strut pair in communication with an
adjacent first expansion strut pair at each proximal joining
portion; a second expansion strut column, the second expansion
strut column being comprised of a plurality of adjacent second
expansion strut pairs, each second expansion strut pair having a
first expansion strut and a second expansion strut, the second
expansion strut column having a plurality of proximal joining
portions, the first expansion strut in communication with the
second expansion strut at a proximal joining portion, the second
expansion strut column having a plurality of distal joining
portions, each second expansion strut pair in communication with an
adjacent second expansion strut pair at each distal joining
portion; a first connecting strut column, the first connecting
strut column comprising at least one connecting strut, the at least
one connecting strut having a strut width, the at least one
connecting strut comprising a first end region, a second end region
and an intermediate portion therebetween, the first end region
being engaged to a portion of one of the first expansion strut
pairs, the second end region being engaged to a portion of one of
the second expansion strut pairs, at least a portion of the
intermediate region and at least a portion of at least one of the
distal joining portions of the first expansion strut column
defining a slot region, the slot region defining a width, the width
of the slot region being no greater than the strut width of the at
least one connecting strut, the intermediate region comprising at
least two bend portions.
132. A stent comprising: a first expansion strut column, the first
expansion strut column being comprised of a plurality of adjacent
first expansion strut pairs, each first expansion strut pair having
a first expansion strut and a second expansion strut, the first
expansion strut column having a plurality of first joining
portions, the first expansion strut in communication with the
second expansion strut at a first joining portion, the first
expansion strut column having a plurality of second joining
portions, each first expansion strut pair in communication with an
adjacent first expansion strut pair at each second joining portion;
a second expansion strut column, the second expansion strut column
being comprised of a plurality of adjacent second expansion strut
pairs, each second expansion strut pair having a first expansion
strut and a second expansion strut, the second expansion strut
column having a plurality of first joining portions, the first
expansion strut in communication with the second expansion strut at
a proximal joining portion, the second expansion strut column
having a plurality of second joining portions, each second
expansion strut pair in communication with an adjacent second
expansion strut pair at each second joining portion; a first
connecting strut column, the first connecting strut column
comprising at least one connecting strut, the at least one
connecting strut having a strut width, the at least one connecting
strut comprising a first end region, a second end region and an
intermediate region therebetween, the first end region being
engaged to a portion of one of the first expansion strut pairs, the
second end region being engaged to a portion of one of the second
expansion strut pairs, at least a portion of the intermediate
region and at least a portion of at least one of the first joining
portions of at least one of the first expansion strut column and
second expansion strut column defining a slot region, the slot
region defining a width, the width of the slot region being no
greater than the strut width of the at least one connecting strut,
the intermediate region comprising at least two bend portions.
133. A stent comprising: a plurality of substantially serpentine
bands including a first substantially serpentine band and a second
substantially serpentine band, the first substantially serpentine
band and the second substantially serpentine band being connected
by at least one connection member, the at least one connection
member having a connection member width, the first substantially
serpentine band having a plurality of first end portions and a
plurality of second end portions, the second substantially
serpentine band having a plurality of first end portions and a
plurality of second end portions, the at least one connection
member and at least one first end portion of at least one of the
first substantially serpentine band and the second serpentine band
forming a slot region, the slot region having a slot width, the
slot width being no greater than the connection member width, the
at least one connection member having at least two bend
portions.
134. A stent comprising: a plurality of substantially serpentine
bands including a first substantially serpentine band and a second
substantially serpentine band, the first substantially serpentine
band and the second substantially serpentine band being connected
by at least one connection member, the first substantially
serpentine band having a plurality of first end portions and a
plurality of second end portions, the second substantially
serpentine band having a plurality of first end portions and a
plurality of second end portions, the at least one connection
member comprising at least one wrap portion, the at least one wrap
portion extending away from one of the plurality first end potions
and wrapping around at least a portion of the first end potion from
which it extends, the at least one connection member having a
plurality of bends.
135. A stent comprising: a plurality of interconnected first
expansion struts, the first expansion struts forming a first
expansion column having a proximal end region and a distal end
region, each first expansion strut in communication at a proximal
end with one first expansion strut adjacent thereto and at a distal
end with another first expansion strut adjacent thereto; a
plurality of interconnected second expansion struts, the second
expansion struts forming a second expansion column having a
proximal end region and a distal end region, each second expansion
strut in communication at a proximal end with one second expansion
strut adjacent thereto and at a distal end with another second
expansion strut adjacent thereto; a first connecting strut column
comprising a plurality of first connecting struts, each first
connecting strut having a first end region extending from the
distal end region of the first expansion column at a location in
closer proximity to one first expansion strut than to any other of
the plurality of first expansion struts, a second end region
extending from the proximal end region of the second expansion
column at a location in closer proximity to one second expansion
strut than to any other of the plurality of second expansion struts
and an intermediate region between the first end region and the
second end region, the intermediate region defining at least two
bends of each first connecting strut, at least a portion of each
first connecting strut comprising at least one wrap portion, the at
least one wrap portion being at least partially wrapped about at
least a portion of at least one of the distal end of one first
expansion strut and the proximal end of one second expansion strut.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S.
application Ser. No. 10/206,432 filed Jul. 25, 2002 which is a
continuation of U.S. application Ser. No. 09/574,077 filed May 18,
2000 which is a continuation of U.S. application Ser. No.
08/845,734 filed Apr. 25, 1997, now abandoned which is a
continuation-in-part of U.S. application Ser. No. 08/824,142 filed
Mar. 25, 1997, issued as U.S. Pat. No. 6,241,760 and which is a
continuation-in-part of U.S. application Ser. No. 08/824,866 filed
Mar. 26, 1997, issued as U.S. Pat. No. 5,954,743 and which is a
continuation-in-part of U.S. application Ser. No. 08/824,865 filed
Mar. 26, 1997, issued as U.S. Pat. No. 6,152,957 and which is a
continuation-in-part of U.S. application Ser. No. 08/845,657 filed
Apr. 25, 1997, issued as U.S. Pat. No. 5,922,021 and which claims
benefit of U.S. Provisional Application No. 60/017,484 filed Apr.
26, 1996.
[0002] The present application is also a continuation-in-part of
U.S. application Ser. No. 10/123,883 filed Apr. 15, 2002 which is a
continuation of U.S. application Ser. No. 09/839,442 filed Apr. 20,
2001, issued as U.S. Pat. No. 6,409,761 which is a continuation of
U.S. application Ser. No. 08/824,142 filed Mar. 25, 1997, issued as
U.S. Pat. No. 6,241,760 which also claims the benefit of U.S.
Provisional Application No. 60/017,484 filed Apr. 26, 1996. U.S.
application Ser. No. 10/123,883, from which the present application
is a continuation-in-part, is also a continuation of U.S.
application Ser. No. 09/839,287 filed Apr. 20, 2001 which is a
continuation of U.S. application Ser. No. 09/237,537 filed Jan. 26,
1999, issued as U.S. Pat. No. 6,235,053 which claims benefit of
U.S. Provisional Application No. 60/073,412 filed Feb. 2, 1998.
[0003] This application is also continuation-in-part of U.S.
application Ser. No. 10/321,005 filed Dec. 17, 2002 which is a
continuation of U.S. application Ser. No. 09/839,287 filed Apr. 20,
2001 which is a continuation of U.S. application Ser. No.
09/237,537 filed Jan. 26, 1999, issued as U.S. Pat. No. 6,235,053
which claims benefit of U.S. Provisional Application No. 60/073,412
filed Feb. 2, 1998.
[0004] The present application is also a continuation-in-part of
U.S. application Ser. No. 09/960,861 filed Sep. 21, 2001 which
claims benefit of U.S. Provisional Application No. 60/234,614 filed
Sep. 22, 2000.
[0005] This application is also a continuation-in-part of U.S.
application Ser. No. 09/874349 filed Jun. 4, 2001 which claims
priority to U.S. Provisional Application No. 60/209255 filed Jun.
5, 2000. The present application is also a continuation-in-part of
U.S. application Ser. No. 10/297372 filed Dec. 5, 2002, which is a
national stage application from International Application No.
PCT/US01/18419 filed Jun. 5, 2001, which claims priority to U.S.
Provisional Application No. 60/209255 filed Jun. 5, 2000.
[0006] This application is also a continuation-in-part of U.S.
application Ser. No. 09/942,077 filed Aug. 28, 2001 which claims
benefit of U.S. Provisional Application No. 60/235,164 filed Sep.
23, 2000.
[0007] The contents of all U.S. patents and applications cited
above are incorporated herein by reference in their entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
[0008] Not Applicable
BACKGROUND OF THE INVENTION
[0009] Stents, grafts, stent-grafts, vena cava filters and similar
implantable medical devices, collectively referred to hereinafter
as stents, are radially expandable endoprostheses which are
typically intravascular implants capable of being implanted
transluminally and enlarged radially after being introduced
percutaneously. Stents may be implanted in a variety of body lumens
or vessels such as within the vascular system, urinary tracts, bile
ducts, etc. Stents may be used to reinforce body vessels and to
prevent restenosis following angioplasty in the vascular system.
They may be self-expanding, mechanically expandable or hybrid
expandable.
[0010] Stents are generally tubular devices for insertion into body
lumens. However, it should be noted that stents may be provided in
a wide variety of sizes and shapes. Balloon expandable stents
require mounting over a balloon, positioning, and inflation of the
balloon to expand the stent radially outward. Self-expanding stents
expand into place when unconstrained, without requiring assistance
from a balloon. A self-expanding stent is biased so as to expand
upon release from the delivery catheter. Some stents may be
characterized as hybrid stents which have some characteristics of
both self-expandable and balloon expandable stents.
[0011] Due to the branching nature of the human vasculature it is
not uncommon for stenoses to form at any of a wide variety of
vessel bifurcations. A bifurcation is an area of the vasculature or
other portion of the body where a first (or parent) vessel is
bifurcated into two or more branch vessels. In some cases it may be
necessary to implant multiple stents at the bifurcation in order to
address a stenosis located thereon. Alternatively, a stent may be
provided with multiple sections or branches that may be deployed
within the branching vessels of the bifurcation.
[0012] Stents may be constructed from a variety of materials such
as stainless steel, Elgiloy, nickel, titanium, nitinol, shape
memory polymers, etc. Stents may also be formed in a variety of
manners as well. For example a stent may be formed by etching or
cutting the stent pattern from a tube or section of stent material;
a sheet of stent material may be cut or etched according to a
desired stent pattern whereupon the sheet may be rolled or
otherwise formed into the desired substantially tubular, bifurcated
or other shape of the stent; one or more wires or ribbons of stent
material may be woven, braided or otherwise formed into a desired
shape and pattern.
[0013] Typically, a stent is implanted in a blood vessel or other
body lumen at the site of a stenosis or aneurysm by so-called
"minimally invasive techniques" in which the stent is compressed
radially inwards and is delivered by a catheter to the site where
it is required through the patient's skin or by a "cut down"
technique in which the blood vessel concerned is exposed by minor
surgical means. When the stent is positioned at the correct
location, the catheter is withdrawn and the stent is caused or
allowed to expand to a predetermined diameter in the vessel.
[0014] Despite the wide variety of stents presently available,
there remains a desire to provide stents and stent designs which
provide a more optimized combination of improved flexibility and
good vessel coverage.
[0015] All US patents and applications and all other published
documents mentioned anywhere in this application are incorporated
herein by reference in their entirety.
[0016] Without limiting the scope of the invention a brief summary
of some of the claimed embodiments of the invention is set forth
below. Additional details of the summarized embodiments of the
invention and/or additional embodiments of the invention may be
found in the Detailed Description of the Invention below.
[0017] A brief abstract of the technical disclosure in the
specification is provided as well only for the purposes of
complying with 37 C.F.R. 1.72. The abstract is not intended to be
used for interpreting the scope of the claims.
BRIEF SUMMARY OF THE INVENTION
[0018] In light of the above the present invention is directed to a
variety of embodiments. In at least one embodiment a stent is
provided that provides a more optimized combination of flexibility
and vessel coverage. In some embodiments the stent is balloon
expandable. In some embodiments the stent is self-expandable. In
some embodiments the stent is hybrid expandable.
[0019] In at least one embodiment the stent is provided with a
smooth surface modulation that minimizes tulips.
[0020] In at least one embodiment at least a portion of the stent
is radiopaque.
[0021] In at least one embodiment the stent is at least partially
constructed from a shape memory alloy, polymer and/or other shape
memory material.
[0022] In at least one embodiment the stent is at least partially
constructed from nitinol, stainless steel, or other metal.
[0023] In at least one embodiment the stent is at least partially
constructed from a polymer material and/or is at least partially
coated with one or more polymer materials.
[0024] In at least one embodiment the stent is provided with a
biocompatible coating.
[0025] In at least one embodiment of the invention the stent is
provided with one or more of a variety of patterns or
configurations of interconnected struts, connectors and/or stent
members.
[0026] In some embodiments the stent is provided with a desired
stent pattern by cutting, ablating, shaping or otherwise modifying
a substantially tubular member.
[0027] In some embodiments the stent is provided with a desired
stent pattern by cutting, ablating, shaping or otherwise modifying
a sheet of suitable material. The sheet may then be rolled upon it
itself and the edges of the rolled sheet may be engaged to one
another in an abutting or overlapping configuration.
[0028] In some embodiments the stent is formed from one or more
moulds.
[0029] In at least one embodiment the invention is directed to a
stent comprising a first expansion strut column. The first
expansion strut column is comprised of a plurality of adjacent
first expansion strut pairs, wherein each first expansion strut
pair has a first expansion strut and a second expansion strut. The
first expansion strut column has a plurality of first joining
portions. The first expansion strut is in communication with the
second expansion strut at a first joining portion. The first
expansion strut column has a plurality of second joining portions,
wherein each first expansion strut pair is in communication with an
adjacent first expansion strut pair at each second joining
portion.
[0030] The stent further comprises a second expansion strut column.
The second expansion strut column is comprised of a plurality of
adjacent second expansion strut pairs, wherein each second
expansion strut pair has a first expansion strut and a second
expansion strut. The second expansion strut column has a plurality
of first joining portions. The first expansion strut is in
communication with the second expansion strut at a first joining
portion. The second expansion strut column has a plurality of
second joining portions, wherein each second expansion strut pair
is in communication with an adjacent second expansion strut pair at
each second joining portion.
[0031] The stent further comprises a first connecting strut column.
The first connecting strut column comprises at least one connecting
strut, wherein the at least one connecting strut is comprised of a
first end region, a second end region and an intermediate region
therebetween. The first end region is engaged to a portion of one
of the first expansion strut pairs at a location in closer
proximity to the first expansion strut than to the second expansion
strut. The intermediate region comprises a plurality of bend
portions. At least a portion of the at least one connecting strut
comprises at least one wrap portion, wherein the at least one wrap
portion is at least partially wrapped about at least one of the
first joining portions of at least one of the first expansion strut
column and the second expansion strut column.
[0032] In some embodiments the second end region of the at least
one connecting strut is engaged to a portion of one of the second
expansion strut pairs at a location in closer proximity to the
first expansion strut than to the second expansion strut.
[0033] In some embodiments the second end region is engaged to a
portion of one of the second expansion strut pairs at a location
substantially equal in proximity to the first expansion strut than
to the second expansion strut.
[0034] In some embodiments the stent of claim further comprises a
third expansion strut column and a second connecting strut column.
The third expansion strut column is comprised of a plurality of
adjacent third expansion strut pairs. Each third expansion strut
pair has a first expansion strut and a second expansion strut. The
third expansion strut column has a plurality of first joining
portions. The first expansion strut is in communication with the
second expansion strut at a first joining portion. The second
expansion strut column has a plurality of second joining portions.
Each third expansion strut pair is in communication with an
adjacent third expansion strut pair at each second joining portion.
The second connecting strut column comprises at least one
connecting strut. The at least one connecting strut comprises a
first end region, a second end region and an intermediate region
therebetween. The first end region is engaged to a portion of one
of the second expansion strut pairs at a location in closer
proximity to the first expansion strut than to the second expansion
strut. The intermediate region comprises a plurality of bend
portions. At least a portion of the at least one connecting strut
comprises at least one wrap portion. The at least one wrap portion
is at least partially wrapped about at least one of the second
joining portions of the second expansion strut column and the first
joining portions of the third expansion strut column.
[0035] In some embodiments the second end region of the at least
one connecting strut of the second connecting strut column is
engaged to a portion of one of the third expansion strut pairs at a
location in closer proximity to the first expansion strut than to
the second expansion strut.
[0036] In some embodiments the second end region of the at least
one connecting strut of the second connecting strut column is
engaged to a portion of one of the second expansion strut pairs at
a location substantially equal in proximity to the first expansion
strut than to the second expansion strut.
[0037] In some embodiments the intermediate region of the at least
one connecting strut of the first connecting strut column further
comprises at least one substantially linear portion to at least six
substantially linear portions.
[0038] In some embodiments the intermediate region of the at least
one connecting strut of the second connecting strut column further
comprises at least one substantially linear portion to at least six
substantially linear portions.
[0039] In some embodiments each substantially liner portion
intersects an adjacent substantially linear portion at one of the
bend portions.
[0040] In some embodiments the at least one connecting strut
comprises a single wrap portion, wherein the wrap portion is at
least partially wrapped about at least one of the first joining
portions of the first expansion strut column or one of the first
joining portions of the second expansion strut column.
[0041] In some embodiments the at least one connecting strut
comprises a first wrap portion and a second wrap portion, the first
wrap portion being at least partially wrapped about at least one of
the first joining portions of the first expansion strut column, the
second wrap portion is at least partially wrapped about at least
one of the first joining portions of the second expansion strut
column.
[0042] In some embodiments the at least one wrap portion and the at
least one first joining portion define a slot region, the slot
region having a slot region width, the at least one connecting
strut having a connecting strut width, the slot region width is
less than the connecting strut width.
[0043] In some embodiments the slot region width is about 0.0025
inch and the connecting strut width is about 0.0030 inch.
[0044] In some embodiments the slot region width is about 0.0015
inches and the connecting strut width is 0.002 inch or greater
[0045] In some embodiments the at least one wrap portion is
substantially parallel to the first joining portion about which the
at least one wrap portion is wrapped.
[0046] In some embodiments the at least one wrap portion is an
extension of at least one of the first expansion strut and the
second expansion strut of the first expansion strut pair and/or the
second expansion strut pair.
[0047] In some embodiments the at least one connecting strut of the
first connecting strut column and the at least one connecting strut
of the second connecting strut column has a different shape from
one another.
[0048] In some embodiments the at least one connecting strut of the
first connecting strut column and the at least one connecting strut
of the second connecting strut column has a different length from
one another.
[0049] In some embodiments the at least one connecting strut of the
first connecting strut column and the at least one connecting strut
of the second connecting strut column has substantially the same
length.
[0050] In some embodiments the at least one connecting strut of the
first connecting strut column has a first connecting strut width
and the at least one connecting strut of the second connecting
strut column has a second connecting strut width, the first
connecting strut width and the second connecting strut width are
different from one another.
[0051] In some embodiments the at least one connecting strut of the
first connecting strut column has a first connecting strut width
and the at least one connecting strut of the second connecting
strut column has a second connecting strut width, the first
connecting strut width and the second connecting strut width are
substantially the same.
[0052] In some embodiments the intermediate region of the at least
one connecting strut comprises at least two to at least six bend
portions.
[0053] In some embodiments the first end region of the at least one
connecting strut is engaged to a first expansion strut pair at an
intersection of the first expansion strut and the first joining
portion of the first expansion strut pair.
[0054] In some embodiments the first end region of the at least one
connecting strut is engaged to a first expansion strut pair at an
intersection of the second expansion strut and the first joining
portion of the first expansion strut pair.
[0055] In some embodiments the first end region of the at least one
connecting strut is engaged to the first expansion strut pair at a
location adjacent to an intersection of the first expansion strut
and the first joining portion of the first expansion strut
pair.
[0056] In some embodiments the first end region of the at least one
connecting strut is engaged to the first expansion strut pair at a
location adjacent to an intersection of the second expansion strut
and the first joining portion of the first expansion strut
pair.
[0057] In some embodiments at least a portion of the at least one
connecting strut is substantially parallel to the first expansion
strut of the first expansion strut pair to which the at least one
connecting strut is engaged.
[0058] In some embodiments at least a portion of the at least one
connecting strut is substantially parallel to the first joining
portion of the first expansion strut pair to which the at least one
connecting strut is engaged.
[0059] In some embodiments at least a portion of the at least one
connecting strut is substantially parallel to the second expansion
strut of the first expansion strut pair to which the at least one
connecting strut is engaged.
[0060] In some embodiments the second end region of the at least
one connecting strut is engaged to a second expansion strut pair at
an intersection of the first expansion strut and the first joining
portion of the second expansion strut pair.
[0061] In some embodiments the second end region of the at least
one connecting strut is engaged to a second expansion strut pair at
an intersection of the second expansion strut and the first joining
portion of the first expansion strut pair.
[0062] In some embodiments the second end region of the at least
one connecting strut is engaged to a second expansion strut pair at
a location adjacent to an intersection of the first expansion strut
and the first joining portion of the second expansion strut
pair.
[0063] In some embodiments the second end region of the at least
one connecting strut is engaged to a second expansion strut pair at
a location adjacent to an intersection of the second expansion
strut and the first joining portion of the second expansion strut
pair.
[0064] In some embodiments at least a portion of the at least one
connecting strut is substantially parallel to the first expansion
strut of the second expansion strut pair to which the at least one
connecting strut is engaged.
[0065] In some embodiments at least a portion of the at least one
connecting strut is substantially parallel to the first joining
portion of the second expansion strut pair to which the at least
one connecting strut is engaged.
[0066] In some embodiments at least a portion of the at least one
connecting strut is substantially parallel to the second expansion
strut of the second expansion strut pair to which the at least one
connecting strut is engaged.
[0067] In some embodiments the at least one wrap portion of the at
least one connecting strut extends longitudinally and
circumferentially away from the first expansion strut pair to which
the at least one connecting strut is engaged.
[0068] In some embodiments the at least one wrap portion of the at
least one connecting strut extends longitudinally and
circumferentially away from the second expansion strut pair to
which the at least one connecting strut is engaged.
[0069] In some embodiments at least a portion of the first
expansion strut and at least a portion of the second expansion
strut of each first expansion strut pair are substantially
parallel.
[0070] In some embodiments at least a portion of the first
expansion strut and the at least a portion of the second expansion
strut are not parallel to a longitudinal axis of the stent.
[0071] In some embodiments at least a portion of the first
expansion strut and at least a portion of the second expansion
strut of each second expansion strut pair are substantially
parallel.
[0072] In some embodiments at least a portion of at least one of
the first expansion strut and the second expansion strut of each
first expansion strut pair and/or second expansion strut pair are
substantially parallel to a longitudinal axis of the stent.
[0073] In some embodiments at least one of the first expansion
strut and the second expansion strut of a first expansion strut
pair and/or second expansion strut pair comprise at least one
stepped notch.
[0074] In some embodiments the first end region and/or the second
end region of the at least one connecting strut is engaged to the
at least one stepped notch.
[0075] In some embodiments the first end region and the second end
region of the at least one connecting strut have an ipsilateral
orientation relative to one another.
[0076] In some embodiments the first end region and the second end
region of the at least one connecting strut have a contra-lateral
orientation relative to one another.
[0077] In some embodiments at least two connecting struts of the
first connecting strut column and a first expansion strut pair and
a second expansion strut pair respectively engaged each thereto
form an asymmetrical cell space.
[0078] In some embodiments at least two connecting struts of the
first connecting strut column and a first expansion strut pair and
a second expansion strut pair respectively engaged each thereto
define a cell perimeter about the asymmetrical cell space. In at
least one embodiment the cell perimeter is at least 5 mm in length.
In at least one embodiment the cell perimeter is at least 7 mm in
length. In some embodiments the cell perimeter is about 8 mm or
more.
[0079] In some embodiments the stent comprises at least one
radiopaque marker.
[0080] In some embodiments at least one of the first connecting
strut pairs is configured to retain the at least one radiopaque
marker.
[0081] In some embodiments at least one of the second connecting
strut pairs is configured to retain the at least one radiopaque
marker.
[0082] In some embodiments the at least one radiopaque marker is
selected from at least one member of the group consisting of: at
least one radiopaque rivet, at least one radiopaque band, at least
one radiopaque coating and any combinations thereof.
[0083] In some embodiments at least one of the first expansion
strut and second expansion strut of a first expansion strut pair
having at least one expansion strut bend.
[0084] In some embodiments at least one of the first expansion
strut and second expansion strut of a second expansion strut pair
having at least one expansion strut bend.
[0085] In some embodiments the first end region and/or the second
end region of the at least one connecting strut is engaged to the
at least one expansion strut bend.
[0086] In some embodiments each first expansion strut pair of the
first expansion strut column is both circumferentially and
longitudinally offset relative to the second expansion strut pair
of the second expansion strut column to which the first expansion
strut pair is connected.
[0087] In some embodiments each first expansion strut pair of the
first expansion strut column is only longitudinally offset relative
to the second expansion strut pair of the second expansion strut
column to which the first expansion strut pair is connected.
[0088] In some embodiments the at least one wrap portion of the at
least one connecting strut has at least one substantially linear
section.
[0089] In some embodiments the at least one substantially linear
section of the wrap portion is engaged to a stepped notch of one of
the first expansion strut and second expansion strut.
[0090] In some embodiments the at least one substantially linear
section of the wrap portion and the first expansion strut or second
expansion strut to which it is engaged are substantially
parallel.
[0091] In some embodiments the at least one substantially linear
section of the wrap portion and the first expansion strut or second
expansion strut to which it is engaged define an angle of about 180
to about 135 degrees. In at least one embodiment the angle is about
170 degrees or more.
[0092] In some embodiments the at least one substantially linear
section of the at least one wrap portion extends laterally away
from the stepped notch.
[0093] In some embodiments the at least one wrap portion of the at
least one connecting strut comprises a first substantially linear
section of the at least one connecting strut, the first
substantially linear section extends longitudinally away from the
first expansion strut pair to which it is engaged. A second
substantially linear section of the at least one connecting strut
extends from the first substantially linear section in a direction
toward the first joining portion of the first expansion strut pair.
In at least one embodiment a third section extends from the second
substantially linear section in a direction toward the second
expansion strut pair to which the at least one connecting strut is
engaged. In at least on embodiment the first substantially linear
section is engaged to a stepped notch of one of the first expansion
strut and second expansion strut of the first expansion strut pair.
In at least one embodiment the third substantially linear section
is engaged to a stepped notch of one of the first expansion strut
and second expansion strut of the second expansion strut pair.
[0094] In some embodiments the intermediate portion of the at least
one connecting strut is further comprised of at least two
substantially linear sections, the at least two substantially
linear sections intersecting at an intersection, the intersection
of the at least two substantially linear portions defines a slant
angle. In at least one embodiment the slant angle is obtuse.
[0095] In some embodiments the intermediate portion of the at least
one connecting strut is further comprised of at least two
substantially linear sections, the at least two substantially
linear sections intersecting at an intersection, the intersection
of the at least two substantially linear portions defines a radius
of curvature.
[0096] In some embodiments the stent is configured to deliver at
least one therapeutic agent. In at least one embodiment the at
least one therapeutic agent is one or more coatings. In at least
one embodiment the at least one therapeutic agent is a non-genetic
agent, a genetic agent, cellular material, one or more polymer
coatings, and or any combinations thereof.
[0097] In some embodiments the stent is provided with a plurality
of cavities. In at least on embodiment at least one of the
plurality of cavities extend through at least one of the first
expansion strut, the second expansion strut, the first joining
portion, the second joining portion, and the at least one
connecting strut. In at least one embodiment at least one of the
plurality of cavities extends only partially through at least one
of the first expansion strut, the second expansion strut, the first
joining portion, the second joining portion, and the at least one
connecting strut.
[0098] In some embodiments the invention is directed to a stent
delivery system comprising a stent delivery catheter for delivering
the stent. In at least one embodiment the catheter comprises a
balloon.
[0099] In some embodiments the stent comprises a plurality of
substantially serpentine bands including a first substantially
serpentine band and a second substantially serpentine band. The
first substantially serpentine band and the second substantially
serpentine band are connected by at least one connection member.
The first substantially serpentine band has a plurality of first
end portions and a plurality of second end portions. The second
substantially serpentine band has a plurality of first end portions
and a plurality of second end portions. The at least one connection
member comprising at least one wrap portion, wherein the at least
one wrap portion extends away from one of the plurality first end
potions and wraps around at least a portion of the first end potion
from which it extends. The at least one connection member having a
plurality of bends.
[0100] These and other embodiments which characterize the invention
are pointed out with particularity in the claims annexed hereto and
forming a part hereof. However, for a better understanding of the
invention, its advantages and objectives obtained by its use,
reference should be made to the drawings which form a further part
hereof and the accompanying descriptive matter, in which there is
illustrated and described a embodiments of the invention.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
[0101] A detailed description of the invention is hereafter
described with specific reference being made to the drawings.
[0102] FIG. 1A is a side elevation view of the pre-expansion mode
of an embodiment of the stent of the present invention.
[0103] FIG. 1B is a cross sectional view of an embodiment of the
stent of the present invention.
[0104] FIG. 1C is a longitudinal cross sectional view of an
embodiment of the stent of the present invention.
[0105] FIG. 2A is a scale drawing of the strut pattern of an
embodiment of the stent of the present invention.
[0106] FIG. 2B is an expanded view of a section of the pattern of
FIG. 2A.
[0107] FIG. 3A is a schematic illustration of a pre-expansion mode
of an embodiment of the stent of the present invention.
[0108] FIG. 3B is a schematic illustration of the post-expansion
mode of an embodiment of the stent of the present invention.
[0109] FIG. 4A is a scale drawing including dimensions of an
embodiment of the stent of the present invention.
[0110] FIG. 4B is an enlarged section of the scale drawing of FIG.
4A.
[0111] FIG. 5 is a scale drawing of an embodiment of the stent of
the present invention with a tapered diameter in its post-expansion
mode.
[0112] FIG. 6A is a scale drawing of an embodiment of the stent of
the present invention with reinforcement expansion columns.
[0113] FIG. 6B is a perspective view of the embodiment of FIG.
6A.
[0114] FIG. 7A is a scale drawing of an embodiment of the stent of
the present invention including relief notches at strut joints to
increase flexibility of the joints.
[0115] FIG. 7B is an enlarged region of the embodiment of FIG.
7A.
[0116] FIG. 7C is an enlarged view of a single connecting strut
joining two expansion strut pairs in accordance with the embodiment
of FIG. 7A.
[0117] FIG. 8A is a side elevation view of an embodiment of the
stent of the present invention.
[0118] FIG. 8B is a side elevation view of an embodiment of the
stent of the present invention, shown as if the stent struts and
space there between were transparent.
[0119] FIG. 8C is a scale drawing of an embodiment of the stent of
the present invention.
[0120] FIG. 8D is a variation of the embodiment of the stent of
FIG. 8C.
[0121] FIG. 8E is a perspective view of the embodiment of FIG.
8D.
[0122] FIG. 8F is a drawing illustrating the post-expansion mode of
the stent of the embodiment of FIG. 8D of the present
invention.
[0123] FIG. 8G is an enlarged view of a single connecting strut
joining two expansion strut pairs in accordance with an embodiment
of the present invention.
[0124] FIG. 9A is a side elevation view of an embodiment of the
stent of the present invention.
[0125] FIG. 9B is a perspective view of the embodiment of FIG.
9A.
[0126] FIG. 9C is a scale drawing of the embodiment of FIG. 9A.
[0127] FIG. 9D is an enlarged region of the drawing of FIG. 9C.
[0128] FIG. 9E is a scale drawing of an embodiment of the stent of
the present invention.
[0129] FIG. 9F is a scale drawing of an embodiment of the stent of
the present invention.
[0130] FIG. 9G is an enlarged view of a single connecting strut
joining two expansion strut pairs in accordance with an embodiment
of the present invention.
[0131] FIG. 10A is a drawing of an alternate geometry of connecting
struts and joining struts in accord with the present invention.
[0132] FIG. 10B is a drawing of an alternate geometry of connecting
struts and joining struts in accord with the present invention.
[0133] FIG. 10C is a drawing of an alternate geometry of connecting
struts and joining struts in accord with the present invention.
[0134] FIG. 10D is a drawing of an alternate geometry of connecting
struts and joining struts in accord with the present invention.
[0135] FIG. 10F is a drawing of an alternate geometry of connecting
struts and joining struts in accord with the present invention.
[0136] FIG. 10F is a drawing of an alternate geometry of connecting
struts and joining struts in accord with the present invention.
[0137] FIG. 11 is a delivery balloon catheter, illustrating a
method of deliver of a stent in accord with the present
invention.
[0138] FIG. 12 is a partial side view of an embodiment of the
invention.
[0139] FIG. 13 is a perspective view of an embodiment of the
invention.
[0140] FIG. 14 is a side view of the embodiment shown in FIG.
13.
[0141] FIG. 15 is a side view of the embodiment shown in FIG.
13.
[0142] FIG. 16 is a perspective view of an embodiment of the
invention.
[0143] FIG. 17 is a side view of the embodiment shown in FIG.
16.
[0144] FIG. 18 is a side view of the embodiment shown in FIGS. 16
and 17.
[0145] FIG. 19 is a side view of an embodiment of the
invention.
[0146] FIG. 20 is a side view of an embodiment of the
invention.
[0147] FIG. 21 is a side view of an embodiment of the
invention.
[0148] FIG. 22 is a side view of an embodiment of the
invention.
[0149] FIG. 23 is a side view of an embodiment of the
invention.
[0150] FIG. 24 is a side view of an embodiment of the
invention.
[0151] FIG. 25 is a perspective view of an embodiment of the
invention.
[0152] FIG. 26 is a side view of an embodiment of the
invention.
[0153] FIG. 27 is a side view of an embodiment of the
invention.
[0154] FIG. 28 is a perspective view of an embodiment of the
invention.
[0155] FIG. 29 is a side view of an embodiment of the
invention.
[0156] FIG. 30 is a perspective view of an embodiment of the
invention.
[0157] FIG. 31 is a side view of the embodiment of the invention
shown in FIG. 30.
[0158] FIG. 32 is a perspective view of an embodiment of the
invention.
[0159] FIG. 33 is a side view of an embodiment of the
invention.
[0160] FIG. 34 is a side view of an embodiment of the
invention.
[0161] FIG. 35A is a side view of an embodiment of the
invention.
[0162] FIG. 35B is a side view of an embodiment of the
invention.
[0163] FIG. 36A is an enlarged view of a portion of the embodiment
shown in FIG. 35A.
[0164] FIG. 36B is an enlarged view of a portion of the embodiment
shown in FIG. 35B
[0165] FIG. 37 is a perspective view of an embodiment of the
invention.
[0166] FIG. 38 is a side view of an embodiment of the
invention.
[0167] FIG. 39 is a side view of a configuration of the embodiment
shown in FIG. 38.
[0168] FIG. 40 is a partial side view of an alternative
configuration of the embodiment shown in FIG. 38.
[0169] FIG. 41 is a perspective view of an embodiment of the
invention.
[0170] FIG. 42 is a side view of the embodiment shown in FIG.
41.
[0171] FIG. 43 is an enlarged side view of the embodiment shown in
FIG. 41.
[0172] FIG. 44 is a perspective view of an embodiment of the
invention.
[0173] FIG. 45 is a side view of the embodiment shown in FIG.
44.
[0174] FIG. 46 is a partial side view of a configuration of the
embodiment shown in FIG. 44.
[0175] FIG. 47 is a partial side view of a configuration of the
embodiment shown in FIG. 44.
[0176] FIG. 48 is a perspective view of an embodiment of the
invention.
[0177] FIG. 49 is a side view of the embodiment shown in FIG.
48.
[0178] FIG. 50 is an enlarged side view of the embodiment shown in
FIG. 48
[0179] FIG. 51 is a partial side view of a configuration of the
embodiment shown in FIG. 48.
[0180] FIG. 52 is a perspective view of an embodiment of the
invention.
[0181] FIG. 53 is a side view of an embodiment of the
invention.
[0182] FIG. 54 is a side view of an embodiment of the
invention.
[0183] FIG. 55 is a side view of an embodiment of the
invention.
[0184] FIG. 56 is a side view of an embodiment of the
invention.
[0185] FIG. 57 is a side view of an embodiment of the
invention.
[0186] FIG. 58 is a side view of an embodiment of the
invention.
[0187] FIG. 59 is a side view of an embodiment of the
invention.
[0188] FIG. 60 is a side view of an embodiment of the
invention.
[0189] FIG. 61 is an enlarged sectional view of the embodiment
shown in FIG. 61.
[0190] FIG. 62 is a side view of an embodiment of the
invention.
[0191] FIG. 63 is an enlarged sectional view of the embodiment
shown in FIG. 62.
[0192] FIG. 64 is a side view of an embodiment of the
invention.
[0193] FIG. 65 is an enlarged sectional view of the embodiment
shown in FIG. 64
[0194] FIG. 66 is a partial side view of an embodiment of the
invention.
[0195] FIG. 67 is a partial side view of an embodiment of the
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0196] While this invention may be embodied in many different
forms, there are described in detail herein embodiments of the
invention. This description is an exemplification of the principles
of the invention and is not intended to limit the invention to the
particular embodiments illustrated.
[0197] For the purposes of this disclosure, like reference numerals
in the figures shall refer to like features unless otherwise
indicated.
[0198] An embodiment of the present invention is shown in FIGS. 1A,
1B, 1C, 2A and 2B. Referring to FIG. 1A, an elongate hollow tubular
stent 10 in an unexpanded state is shown.
[0199] It is understood that a stent may have a variety of
expansion states which provide the stent with a variety of
different stent diameters that will vary depending on the specific
expansion state the stent is in. The term "unexpanded" as used
herein refers to one or more of such configurations and/or
diameters prior to implantation of the stent into a body lumen.
[0200] A proximal end 12 and a distal end 14 define a longitudinal
length 16 of stent 10. The longitudinal length 16 of the stent 10
can be as long as 100 mm or longer. A proximal opening 18 and a
distal opening 20 connect to an inner lumen 22 of stent 10. Stent
10 can be a single piece, without any seams or welding joints or
may include multiple pieces.
[0201] Stent 10 is constructed of two to fifty or more expansion
columns or rings 24 connected together by interspersed connecting
strut columns 26. The first column on the proximal end 12 and the
last column on the distal end 14 of stent 10 are expansion columns
24.
[0202] Expansion columns 24 are formed from a series of expansion
struts 28, and joining struts 30. Expansion struts 28 are elongate
members arranged so that they extend at least in part in the
direction of the longitudinal axis of stent 10. When an outward
external force is applied to stent 10 from the inside by an
expansion balloon or other means, or when the stent 10 is caused to
self-expand, the expansion struts 28 are reoriented such that they
extend in a more circumferential direction, i.e. along the surface
of cylindrical stent 10 and perpendicular to its longitudinal axis.
Reorientation of expansion struts 28 causes stent 10 to have an
expanded circumference and diameter. In the embodiment shown in
FIG. 1A, expansion struts 28 of unexpanded stent 10 are seen to
extend substantially parallel to the longitudinal axis of stent
10.
[0203] Expansion struts 28 are joined together by joining struts 30
to form a plurality of expansion strut pairs 32. Expansion strut
pairs have a closed end 34 and an open end 36. Additional joining
struts 30 join together expansion struts 28 of adjacent expansion
strut pairs 32, such that expansion struts 28 are joined
alternately at their proximal and distal ends to adjacent expansion
struts 28 to form expansion columns 24. Each expansion column 24
contains a plurality, typically eight to twenty, twenty to sixty,
or more of expansion struts 28. Expansion columns are preferably
continuous unbroken ring structures extending around the
circumference of the stent 10; however, broken structures in which
individual struts or pieces of struts are removed from an otherwise
continuous expansion column 24 can also be used.
[0204] Connecting struts 38 connect adjacent expansion columns 24
forming a series of interspersed connecting strut columns 26 each
extending around the circumference of stent 10. Each connecting
strut 38 joins a pair of expansion struts 28 in an expansion column
24 to an adjacent pair of expansion struts 28 in an adjacent
expansion column 24. For stent 10 of FIG. 1A, the ratio of
expansion struts 28 in an expansion column 24 to connecting struts
38 in a connecting strut column 26 is two to one; however, this
ratio in general can be X to 1 where X is greater or less than two.
Other ratios may also be utilized. Furthermore, since the stent 10
of FIG. 1A begins with an expansion column 24 on the proximal end
12 and ends with an expansion column 24 on the distal end 14, if
there are n expansion columns 24 with m expansion struts 28 per
column, there will be m-1 connecting strut columns 26, and n(m-1)/2
connecting struts 38.
[0205] The reduced number of connecting struts 38 in each
connecting strut column 26, as compared to expansion struts 28 in
each expansion column 24, allows stent 10 to be longitudinally
flexibility. Longitudinal flexibility can be further increased by
using a narrow width connecting strut, providing additional
flexibility and suppleness to the stent as it is navigated around
turns in a natural blood vessel. In some embodiments at least one
portion of one or more the connecting struts 38 may have a width
different than that of one or more adjacent portions.
[0206] At least a portion of the open spaces between struts in
stent 10 form asymmetrical cell spaces 40. A cell space or
geometric cell is an empty region on the surface of stent 10,
completely surrounded by one or a combination of stent struts,
including expansion struts 28, connecting struts 38, or joining
struts 30. Asymmetrical cell spaces 40 are cell spaces which have
no geometrical symmetry i.e. no rotation, reflection, combination
rotation and reflection or other symmetry. Asymmetrical cell spaces
40 have an asymmetrical geometric configuration.
[0207] Asymmetrical cell spaces 40 in FIG. 1A are surrounded by a
first expansion strut pair 32 in a first expansion column 24, a
first connecting strut 38, a second expansion strut pair 32 in an
adjacent expansion column 24, a first joining strut 30, a second
connecting strut 38, and a second joining strut 30. Furthermore,
expansion strut pairs 32 of asymmetrical cell space 40 may be
circumferentially offset i.e. have longitudinal axes that are not
collinear and have their open ends 36 facing each other. The space
between two expansion struts of an expansion strut pair 32 is known
as a loop slot 42.
[0208] FIG. 1B shows inner lumen 22, radius 44 and stent wall 46 of
stent 10. Stent wall 46 is comprised of stent struts including
expansion struts 28, connecting struts 38 and joining struts
30.
[0209] FIG. 1C shows, proximal end 12, distal end 14, longitudinal
length 16, inner lumen 22, and stent wall 46 of stent 10. Inner
lumen 22 is surrounded by stent wall 46 which forms the cylindrical
surface of stent 10.
[0210] Referring now to FIGS. 2A and 2B, joining struts 30 of stent
10 are seen to extend at an angle to the expansion struts 28,
forming a narrow angle 48 with one expansion strut 28 in an
expansion strut pair 32 and a wide angle 50 with the other
expansion strut 28 of an expansion strut pair 32. Narrow angle 48
is less than ninety degrees, while wide angle 50 is greater than
ninety degrees. Joining struts 30 extend both longitudinally along
the longitudinal axis of stent 10 and circumferentially, along the
surface of the stent 10 perpendicular to its longitudinal axis.
[0211] Expansion strut spacing 52 between adjacent expansion struts
28 in a given expansion column 24 are uniform in stent 10 of FIGS.
2A and 2B; however, non-uniform spacings can also be used.
Expansion strut spacings 52 can be varied, for example, spacings 52
between adjacent expansion struts 28 in an expansion column 24 can
alternate between a narrow and a wide spacings. Additionally,
spacings 52 in a single expansion column 24 can differ from other
spacings 52 in other columns 24.
[0212] It is noted that varying expansion strut spacings 52 which
form the loop slots 42 results in variable loop slot widths.
Furthermore, the longitudinal axis of the loop slots 42 need not be
collinear or even parallel with the longitudinal axis of loop slots
42 of an adjacent expansion column 24. FIGS. 2A and 2B show an
arrangement of expansion struts 28 such that collinear, parallel
adjacent loop slots 42 are formed, but non-collinear and
non-parallel loop slots 42 can also be used.
[0213] Additionally the shape of loop slots 42 need not be the same
among loop slots of a single or multiple expansion columns 24. The
shape of loop slots 42 can be altered by changing the orientation
or physical dimensions of the expansion struts 28 and/or joining
struts 30 which connect expansion struts 28 of expansion strut
pairs 32 defining the boundaries of loop slots 42.
[0214] Connecting struts 38 couple adjacent expansion columns 24,
by connecting the distal end of an expansion strut pair in one
expansion column 24 to the proximal end of an adjacent expansion
strut pair 32 in a second expansion column 24. Connecting struts 38
of FIGS. 2A and 2B are formed from two linear sections, a first
linear section 54 being joined at its distal end to a second linear
section 56 at its proximal end to form a first slant angle 58.
[0215] The first linear section 54 of a connecting strut 38 is
joined to expansion strut 28 at the point where joining strut 30
makes narrow angle 48 with expansion strut 28. First linear section
54 extends substantially collinear to joining strut 30 continuing
the line of joining strut 30 into the space between expansion
columns 24. The distal end of the first linear section 54 is joined
to the proximal end of the second linear section 56 forming slant
angle 58. Second linear section 56 extends substantially parallel
to expansion struts 28 connecting at its distal end to joining
strut 30 in an adjacent expansion column 24. The distal end of
second linear section 56 attaches to expansion strut 28 at the
point where joining strut 30 makes narrow angle 48 with expansion
strut 28. Further, joining strut 30 can have a second slant angle
with a width that can be the same or different from the width of
the first slant angle.
[0216] FIGS. 2A and 2B show connecting struts 38 and joining struts
30 slanted relative to the longitudinal axis of stent 10, with the
circumferential direction of the slanted struts alternating from
column to adjacent column. Circumferential direction refers to the
handedness with which the slanted struts wind about the surface of
the stent 10. The circumferential direction of the slant of
connecting strut first linear sections 54 in a connecting strut
column 26 is opposite the circumferential direction of the slant of
connecting strut first linear sections 54 in an adjacent connecting
strut column 26. Similarly, the circumferential direction of the
slant of joining struts 30 in an expansion column 24 is opposite
the circumferential direction of the slant of joining struts 30 in
an adjacent expansion column 24. Alternating circumferential slant
directions of connecting struts 38 and joining struts 30 prevents
axial warping of stent 10 during deliver and expansion. Other
non-alternating slant direction patterns can also be used for
connecting struts 38 or joining struts 30 or both.
[0217] FIGS. 3A and 3B show a schematic illustration of a stent
design according to the present invention in an unexpanded and
expanded state respectively. The design is depicted as a flat
projection, as if stent 10 were cut lengthwise parallel to its
longitudinal axis and flattened out. The connecting struts 38
comprise first and second linear sections 54 and 56 forming slant
angle 58 at pivot point 60. An asymmetrical cell space 40 is formed
by expansion strut pairs 32, connecting struts 38 and joining
struts 30. Multiple interlocking asymmetrical cell spaces 40 make
up the design pattern.
[0218] As the stent is expanded, see FIG. 3B, the expansion strut
pairs 32 spread apart at their open ends 36, shortening the length
of expansion struts 28 along the longitudinal axis of the
cylindrical stent. The longitudinal shortening of expansion struts
28 during expansion is countered by the longitudinal lengthening of
connecting struts 38. The widening of slant angle 58 during
expansion straightens connecting struts 38 and lengthens the
distance between the coupled expansion strut pairs 32. The widening
of the slant angle of connecting struts 38 substantially
compensates for the longitudinal shortening of expansion struts 28.
Thus, the stent has substantially constant unexpanded and expanded
longitudinal lengths.
[0219] When the stent is expanded, each expansion column 24 becomes
circumferentially stretched, enlarging the space between struts.
The interlinking of expansion columns 24 by connecting struts 38
that have been straightened through the expansion process gives the
stent 10 a high radial support strength. The entire stent 10 when
expanded is unitized into a continuous chain mesh of stretched
expansion columns 24 and connecting strut columns 26 forming an
asymmetrical interlocking cell geometry which resists collapse both
axially and radially. When the stent is expanded it has increased
rigidity and fatigue tolerance.
[0220] In addition, efficient bending and straightening of
connecting struts 38 at pivot points 60 allows increased
longitudinal flexibility of the stent. For the stent to bend
longitudinally, at least some of connecting struts 38 are forced to
bend in their tangent plane. The tangent plane of a specific
connecting strut 38 refers to the plane substantially tangent to
the cylindrical surface of the stent at that connecting strut 38.
The width of connecting struts 38 can be twice as wide as a
thickness. In some embodiments a one-to-one ratio may be provided
for, however other configurations and ratios of thickness to width
may be utilized. However, pivot points 60 in connecting struts 38
provide connecting struts 38 a flexible joint about which to more
easily bend increasing longitudinal flexibility of the stent.
[0221] Referring to FIGS. 4A and 4B, an embodiment of the stent 10
of the present invention is shown. In this embodiment stent 10 has
a length 16 of 33.25 mm and an uncrimped and unexpanded
circumference 88 of 5.26 mm. Fifteen expansion columns 24 are
interspersed with connecting strut columns 26. Each expansion
column 24 is comprised of twelve expansion struts 28 joined
alternately at their proximal and distal ends by joining struts 30
forming six expansion strut pairs 32. Expansion struts 28 are
aligned parallel to the longitudinal axis of cylindrical stent 10.
Joining struts 30 form a narrow angle 48 and a wide angle 50 with
the respective expansion struts 28 of expansion strut pairs 32.
Adjacent expansion columns 24 employ alternating circumferential
slant directions of joining struts 30.
[0222] In this embodiment expansion strut width 62 is 0.20 mm,
expansion strut length 64 is 1.51 mm, and connecting strut width 66
is 0.13 mm. Distance 68 from the outer edge of a first expansion
strut 28 to the outer edge of a second adjacent expansion strut 28
in the same expansion column 24 is 0.64 mm, leaving a loop slot
width 70 of 0.24 mm.
[0223] In this embodiment, connecting struts 38 is comprised of a
slanted first linear section 54 joined to a second linear section
56 at a slant angle 58. First linear section 54 is slightly longer
than second linear section 56 and is attached at its proximal end
to an expansion strut 28 in an expansion column 24. The attachment
of the proximal end of first linear section 54 to expansion strut
28 is at the point where joining strut 30 makes narrow angle 48
with expansion strut 28. First linear section 54 extends
substantially collinear to joining strut 30 attaching at its distal
end to the proximal end of second linear section 56 to form slant
angle 58. Second linear section 56 extends substantially collinear
to expansion struts 28, attaching at its distal end to an expansion
strut 28 in an adjacent expansion column 24. The attachment occurs
at the point where expansion strut 28 forms narrow angle 48 with
joining strut 30. Joining struts 30 and connecting strut first
linear sections 54 slant in alternating circumferential directions
from column to adjacent column.
[0224] The joining of connecting struts 38 and expansion struts 28
at the point where narrow angle 48 is formed aids smooth delivery
of stent 10 by streamlining the surface of the unexpanded stent and
minimizing possible catching points. Bare delivery of stent 10 to
the target lesion in a vessel will thus result in minimal snagging
or catching as it is navigated through turns and curvatures in the
vessel. Stent 10 behaves like a flexible, tubular sled as it is
moved forward or backward in the vessel on the delivery catheter,
sliding through tortuous vessels and over irregular bumps caused by
atherosclerotic plaques inside the vessel lumen.
[0225] When fully expanded the stent 10 of FIGS. 4A and 4B has an
internal diameter of up to 5.0 mm or more, while maintaining an
acceptable radial strength and fatigue tolerance. The crimped stent
outer diameter can be as small as 1.0 mm or less depending on the
condition of the underlying delivery balloon profile; a small
crimped outer diameter is especially important if stent delivery is
to be attempted without predilation of the target site. When the
stent is optimally crimped over the delivery balloon, the surface
of the crimped stent is smooth allowing for no snagging of the
stent struts during either forward or backward movement through a
vessel.
[0226] FIG. 5 shows an embodiment of the present invention in which
the stent 10 in its expanded form has a gradual taper from proximal
end 12 to distal end 14. The shaded segments 72, 74, 76, 78, 80, 82
and 84 of expansion struts 28 represent regions of expansion struts
28 to be removed. Removal of the shaded segments 72, 74, 76, 78,
80, 82 and 84 provides stent 10 with a gradual taper when expanded
with distal end 14 having a smaller expanded diameter than proximal
end 12. The degree of shortening of the expanded diameter of the
stent 10 at a given expansion column 24 will be proportional to the
length of the removed segment 72, 74, 76, 78, 80, 82, or 84 at that
expansion column 24. In the expanded stent 10 the shortened
expansion struts 28 will have a shortened component along the
circumference of the stent resulting in a shortened circumference
and diameter. The tapered diameter portion can be positioned
anywhere along the length of stent 10, and the tapering can be made
more or less gradual by removing appropriately larger or smaller
portions of the expansion struts 28 in a given expansion column
24.
[0227] Tapering may be especially important in long stents, longer
than 12 mm, since tapering of blood vessels is often more
pronounced over longer lengths. Thus in some embodiments it is
desirable to have a stent with a tapered expanded diameter.
[0228] Another way to achieve a tapered expanded stent is to change
the stiffness of the stent struts, expansion struts, connecting
struts or joining struts such that the stiffness of the struts
varies along the length of the stent. The stiffness of the struts
can be changed by altering length, width or thickness, adding
additional stiffening material, using a chemical or mechanical
means to alter the physical properties of the stent material, or
applying one or a series of elastic elements about the stent.
[0229] Along with the use of a tapered diameter stent, a matching
tapered balloon catheter would ideally be made for delivery and
deployment of the tapered diameter stent. The method of using a
tapered matching balloon catheter with a tapered diameter stent is
within the scope of the present invention.
[0230] Using a tapered balloon to expand a non-tapered stent will
also achieve a tapered expanded stent; however, since no metal is
removed from the stent, the stent is tapered as a result of
incomplete expansion. The stent will therefore have increased metal
fraction at the tapered end resulting in increased risk of acute
thrombosis. Metal fraction is the proportion of the surface of the
expanded stent covered by the stent strut material. Shortening the
expansion struts as shown in FIG. 5 allows for a tapered expanded
stent with substantially constant metal fraction along its
length.
[0231] Another embodiment of the present invention shown in FIGS.
6A and 6B has multiple re-enforcement expansion columns 86 placed
along the length of the stent 10. The re-enforcement columns 86 are
placed along the stent length to provide additional localized
radial strength and rigidity to stent 10. Additional strength and
rigidity are especially important at the ends of the stent to
prevent deformation of the stent both during delivery and after
placement. During delivery the stent ends can catch on the vessel
wall possibly deforming the unexpanded stent and altering its
expansion characteristics. After the stent has been placed it is
important that the stent ends are rigid so that they set firmly
against the vessel wall; otherwise, during a subsequent catheter
procedure, the catheter or guidewire can catch on the stent ends
pulling the stent away from the vessel wall and possibly damaging
and/or blocking the vessel.
[0232] A variation of the embodiment of stent 10 depicted in FIGS.
6A and 6B has a length 16 of 20.70 mm and an uncrimped and
unexpanded circumference 88 of 5.26 mm. The stent 10 may comprise
six expansion columns 24 and three re-enforcement expansion columns
86, each comprising respectively of twelve expansion struts 28 or
re-enforcement expansion struts 90. The re-enforcement expansion
columns 86 are positioned one at either end, and one along the
length of the stent 10.
[0233] In some embodiments the expansion strut width 62 is 0.15 mm,
re-enforcement expansion strut width 92 is 0.20 mm, and the
connecting strut width 66 is 0.10 mm. The narrow angle 48 formed by
joining strut 30 and expansion strut 28 is 75 degrees, and the
narrow angle 94 formed by re-enforcement joining strut 96 and
re-enforcement expansion strut 90 is 60 degrees.
[0234] Other arrangements of re-enforcement expansion columns 86,
such as providing re-enforcement expansion columns 86 only on the
ends of the stent, only on one end, or at multiple locations
throughout the length of the stent can also be used and fall within
the scope of the present invention. A taper can also be programmed
into the re-enforced stent 10 by shortening expansion struts 28 and
re-enforcement expansion struts 90 in appropriate expansion columns
24 and 86.
[0235] Yet another embodiment of the present invention, shown in
the FIGS. 7A, 7B and 7C, is similar to the embodiment shown in
FIGS. 6A and 6B but has the added feature of relief notches 98 and
100. A relief notch is a notch where metal has been removed from a
strut, usually at a joint where multiple struts are connected.
Relief notches increase flexibility of a strut or joint by creating
a thinned, narrow region along the strut or joint. Relief notch 98
is formed at the joint formed between first linear section 54 of
connecting strut 38 and expansion strut 28. Relief notch 100 is
formed at the joint between second linear section 56 of connecting
strut 38 and expansion strut 28. The positioning of the relief
notches gives added flexibility to the unexpanded stent and
prevents warping at the joints when the stent is expanded. This
results in a smooth surface modulation to the expanded stent frame.
Relief notches can be placed at other joints and can be included in
any of the previously mentioned embodiments.
[0236] FIGS. 8A and 8B show a side elevation view of a variation of
an embodiment of the stent of the present invention. In this
embodiment a four piece slanted connecting strut 38 is used to
couple the corner of an expansion strut pair 32 in one expansion
column 24 to the joining strut 30 of a circumferentially offset
expansion strut pair 32 in an adjacent expansion column 24. The
expansion struts 28, joining struts 30, expansion columns 24,
re-enforcement expansion struts 90, re-enforcement joining struts
96, and re-enforcement expansion columns 86 are substantially
similar to the fourth embodiment of FIG. 6A. Connecting struts 38
in connecting strut columns 26, however, have an altered geometry
and connectivity, described in more detail below.
[0237] FIG. 8A shows only the stent struts on the front half of the
stent surface. The stent struts on the rear half of the stent
surface are not shown. The stent appears as it would if the stent
struts and space there between were opaque. FIG. 8B shows all stent
struts from both the front and rear halves. The stent appears as it
would if the stent struts and the space there between were
transparent.
[0238] Another variation of the embodiment shown in FIGS. 8A and 8B
is depicted in FIG. 8C wherein the stent 10 is provided with twelve
expansion columns 24, four re-enforcement expansion columns 86, and
fifteen connecting strut columns 26. In this variation, the stent
10 has a length 16 of 31.96 mm, and an unexpanded circumference 88
of 5.26 mm.
[0239] Connecting struts 38 shown in an enlarged view in FIG. 8G
are made up of four linear sections, a proximal end section 162,
first and second intermediate sections 164 and 166 respectively and
a distal end section 168 forming three slant angles 170, 172 and
174. The proximal end of proximal section 162 is attached to a
corner 176 of an expansion strut pair 32 of an expansion column 24.
Corner 176 is formed where joining strut 30 makes narrow angle 48
with expansion strut 28. A second corner 178 of expansion strut 32
is formed where joining strut 30 makes wide angle 50 with expansion
strut 28. Corners 176 and 178 can have an angular shape formed by
joining linear expansion struts 28 and joining struts 30, or
preferably corners 176 and 178 are rounded to remove sharp edges
and provide increased flexibility. Additionally rounded corners
provide stent 10 with greater expandability and reduce stress in
the stent strut material at the corners in the expanded stent.
[0240] Proximal end section 162 of connecting strut 38 extends from
corner 176 and is attached at its distal end to first intermediate
section 164 forming slant angle 170. First intermediate section 164
extends from proximal end section 162 such that first intermediate
section 164 is parallel to expansion struts 28 and is connected at
its distal end to the proximal end of second intermediate section
166 forming slant angle 172.
[0241] Second intermediate section 166 extends in a slanted
orientation relative to the longitudinal axis of stent 10,
extending both longitudinally along and circumferentially about
stent 10. Preferably, second intermediate section 166 is parallel
to joining strut 30 of the circumferentially offset expansion strut
pair 32 in adjacent expansion column 24.
[0242] Second intermediate section 166 attaches at its distal end
to the proximal end of distal end section 168 forming slant angle
174. Distal end section 168 extends from second intermediate
section 166 attaching at its distal end to joining strut 30 of
circumferentially offset expansion strut pair 32 of adjacent
expansion column 24. The attachment is at a point intermediate
corners 176 and 178, where joining strut 30 forms narrow angle 48
and wide angle 50 respectively with expansion struts 28.
[0243] The connection point of distal end section 168 to joining
strut 30 is closer to corner 176 than corner 178. Preferably the
connection point is one to two or more expansion strut widths from
corner 176. Offsetting the connection point of distal end section
168 to joining strut 30 from corner 176 to a point intermediate
corner 176 and corner 178 reduces warping of the expanded stent 10,
resulting in a smooth surface modulation and reduced risk of
thrombosis. Additionally, this design provides a longer total
straightened length of connecting strut 38, which further reduces
foreshortening of stent 10 during expansion.
[0244] Another variation of the stent described above is shown in
an unexpanded form in FIGS. 8D, 8E and in an expanded form in FIG.
8F comprises a stent 10 with six expansion columns 24, two
re-enforcement expansion columns 86, and seven connecting strut
columns 26. In this variation, the stent 10 has a length 16 of
15.04 mm, and an unexpanded circumference 88 of 5.26 mm. The stent
design 10 is substantially similar to the design of the embodiment
of FIG. 8C with a reduced number of expansion columns,
re-enforcement expansion columns, and connecting strut columns.
[0245] FIG. 8F illustrates a portion of the expanded stent 10.
After expansion of stent 10 by balloon or other means, the
expansion struts 28 are spread apart circumferentially, increasing
the separation at the open end 36 of expansion strut pairs 32
resulting in an increase in the circumference of the stent 10. The
spreading of the expansion struts 28 causes a longitudinal
shortening of the expansion columns 24, which is compensated by a
straightening of the connecting struts 38. During the expansion
process, the slant angles 170, 172 and 174 widen straightening the
connecting struts 38, and causing an increase in the separation
distance between adjacent expansion columns 24. The asymmetrical
interlocking cell geometry of the expanded stent is illustrated in
FIG. 8F.
[0246] FIGS. 9A, 9B, 9C, 9D, 9E, 9F and 9G illustrate another
embodiment of the stent of the present invention. In this
embodiment a three piece slanted connecting strut 38 is used to
couple the joining strut 30 of an expansion strut pair 32 in one
expansion column 24 to the joining strut 30 of a circumferentially
offset expansion strut pair 32 in an adjacent expansion column 24.
The joints between segments of connecting strut 38 are curved
forming a smooth rounded shape. The expansion struts 28, joining
struts 30, expansion columns 24, re-enforcement expansion struts
90, re-enforcement joining struts 96, and re-enforcement expansion
columns 86 are substantially similar to the fourth embodiment of
FIG. 8A. Connecting struts 38 in connecting strut columns 26,
however, have an altered geometry and connectivity, described in
more detail below.
[0247] In the present embodiment shown in FIGS. 9A, 9B and 9C the
stent comprises eight expansion columns 24, three re-enforcement
expansion columns 86, and ten connecting strut columns 26. In this
variation, the stent 10 has a length 16 of 20.32 mm.
[0248] Relief notches 204 are utilized at the joints between
re-enforcement expansion struts 90 and re-enforcement joining
struts 96 in the re-enforcement expansion columns 86 at the stent
proximal end 12 and distal end 14. Relief notches 204 reduce the
width of the joints between re-enforcement expansion struts 90 and
re-enforcement joining struts 96, which reduces stress in the metal
at the joints during and after expansion of the stent. Relief
notches 204 are particularly important at the stent ends since the
stent ends are especially susceptible to warping during and after
expansion. In some embodiments relief notches 204 reduce the joint
widths, such that the joint widths are substantially the same as
the thickness of stent wall 46 (see FIGS. 1B and 1C).
[0249] Connecting struts 38 shown in an enlarged view in FIG. 9D
are made up of three linear sections, a proximal end section 194,
an intermediate section 196 and a distal end section 198 forming
two slant angles 200, 202. The connecting struts 38 have wide radii
of curvature at the joints between connecting strut sections 194,
196 and 198.
[0250] The shape of connecting strut 38 is thus curved or wavy
rather than jagged and angular.
[0251] The slant angles 200 and 202 are defined by linearly
extrapolating proximal end section 194, intermediate section 196
and distal end section 198, as shown by the dotted lines in FIG.
9D.
[0252] FIG. 9E shows a variation of the connecting strut design of
an embodiment of the invention. The connecting strut 38 of FIG. 9E
has smaller radii of curvature at the joints between proximal end
section 194, intermediate section 196 and distal end section 198.
Connecting strut 38 of FIG. 9E is thus more jagged and angular than
that of FIG. 9D.
[0253] Referring to the connecting struts 38 of FIGS. 9D and 9E,
the proximal end of proximal section 194 is attached to joining
strut 30 of expansion strut pair 32 intermediate corners 176 and
178. Proximal end section 194 of connecting strut 38 extends from
joining strut 30 and is attached at its distal end to intermediate
section 196 forming slant angle 200. Intermediate section 196
extends from proximal end section 194 in a slanted orientation
relative to the longitudinal axis of stent 10, extending both
longitudinally along and circumferentially about stent 10.
Intermediate section 196 is preferably parallel to joining struts
30 of coupled expansion strut pairs 32.
[0254] Intermediate section 196 is connected at its distal end to
the proximal end of distal end section 198 forming slant angle 202.
Distal end section 198 extends from second intermediate section 196
attaching at its distal end to joining strut 30 of
circumferentially offset expansion strut pair 32 of adjacent
expansion column 24. The attachment is at a point intermediate
corners 176 and 178, where joining strut 30 forms narrow angle 48
and wide angle 50 respectively with expansion struts 28.
[0255] The connection point of proximal end section 194 and distal
end section 198 to joining struts 30 is closer to corner 176 than
corner 178. Preferably the connection point is one to two or more
expansion strut widths from corner 176. Offsetting the connection
point of distal end section 198 to joining strut 30 from corner 176
to a point intermediate corner 176 and corner 178 reduces warping
of the expanded stent 10, resulting in a smooth surface modulation
and reduced risk of thrombosis. Additionally, this design provides
a longer total straightened length of connecting strut 38, which
further reduces foreshortening of stent 10 during expansion.
[0256] The connecting strut 38 of at least one embodiment has one
hundred and eighty degree rotational symmetry about its center. The
symmetry of the connecting strut 38 does not, however, result in a
symmetrical cell space as the width of loop slots 42 connected in
each cell space are different. Adjacent loop slots 42 in each
expansion column have alternating narrow and wide widths,
preserving the asymmetry of the cell spaces. Introduction of one or
many symmetrical cell spaces can be achieved in this design e.g. by
providing uniform loop slot width to loop slots in adjacent
expansion columns 24 contained in the same cell space. Additionally
completely non-uniform cell space patterns utilizing symmetric or
asymmetric cell spaces can be achieved e.g. by providing
non-uniform variations in the widths of loop slots 42.
[0257] In another embodiment shown in FIG. 9F, the stent 10 is
shown in an unexpanded form and comprises six expansion columns 24,
three re-enforcement expansion columns 86, and eight connecting
strut columns 26. In this variation, the stent 10 has a length 16
of 16.00 mm, and an unexpanded circumference 88 of 5.26 mm. The
stent design 10 is substantially similar to the design of the
embodiment of FIGS. 9A, 9B and 9C with a reduced number of
expansion columns 24 and connecting strut columns 26.
[0258] In the embodiment shown in FIG. 9G comprises a stent 10 with
twelve expansion columns 24, four re-enforcement expansion columns
86, and fifteen connecting strut columns 26. In this variation, the
stent 10 has a length 16 of 30.01 mm, and an unexpanded
circumference 88 of 5.26 mm. The stent design 10 is substantially
similar to the design of the embodiment of FIGS. 9A, 9B and 9C with
an increased number of expansion columns 24 re-enforcement
expansion columns 86 and connecting strut columns 26.
[0259] FIGS. 10A, 10B, 10C, 10D, 10E and 10F illustrate some
examples of alternate connecting strut designs which can be used in
any of the previously discussed embodiments. FIG. 10A shows a
rounded loop connecting strut 38 which joins two circumferentially
offset expansion strut pairs 32 in adjacent expansion columns.
Expansion struts 28 in each expansion strut pair 32 are joined by
adjoining strut 30. Joining struts 30 are slanted such as to form a
narrow angle 48 and a wide angle 50 with the expansion struts 28
they connect. The rounded loop connecting strut 38 connects
expansion struts 28 at the point where narrow angle 48 is formed
between expansion struts 28 and joining struts 30. The slopes of
the rounded connecting strut 38 at its proximal end 102 and distal
end 104 substantially match the slopes of the joining struts 30
connecting the pairs of expansion struts 28. The rounded loop
connecting strut 38 thus blends smoothly into the joining struts
30. Additionally the rounded loop connecting strut 38 has a first
radius of curvature 106 and a second radius of curvature 108.
[0260] In the embodiment shown in FIG. 10B a rounded loop
connecting strut 38 joins two circumferentially offset expansion
strut pairs 32 in adjacent expansion columns. Expansion struts 28
in each expansion strut pair 32 are joined by a joining strut 30.
Joining struts 30 are at right angles to the expansion struts 28
they connect. The rounded loop connecting strut 38 connects to
expansion struts 28 at the same point as joining struts 30. The
rounded connecting strut 38 has a first radius of curvature 106 and
a second radius of curvature 108 such that it connects
circumferentially offset expansion strut pairs 32.
[0261] In the embodiment of FIG. 10C connecting strut 38 joins two
circumferentially offset expansion strut pairs 32 in adjacent
expansion columns. Expansion struts 28 in each expansion strut pair
32 are joined by adjoining strut 30. Joining struts 30 are slanted
such as to form a narrow angle 48 and a wide angle 50 with the
expansion struts 28 they connect. The connecting strut 38 connects
expansion struts 28 at the point where narrow angle 48 is formed
between expansion strut 28 and joining strut 30.
[0262] The connecting strut 38 is made up of three linear sections
110, 112, and 114 forming two slant angles 116 and 118. The
proximal end of section 110 is attached to expansion strut 28 at
the point where joining strut 30 forms narrow angle 48 with
expansion strut 28. Section 110 extends substantially collinear to
joining strut 30 and is attached at its distal end to intermediate
section 112 forming slant angle 116.
[0263] Intermediate section 112 extends at an angle to section 110
such that intermediate section 112 is substantially parallel to
expansion struts 28 and is connected at its distal end to the
proximal end of distal section 114 forming slant angle 118. Distal
section 114 extends at an angle such that it is substantially
collinear to joining strut 30 of the adjacent expansion strut pair
32. Distal section 114 attaches at its distal end to expansion
strut 28 of the adjacent expansion strut pair 32, at the point
where joining strut 30 forms narrow angle 48 with expansion strut
28.
[0264] In the embodiment of FIGS. 10D and 10E a connecting strut 38
joins two circumferentially offset expansion strut pairs 32 in
adjacent expansion columns. Expansion struts 28 in each expansion
strut pair 32 are joined by a joining strut 30. Joining struts 30
are at right angles to the expansion struts 28 they connect. The
connecting strut 38 connects to expansion struts 28 at the same
point as joining struts 30.
[0265] The connecting struts 38 of FIGS. 10D and 10E are made up of
multiple connecting strut sections connected end to end to form a
jagged connecting strut 38 with multiple slant angles, coupling
expansion strut pair 32 to adjacent expansion strut pair 32. The
connecting strut of FIG. 10D is made up of three connecting strut
sections, a proximal section 120, an intermediate section 122 and a
distal section 124 defining two slant angles 126 and 128, while the
connecting strut of FIG. 10E comprises of four connecting strut
sections, a proximal section 130, intermediate sections 132 and
134, and a distal section 136 defining three slant angles 138, 140
and 142. In addition, connecting strut section 134 can be modified
by replacing connecting strut section 136 by the dotted connecting
strut section 144 to give another possible geometry of connecting
struts 38.
[0266] In the embodiment of FIG. 10F connecting strut 38 joins two
circumferentially offset expansion strut pairs 32 in adjacent
expansion columns. Expansion struts 28 in each expansion strut pair
32 are joined by a joining strut 30. Joining struts 30 are slanted
such as to form a narrow angle 48 and a wide angle 50 with the
expansion struts 28 they connect.
[0267] Connecting strut 38 is made up of four linear sections, a
proximal end section 180, first and second intermediate sections
182 and 184 respectively and a distal end section 186 forming three
slant angles 188, 190 and 192. The proximal end of section 180 is
attached to corner 176 at the point where joining strut 30 forms
narrow angle 48 with expansion strut 28. Proximal end section 180
extends at an angle to joining strut 30 and is attached at its
distal end to first intermediate section 182 forming slant angle
188. First intermediate section 182 extends at an angle to proximal
end section 180 such that first intermediate section 182 is
substantially parallel to expansion struts 28 and is connected at
its distal end to the proximal end of second intermediate section
184 forming slant angle 190. Second intermediate section 184 is
substantially longer than the first intermediate section 182.
Second intermediate section 184 extends at an angle such that it is
substantially collinear to joining strut 30 of the adjacent
expansion strut pair 32. Second intermediate section 184 attaches
at its distal end to the proximal end of distal end section 186
forming slant angle 192. Distal end section 186 extends in a
slightly sloping orientation relative to expansion struts 28,
attaching to corner 176 of expansion strut pair 32 where joining
strut 30 forms narrow angle 48 with expansion strut 28. Relief
notches 206 are formed at the joint between distal end segment 186
of connecting strut 38 and corner 176 of expansion strut pair 32 to
increase flexibility of the unexpanded stent and prevent warping
when the stent is expanded.
[0268] One skilled in the art will recognize that there are many
possible arrangements of connecting struts and joining struts
consistent with the present invention; the above examples are not
intended to be an exhaustive list. In particular, it is noted that
(a) connecting strut sections need not be linear but may contain
one or many radii of curvature, (b) connecting strut sections may
each have a different longitudinal axis, (c) the joint between
connecting strut sections need not be jagged or sharp, but rather
can be smooth containing one or multiple radii of curvature, and
(d) relief notches may be present at any of the strut joints.
[0269] The stent of the present invention is ideally suited for
application in coronary vessels although versatility in the stent
design allows for applications in non-coronary vessels, the aorta,
and nonvascular tubular body organs.
[0270] Typical coronary vascular stents have expanded diameters
that range from 2.5 to 5.0 mm. However, a stent with high radial
strength and fatigue tolerance that expands to a 5.0 mm diameter
may have unacceptably high stent metal fraction when used in
smaller diameter vessels. If the stent metal fraction is high, the
chances of acute thrombosis and restenosis potential will increase.
Even with the same metal fraction a smaller caliber vessel is more
likely than a larger one to have a high rate of thrombosis. It is,
therefore, preferred to have at least two different categories of
stents for coronary application, for example, small vessels stents
for use in vessels with diameters from 2.5 mm to 3.0 mm, and large
vessel stents for use in vessels with diameters from 3.0 mm to 5.0
mm. Thus, both small vessels and large vessels when treated with
the appropriate sized stent will contain stents of similar
idealized metal fraction.
[0271] The stent of the present invention can be made using a
CAM-driven laser cutting system to cut the stent pattern from a
stainless steel tube. The rough-cut stent is preferably
electro-polished to remove surface imperfections and sharp edges.
Other methods of fabricating the stent can also be used such as,
water/laser-jet, EDM, photo-electric etching technology, or other
methods. Any suitable material can be used for the stent including
other metals and polymers so long as they provide the essential
structural strength, flexibility, biocompatibility and
expandability.
[0272] In some embodiments at least a portion of the stent is
plated or otherwise provided with a radiopaque material such as
metals including gold, platinum, tantalum or other suitable metal.
It is preferred to provide one or both ends of the stent with a
radiopaque material by localized plating or other mechanisms;
however, the entire stent or other regions can also be plated or
otherwise provided with radiopaque material. When plating both
ends, one to three or more expansion columns on each end of the
stent are plated to mark the ends of the stent so they can be
identified under fluoroscopy during the stenting procedure. By
plating the stent only at the ends, interference of the radiopaque
plating material with performance characteristics or surface
modulation of the stent frame is minimized. Additionally the amount
of plating material required is reduced, lowering the material cost
of the stent.
[0273] In some embodiments one or more expansion struts or other
portions of the stent are provided with one or more radiopaque
fasteners such as a crimped sleeve of radiopaque material, a rivet
of radiopaque material or other device(s).
[0274] After plating, the stent is cleaned, typically with
detergent, saline and ultrasonic means that are well-known in the
art. The stents are then inspected for quality control, assembled
with the delivery balloon catheter, and properly packaged, labeled,
and sterilized.
[0275] Stent 10 can be marketed as stand alone or as a pre-mounted
delivery balloon catheter assembly as shown in FIG. 11. Referring
to FIG. 11, the stent 10 is crimped over a folded balloon 146 at
the distal end 148 of a delivery balloon catheter assembly 150. The
assembly 150 includes a proximal end adapter 152, a catheter shaft
154, a balloon channel 156, a guidewire channel 158, a balloon 146,
and a guidewire 160. Balloon 146 can be tapered, curved, or both
tapered and curved from a proximal end to a distal end in the
expanded state. Additionally stent 10 can be non-tapered or tapered
in the expanded state.
[0276] Typically the guidewire 160 is inserted into the vein or
artery and advanced to the target site. The catheter shaft 154 is
then forwarded over the guidewire 160 to position the stent 10 and
balloon 146 into position at the target site. Once in position the
balloon 146 is inflated through the balloon channel 156 to expand
the stent 10 from a crimped to an expanded state. In the expanded
state, the stent 10 provides the desired scaffolding support to the
vessel. Once the stent 10 has been expanded, the balloon 146 is
deflated and the catheter shaft 154, balloon 146, and guidewire 160
are withdrawn from the patient.
[0277] The stent of the present invention can be made as short as
less than 10 mm in length or as long as 100 mm or more. If long
stents are to be used, however, matching length or preferably
slightly longer delivery catheter balloons will typically be needed
to expand the stents into their deployed positions. Long stents,
depending on the target vessel, may require curved long balloons,
tapered long balloons or curved and tapered long balloons for
deployment. Curved and/or tapered balloons which match the natural
curve and taper of a blood vessel reduce stress on the blood vessel
during and after stent deployment. This is especially important in
many coronary applications which involve stenting in curved and
tapered coronary vessels. The use of such curved and/or tapered
balloons is within the scope of the present invention.
[0278] In some embodiments of the invention such as those depicted
in FIGS. 1A, 2A-8E, 8G, 10A-10F and 12-67, the stent 10 may be
characterized as having a first expansion strut column 24a
comprised of a plurality of adjacent first expansion strut pairs
32a, each of which in turn have a first expansion strut 28a and a
second expansion strut 28b. The first expansion strut column 24a
further comprises a plurality of first joining portions or struts
30a. The first expansion strut 28a is in communication with the
second expansion strut 28b via the first joining portion 30a. The
first expansion strut column 24a also comprises a plurality of
second joining portions 30b, each first expansion strut pair 32a is
in communication with an adjacent first expansion strut pair 32a
via a second joining portion 30b.
[0279] Adjacent to the first expansion strut column 24a is a second
expansion strut column 24b that is comprised of a plurality of
adjacent second expansion strut pairs 32b, wherein each second
expansion strut pair comprises a first expansion strut 28a and a
second expansion strut 28b. The second expansion strut column
further comprises a plurality of first joining portions 30a,
wherein the first expansion strut 28a is in communication with the
second expansion strut 28b at a first joining portion 30a. The
second expansion strut column further comprises a plurality of
second joining portions 30b. Each second expansion strut pair 32b
is in communication with an adjacent second expansion strut pair
32b via a second joining portion 30b;
[0280] Between the first expansion strut column 24a and the second
expansion strut column 24b is positioned a first connecting strut
column 26a. The first connecting strut column 26a comprises at
least one connecting strut 38. The connecting strut 38, comprises a
first end region 302, a second end region 304 and an intermediate
region 306 therebetween.
[0281] The first end region 302 extends from a portion of one of
the first expansion strut pairs 32a at a location in closer
proximity to the first expansion strut 28a than to the second
expansion strut 28b. The second end region 304 extends from a
portion of one of the second expansion strut pairs 32b. In some
embodiments, such as for example in the embodiment shown in FIG.
34, the second end region 304 is engaged to a portion of the second
expansion strut pair 32b at a location substantially equal in
proximity to the first expansion strut 28a and the second expansion
strut 28b. In other embodiments, such as for example those depicted
in FIGS. 12-33 and 35A-67, the second end region 304 is engaged to
a portion of the second expansion strut pair 32b at a location in
closer proximity to the first expansion strut 28a than to the
second expansion strut 28b.
[0282] At least one of the connecting struts comprise a wrap
portion 308. The wrap portion 308 is at least partially wrapped
about at least one first joining portions 30a of either or both the
first expansion strut column 24a and the second expansion strut
column 24b. The wrap portion 308 of the connector 38 may comprise
one or more portions of the connector or alternatively the entire
connector 38 may be characterize as a wrap portion 308 or one or
more interconnected wrap portions 308.
[0283] In the embodiments shown in FIGS. 12-67 the intermediate
region 306 further comprises at least two bend portions 310a and
310b.
[0284] In some embodiments, such as those illustrated in FIGS.
16-18 and 21-67 the connecting struts 38 each have a connecting
strut width 66. The wrap portion 308 of one or more of the
connecting struts 38 and at least one first joining portion of
either or both of the first expansion strut column 24a and the
second expansion strut column 24b define a slot region 320, wherein
the slot region 320 defines a slot region width 322, the slot
region width 322 being no greater than the connecting strut width
66. In some embodiments the slot region width 22 is the point at
which the connecting strut 38 and the first or second joining
portion 30a or 30b respectively are at their closest proximity but
not touching.
[0285] In some embodiments such as are depicted in FIGS. 34-65 the
wrap portion 308 of at least one of the connecting struts 38 is
characterized as an extension 314 of one or both of the first
expansion strut 28a and the second expansion strut 28b of either or
both the first expansion strut column 24a and the second expansion
strut column 24b. At least a portion of the extension 314 runs
parallel to at least a portion of the first joining portion 30a of
at least one of the first expansion strut column 24a and second
expansion strut column 24b.
[0286] In various embodiments of the invention depicted in FIGS.
12-67 the stent 10 is provided with expansion strut columns 24 that
may be characterized as substantially serpentine bands wherein the
first expansion strut column 24a is a first substantially
serpentine band and the second expansion strut column is a second
substantially serpentine band. The first substantially serpentine
band 24a and the second substantially serpentine band 24b are
connected by at least one connecting member 38. The at least one
connecting member has a connecting member width 66. The first
substantially serpentine band 24a has a plurality of first end
portions 30a and a plurality of second end portions 30b. The second
substantially serpentine band 24b has a plurality of first end
portions 30a and a plurality of second end portions 30b. The at
least one connection member 38 and at least one first end portion
30a of at least one of the first substantially serpentine band 24a
and the second serpentine band 24b forming a slot region 320, the
slot region having a slot region width 322, the slot region width
322 is no greater than the connection member width 66.
[0287] In some embodiments the at least one connection member 38
comprises the at least one wrap portion 308. The at least one wrap
portion extends away from at least one of the plurality first end
potions 326 and wraps around at least a portion of the first end
potion 326 from which it extends.
[0288] In some embodiments, such as for example those depicted in
FIGS. 12, 22, 35, 36, 57, 58, 64 and 65, the stent 10 is provided
with at least two distinctly different configurations of connecting
struts or members 38. Connectors 38 of different configurations may
be utilized in the same connecting strut column or different
connecting strut columns 26a and 26b respectively, as is shown.
Connectors 38 of different configurations may have different
shapes, lengths, components, widths, angular orientations,
compositions, etc., from one another.
[0289] A first connector configuration 350 of FIG. 12 has an
intermediate region 306 having three bend portions indicated at:
310a, 310b, and 310c. While the intermediate region 306 of a second
connector configuration 354 comprises five bend portions indicated
at: 310a, 310b, 310c, 310d and 310e.
[0290] In the embodiment of FIG. 12, the various configurations 350
and 354 of connecting struts or connectors 38 includes a wrap
portion 308 that extends longitudinally and circumferentially away
from the strut pair 32a of the first expansion strut column 24a to
engage a strut pair 32b of the second expansion strut column 24b.
As is shown, in some embodiments the first end region 302 of the
connector 38 is engaged to the strut pair 32a at an intersection
352 of the first expansion strut 28a and a first joining strut or
portion 30a, while the second end region 304 of the connector is
engaged to the strut pair 32b at a point on a first joining strut
30a of the second expansion strut column. It must be noted however,
that different engagement configurations between the strut pairs
32a and 32b and the first end region 302 and the second end region
304, respectively, may be utilized.
[0291] In the embodiments shown in FIGS. 13-15, the first expansion
strut column 24a of the stent 10 is made of a plurality of adjacent
first expansion struts 28a and second expansion struts 28b
connected by a plurality of first joining struts 30a to form
adjacent first strut pairs 32a. A joining strut 30a forms a first
intersection 356 where the first joining strut 30a joins a first
expansion strut 28a and a second intersection 358 is formed where
the first joining strut 30a joins a second expansion strut 28b of
the first expansion strut pair 32a.
[0292] The first and second expansion struts 28a and 28b in a first
expansion strut column 24a are aligned so that at least a portion
of the first and second expansion struts 28a and 28b are parallel
to each other. However, one or more portions of either or both of
the first and second expansion struts 28a and 28b may not be
parallel to the longitudinal axis 17 of the stent 10 and/or to the
adjacent companion first or second expansion strut 28a and 28b.
[0293] In some embodiments, the one or both of the first expansion
strut 28a and the second expansion strut 28b of a given expansion
strut pair 32a and/or 32b may include a stepped notch 360 on a
distal or proximal end of the respective first or second expansion
strut 28a and/or 28b. At least a portion of the stepped notch 360
is an engagement site where the first end region 302 or second end
region 304 of a connector 38 is engaged to the given strut pair 32a
and/or 32b.
[0294] The connector 38 extends between the stepped notch 360 of a
first strut pair 32a of a first expansion strut column 24a to a
stepped notch 360 of a longitudinally adjacent second strut pair
32b of a second expansion strut column 24b. In the embodiment shown
in FIGS. 13-15 the notch 360 of the first strut pair 32a has a
contra-lateral position relative to the notch 360 of the second
strut pair 32b to which a given connector 38 is in communication
therebetween.
[0295] In at least one embodiment, as best shown in FIG. 13, some
first and/or second expansion struts 28a and/or 28b are provided
with no stepped notches 360. While other struts 28a and/or 28b are
provided with at least two stepped notches 360, indicated and 360a
and 360b. While connectors 38 are depicted as extending from either
or both of the proximal most notch and/or distal most notch, it
should be recognized that a connector 38 may engage a given first
or second strut pair at any point desired.
[0296] The connectors 38 shown in FIGS. 13-15 are provided with
four bend portions 310a, 310b, 310c and 310d.
[0297] As a result of the unique shape of the connectors 38 and the
longitudinally offset arrangement of adjacent first expansion strut
pairs 32a and second expansion strut pairs 32b, as the wrap portion
308 of each connector 38 wraps about the first joining strut 30a of
the first expansion strut pair 24a it also wraps about the first
joining strut 30a of the second expansion strut pair 24b.
[0298] A pair of circumferentially adjacent connectors 38 and
longitudinally adjacent first expansion strut pair 32a and second
expansion strut pair 32b form an asymmetrical cell space 40 as
described above. In at least one embodiment, an example of which is
shown in FIG. 15 the connectors 38 and the expansion strut pairs
32a and 32b which define the cell space 40 have a cell perimeter of
at least 5 mm, and may be at least 7 mm or more. In at least one
embodiment the perimeter of the cell space 40 is about 8.19 mm.
[0299] Turning to the embodiments depicted in FIGS. 16-18 the first
and second expansion struts 28a and 28b may be configured in any of
the variety of manners describe in relation to the embodiments of
FIGS. 13-15.
[0300] As to the connectors 38 however, in the embodiments depicted
in FIGS. 16-18 the connectors 38 of the present embodiments are
provided with at least 6 bend portions 310a, 310b, 310c, 310d, 310e
and 310f.
[0301] Each bend portion, like all bend portions described herein
may act as a pivot point about which the connector may bend and or
flex as the stent 10 is expanded or reduced in diameter.
[0302] The first end region 302 of the connector 38 is engaged to
the first expansion strut pair 32a and the second end region 304 of
the connector 38 is engaged to an adjacent second expansion strut
pair 32b in an ipsilateral arrangement as best shown in FIGS. 17
and 18.
[0303] Like the embodiments shown in FIGS. 13-18 the embodiments
shown in FIGS. 19 and 20 are also provided with stepped notches 360
in one or more first expansion strut 28a and/or second expansion
strut 28b. Furthermore, in the embodiments depicted in FIGS. 19 and
20 one or more of the first expansion struts 28a and/or second
expansion struts 28b are provided with one or more expansion strut
bend portions 312. As is shown, each first expansion strut pair 32a
and second expansion strut pair 32b is provided with a first
expansion strut 28a having at least one bend portion 312 and a
second expansion strut 28b having at least one stepped notch 360.
This arrangement of alternating struts having at least one bend
portion 312 and struts having at least one stepped notch 360,
results in a stent 10 having first and second struts 28a and 28b
with no portion thereof being parallel to the longitudinal axis 17
of the stent 10. However, in the embodiments shown in FIGS. 19 and
20, the distal most expansion strut column and the proximal most
expansion strut column of the stent 10 may be provided with
expansion strut pairs wherein at least a portion of one or more
expansion struts 28a and/or 28b is parallel to the longitudinal
axis 17.
[0304] The wrap portion 308 of each connector 38 wraps about both
the first joining strut 30a of the first expansion strut pair 32a
as well as the first joining strut 30a of the second expansion
strut pair 32b as it extends between the first expansion strut pair
32a and the second expansion strut pair 32b.
[0305] The first end region 302 of the connector 38 is engaged to
one of the first expansion struts 28a or second expansion struts
28b of the first expansion strut column 24a. The second end region
304 of the connector 38 is engaged to one of the first expansion
struts 28a or second expansion struts 28b of the second expansion
strut column 24b. The connectors 38 have end regions 302 and 304
that are contra-laterally engaged to opposing first expansion strut
pairs 32a and second expansion strut pairs 32b.
[0306] In the embodiment shown in FIG. 19 the intermediate region
306 of each connector comprises at least four bend portions 310a,
310b, 310c and 310d. In the embodiment shown in FIG. 20, at least
some of the connectors 38 are provided with intermediate regions
having at least 5 bend portions 310a, 310b, 310c, 310d and
310e.
[0307] As indicated above, any of the stent 10 described herein may
be provided with one or more radiopaque markers, coatings or other
mechanisms or devices for improving the radiopacity of at least a
portion of the stent. In FIG. 20 one or more of a first expansion
strut 28a or second expansion strut 28b defines a radiopaque marker
housing 362. A radiopaque marker housing 362 may be positioned
anywhere on the stent including but not limited to a mid portion of
the stent, one or more areas of the stent adjacent thereto, on or
both end regions of the stent, etc. For example, in the embodiment
shown, a pair of housings are provided with each housing 362
positioned near the proximal end 12 and the distal end 14 of the
stent 10. A radiopaque marker 363 of any type known in the art,
including rivets, bands, etc may be positioned at least partially
within, on, and/or about the housing 362.
[0308] Turning now to the embodiment of FIG. 21, in the embodiment
shown, each first expansion strut column 24a comprises first
expansion strut pairs 32a which are comprised of a first expansion
strut 28a and a second expansion strut 28b, wherein one of the
first expansion strut 28a or the second expansion strut 28b is
parallel to the longitudinal axis 17 of the stent 10. Similarly
each second expansion strut column 24b comprises second expansion
strut pairs 32b which are comprised of a first expansion strut 28a
and a second expansion strut 28b, wherein one of the first
expansion strut 28a or the second expansion strut 28b is parallel
to the longitudinal axis 17 of the stent 10. Each first expansion
strut 28a and each second expansion strut 28b of a first and second
expansion strut pair 32a and 32b is respectively joined by a first
joining strut.
[0309] Where the first expansion strut 28a of a given first or
second expansion strut column is parallel to the longitudinal axis
17 of the stent 10, each first expansion strut 28a is also parallel
to every other first expansion strut 28a of the first or second
expansion strut column of which it is a member. Similarly, where
the second expansion strut 28b of a given first or second expansion
strut column is parallel to the longitudinal axis 17 of the stent
10, each second expansion strut 28b is also parallel to every other
second expansion strut 28b of the first or second expansion strut
column of which it is a member.
[0310] In the embodiment shown in FIG. 21 at least a portion of
each first expansion strut 28a of each expansion strut pair 32a and
32b forms an acute angle with the second expansion strut 28b. One
of the first expansion strut 28a or second expansion strut 28b of
each expansion strut pair 32a and 32b has at least one expansion
strut bend 312.
[0311] Connectors 38 extend between a first expansion strut pair
32a and an adjacent second expansion strut pair 32b, wherein the
first end region 302 of the connector 38 is engaged to the at least
one expansion strut bend of the first expansion strut pair 32a and
the second end region 304 of the connector 38 is engaged to the at
least one expansion strut bend of the second expansion strut pair
32b in an ipsilateral configuration.
[0312] The wrap portion 308 of each connector 38 wraps about only
one of either the first joining strut 30a of the respective first
expansion strut pair 32a and the second expansion strut pair 32b to
which an individual connector 38 is engaged.
[0313] As is shown in the embodiment depicted in FIG. 21 the wrap
portion 308 and the joining strut 30a or 30b form the slot region
320 as previously described. The slot region width 322, is no
greater than the connection member width 66.
[0314] In the embodiment shown in FIG. 21 the intermediate region
306 of each connector 308 comprises at least three bend portions
310a, 310b and 310c.
[0315] In the embodiment shown in FIG. 22, a first connecting strut
column 26a is comprised of connectors 38 of a substantially similar
configuration to those described in the embodiments shown in FIGS.
13-15. The connectors 28 of the first connecting strut column 26a
join longitudinally adjacent first expansion strut pairs 32a and
second expansion strut pairs 32b in the contra-lateral orientation
shown.
[0316] In addition to the connectors 38 of the first connecting
strut column 26a, the stent 10 is also provided with a second
connecting strut column 26b wherein each connector 38 of the second
connecting strut column 26b join circumferentially and
longitudinally offset second expansion strut pairs 32a and third
expansion strut pairs 32c in the ipsilateral orientation shown. The
connectors 38 of the second connecting strut column 26b are
substantially similar in configuration to the connectors described
in relation to the embodiments depicted in FIG. 21.
[0317] In other embodiments of the invention shown in FIGS. 23 and
24 the stent is provided with connectors 38, wherein each connector
38 comprises a first wrap portion 308a and a second wrap portion
308b. The first wrap portion 308a of the connector 38 wraps at
least partially about the first joining strut 30a of the first
strut pair 32a to which the first end region 302 of the connector
is engaged.
[0318] The second wrap portion 308b of the connector 38 wraps at
least partially about the first joining strut 30a of the second
strut pair 32b to which the second end region 304 of the connector
38 is engaged.
[0319] The first end region 302 of each connector 38 is engaged to
one of the first expansion strut 28a or the second expansion strut
28b of a first expansion strut pair 32a and the second end region
304 of each connector 38 is engaged to one of the first expansion
strut or the second expansion strut of a second expansion strut
pair 32b in a contra-lateral orientation.
[0320] Each connector 38 in the embodiments shown in FIGS. 23 and
24 comprise at least four bend portions 310a, 310b, 310c and
310d.
[0321] In the embodiment shown in FIG. 23 the connectors 38 have a
more elongated configuration when compared to those shown in the
embodiment of FIG. 24. In FIG. 24 at least a portion of the
intermediate region 306 of each connector 38 is substantially
parallel to the longitudinal axis 17 of the stent 10, whereas in
the embodiment of FIG. 23 each connectors 38 is provided with an
intermediate portion 306 of which at least a portion forms an acute
angle 370 with the longitudinal axis 17 of the stent 10 as well as
an obtuse angle 372 with the longitudinal axis 17 of the stent
10.
[0322] In the various embodiments shown in FIGS. 25-33, the stent
10 is comprised of alternating first and second expansion strut
columns 24a and 24b, with the first and second expansion strut
columns being in communication with one another via a connecting
strut column 26a. The first expansion strut column 24a includes
first expansion strut pairs 32a wherein at least one or both of the
first expansion strut 28a and the second expansion strut 28b have
one or more stepped notches 360 as previously described.
[0323] In the various embodiments shown in FIGS. 25-33 each of the
connectors 38 include a first end region 302 which is engaged to
and extends from the stepped notch 360 of the first expansion strut
pair 24a and a second end region 304 which is engaged to and
extends from a stepped notch 360 of the second expansion strut
pair.
[0324] In some embodiments, such as for example those shown in
FIGS. 25, 26, 30-31, the first end region 302 and the second end
region 304 are engaged respectively to a first expansion strut pair
32a and a second expansion strut pair 32b in a contra-lateral
configuration. In other embodiments, for example those shown in
FIGS. 27-29 and 32-33, the first end region 302 and the second end
region 304 are engaged respectively to a first expansion strut pair
32a and a second expansion strut pair 32b in an ipsilateral
configuration.
[0325] In the various embodiments shown in FIGS. 25-33, the
connectors 38 are provided with a connector width 66 and the first
and second expansion struts 28a and 28b which comprise the first
and second expansion strut pairs 32a and 32b are provided with an
expansion strut width 62. In many of the embodiments described
herein, including those depicted in FIGS. 25-33, the expansion
strut width 62 is greater than the connector width 66. It is noted
however that in some embodiments the stent 10 may be provided with
connectors 38 wherein at least a portion of a connector width 66 is
equal to or greater than at least a portion of the expansion strut
width 62.
[0326] In some embodiments such as those depicted in FIGS. 42, 49
and 53 within a given expansion strut column there may be
differences in the width of the expansion struts relative to one
another. Similarly within a given connecting strut column the width
of the connectors may vary from one another.
[0327] In the embodiments shown in FIGS. 25-31 the connectors 38
share the common featured of having one or both of first end region
302 and second end region 304 of each connector extend in a
substantially linear manner from the stepped notch 360 of either
the first expansion strut 28a or the second expansion strut 28b of
a respective first expansion strut pair 32a or second expansion
strut pair 32b. In some embodiments a portion of the connector 38
adjacent to one or both of the end regions 302 and 304 may be
substantially parallel to the expansion strut to which it is
respectively engaged. In other embodiments one or more portions of
the connector 38 adjacent to the end regions 302 and 304 may define
an angle of about 180 degrees to about 135 degrees with the
respective expansion strut 28a or 28b to which they are each
respectively engaged. In some embodiment the angle thusly defined
is about 135 degrees or greater.
[0328] As is clear from the various embodiments shown, the
intermediate region 306 of the connectors 38 depicted in the
embodiments of FIGS. 25-33 may be provided with a diverse number of
bend portions. For example in the embodiment shown in FIGS. 25-29
the intermediate portion 306 comprises two bend portions 310a and
310b. In the embodiments shown in FIGS. 30 and 31 the intermediate
portion comprises at least four bend portions 310a, 310b, 310c and
310d.
[0329] In the embodiments shown in FIGS. 32 and 33 the connectors
38 differ from those shown in FIGS. 25-31 in that one or both of
the first end region 302 and the second end region 304 of each
connector 38 extends laterally away from the stepped notch 360 of
either the first expansion strut 28a or the second expansion strut
28b of a respective first expansion strut pair 32a or second
expansion strut pair 32b to which they are engaged.
[0330] In the embodiments shown in FIGS. 25-33 one or both of the
end regions 302 and 304 may be substantially linear as previously
described above. However, in some of the embodiments shown such as
including the embodiments of FIGS. 28-33 a connector 38 may
initially extend longitudinally and/or circumferentially away from
the expansion strut pair to which it is engaged and then change
course back toward the strut pair before engaging the adjacent
strut pair of the adjacent strut pair column. The combination of an
end region 302 and/or 304 which extend away from the expansion
strut pair to which it or they are engaged and an intermediate
region 306 of which at least a portion returns back toward the
expansion strut pair to which the connector is engaged forms a
distinctive wrap portion 308 of the connector 38 which wraps about
the first joining strut 30a of at least one of the first expansion
strut pair 32a and second expansion strut pair 32b
respectively.
[0331] In some embodiments described herein the intermediate
section 306 of a given connector 38 may be further comprised of one
or more substantially linear sections, such as for example: a first
substantially linear section 382, a second substantially linear
section 384 and/or a third substantially linear section 386
depicted in FIGS. 26 and 27. A given connector may have only a
single substantially linear section or any plurality of
substantially linear sections. More typically however a connector
may have between two and eight substantially linear sections. Some
example embodiments having one or more substantially linear
sections are shown in FIGS. 25-33. Other embodiments described
herein may also include one or more substantially linear
sections.
[0332] As is shown in various embodiments, and most clearly
depicted in FIGS. 26 and 31, where a connector 38 has intersecting
substantially linear sections, such as for example a first and a
second substantially linear sections 382 and 384, the intersection
of the substantially linear sections is comprised of at least one
bend or curved portion 310a-f. The intersection of the
substantially linear sections may define a slant angle 58 as
previously described. In some embodiments the intersections of the
substantially linear sections may define a radius of curvature,
which may vary between different intersections of different
sections of the connector.
[0333] In some embodiments, some examples of which are shown in the
embodiments of FIGS. 26 and 31, at least two substantially linear
sections, such as the first and third substantially linear sections
382 and 386, respectively, are substantially parallel to one
another. In some embodiments, an example of which is shown in FIG.
29, the first substantially linear section 382 and the second
substantially linear section 384 define a slant angle 58 which is
obtuse, and the second substantially linear section 384 and the
third substantially linear section 386 define a slant angle 58 that
is also obtuse.
[0334] Where a connector is comprised of one or more substantially
linear sections as described, the individual sections may be
substantially the same or different from one another in their
various physical characteristics, such as length, width, thickness,
cross-sectional shape, composition, angular orientation to one
another, etc. For example in the embodiment shown in FIG. 27, each
of the first, second and third substantially linear sections 382,
384 and 386 respectively, have a different length.
[0335] While in many of the embodiments described thus far, the end
regions 302 and 304 are often respectively engaged to expansion
strut pairs wherein the engagement of the end region is closer in
proximity to one expansion strut verses the other of the given
expansion strut pair, in some embodiments, such as for example the
embodiment shown in FIG. 34, at least one of the end regions, in
this example the second end region 304 is engaged to a second
expansion strut pair 32b at a location substantially equivalent in
proximity to the first expansion strut 28a and the second expansion
strut 28b. As a result of this connector configuration, the wrap
portion 308 of the connector wraps only the first joining strut 30a
of the first strut pair 32a.
[0336] In some embodiments of the invention, some examples of which
are depicted in the embodiments of FIGS. 35A-65, the connectors 38
may be characterized as comprising a first wrap portion 308a, a
second wrap portion 308b, and at least one substantially linear
section 382 therebetween.
[0337] In the various embodiments shown in FIGS. 35A-65, the first
end region 302 of a connector 38 is engaged to one of the first
expansion strut 28a or the second expansion strut 28b, at or
adjacent to a stepped notch 360, of a first strut pair 32a. The
second end region 302 of a connector 38 is engaged to one of the
first expansion strut 28a or the second expansion strut 28b, at or
adjacent to a stepped notch 360, of a second expansion strut pair
32b.
[0338] The first wrap portion 308a extends from the first end
region 302 and wraps at least partially around the first joining
strut 28a of the first expansion strut pair 32a. The wrap portion
is substantially parallel to the first joining strut 28a. The first
wrap portion 308a and the first joining strut 28a define a slot
region 320, wherein the slot region 320 defines a slot region width
322, the slot region width 322 is no greater than the connecting
strut width 66.
[0339] The second wrap portion 308b extends from the second end
region 304 and wraps at least partially around the first joining
strut 28a of the second expansion strut pair 32b. The wrap portion
is substantially parallel to the first joining strut 28a. The
second wrap portion 308b and the first joining strut 28a define a
slot region 320, wherein the slot region 320 defines a slot region
width 322, the slot region width 322 is no greater than the
connecting strut width 66.
[0340] In at least one embodiment, such as for example in the
embodiment shown in FIG. 36A, the slot region width 322 may be
about 0.0025 inch while the connecting strut width is about 0.0030
inch.
[0341] As shown in the embodiments of FIGS. 35A-40 and 48-65, the
wrap portions 308a and 308b are each in communication with a common
substantially liner section 382. At the intersection of the
substantially linear section 382 and the respective wrap portions
308a and 308b is a bend portion 310a and 310b respectively present.
Depending on the type of connector 38 the bend portions 310a and
310b may define a range of angles or radii of curvature.
[0342] In some embodiments, including those depicted in FIGS. 35A,
36A, and 41-47, the connectors comprise a plurality of
interconnected substantially linear sections 382, 384 and 386
respectively. At a first bend portion 310a, the first wrap portion
308a is in communication with a first substantially linear section
382. At a second bend portion 310b, the first substantially linear
section 382 is in communication with the second substantially
linear section 384. At a third bend portion 310c the second
substantially linear section is in communication with the third
substantially linear section 386. At a fourth bend portion 310d,
the third substantially linear section 386 is in communication with
the second wrap portion 308b.
[0343] In the embodiments shown in FIGS. 35A-65, the various wrap
portions 308a and 308b, and the various substantially linear
sections 382, 384 and 386 may be substantially the same or
different from one another in their various physical
characteristics, such as length, width, thickness, cross-sectional
shape, composition, angular orientation relative to one another,
etc.
[0344] The various embodiments of the stents described herein may
include one or more coatings and/or other delivery mechanisms which
comprise one or more therapeutic agents, cellular materials,
polymeric agents, drugs, etc.
[0345] The therapeutic agent may be non-genetic or genetic.
Suitable non-genetic therapeutic agents include anti-thrombogenic
agents such as heparin, heparin derivatives, urokinase, and PPack
(dextrophenylalanine proline arginine chloromethylketone),
anti-proliferative agents such as enoxaprin, angiopeptin, or
monoclonal antibodies capable of blocking smooth muscle cell
proliferation, hirudin, and acetylsalicylic acid, anti-inflammatory
agents such as dexamethasone, prednisolone, corticosterone,
budesonide, estrogen, sulfasalazine, and mesalamine,
antineoplastic/antiproliferative/anti-miotic agents such as
paclitaxel, 5-fluorouracil, cisplatin, vinblastine, vincristine,
epothilones, endostatin, angiostatin and thymidine kinase
inhibitors, anesthetic agents such as lidocaine, bupivacaine, and
ropivacaine, anti-coagulants such as D-Phe-Pro-Arg chloromethyl
keton, an RGD peptide-containing compound, heparin, antithrombin
compounds, platelet receptor antagonists, anti-thrombin antibodies,
anti-platelet receptor antibodies, aspirin, prostaglandin
inhibitors, platelet inhibitors and tick antiplatelet peptides,
vascular cell growth promoters such as growth factor inhibitors,
growth factor receptor antagonists, transcriptional activators, and
translational promoters, vascular cell growth inhibitors such as
growth factor inhibitors, growth factor receptor antagonists,
transcriptional repressors, translational repressors, replication
inhibitors, inhibitory antibodies, antibodies directed against
growth factors, bifunctional molecules consisting of a growth
factor and a cytotoxin, bifunctional molecules consisting of an
antibody and a cytotoxin, cholesterol-lowering agents; vasodilating
agents; and agents which interfere with endogenous vascoactive
mechanisms.
[0346] Suitable genetic materials include anti-sense DNA and RNA,
DNA coding for anti-sense RNA, tRNA or rRNA to replace defective or
deficient endogenous molecules, angiogenic factors including growth
factors such as acidic and basic fibroblast growth factors,
vascular endothelial growth factor, epidermal growth factor,
transforming growth factor .alpha. and .beta., platelet-derived
endothelial growth factor, platelet-derived growth factor, tumor
necrosis factor .alpha., hepatocyte growth factor and insulin like
growth factor, cell cycle inhibitors including CD inhibitors,
thymidine kinase ("TK") and other agents useful for interfering
with cell proliferation, the family of bone morphogenic proteins
("BMP's"), BMP-2, BMP-3, BMP-4, BMP-5, BMP-6 (Vgr-1), BMP-7 (OP-1),
BMP-8, BMP-9, BMP-10, BMP-11, BMP-12, BMP-13, BMP-14, BMP-15, and
BMP-16. Any of BMP-2, BMP-3, BMP-4, BMP-5, BMP-6 and BMP-7 are
particularly desirable. These dimeric proteins can be provided as
homodimers, heterodimers, or combinations thereof, alone or
together with other molecules. Alternatively or, in addition,
molecules capable of inducing an upstream or downstream effect of a
BMP can be provided. Such molecules include any of the "hedgehog"
proteins, or the DNA's encoding them.
[0347] Suitable cellular materials include cells of human origin
(autologous or allogeneic) or from an animal source (xenogeneic),
genetically engineered if desired to deliver proteins of interest
at the transplant site. The delivery media can be formulated as
needed to maintain cell function and viability.
[0348] Suitable polymer coating materials include polycarboxylic
acids, cellulosic polymers, including cellulose acetate and
cellulose nitrate, gelatin, polyvinylpyrrolidone, cross-linked
polyvinylpyrrolidone, polyanhydrides including maleic anhydride
polymers, polyamides, polyvinyl alcohols, copolymers of vinyl
monomers such as EVA, polyvinyl ethers, polyvinyl aromatics,
polyethylene oxides, glycosaminoglycans, polysaccharides,
polyesters including polyethylene terephthalate, polyacrylamides,
polyethers, polyether sulfone, polycarbonate, polyalkylenes
including polypropylene, polyethylene and high molecular weight
polyethylene, halogenated polyalkylenes including
polytetrafluoroethylene, polyurethanes, polyorthoesters, proteins,
polypeptides, silicones, siloxane polymers, polylactic acid,
polyglycolic acid, polycaprolactone, polyhydroxybutyrate valerate
and blends and copolymers thereof, coatings from polymer
dispersions such as polyurethane dispersions (BAYHDROL.RTM., etc.),
fibrin, collagen and derivatives thereof, polysaccharides such as
celluloses, starches, dextrans, alginates and derivatives,
hyaluronic acid, squalene emulsions. Desirably, polyacrylic acid,
available as HYDROPLUS.RTM. (Boston Scientific Corporation, Natick,
Mass.), and described in U.S. Pat. No. 5,091,205, the disclosure of
which is hereby incorporated herein by reference, may be used. Also
desirably, the polymer may be a copolymer of polylactic acid and
polycaprolactone. Other materials include selected medical-grade
biodegradable materials such as PGA-TMC, Tyrosine-Derived
Polycarbonates and arylates, polycaprolactone co butyl acrylate and
other co polymers, Poly-L-lactic acid blends with DL-Lactic Acid,
Poly(lactic acid-co-glycolic acid), polycaprolactone co PLA,
polycaprolactone co butyl acrylate and other copolymers,
Tyrosine-Derived Polycarbonates and arylate, poly amino acid,
polyphosphazenes, polyiminocarbonates,
polydimethyltrimethylcarbonates, biodegradable CA/PO.sub.4's,
cyanoacrylate, 50/50 DLPLG, polydioxanone, polypropylene fumarate,
or polydepsipeptides.
[0349] Other suitable coatings include macromolecules such as
chitosan and Hydroxylpropylmethylcellulose. Surface erodible
materials may also be used. Coatings may also comprise maleic
anhydride copolymers, zinc-calcium phosphate and amorphous
polyanhydrides.
[0350] The inventive medical devices may also be provided with a
sugar or more generally a carbohydrate and/or a gelatin to maintain
the inventive medical devices on a balloon during delivery of the
medical device to a desired bodily location. Other suitable
compounds for treating the inventive medical devices include
biodegradable polymers and polymers which are dissolvable in bodily
fluids. Portions of the interior and/or exterior of the inventive
medical devices may be coated or impregnated with the compound.
Mechanical retention devices may also be used to maintain the
inventive medical devices on the balloon during delivery.
[0351] The inventive medical devices may also be provided in whole
or in part with one or more of the above therapeutic agents,
polymeric coatings or the like. Where multiple therapeutic agents
are provided, different coatings and/or mechanisms may release the
drugs at different rates. For example, one therapeutic agent may be
released at a fast rate and another therapeutic agent may be
released at a slow rate. Where multiple polymeric coatings are
provided, the coatings may degrade or erode at different rates.
[0352] In order to facilitate the retention and delivery of one or
more therapeutic agents any of the stent embodiments described
herein may be provided with a plurality of cavities or micro holes
or slits 27 other surface features, such as depicted in the
examples illustrated in FIGS. 66 and 67. The cavities 27 increase
or otherwise alter the surface area of the stent to provide the
stent 10 with a more optimum agent delivery mechanism. The cavities
27 may extend partially or entirely through the width of a given
stent component. Any of the components of the stent 10, including
the connectors 38, first and second expansion struts 28a and 28b,
first and second joining struts 30a and 30b, etc., may be provided
with one or more cavities 27.
[0353] The above disclosure is intended to be illustrative and not
exhaustive. This description will suggest many variations and
alternatives to one of ordinary skill in this art. All these
alternatives and variations are intended to be included within the
scope of the claims where the term "comprising" means "including,
but not limited to". Those familiar with the art may recognize
other equivalents to the specific embodiments described herein
which equivalents are also intended to be encompassed by the
claims.
[0354] Further, the particular features presented in the dependent
claims can be combined with each other in other manners within the
scope of the invention such that the invention should be recognized
as also specifically directed to other embodiments having any other
possible combination of the features of the dependent claims. For
instance, for purposes of claim publication, any dependent claim
which follows should be taken as alternatively written in a
multiple dependent form from all prior claims which possess all
antecedents referenced in such dependent claim if such multiple
dependent format is an accepted format within the jurisdiction
(e.g. each claim depending directly from claim 1 should be
alternatively taken as depending from all previous claims). In
jurisdictions where multiple dependent claim formats are
restricted, the following dependent claims should each be also
taken as alternatively written in each singly dependent claim
format which creates a dependency from a prior
antecedent-possessing claim other than the specific claim listed in
such dependent claim below.
[0355] This completes the description of the preferred and
alternate embodiments of the invention. Those skilled in the art
may recognize other equivalents to the specific embodiment
described herein which equivalents are intended to be encompassed
by the claims attached hereto.
* * * * *