U.S. patent number RE34,695 [Application Number 07/968,236] was granted by the patent office on 1994-08-16 for torsionally stabilized guide wire with outer jacket.
This patent grant is currently assigned to Advanced Cardiovascular Systems, Inc.. Invention is credited to Lambert J. Diettrich, Craig E. Mar, David W. Morrison.
United States Patent |
RE34,695 |
Mar , et al. |
August 16, 1994 |
Torsionally stabilized guide wire with outer jacket
Abstract
Torsionally stabilized guide wire for use in larger vessels of
the vascular system. A relatively flexible helical coil is
positioned over the distal end portion of an elongated shaft which
increases in flexibility toward its distal end. The coil is affixed
to the shaft at the proximal and distal ends of the coil and at an
intermediate point near the distal end. A jacket having an outer
diameter substantially equal to the outer diameter of the coil
covers the shaft between the proximal end of the shaft and the
proximal end of the coil. In one disclosed embodiment, the jacket
is formed by heat shrinking a tubular sleeve of polyethylene about
the shaft.
Inventors: |
Mar; Craig E. (Fremont, CA),
Diettrich; Lambert J. (Danville, CA), Morrison; David W.
(San Jose, CA) |
Assignee: |
Advanced Cardiovascular Systems,
Inc. (Santa Clara, CA)
|
Family
ID: |
27043358 |
Appl.
No.: |
07/968,236 |
Filed: |
October 29, 1992 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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471226 |
Jan 26, 1990 |
|
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Reissue of: |
856492 |
Apr 25, 1986 |
04721117 |
Jan 26, 1988 |
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Current U.S.
Class: |
600/585;
604/528 |
Current CPC
Class: |
A61M
25/09033 (20130101); A61M 2025/09083 (20130101) |
Current International
Class: |
A61B
5/00 (20060101); A61B 005/00 () |
Field of
Search: |
;128/657,772
;604/95,164,170,280,282 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Shay; Randy C.
Attorney, Agent or Firm: Crosby, Heafey Roach & May
Parent Case Text
.Iadd.This is a continuation of the application Ser. No. 07/471,226
which was filed on Jan. 26, 1990, now abandoned. .Iaddend.
Claims
We claim:
1. In a guide wire for use in the vascular system: an elongated
shaft having a relatively flexible distal end portion, a helical
coil extending over the distal end portion of the shaft and a
substantial portion of the shaft proximal to the relatively
flexible distal end portion, and helical coil being affixed to the
shaft at its ends and at a point between its ends, and a jacket of
polyethylene heat shrunk about the shaft proximally of the helical
coil and having a thickness corresponding to the thickness of the
wire which forms the coil and an outer diameter substantially equal
to the outer diameter of the coil.
2. The guide wire of claim 1 including a tip of radiopaque material
at the distal end of the shaft.
3. The guide wire of claim 1 wherein the helical coil is coated
with Teflon.
4. The guide wire of claim 1 wherein the distal end portion of the
shaft decreases in cross-sectional dimension toward the distal end
of the shaft.
5. The guide wire of claim 4 wherein the cross-sectional dimension
of the distal end portion decreases in discrete steps.
6. The guide wire of claim 1 wherein the windings toward the distal
end of the coil are spread apart for greater flexibility and ease
of shaping.
7. The guide wire of claim 1 wherein one end of the coil is bonded
to the shaft by a cyanoacrylate adhesive.
8. In a guide wire for use in the vascular system: an elongated
shaft having a distal end portion of progressively smaller
cross-sectional dimension and increasing flexibility extending for
a distance on the order of 10-30% of the length of the shaft, a
relatively flexible helical coil positioned coaxially of the shaft
and extending from a point proximal to the midpoint of the shaft to
the distal end of the shaft with the ends of the coil being affixed
to the shaft, and a tubular jacket covering the shaft proximally of
the coil and having a thickness substantially equal to the
thickness of the wire forming the coil and an outer diameter
substantially equal to the outer diameter of the coil.
9. The guide wire of claim 8 wherein the helical coil is also
affixed to the shaft at a point between the ends of the coil.
10. The guide wire of claim 8 including a tip of radiopaque
material at the distal end of the shaft.
11. The guide wire of claim 8 wherein the tubular jacket is
fabricated of a polyethylene tubing which is heat shrunk about the
shaft.
12. The guide wire of claim 8 wherein the tubular jacket is
fabricated of Teflon.
13. The guide wire of claim 8 wherein the helical coil is coated
with Teflon.
14. The guide wire of claim 8 wherein the distal end portion of the
shaft has a plurality of sections of progressively smaller
diameter, and a flattened tip portion of rectangular
cross-section.
15. The guide wire of claim 8 wherein the windings of the coil
toward the distal end of the shaft are spread apart for greater
flexibility and ease of shaping.
16. The guide wire of claim 8 wherein the proximal end portion of
the coil is bonded to the shaft by a cyanoacrylate adhesive.
.Iadd.
17. In a guide wire for use in the vascular system: an elongated
shaft having a relatively flexible distal end portion, a helical
coil extending over the distal end portion of the shaft and a
substantial portion of the shaft proximal to the relatively
flexible distal end portion, said helical coil being affixed to the
shaft at its ends and at a point between its ends and a plastic
jacket heat shrunk about the shaft proximally of the helical coil
and having a thickness corresponding to the thickness of the wire
which forms the coil and an outer diameter substantially equal to
the outer diameter of the coil. .Iaddend.
Description
This invention pertains generally to the insertion of elements such
as catheters into the vascular system, and more particularly to a
guide wire and method of manufacturing the same for use in larger
vessels as, for example, in the arms, the legs and the carotid
arteries.
Guide wires employed in coronary angioplasty are of relatively
small diameter because of the relatively small size of the blood
vessels and the luminal openings of the dilatation catheters which
pass over the guide wires. To facilitate steering or placement
within the cardiovascular system, a guide wire should be both
relatively flexible toward its distal end and relatively rigid from
a torsional standpoint over its entire length. These two desirable
properties are somewhat inconsistent and difficult to achieve in
practice. Examples of guide wires intended primarily for use in
coronary angioplasty are found in U.S. Pat. Nos. 4,554,929 and
4,545,390.
While guide wires designed for coronary angioplasty can, at least
in theory, also be employed in the peripheral organs such as the
arms and legs, they may not have sufficient torsional rigidity for
use in such applications. Another problem with guide wires and
dilatation catheters is blood loss between the guide wire and the
luminal wall of the catheter. Also, it is difficult to track a
catheter with a relatively large luminal opening over a guide wire
of relatively small diameter to a desired location. Ideally, the
guide wire should fit closely within the luminal opening and
loosely enough to permit the catheter to move freely along the
wire, a result which is often difficult to achieve in practice.
It is in general an object of the invention to provide a new and
improved guide wire.
Another object of the invention is to provide a guide wire in which
the guide wire has both high torsional rigidity and good
flexibility.
Another object of the invention is to provide a guide wire in which
the guide wire fits closely within a dilation catheter and also
allows the catheter to be advanced freely.
Another object of the invention is to provide a guide wire in which
the guide wire is particularly suitable for use in larger
vessels.
These and other objects are achieved in accordance with the
invention by providing a guide wire in which a relatively flexible
helical coil is positioned over the distal end portion of an
elongated shaft which increases in flexibility toward its distal
end. The coil also increases in flexibility toward its distal end
and is affixed to the shaft at its proximal and distal ends and at
an intermediate point near the distal end. Between the proximal end
of the shaft and the proximal end of the coil, the shaft is covered
with a jacket having an outer diameter substantially equal to the
outer diameter of the coil. In one disclosed embodiment, the jacket
is formed by heat shrinking a tubular sleeve of polyethylene about
the shaft.
The single FIGURE of drawing is an enlarged, fragmented
longitudinal sectional view of one embodiment of a guide wire
according to the invention.
The guide wire comprises an elongated mandrel or shaft 11 having a
relatively rigid proximal end portion and a relatively flexible
distal end portion. The distal end portion increases in flexibility
toward the distal end. In the embodiment illustrated, the shaft has
a generally circular cross-section, and the distal end portion has
sections 12, 13 of progressively smaller diameter and a flattened
tip section 14 of generally rectangular cross-section. Relatively
short conically tapered sections 16, 17 provide smooth transitions
between the sections of different diameter. Alternatively, the
distal end portion can have a single continuous taper rather than a
series of discrete steps in diameter.
In one presently preferred embodiment, the shaft comprises a
stainless steel wire which is ground by a centerless grinding
process to form the sections of different diameter. Flattened
section 14 is formed by rolling the distal tip of the wire after it
is ground to the diameter of section 13.
The dimensions of the shaft are selected to provide the desired
properties for the guide wire. The proximal end portion is
generally on the order of 10-30% of the overall length of the
shaft. In one example of a guide wire for use in the peripheral
organs, the proximal end of the shaft has a diameter of 0.020 inch,
section 12 has a diameter of 0.013 inch, section 13 has a diameter
of 0.004 inch, and section 14 has a thickness of 0.002 inch. In
this example, the shaft has an overall length on the order of
145-150 cm, section 12 has a length of about 12 cm, section 13 has
a length of about 2 cm, and section 14 has a length of about 3 cm.
Each of the transitional sections 16, 17 has a length of about 3-6
cm. For a more flexible guide wire, one or more of the sections can
be reduced in diameter, or one of the sections of smaller diameter
can be increased in length.
The properties of the guide wire can also be changed by employing a
greater or lesser number of sections in the distal end portion of
the shaft. For example, a section having a diameter of 0.015 inches
might be added between the proximal end portion and section 12 in
the example given above. This additional section might, for
example, have a length on the order of 25 cm.
A relatively flexible helical coil 19 is positioned coaxially of
the distal end portion of the shaft. The coil extends from a point
prior to the midpoint of the shaft to the distal end of the shaft.
The proximal end of the coil is affixed to the shaft by suitable
means such as a band of cyanoacrylate adhesive 21, and the distal
end of the coil is affixed to the distal end of the shaft. A tip 22
of radiopaque material such as gold is provided at the distal end
of the coil, and in the embodiment illustrated, the distal ends of
the coil and shaft are held together by the opaque material.
In one presently preferred embodiment, coil 19 is fabricated of a
stainless steel wire coated with Teflon. The inside diameter of the
coil corresponds to the diameter of the proximal end portion of
shaft 11, and with a 0.020 inch shaft, the coil typically has an
outside diameter of 0.035 inch. The windings of the coil are
closely spaced except in the vicinity of tip section 14 where they
are spread apart for increased flexibility and easier shaping. The
spread portion of the windings extends about 2.5-3.5 cm back from
tip 22 and is aligned with the flattened tip section 14 of the
shaft or core 11. Helical coil 19 is also affixed to shaft 11 at an
intermediate point 23 near the distal end of the shaft. Point 23 is
spaced a short distance (e.g., 7-8 cm) from the distal end, and the
connection between the coil and shaft at this point is made by
suitable means such as brazing. This connection gives the coil an
increased torsional rigidity and isolates the tip portion from the
main body of the wire for greater flexibility when sharp bends are
encountered.
A tubular sleeve or jacket 26 is mounted on shaft 11 between the
proximal end of the shaft and the proximal end of coil 19. This
sleeve is preferably fabricated of a heat shrinkable material such
as polyethylene or Teflon, and it is shrunk tightly about the
shaft. The outside diameter of the jacket is substantially equal to
the outside diameter of the coil, thereby giving the jacket a
thickness substantially equal to the thickness of the wire forming
the coil, so that the guide wire has a substantially uniform
diameter throughout its entire length. In a guide wire having an
overall length of 145 cm, the jacket might be 45 cm long, and the
coil might be 100 cm, with the distal end of the jacket abutting
against the proximal end of the coil.
If desired, the tip portion of the guide wire beyond point 23 can
be bent to a desired shape to facilitate steering of the guide
wire.
In a presently preferred method of manufacture, shaft 11 is ground
and rolled to the desired configuration. The heat shrinkable
material is placed on the proximal end of shaft 11 and shrunk
tightly about the shaft to form jacket 26. Coil 19 is coated with
Teflon and placed over the distal end portion of the shaft. The
proximal end of the coil is affixed to the shaft by cyanoacrylate
adhesive 21, and the distal ends of the coil and shaft are brazed
together with the radiopaque material which forms tip 22. The coil
and shaft are also brazed together at the intermediate point
23.
The guide wire has a number of important features and advantages.
It has a relatively high torsional rigidity and a flexible tip
which is isolated from the main body of the wire. This facilitates
steering and placement of the wire in the vascular system. The wire
has a substantially uniform diameter throughout its entire length,
and this minimizes blood loss between the wire and the luminal wall
of a catheter advanced along the wire. The jacket on the proximal
end of the shaft reduces friction and enhances the appearance of
the guide wire.
It is apparent from the foregoing that a new and improved guide
wire and method of manufacturing the same have been provided. While
only certain presently preferred embodiments have been described in
detail, as will be apparent to those familiar with the art, certain
changes and modifications can be made without departing from the
scope of the invention as defined by the following claims.
* * * * *