U.S. patent application number 11/652234 was filed with the patent office on 2007-08-09 for steerable guide wire with torsionally stable tip.
Invention is credited to Steven S. Hackett, Pete T. Keith, Peter J. Ness, Thomas V. Ressemann, Steven N. Willard.
Application Number | 20070185415 11/652234 |
Document ID | / |
Family ID | 46327023 |
Filed Date | 2007-08-09 |
United States Patent
Application |
20070185415 |
Kind Code |
A1 |
Ressemann; Thomas V. ; et
al. |
August 9, 2007 |
Steerable guide wire with torsionally stable tip
Abstract
A steerable guide wire includes a core wire having a proximal
end and a distal end. A braided filament is affixed to the distal
end of the core wire. An outer coil surrounds at least a portion of
the core wire and the braided filament. A proximal end of the
braided filament is secured to a distal end of the coil. By
locating the braided filament in the distal tip portion of the
guide wire, a guide wire is provided that is highly flexible, has a
high degree of tensile integrity, and is highly steerable, even in
tortuous vasculature. Filter and balloon catheters having braided
filaments at the distal end are also described.
Inventors: |
Ressemann; Thomas V.; (St.
Cloud, MN) ; Keith; Pete T.; (St. Paul, MN) ;
Willard; Steven N.; (Bloomington, MN) ; Ness; Peter
J.; (Minneapolis, MN) ; Hackett; Steven S.;
(Maple Grove, MN) |
Correspondence
Address: |
O'MELVENY & MYERS LLP
610 NEWPORT CENTER DRIVE
17TH FLOOR
NEWPORT BEACH
CA
92660
US
|
Family ID: |
46327023 |
Appl. No.: |
11/652234 |
Filed: |
January 10, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11176485 |
Jul 7, 2005 |
|
|
|
11652234 |
Jan 10, 2007 |
|
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Current U.S.
Class: |
600/585 |
Current CPC
Class: |
A61M 25/09 20130101;
A61M 25/0133 20130101; A61M 25/09025 20130101; A61M 2025/09191
20130101; A61M 2025/09083 20130101; A61M 2025/09175 20130101 |
Class at
Publication: |
600/585 |
International
Class: |
A61M 25/00 20060101
A61M025/00 |
Claims
1. A guide wire comprising: a core wire having a proximal end and a
distal end; a braided filament disposed at the distal end of the
core wire; and a coil surrounding at least a portion of the core
wire and the braided filament.
2. The guide wire of claim 1, wherein the braided filament is
joined to the core wire by a solder joint.
3. The guide wire of claim 1, wherein the braided filament is
joined to the core wire and the coil by a solder joint.
4. The guide wire of claim 1, wherein the coil is joined to the
core wire by a solder joint.
5. The guide wire of claim 1, wherein the coil is joined to the
braided filament by a solder joint.
6. The guide wire of claim 1, wherein the core wire is tapered in a
distal region.
7. The guide wire of claim 1, wherein the coil comprises at least
one of platinum, a platinum alloy, or stainless steel.
8. The guide wire of claim 2, wherein the platinum alloy is
platinum-iridium or platinum-tungsten.
9. The guide wire of claim 1, wherein the coil comprises a proximal
coil segment and a distal coil segment.
10. The guide wire of claim 9, wherein the distal coil segment, the
proximal coil segment, the braided filament, and the core wire are
joined by a solder joint.
11. The guide wire of claim 9, wherein the distal coil segment is
coupled to the proximal coil segment.
12. The guide wire of claim 11, wherein the distal coil segment is
coupled to the proximal coil segment by threading a proximal end of
the distal coil segment into a distal end of the proximal coil
segment.
13. The guide wire of claim 1, further comprising a tip weld at a
distal end of the guide wire.
14. The guide wire of claim 13, wherein the tip weld joins a distal
end of the coil to a distal end of the braided filament.
15. The guide wire of claim 13, wherein the tip weld has a
substantially hemispherical distal portion.
16. The guide wire of claim 13, wherein the tip weld has a rounded
distal portion.
17. The guide wire of claim 13, wherein the tip weld has a pointed
tip.
18. The guide wire of claim 13, wherein the tip weld has a
wedge-shaped tip.
19. The guide wire of claim 13, wherein the tip weld has a tapered
tip.
20. The guide wire of claim 1, wherein the core wire extends
through a portion of the braided filament.
21. The guide wire of claim 1, wherein the core wire extends
through the braided filament to a distal end of the braided
filament.
22. The guide wire of claim 1, wherein the core wire extends
through the braided filament to a tip weld at the distal end of the
guide wire.
23. The guide wire of claim 1, wherein the braided filament is
unitary with the core wire.
24. A method for placing a guide wire in a vessel; comprising the
steps of: providing a guide wire comprising a core wire having a
proximal end and a distal end, a braided filament disposed at the
distal end of the core wire; and a coil surrounding at least a
portion of the core wire and the braided filament; and advancing
the guide wire into the vessel.
25-28. (canceled)
29. A guide wire comprising: a core wire having a proximal end and
a distal region, the distal region having a segment that comprises
a slotted segment with repeating alternating first and second
regions, wherein the first region has a first cross-sectional width
and wherein the second region has a second cross-sectional width,
wherein the first cross-sectional width is smaller than the second
cross-sectional width; and a coil surrounding at least a portion of
the core wire.
30-45. (canceled)
46. A method for placing a guide wire in a vessel; comprising the
steps of: providing a core wire having a proximal end and a distal
region, the distal region having a segment that comprises a slotted
segment with repeating alternating first and second regions,
wherein the first region has a first cross-sectional width and
wherein the second region has a second cross-sectional width,
wherein the first cross-sectional width is smaller than the second
cross-sectional width, and a coil surrounding at least a portion of
the core wire; and advancing the guide wire into the vessel.
47-50. (canceled)
51. A guide wire comprising: a core wire having a proximal end and
a distal end; an elongate tubular member having a proximal end, a
distal end, and a lumen therebetween, wherein at least a portion of
the core wire is disposed within the lumen of the elongate tubular
member; and a coil surrounding at least a portion of the core wire
and the elongate tubular member.
52-70. (canceled)
71. A method for placing a guide wire in a vessel; comprising the
steps of: providing a core wire having a proximal end and a distal
end, an elongate tubular member having a proximal end, a distal
end, and a lumen therebetween, wherein at least a portion of the
core wire is disposed within the lumen of the elongate tubular
member, and a coil surrounding at least a portion of the core wire
and the elongate tubular member.; and advancing the guide wire into
the vessel.
72-75. (canceled)
76. A medical device comprising: an elongate tubular member having
a proximal end, a distal region, a balloon disposed on the distal
region, and an inflation lumen communicating with the balloon and
extending proximally from the balloon; a braided filament extending
distally from the distal region of the elongate tubular member; and
a coil surrounding at least a portion of the braided filament.
77-88. (canceled)
89. A method for treating a lesion in a vessel, comprising the
steps of: providing a medical device comprising: an elongate
tubular member having a proximal end, a distal region, a dilatation
balloon disposed on the distal region, and an inflation lumen
communicating with the dilatation balloon and extending proximally
from the dilatation balloon; a braided filament extending distally
from the distal region of the elongate tubular member; and a coil
surrounding at least a portion of the braided filament; advancing
the medical device into the vessel; locating the dilatation balloon
within the lesion; and expanding the dilatation balloon to dilate
the lesion.
90. (canceled)
91. A method for treating a lesion in a vessel, comprising the
steps of: providing a medical device comprising: an elongate
tubular member having a proximal end, a distal region, an occlusion
balloon disposed on the distal region, and an inflation lumen
communicating with the occlusion balloon and extending proximally
from the occlusion balloon; a braided filament extending distally
from the distal region of the elongate tubular member; and a coil
surrounding at least a portion of the braided filament; advancing
the medical device into the vessel; locating the occlusion balloon
distal the lesion; and expanding the occlusion balloon to occlude
the vessel.
92-93. (canceled)
94. A medical device comprising: an elongate tubular member having
a proximal end, a distal region, an expandable filter disposed on
the distal region, and an actuation mechanism operable to expand
the expandable filter; a braided filament extending distally from
the distal region of the elongate tubular member; and a coil
surrounding at least a portion of the braided filament.
95-104. (canceled)
105. A method for treating a vessel having a lesion, comprising the
steps of: providing a medical device comprising: an elongate
tubular member having a proximal end, a distal region, an
expandable filter disposed on the distal region, and an actuation
mechanism operable to expand the expandable filter; a braided
filament extending distally from the distal region of the elongate
tubular member; and a coil surrounding at least a portion of the
braided filament; advancing the medical device into the vessel;
locating the expandable filter distal the lesion; and operating the
actuation mechanism to expand the expandable filter.
106-107. (canceled)
Description
RELATED APPLICATIONS
[0001] This is a continuation-in-part of U.S. application Ser. No.
11/176,485, filed Jul. 7, 2005, which is hereby incorporated by
reference in its entirety.
FIELD OF THE INVENTION
[0002] The field of the invention generally relates to guide wires.
More particularly, the field of the invention relates to steerable
guide wires used to access a site of interest inside a body lumen
from a remote position located outside the body.
BACKGROUND OF THE INVENTION
[0003] Catheter based vascular interventions are becoming
increasingly common in many of the vascular beds of the human body.
For example, the treatment of obstructive plaque (e.g., stenosis)
in coronary, peripheral, and cerebral arteries via angioplasty
(with or without stents) has become a routine procedure. There
remains a need, however, to improve the devices used in these
procedures, to make them faster, easier, safer, and more viable,
particularly in challenging anatomical situations.
[0004] The vast majority of catheter-based vascular interventions
make use of a steerable guide wire to access the site of interest
from a remote position outside the body. For example, in coronary
interventions such as stent implantation, a steerable guide wire is
advanced from the femoral artery access site into the various
branches of coronary arteries and across the obstructive plaque.
FIG. 5 illustrates the tip of a coronary guide wire accessing a
coronary vessel with an obstructive plaque. After the guide wire is
advanced past the stenosis, an interventional device such as a
stent delivery balloon catheter (not shown) is advanced over the
guide wire and through the stenosis. Thus, it is the guide wire
that establishes the pathway for the interventional catheter that
follows.
[0005] Steerability is an important performance characteristic for
a steerable guide wire. Steerability generally refers to the
ability to controllably rotate the distal tip of the guide wire to
"point" the tip in the desired direction during the advancement
procedure. Steerable guide wires typically have a "J" bend (for
example, as seen in FIG. 5) imparted to the tip, either by the
operator prior to the introduction into the body, or by the
manufacturer. The ability to controllably orient this "J" bend
allows the guide wire to be navigated into different branches of
vessels and across the stenosis.
[0006] The ideal or optimum controllability of the tip of the guide
wire is referred to as "1:1 torque response." This term refers to
the ability of the tip to rotate exactly in step with rotation of
the proximal end of the guide wire. For example, if the proximal
end of the guide wire is rotated through 90 degrees, the tip will
ideally rotate through 90 degrees--hence a 1:1 response. [0007]
Several factors influence the steerability qualities of a steerable
guide wire. These include torsional stiffness of the guide wire
components, dimensions, torsional modulus, guide wire straightness,
guide wire resilience (ability to bend without plastically
deforming), lubricity, and cross-sectional configuration.
Steerability is also impacted by the tortuosity of the vascular
anatomy.
[0007] Another important characteristic of a steerable guide wire
is its tensile strength/integrity. This term generally refers to
the guide wire's ability to withstand tensile forces applied to it
without breaking. For example, the tips of guide wires occasionally
get lodged in the stenosis or elsewhere in the vasculature, and
when this happens, it is important to be able to dislodge the tip
by pulling on the proximal end of the guide wire. The design of
prior art steerable guide wires has thus involved a balance or
trade-off between optimizing flexibility and steerability while at
the same time maintaining tensile integrity.
[0008] FIGS. 1A-1D illustrates a typical construction of a prior
art steerable guide wire, such as those commonly used in coronary
interventions. As seen in FIG. 1A, the guide wire generally
includes three portions, a proximal portion, a mid-portion, and a
distal tip portion. There are two main components in steerable
guide wires, a core wire that extends from a proximal end to a
distal end, and a coil that extends over the mid-portion and tip
portion of the guide wire. Lubricious coatings such as PTFE and/or
hydrophilic or hydrophobic materials may also be present over some
or all portions of the guide wire.
[0009] The core wire component of the guide wire is typically
fabricated of high tensile strength stainless steel wire; however
other materials are also used, such as NITINOL, MP35N, or ELGILOY.
The guide wire is relatively stiff in the proximal portion and
becomes increasingly more flexible towards the distal end. The
proximal portion is typically of the original wire diameter (e.g.,
0.014 inches for a coronary guide wire). The mid-portion is made
more flexible by grinding down the diameter of the core wire to one
or more smaller dimensions (e.g., 0.005 to 0.010 inches).
[0010] The distal tip portion of the guide wire is made even more
flexible by further grinding of the core wire to a smaller
dimension (e.g., 0.002 to 0.003 inches). While grinding the core
wire to these smaller diameters does impart flexibility to the core
wire, it is typically still not flexible enough for the tip portion
to be atraumatic to the vasculature. Therefore the dimension of the
core wire in the tip region is reduced even further by stamping or
rolling the round wire into a flat ribbon configuration. The ribbon
structure is illustrated in FIGS. 2A and 2B, as well as Section C-C
in FIG. 1D. As seen in FIGS. 1D, 2A, and 2B, the ribbon is formed
integrally with the core wire. In an alternative method of
manufacture, however, it is also known to attach a separately
formed piece of ribbon to a distal end of the mid portion of the
core wire.
[0011] The high degree of flexibility achieved by the ribbon
configuration could theoretically be accomplished by grinding the
core wire to a round dimension that gives the equivalent stiffness
of the ribbon. Unfortunately, however, the cross-sectional area of
such a round wire would be substantially less than the
cross-sectional area of the ribbon configuration. Therefore, the
tensile integrity of the core wire would be significantly lowered.
In a commonly used steerable coronary guide wire, the dimensions of
the ribbon structure of the tip portion are approximately 0.001 by
0.003 inches. Such dimensions in a high tensile strength stainless
steel core wire yield a tip portion with a high degree of
flexibility and a tensile strength of approximately 0.9 lbs, which
is close to the minimum acceptable tensile strength integrity for
the tip portion of the guide wire.
[0012] While the prior art guide wire described above has a tip
portion with good flexibility and acceptable tensile integrity, it
does have compromised steerability as a result of the ribbon
structure in the tip portion. The ribbon portion is typically about
2 cm in length. Any time the tip portion is positioned in a
tortuous region of the vasculature (such as illustrated in FIG. 5),
the ribbon will naturally bend only in the direction perpendicular
to the ribbon's widest dimension (e.g., out of the plane of the
page as shown in FIG. 2B). For a ribbon structure, there are thus
only two stable bending directions 180 degrees apart from each
other.
[0013] If, in this anatomical setting, the guide wire is rotated in
an effort to steer the tip, the tip will resist rotating. Torque or
energy will be stored in the ribbon in the form of a twist in the
proximal region of the ribbon, as well as in the core wire
extending proximally from the ribbon. Continued rotation of the
proximal end of the guide wire will cause enough torque to build up
such that the tip portion will suddenly rotate or "whip" to its
next stable orientation. This orientation is 180 degrees from the
previous orientation. Therefore, the ability to rotate the tip to
orientations between 0 and 180 degrees is hampered. Similarly, if
the guide wire is further rotated, the tip portion will again
resist rotating until enough torque is built up and then the tip
will suddenly rotate an additional 180 degrees.
[0014] There is thus a need for a steerable guide wire that
exhibits controllable steering of the tip even in anatomically
challenging vasculature. Such a steerable guide wire should have
excellent steerability, tip flexibility, as well as tensile
integrity. Moreover, there is a further need for a guide wire that
is able to be rotated at the proximal end without any "whipping" of
the distal tip.
SUMMARY OF THE INVENTION
[0015] The present invention provides for a steerable guide wire
that dramatically improves steerability without compromising
tensile integrity or flexibility.
[0016] In one aspect of the invention, a steerable guide wire
includes a core wire having a proximal end and a distal end. A
multi-filament bundle is affixed to the distal end of the core
wire. An outer coil surrounds at least a portion of the core wire
and the multi-filament bundle. A proximal end of the multi-filament
bundle is secured to a distal end of the coil. By locating the
multi-filament bundle in the distal tip portion of the guide wire,
a guide wire is provided that is highly flexible, has a high degree
of tensile integrity, and is highly steerable, even in tortuous
vasculature.
[0017] In another aspect of the invention, a guide wire includes a
proximal portion including a core wire and a distal portion that
includes a multi-filament bundle coupled to the distal end of the
core wire.
[0018] In yet another aspect of the invention, a guide wire
includes a core wire having a proximal end and a distal end and a
multi-filament bundle disposed at the distal end of the core wire,
the multi-filament bundle including a plurality of filaments that
are twisted in a common direction. A coil surrounds at least a
portion of the core wire and the multi-filament bundle.
[0019] In one aspect of the invention, the multi-filament bundle
includes a central filament and a plurality of outer filaments. In
an alternative aspect of the invention, the multi-filament bundle
includes a central filament surrounded by a plurality of filament
bundles. Each bundle includes a plurality of individual
filaments.
[0020] In one aspect of the invention, the multi-filament bundle
may be made of a central filament formed from a first material and
a plurality of outer filaments formed from a second material. For
example, the central filament may be formed from a radiopaque
material.
[0021] In another aspect of this invention, a guide wire includes a
core wire having a proximal end and a distal end. The guide wire
also includes a braided filament disposed at the distal end of the
core wire. A coil surrounds at least a portion of the core wire and
the braided filament. In one embodiment, the core wire may extend
through the braided filament to the distal end of the braided
filament. In another embodiment, the core wire extends through only
a portion of the braided filament. In yet another embodiment, the
braided filament is unitary with the core wire.
[0022] In another aspect of this invention, a guide wire includes a
core wire having a proximal end and a distal region, the distal
region having a segment that comprises a slotted segment with
repeating alternating first and second regions. In the slotted
segment, the first region has a first cross-sectional width that is
smaller than a second cross-sectional width of the second region. A
coil surrounds at least a portion of the core wire.
[0023] In another aspect of this invention, a guide wire includes a
core wire having a proximal end and a distal end. The guide wire
also includes an elongate tubular member having a proximal end, a
distal end, and a lumen therebetween, wherein at least a portion of
the core wire is disposed within the lumen of the elongate tubular
member. A coil surrounds at least a portion of the core wire and
the elongate tubular member.
[0024] In another aspect of this invention, methods of use are
provided for the above-described guide wires wherein the guide
wires are advanced into a vessel of interest.
[0025] In another aspect of this invention, a balloon catheter
includes an elongate tubular member having a proximal end, a distal
region, a balloon disposed on the distal region, and an inflation
lumen communicating with the balloon and extending proximally from
the balloon. The balloon catheter also includes a braided filament
extending distally from the distal region of the elongate tubular
member and a coil surrounding at least a portion of the braided
filament. The balloon may be a dilatation balloon or an occlusion
balloon.
[0026] In another aspect of this invention, a method for using a
dilatation balloon catheter to treat a vessel having a lesion is
described. A balloon catheter as described above is provided,
wherein the balloon catheter has a dilatation balloon disposed on
the distal region. The balloon catheter is then advanced into the
vessel and positioned such that the dilatation balloon is located
at the lesion. The dilatation balloon is then expanded to dilate
the lesion. Optionally, a catheter having a stent may then be
advanced over the elongate tubular member and the stent may be
expanded at the site of the lesion.
[0027] In another aspect of this invention, a method for using an
occlusion balloon catheter to treat a vessel having a lesion is
described. A balloon catheter as described above is provided,
wherein the balloon catheter has an occlusion balloon disposed on
the distal region. The balloon catheter is then advanced into the
vessel and positioned such that the occlusion balloon is located
distal the lesion. The occlusion balloon is then expanded to
occlude the vessel. A catheter having a dilatation balloon may then
be advanced over the elongate tubular member and the dilatation
balloon may then be expanded to dilate the lesion. Additionally or
alternatively, a catheter having a stent may be advanced over the
elongate tubular member and the stent may be expanded at the site
of the lesion.
[0028] It is an object of the invention to provide a guide wires
and catheters that are highly flexible, have a high degree of
tensile integrity, and are highly steerable, even in tortuous
vasculature. Additional objects of invention are discussed below
with reference to the drawings and the description of the preferred
embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIG. 1A is a side view of a guide wire according to the
prior art. FIG. 1A further includes partial cross-sectional views
illustrating the core wire portion under the outer coil.
[0030] FIG. 1B is a cross-sectional view of the proximal shaft
portion of the guide wire taken along the line A-A of FIG. 1A.
[0031] FIG. 1C is a cross-sectional view of the mid-shaft portion
of the guide wire taken along the line B-B of FIG. 1A.
[0032] FIG. 1D is a cross-sectional view of the distal tip portion
of the guide wire taken along the line C-C of FIG. 1A.
[0033] FIG. 2A is a magnified side view of the dashed region of
FIG. 1A.
[0034] FIG. 2B is a magnified top view of the dashed region of FIG.
1A. The top view is generally perpendicular to the view shown in
FIG. 2A. FIG. 2B illustrates the width of the ribbon structure
according to the prior art.
[0035] FIG. 3 illustrates side a view of a guide wire according to
one-aspect of the invention.
[0036] FIG. 4A illustrates a magnified view of a cross-section of
the distal tip portion of a guide wire according to one aspect of
the invention.
[0037] FIG. 4B illustrates a cross-sectional view of the distal tip
portion of the guide wire taken along the line D-D in FIG. 4A
according to one embodiment of the invention.
[0038] FIG. 4C illustrates a cross-sectional view of the distal tip
portion of the guide wire taken along the line D-D in FIG. 4A
according to another embodiment of the invention.
[0039] FIG. 4D illustrates a cross-sectional view of the distal tip
portion of the guide wire taken along the line D-D in FIG. 4A
according to another embodiment of the invention.
[0040] FIG. 4E illustrates a cross-sectional view of the distal tip
portion of the guide wire taken along the line D-D in FIG. 4A
according to another embodiment of the invention.
[0041] FIG. 5 illustrates a guide wire according to the present
invention being advanced in a side branch of a vessel.
[0042] FIG. 6 illustrates a magnified view of a cross-section of
the distal tip portion of a guide wire according to another aspect
of the invention.
[0043] FIG. 7 illustrates a magnified view of a cross-section of
the distal tip portion of a guide wire having a braided filament
according to one aspect of the invention.
[0044] FIG. 8 illustrates a magnified view of a cross-section of
the distal tip portion of a guide wire having a braided filament
according to another aspect of the invention.
[0045] FIG. 9 illustrates a magnified view of a cross-section of
the distal tip portion of a guide wire having a braided region
according to another aspect of the invention.
[0046] FIG. 10A illustrates a magnified view of a cross-section of
the distal tip portion of a guide wire having a slotted region
according to another aspect of the invention.
[0047] FIG. 10B illustrates an alternative view of the guide wire
of FIG. 10A having a slotted region.
[0048] FIG. 11 illustrates a magnified view of a cross-section of
the distal tip portion of a guide wire having an elongate tubular
member extending from a core wire according to another aspect of
the invention.
[0049] FIG. 12A illustrates a magnified view of a distal end of a
guide wire having a tip weld with a tapering, rounded tip.
[0050] FIG. 12B illustrates a magnified view of a distal end-of a
guide wire having a tip weld with a pointed or wedge-shaped
tip.
[0051] FIG. 13 illustrates a balloon catheter with a distal tip
having a braided portion.
[0052] FIG. 14 illustrates a filter wire having a distal tip having
a braided portion.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0053] FIG. 3 illustrates a guide wire 2 according to one preferred
aspect of the invention. The guide wire 2 generally includes a
proximal portion A, a mid portion B, and a distal tip portion C.
The guide wire 2 includes a solid core wire 4 that traverses the
proximal and mid portions A, B and terminates in or near the distal
tip portion C. As seen in FIG. 3, the diameter of the core wire 4
is reduced in the mid portion B of guide wire 2 to increase its
flexibility. The distal end 4a of the core wire 4 is coupled to a
multi-filament bundle 6. The multi-filament bundle 6 projects
distally from the distal end 4a of the core wire 4 and terminates
in a distal tip portion 8. The guide wire 2 further includes a coil
10 that is wrapped or wound around a portion of the exterior of the
core wire 4 and multi-filament bundle 6. As seen in FIG. 3, the
coil 10 begins in the mid portion B of the guide wire 2 and
terminates at the distal tip 8. The distal tip 8 may include an end
cap 12 such as a weld, braze, solder, adhesive, or the like to
secure the distal most end of the multi-filament bundle 6.
[0054] The proximal and mid portions A, B of the guide wire 2 may
be formed of any material suitable for guide wires including, but
not limited to, 304 stainless steel, 316 stainless steel, NITINOL,
MP35N, or ELGILOY. Fabrication of the proximal and mid portions A,
B of the guide wire 2 may make use of methods and techniques such
as center less grinding and/or chemical etching. The outer coil 10
may be formed of stainless steel or other suitable materials. In
one aspect of the invention, the entire outer coil 10 or one or
more sections thereof can incorporate radiopaque materials such as
platinum/iridium, gold, or the like. Alternatively, in place of the
outer coil 10, a polymer jacket, preferably loaded with radiopaque
material such as barium sulfate or bismuth subcarbonate may be
secured over all or portions of the core wire 4 and multi-filament
bundle 6. Moreover, the guide wire 2 may include one or more
lubricious coatings (not shown) that are applied to the guide wire
2 or portions thereof.
[0055] Still referring to FIG. 3, the core wire 4 terminates at or
near the distal end of the mid portion B of the guide wire 2. In
one preferred aspect of the invention, a multi-filament bundle 6 is
attached or otherwise mechanically connected to the distal end of
the core wire 4. The multi-filament bundle 6 extends to the distal
tip portion 8 of the guide wire 2.
[0056] The multi-filament bundle 6 includes a plurality of
individual filaments 6a that are arranged in a bundle, for example,
as shown in FIG. 4A. In one aspect of the invention, the
multi-filament bundle 6 may be formed of two or more individual
wire filaments of high tensile strength material such as 304
stainless steel or 316 stainless steel or other suitable materials.
In a preferred embodiment, the multi-filament bundle 6 may include
stranded wire cable formed of seven wire-filaments 6a, as depicted
in FIG. 4B.
[0057] Alternatively, the multi-filament bundle 6 may be formed
from three filaments 6a (e.g., wire filaments) as is depicted in
FIG. 4C. A stranded wire cable comprising three or seven wire
filaments 6a of the same diameter may be preferred as it is
generally more structurally stable than stranded wire bundles of
other numbers of wire filaments. However, the present guide wire 2
contemplates using a multi-filament bundle 6 of any number of
filaments 6a greater than two. In addition, the multi-filament
bundle 6 may be formed from a multi-filament inner core surrounded
by a plurality of outer filaments.
[0058] In one aspect of the invention, the multi-filament bundle 6
includes a seven filament 6a stranded wire cable of high tensile
strength stainless steel. The length of the multi-filament bundle 6
is preferably between 1 and 4 cm and most preferably about 2 cm,
although other lengths are also contemplated by the scope of the
present invention. The filaments 6a are preferably about 0.0005
inch to 0.0015 inch diameter and most preferably about 0.0008 to
0.0010 inch diameter. For example, FIGS. 4A and 4B illustrate
multi-filament bundle 6 in the form of a stranded wire bundle that
is arranged with a central filament 6a surrounded by six outer
filaments 6a all twisted in a common direction.
[0059] In an alternative embodiment, the multi-filament bundle 6 is
formed from three filaments 6a as is depicted in FIG. 4C. In this
embodiment, to achieve a tip portion of comparable flexibility to a
guide wire 2 of the above embodiment (FIGS. 4A and 4B), the wire
filaments 6a are preferably somewhat larger in diameter.
[0060] FIG. 4D illustrates a further embodiment wherein the central
filament 6a is of a different dimension (i.e., diameter) than the
outer filaments 6a'. For example, there may be a single central
filament 6a and at least 7 outer filaments 6a'. FIG. 4E depicts a
further alternative embodiment wherein the multi-filament bundle 6
includes one or more filament bundles 6b. As seen in FIG. 4E, a
central filament 6a is surrounded by six filament bundles 6b. Each
filament bundle 6b is formed from a plurality of filaments 6a.
[0061] Each of the multi-filament bundle 6 arrangements depicted
above can be tailored to have particular characteristics regarding
flexibility, tensile strength, torsional stiffness, and tip
formability (e.g., the ability to form a "J" bend such as that
shown in FIG. 5). For instance, the arrangements depicted may
incorporate one or more filaments 6a that are formed from different
materials or have different properties than the other filament(s).
By way of illustration and not limitation, in the arrangements
depicted in FIGS. 4B and 4D, the central filament 6a may be
fabricated of a radiopaque material such as platinum, while the
outer filaments may be constructed of high tensile strength
stainless steel. In yet another illustrative example, the central
filament 6a could be fabricated of a more ductile material such as
annealed or low tensile strength stainless steel and the outer
filaments 6a' of high tensile strength stainless steel. This
particular configuration would allow for the tip portion C to be
highly formable yet retain high tensile strength due to the high
tensile strength of the outer filaments 6a'.
[0062] In a further embodiment, the configuration depicted in FIGS.
4D and 4E may utilize high strength polymeric materials for one or
more of the filaments 6a or filament bundles 6b. For example, in
FIG. 4E, the central filament 6a could be formed of stainless steel
and the outer filament bundles could be formed of a high strength
polymer such as polyester, nylon, PTFE, or UHMWPE (Ultra High
Molecular Weight Poly Ethylene) such as SPECTRA. The polymer
bundles 6b could be twisted around the central filament 6a or,
alternatively, they could be arranged in a braided configuration
around central filament 6a.
[0063] It is further contemplated that the arrangements depicted in
FIGS. 4B and 4D could have the outer filaments 6a' arranged as a
braid (not shown). Alternatively, one or more of the outer
filaments 6a' could be wound in a direction opposite that of the
other outer filaments 6a' (e.g., counter-wound filaments). It is
also contemplated that in the arrangements of FIGS. 4B and 4D that
if the outer filaments 6a are in a braided configuration, there may
be no central filament 6a as is shown in FIG. 6.
[0064] The attachment of multi-filament bundle 6 to the distal end
4a of the core wire 4 can be accomplished by any suitable means
such as soldering, brazing, welding, crimping band, shape recovery
band, or adhesive bonding. The distal end of the multi-filament
bundle 6 can be attached to the distal end of the outer coil 10 by
suitable means including soldering, brazing, welding, or adhesive
bonding.
[0065] FIG. 7 illustrates a guide wire 20 according to another
preferred aspect of the invention. The guide wire 20 generally
includes a proximal portion A (not shown), a mid portion B, and a
distal tip portion C. The guide wire 20 includes a solid core wire
24 that traverses the proximal and mid portions A, B and terminates
in or near the distal tip portion C. As seen in FIG. 7, the
diameter of the core wire 24 is reduced in the mid portion B of
guide wire 20 to increase its flexibility. The distal end 24a of
the core wire 24 is coupled to a braided filament 26. The braided
filament 26 projects distally from the distal end 24a of the core
wire 24 and terminates in a distal tip 28. The distal end 24a of
the core wire 24 may extend into approximately 1/4 of the total
length of the braided filament, alternatively into approximately
1/3 of the total length of the braided filament, alternatively into
approximately 1/2 of the total length of the braided filament,
approximately 3/4 of the total length of the braided filament. The
braided filament 26 may be about 2 cm in length, alternatively
about 3 cm in length, alternatively about 4 cm in length,
alternatively about 5 cm in length, alternatively about 6 cm in
length, alternatively about 7 cm in length, alternatively about 8
cm in length. The guide wire 20 further includes first and second
coils 30, 32 that surround a portion of the exterior of the core
wire 24 and braided filament 26. As seen in FIG. 7, the first coil
30 begins in the proximal end of portion B of the guide wire 20 and
terminates at around the proximal end of distal tip portion C.
Second coil 32 begins at or around the proximal end of distal tip
portion C and terminates at the distal tip 28. The material of the
first coil is preferably stainless steel, and the material of the
second coil is preferably a platinum alloy to provide radiopacity.
The distal tip 28 may include an end cap 34 such as a weld, braze,
solder, adhesive, or the like to secure the distal most end of the
braided filament 26.
[0066] FIG. 8 illustrates a guide wire 40 according to another
preferred aspect of the invention. The guide wire 40 generally
includes a proximal portion A (not shown), a mid portion B, and a
distal tip portion C. The guide wire 40 includes a solid core wire
44 that traverses the proximal and mid portions A, B and terminates
at the distal end of the guide wire 40. As seen in FIG. 8, the
diameter of the core wire 44 is reduced in the mid portion B of
guide wire 40 to increase its flexibility. The core wire 44 in the
distal tip portion is surrounded by a braided filament 26. Both the
braided filament 26 and the core wire 44 terminate at the distal
tip 28. The braided filament 26 may be about 2 cm in length,
alternatively about 3 cm in length, alternatively about 4 cm in
length, alternatively about 5 cm in length, alternatively about 6
cm in length, alternatively about 7 cm in length, alternatively
about 8 cm in length. The guide wire 20 further includes first and
second coils 30, 32 that are wrapped or wound around a portion of
the exterior of the core wire 24 and braided filament 26. As seen
in FIG. 8, the first coil 30 begins in the proximal end of portion
B of the guide wire 20 and terminates at around the proximal end of
distal tip portion C. Second coil 32 begins at or around the
proximal end of distal tip portion C and terminates at the distal
tip 28. The distal tip 28 may include an end cap 34 such as a weld,
braze, solder, adhesive, or the like to secure the distal most ends
of the braided filament 26 and the core wire 44.
[0067] FIG. 9 illustrates a guide wire 50 according to another
preferred aspect of the invention. The guide wire 50 generally
includes a proximal portion A (not shown), a mid portion B, and a
distal tip portion C. The guide wire 50 includes a core wire 54
that traverses the proximal, mid portions, and distal tip portions
A, B, and C and terminates at the distal end of the guide wire 50.
As seen in FIG. 9, the diameter of the core wire 54 is reduced in
the mid portion B of guide wire 40 to increase its flexibility.
Core wire 54 has a unibody construction. In the distal tip portion
C, a distal region of the core wire 54a has been cut into multiple
strands (2, 3, 4, 5, or 6 strands) and the multiple strands have
been braided or otherwise twisted together. Where there are four
strands braided together, the distal region of the core wire 54a
could be made by cutting a portion of the core wire in half to form
two strands, turning the guide wire 90 degrees, and cutting the
core wire in half again to form four total strands. The four
strands could then be braided together or otherwise twisted
together to form the distal end braided portion of the core wire.
The braided region 54a of the core wire may be about 2 cm in
length, alternatively about 3 cm in length, alternatively about 4
cm in length, alternatively about 5 cm in length, alternatively
about 6 cm in length, alternatively about 7 cm in length,
alternatively about 8 cm in length. The braided core wire 54
terminates at the distal tip 28. The guide wire 50 further includes
first and second coils 30, 32 that are wrapped or wound around a
portion of the exterior of the core wire 54. As seen in FIG. 9, the
first coil 30 begins in the proximal end of portion B of the guide
wire 50 and terminates at around the proximal end of distal tip
portion C. Second coil 32 begins at or around the proximal end of
distal tip portion C and terminates at the distal tip 28. The
distal tip 28 may include an end cap 34 such as a weld, braze,
solder, adhesive, or the like to secure the distal most end of the
braided core wire 54.
[0068] FIGS. 10A and B illustrate a guide wire 60 according to
another preferred aspect of the invention. The guide wire 60
generally includes a proximal portion A (not shown), a mid portion
B, and a distal tip portion C. The guide wire 60 includes a core
wire 64 that traverses the proximal and mid portions A, B and
terminates at the distal end of the guide wire 60. The core wire
has a unibody construction and has a solid proximal portion and a
slotted distal portion 64a. As seen in FIG. 10A, the diameter of
the core wire 64 is reduced in the mid portion B of guide wire 40
to increase its flexibility. In the distal tip portion C, multiple
slots have been cut into a distal region of the core wire 64a. The
slotted segment 64a includes repeating alternating first and second
regions, wherein the first region has a first cross-sectional width
and the second region has a second cross-sectional width. In this
slotted region, the first cross-sectional width is repeated at
least 3 times, alternatively at least 5 times, alternatively at
least 7 times. The slotted core wire 64 terminates at the distal
tip 28. The slotted region 64a of the core wire may be about 2 cm
in length, alternatively about 3 cm in length, alternatively about
4 cm in length, alternatively about 5 cm in length, alternatively
about 6 cm in length, alternatively about 7 cm in length,
alternatively about 8 cm in length. The slotted segment could be
made by laser cutting, electro-chemical etching, stamping, or
electrical discharge machining. The guide wire 60 further includes
first and second coils 30, 32 that are wrapped or wound around a
portion of the exterior of the core wire 54. As seen in FIG. 10A,
the first coil 30 begins in the proximal end of portion B of the
guide wire 60 and terminates at around the proximal end of distal
tip portion C. Second coil 32 begins at or around the proximal end
of distal tip portion C and terminates at the distal tip 28. The
distal tip 28 may include an end cap 34 such as a weld, braze,
solder, adhesive, or the like to secure the distal most end of the
slotted core wire 44a.
[0069] FIG. 11 illustrates a guide wire 70 according to another
preferred aspect of the invention. The guide wire 70 generally
includes a proximal portion A (not shown), a mid portion B, and a
distal tip portion C. The guide wire 70 includes a solid core wire
74 that traverses the proximal and mid portions A, B and terminates
in or near the distal tip portion C. As seen in FIG. 11, the
diameter of the core wire 74 is reduced in the mid portion B of
guide wire 20 and tapers to a pointed or wedge-shaped distal tip to
increase its flexibility. The distal end 74a of the core wire 74 is
coupled to the elongate tubular member 76. In one embodiment, the
distal end 74a of the core wire 74 may be disposed within a lumen
of the elongate tubular member 76. A solder joint may also couple
the distal end 74a of the core wire 74 to the elongate tubular
member 76. The elongate tubular member 76 projects distally from
the distal end 74a of the core wire 74 and terminates in a distal
tip 28. The elongate tubular member 76 could me made of a
biocompatible metal such as nitinol or a polymer. The elongate
tubular member 76 may also include slots to increase the
flexibility of the tubular member. The slots may be made using
laser cutting, die cutting, etching, or electrical discharge
machining. The goal of the design is to enable the doctor to be
able to torque the guide wire without whipping the tip when
navigating tortuous anatomy. A 1:1 steering response to torque
response is desired. The guide wire 70 further includes first and
second coils 30, 32 that are wrapped or wound around a portion of
the exterior of the core wire 74 and elongate tubular member 76. As
seen in FIG. 11, the first coil 30 begins in the and second coils
30, 32 that are wrapped or wound around a portion of the exterior
of the core wire 74 and elongate tubular member 76. As seen in FIG.
11, the first coil 30 begins in the proximal end of portion B of
the guide wire 70 and terminates at around the proximal end of
distal tip portion C. Second coil 32 begins at or around the
proximal end of distal tip portion C and terminates at the distal
tip 28. The distal tip 28 may include an end cap 34 such as a weld,
braze, solder, adhesive, or the like to secure the distal most end
of the elongate tubular member 76.
[0070] With reference to the above embodiments, the proximal and
mid portions A, B of the guide wire may be formed of any material
suitable for guide wires including, but not limited to, 304
stainless steel, 316 stainless steel, NITINOL, MP35N, or ELGILOY.
Fabrication of the proximal and mid portions A, B of the guide wire
may make use of methods and techniques such as center less grinding
and/or chemical etching.
[0071] In the above embodiments, the first and second coils 30, 32
are wrapped around a portion of the mid-portion and distal tip
portion of the guide wire. The first coil 30, which is wrapped
around at least a portion of mid-portion B of the guide wire, may
be made out of a biocompatible material such as stainless steel.
The first coil may be approximately 11-22 cm long, alternatively
approximately 12-20 cm long, alternatively approximately 14-20 cm
long. The second coil 32, which is wrapped around at least a
portion of distal tip portion C of the guide wire, may be made out
of a biocompatible material such as platinum or a
platinum-containing alloy such as Platinum-Iridium or
Platinum-Tungsten, or a combination thereof. The second coil 32 may
be approximately 2 cm long, alternatively approximately 3 cm long,
alternatively approximately 4 cm long, alternatively approximately
5 cm long, alternatively approximately 6 cm long. The proximal end
of the first coil may be attached to the core wire through a solder
joint 35. The distal end of the first coil and the proximal end of
the second coil may be connected or otherwise coupled together. In
one embodiment, the first and second coils may be joined in a
threaded region 36, i.e., at least one turn of the distal end of
the first coil may be threaded into at least one turn of the
proximal end of the second coil. Additionally, the threaded region
36 may be coupled to the core wire through a solder joint 37.
Alternatively, in another embodiment, the coils may not be threaded
together but may be joined to each other and/or the core wire with
one or more solder joints.
[0072] In the above embodiment, the distal end of guide wire ends
in a tip weld 34. Depending on the embodiment, as seen in FIG. 7,
the tip weld 34 may join the braided filament 26 and the second
coil 32. Alternatively, as seen in FIG. 8, the tip weld may join
the core wire, the braided filament 26, and the second coil 32.
Alternatively, as seen in FIG. 9, the tip weld may join the braided
portion 54a of the core wire and the second coil 32. Alternatively,
as seen in FIG. 10A, the tip weld may join the slotted portion 64a
of the core wire and the second coil 32. Alternatively, as seen in
FIG. 11, the tip weld may join the elongate tubular member 76 and
the second coil 32. The tip weld may have a rounded portion and/or
have a distal portion that is substantially hemispherical in shape
(see FIGS. 7-10A). Alternatively, the tip weld may have a tapered
shape, as seen in FIG. 12A. The tip weld may also have a wedge
shape, as seen in FIG. 12B.
[0073] The configurations described above that make use of braided
or counter-wound filaments 6a or filament bundles 6b have enhanced
torsional strength. However, these configurations also have
increased total or "effective" diameters. Depending on the intended
application of the invention, particular configurations may be
preferred.
[0074] The multi-filament or braided filament bundle is
rotationally stable, i.e., it does not have a preferred bending
direction as does the prior art ribbon configuration. Therefore, if
multi-filament or braided filament bundle is placed in a tortuous
anatomy such as that depicted in FIG. 5, the guide wire will permit
the distal tip of the guide wire to be oriented in any direction in
a controllable fashion. The distal tip of the guide wire will
advantageously have a 1:1 response or a substantially 1:1 torque
response. Moreover, the guide wire eliminates the "whipping" motion
that heretofore accompanied guide wires that utilized a ribbon
structure at the distal tip.
[0075] The filament or braided filament bundle is more flexible
than a solid structure of equivalent diameter, yet retains
approximately the same tensile strength as a solid structure of the
same equivalent diameter. This characteristic advantageously allows
for a filament or braided-filament bundle to have both high
flexibility and high tensile strength. Unlike the prior art ribbon
configuration, however, the filament or braided filament bundle is
rotationally stable. Consequently, a guide wire making use of the
multifilament bundle in the distal tip portion C can be highly
flexible, have high tensile integrity, and be highly steerable,
even in tortuous vasculature. In one preferred aspect of the
invention, the distal tip portion of the guide wire has
substantially uniform stiffness in all radial directions.
[0076] FIG. 13 illustrates a medical device according to another
preferred aspect of the invention. Balloon catheter 80 includes an
elongate tubular member 82 having a proximal end, a distal region
and a lumen, balloon 86 located on the distal region, inflation
lumen 84 communicating with the balloon and extending proximally
from balloon 86, and core wire 93 disposed within the lumen. The
distal region of balloon catheter 80 further includes braided
filament 88 that extends distally from the distal region of
elongate tubular member 82. Braided filament 88 may be coupled to
elongate tubular member 82 and/or core wire 93 by solder joint 83.
Braided filament 88 terminates at the distal tip 89. The braided
filament 88 may be about 2 cm in length, alternatively about 3 cm
in length, alternatively about 4 cm in length, alternatively about
5 cm in length, alternatively about 6 cm in length, alternatively
about 7 cm in length, alternatively about 8 cm in length. Balloon
catheter 80 further includes coil 87 that surrounds at least a
portion of braided filament 88 and terminates at the distal tip 89.
The distal tip 89 may include an end cap 90 such as a weld, braze,
solder, adhesive, or the like to secure the distal most ends of the
braided filament 88. Distal tip 89 may have a substantially
hemispherical or round shape; alternatively, it could have a
tapered or pointed shape. Balloon 86 may be either be an occlusion
balloon or a dilatation balloon.
[0077] In use, the balloon catheter may be advanced into a vessel
containing a lesion. Where the balloon is a dilatation balloon, the
balloon may be located at the site of the lesion. The balloon may
then be expanded to dilate the lesion. Where the balloon is an
occlusion balloon, after the balloon is advanced into the vessel
containing the lesion, the balloon may be located distal the
lesion. A catheter having a dilatation balloon may then be advanced
over the elongate tubular member and the dilatation balloon may
then be expanded to dilate the lesion. Alternatively, the catheter
may include a stent disposed about the dilatation balloon.
[0078] FIG. 14 illustrates a medical device according to another
preferred aspect of the invention. Filter catheter 100 includes an
elongate tubular member 102 having a proximal end, a distal region,
expandable filter 104 located on the distal region, and actuation
mechanism 105 operable to expand the filter. Expandable filter 104
includes a plurality of struts 106, at least a portion of which is
covered by porous material 111, such as a mesh material. The distal
region of filter catheter 100 further includes braided filament 108
that extends distally from the distal region of elongate tubular
member 102. Braided filament 108 may be coupled to the distal end
of elongate tubular member 102 through solder joint 103. Braided
filament 108 terminates at the distal tip 109. The braided filament
108 may be about 2 cm in length, alternatively about 3 cm in
length, alternatively about 4 cm in length, alternatively about 5
cm in length, alternatively about 6 cm in length, alternatively
about 7 cm in length, alternatively about 8 cm in length. Filter
catheter 100 further includes coil 107 that surrounds at least a
portion of braided filament 108 and terminates at the distal tip
109. The distal tip 109 may include an end cap 110 such as a weld,
braze, solder, adhesive, or the like to secure the distal most ends
of the braided filament 108. Distal tip 109 may have a
substantially hemispherical or round shape; alternatively it could
have a tapered or pointed shape.
[0079] In use, the filter catheter may be advanced into a vessel
containing a lesion such that the expandable filter is located
distal the lesion. The actuation mechanism can then be operated to
expand the expandable filter. Once the filter is expanded, a
catheter having a dilatation balloon could be advanced over the
elongate tubular member of the filter catheter and the dilatation
balloon could be expanded at the site of the lesion. Additionally
or alternatively, a catheter having a stent could be advanced over
the elongate tubular member and the stent could be expanded at the
site of the lesion.
[0080] While embodiments of the present invention have been shown
and described, various modifications may be made without departing
from the scope of the present invention. The invention, therefore,
should not be limited,.except to the following claims, and their
equivalents.
* * * * *