U.S. patent application number 13/779149 was filed with the patent office on 2013-07-04 for over-the-wire interlock attachment/detachment mechanism.
This patent application is currently assigned to W.L. GORE & ASSOCIATES, INC.. The applicant listed for this patent is W.L. GORE & ASSOCIATES, INC.. Invention is credited to Sean T. Forde, Steven W. Opolski.
Application Number | 20130172977 13/779149 |
Document ID | / |
Family ID | 26933905 |
Filed Date | 2013-07-04 |
United States Patent
Application |
20130172977 |
Kind Code |
A1 |
Forde; Sean T. ; et
al. |
July 4, 2013 |
OVER-THE-WIRE INTERLOCK ATTACHMENT/DETACHMENT MECHANISM
Abstract
The over-the-wire interlock attachment/detachment mechanism
includes a cylindrical lock receiving section of a small diameter
attached to an implantable medical device such as a blood clot
filter, a stent, or a septal occluder. This cylindrical lock
receiving section has a plurality of spaced, curved cutouts to
receive both the guide fingers and contoured locking fingers formed
on a cylindrical locking section. The locking fingers are angled
outwardly from the cylindrical body of the cylindrical locking
section, and are moved inwardly into engagement with the curved
cutouts of the cylindrical lock receiving section by a sheath which
slides over the cylindrical locking section or other suitable
operator.
Inventors: |
Forde; Sean T.; (Watertown,
MA) ; Opolski; Steven W.; (Carlisle, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
W.L. GORE & ASSOCIATES, INC.; |
Flagstaff |
AZ |
US |
|
|
Assignee: |
W.L. GORE & ASSOCIATES,
INC.
Flagstaff
AZ
|
Family ID: |
26933905 |
Appl. No.: |
13/779149 |
Filed: |
February 27, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11200628 |
Aug 9, 2005 |
8398694 |
|
|
13779149 |
|
|
|
|
09977971 |
Oct 17, 2001 |
6936058 |
|
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11200628 |
|
|
|
|
60241005 |
Oct 18, 2000 |
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Current U.S.
Class: |
623/1.11 ; 606/1;
606/200 |
Current CPC
Class: |
A61B 2017/1205 20130101;
A61B 17/12022 20130101; A61F 2230/005 20130101; A61F 2/01 20130101;
A61B 2017/00575 20130101; A61F 2/95 20130101; A61B 17/00234
20130101; A61F 2230/0067 20130101; A61B 2017/00619 20130101; A61F
2002/9528 20130101; A61F 2/962 20130101; A61F 2002/018 20130101;
A61F 2/011 20200501; A61B 17/0057 20130101; A61F 2002/9505
20130101 |
Class at
Publication: |
623/1.11 ; 606/1;
606/200 |
International
Class: |
A61B 17/00 20060101
A61B017/00; A61F 2/962 20060101 A61F002/962; A61B 17/12 20060101
A61B017/12 |
Claims
1. A method for retrieving a medical implant comprising: accessing
a medical implant using a locking mechanism comprising a locking
arm, wherein the locking mechanism is enclosed in a sheath, and the
implant comprises a cutout section; sliding the sheath away from
the locking mechanism to allow the locking arm to angle outwardly
from a longitudinal axis of the locking mechanism; positioning the
locking arm over the cutout section of the implant; sliding the
sheath back over the locking mechanism to lock the locking arm in
the cutout section and thereby locking the implant; and retrieving
the locking mechanism with the implant.
2. The method of claim 1 wherein the accessing step comprises
accessing the implant with a guidewire and passing the locking
mechanism over the guidewire.
3. The method of claim 1 wherein the implant is selected from the
group consisting of an occluder, a filter, and a stent.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of U.S.
application Ser. No. 11/200,628 filed Aug. 9, 2005, now pending;
which is a divisional application of U.S. application Ser. No.
09/977,971 filed Oct. 17, 2001, now issued as U.S. Pat. No.
6,936,058; which claims the benefit under 35 USC .sctn.119(e) to
U.S. Application Ser. No. 60/241,005 filed Oct. 18, 2000, now
expired. The disclosure of each of the prior applications is
considered part of and is incorporated by reference in the
disclosure of this application.
BACKGROUND OF THE INVENTION
[0002] In recent years, a number of medical devices have been
designed which are adapted for compression into a small size to
facilitate introduction into the heart or a vascular passageway and
which are subsequently expandable. These devices, among others,
include septal occluders, stents and free standing filters which
expand and are held in position by engagement with the wall of an
organ or vessel. It has been found to be advantageous to form such
devices of a shape memory material having a first, relatively
pliable low temperature condition and a second, relatively rigid
high-temperature condition. By forming such devices of temperature
responsive material, the device in a flexible and reduced stress
state may be compressed to fit within the bore of a delivery
catheter when exposed to a temperature below a predetermined
transition temperature, but at temperatures at or above the
transition temperature, the device expands and becomes relatively
rigid.
[0003] Originally, these implantable medical devices were intended
to permanently remain in place, but recently it has become
advantageous to retrieve the previously implanted device.
[0004] The development of removable implantable medical devices
such as septal occluders, stents and filters which expand and are
held in position by engagement with the wall of an organ or vessel
has led to the development of intra vascular snares to retrieve
these foreign bodies, usually from the peripheral vessels of the
cardiovascular system. Single loop snares, such as those shown by
U.S. Pat. No. 3,828,790 to Curtiss et al. and U.S. Pat. No.
5,171,233 to Amplatz et al. are commonly used snares. The Amplatz
snare consists of a super-elastic nitinol cable with a
single-formed loop. Because of the snare's super elastic
construction, the loop can be introduced through small lumen
catheters without risk of deformation. The loop is formed at
approximately 90.degree. to a cable, and this allows for the user
to advance the loop over a foreign body and ensnare it by closing
the loop with a small catheter. The foreign body is removed from
the vasculature by withdrawing the device into a guiding catheter
or vascular sheath.
[0005] In an attempt to provide a snare with improved cross
sectional vessel coverage, multiloop snares such as those shown by
U.S. Pat. No. 5,098,440 to Hillstead and U.S. Pat. No. 6,099,534 to
Bates have been developed. These snares include loops which are
joined only at their proximal ends to a shaft, and otherwise are
not joined at any point between the shaft and the distal ends of
the loops. This provides the advantage over single loop snares of
enhanced cross sectional vessel coverage, and the free distal ends
of the loops can be brought together to engage multiple surfaces of
an intravascular medical device to be removed.
[0006] The problem with known snare recovery devices is that they
are difficult to advance over a medical implant device and require
skilled manipulation to retrieve an implanted device. Once the
medical implant device is engaged by a recovery snare, there is no
assurance that the device will not slip out of the snare during the
recovery process.
[0007] It is particularly difficult to remove medical implants from
the heart, such as septal occluders, with known snare recovery
devices. Such snare recovery devices normally require appropriate
sizing to the vasculature in order to facilitate successful
ensnarement, and the geometry of multi loop snares is difficult to
maintain during delivery. The relative position of the loops can
change, both within a catheter or delivery tube and within a
vessel, and the loops can actually become displaced or entangled
during delivery.
SUMMARY OF THE INVENTION
[0008] A primary object of the present invention is to provide a
novel and improved over-the-wire interlock attachment/detachment
mechanism adapted to engage and positively lock on to an implanted
medical device.
[0009] Another object of the present invention is to provide a
novel and improved over-the-wire interlock attachment/detachment
mechanism which automatically aligns to form, an interlock
attachment with an implanted medical device.
[0010] A farther object to the present invention is to provide a
novel and improved over-the-wire interlock attachment/detachment
mechanism well adapted for use with over-the-wire implanted medical
devices.
[0011] Yet another object of the present invention is to provide a
novel and improved over-the-wire interlock attachment/detachment
mechanism which includes a cylindrical locking section for
engagement with a cylindrical lock receiving section connected to
the medical implant.
[0012] A further object of the present invention is to provide a
novel and improved over-the-wire interlock attachment/detachment
mechanism which includes no overlapping components and which
maintains a low profile configuration during passage through a
vessel and/or catheter.
[0013] These and other objects of the present invention are
achieved by providing a cylindrical lock receiving section of a
small diameter attached to an implantable medical device such as a
blood clot filter, a stent, or a septal occluder. This cylindrical
lock receiving section has a plurality of spaced, curved cutouts to
receive both the guide fingers and contoured locking fingers formed
on a cylindrical locking section. The locking fingers are angled
outwardly from the cylindrical body of the cylindrical locking
section, and are moved inwardly into engagement with the curved
cutouts of the cylindrical lock receiving section by a sheath which
slides over the cylindrical locking section, or by another suitable
operator which can be activated to move the fingers inwardly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a perspective view of the over-the-wire interlock
attachment/detachment mechanism of the present invention with the
control sheath shown in section;
[0015] FIG. 2 is a perspective view of an over-the-wire free
standing filter with the cylindrical lock receiving section for the
over-the-wire interlock attachment/detachment mechanism of FIG.
1;
[0016] FIG. 3 is a perspective view of the partially engaged
locking and lock receiving sections for the over-the-wire interlock
attachment/detachment mechanism of FIG. 1;
[0017] FIG. 4 is a perspective view of the engaged locking and lock
receiving sections for the over-the-wire interlock
attachment/detachment mechanism of FIG. 1;
[0018] FIG. 5 is a second embodiment of a locking section for the
over-the-wire interlock attachment/detachment mechanism of the
present invention; and
[0019] FIG. 6 is a third embodiment of a locking section for the
over-the-wire interlock attachment/detachment mechanism of the
present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] Referring to FIG. 1, the over-the-wire interlock
attachment/detachment mechanism of the present invention indicated
generally at 10 is adapted for movement along a conventional
guidewire 12 such as a 0.014'' guidewire. The over-the-wire
interlock attachment/detachment mechanism includes a male locking
section 14, a female lock receiving section 16, and a tubular
sheath 18 dimensioned to slide over the male and female sections.
Preferably, the female section 16 is secured to an implantable
medical device 20 such as a septal occluder, a filter or stent to
be released in the heart or a blood vessel or other vessel of the
human body or to be retrieved or repositioned within the heart or
vessel.
[0021] The male locking section 14 includes a tubular body 22 which
defines an open ended central chamber 24 through which the
guidewire 12 passes. Projecting outwardly from the forward end of
the tubular body 22 are one or more elongate guide fingers 26.
These guide fingers are straight, elongate pins with arcutely
shaped ends 28, and two such guide fingers are shown in FIG. 1
although more than two can be provided. The outer surface of each
guide finger is preferably coextensive with the outer surface of
the tubular body 22.
[0022] Also projecting outwardly from the forward end of the
tubular body 22 are one or more flexible, elongate locking arms 30
which are substantially equal in Width to the width of the guide
fingers 26. Underlying each of the locking arms is a slot 32 formed
in the tubular body to receive the locking arm. When unconfined,
each locking arm is formed to angle outwardly beyond the outer
surface of the tubular body 22.
[0023] A shaped locking member 34 is formed at the end of each
locking arm. Preferably, this locking member, which extends
laterally from at least one side of the locking arm, is circular in
shape, but other shapes which extend laterally from the locking arm
including but not limited to an ellipse, a "T", a rectangle, a
square, a hook, a triangle or an "L" can be used. A circular
locking member facilitates engagement with the lock receiving
section 16. The guide fingers and locking arms are equally spaced
around the tubular body 22. They are preferably equal in number,
and although two of each are shown, more can be used.
[0024] The female lock receiving section 16 includes a tubular body
36 which defines an open ended central chamber 38 for receiving the
guidewire 12. The tubular body 36 is substantially equal in
diameter to the tubular body 22 so that the two are coextensive
when the male locking section is engaged with the female lock
receiving section.
[0025] The female lock receiving section includes a plurality of
shaped locking cutouts 40 which are shaped to conform to and
receive the shaped locking members 34. The number of shaped locking
cutouts 40 is equal to the number of guide fingers 26 and locking
arms 30. Extending into each of the shaped locking cutouts 40 is a
straight, open ended, cutout entry section 42 which is formed to
receive either a guide finger 26 or a locking arm 30.
[0026] The shaped locking cutouts 40 and open ended entry cutout
sections 42 are equally spaced around the tubular body 36 to
conform to the spacing of the guide fingers 26 and locking arms 30.
Outwardly projecting spacer sections 44 extend outwardly between
adjacent shaped cutouts and open ended entry cutout sections and
each terminate in inclined outer end surfaces 46 and 48 which form
an apex 50. Each inclined outer surface angles downwardly toward an
open ended entry cutout section 42 and the inclined outer end
surface 46 of a spacer section 44 forms with the inclined outer end
surface 48 of an adjacent spacer section an enlarged outwardly
tapered opening 52 for each open ended cutout section.
[0027] The female lock receiving section 16 is secured to one end
of a medical implant 20, which can be an over the wire device such
as a septal occluder. For purpose of illustration, the female lock
receiving section is shown with the over-the-wire free standing
filter 54. The free standing filter 54 has a filter body with an
elongate guidewire receiving member 56 extending centrally
therethrough to define an open ended channel configured to receive
a plurality of different sized guidewires. An expandable and
contractible frame 58 surrounds the elongate guidewire receiving
member and is connected at a proximal end to the elongate guidewire
receiving member. A porous embolic capturing unit 60 has an open
end 62 connected to the frame and a closed end 64 connected to the
elongate guidewire receiving member which extends through the
porous embolic capturing unit.
[0028] FIGS. 1, 3 and 4 disclose the manner in which the
over-the-wire interlock attachment/detachment mechanism 10 is
operable to positively engage and remove a medical implant 20 from
a body organ or vessel. The male locking section 14 is enclosed
within the sheath 18 so that the locking arms 30 are forced into
the slots 32 and do not project outwardly beyond the periphery of
the male locking section. In this configuration, the male locking
section is passed along the wire 12 until it is positioned in close
proximity to the female lock receiving section 16. At this point,
the sheath 18 is drawn back to permit the locking arms 30 to angle
outwardly from the male locking section 14. The male locking
section is then moved toward the female lock receiving section 16
until the guide fingers 26 engage the outer end surface 46 or 48 of
a spacer section 44. As the male locking section continues to move
toward the female lock receiving section, each guide finger will be
guided by an inclined outer end surface 46 or 48 into an open ended
cutout entry section 42 which then guides the guide finger into the
associated shaped cutout 40. The over-the-wire interlock
attachment/detachment mechanism is now in the configuration
illustrated in FIG. 3. It will be noted that when the guide fingers
move into the open ended cutout entry sections 42, they position
the locking arms 30 and the locking members 34 above and in
alignment with open ended cutout sections 42 and their associated
shaped cutouts 40. Now, shown in FIG. 4, the tubular sheath 18 is
moved forwardly over the tubular bodies 22 and 36 to force the
locking members 34 into the shaped cutouts 40 and positively engage
the male locking section 14 with the female lock receiving section
16.
[0029] Once a positive engagement has been established between the
male locking section and female lock receiving section, the
over-the-wire interlock attachment/detachment mechanism can be
drawn back over the wire 12 to remove the medical implant 20.
Because of the positive locking engagement, forces present on the
medical implant as it is withdrawn will not result in detachment
from the over-the-wire interlock attachment/detachment mechanism.
This is very important for medical implants such as the removable
filter 54 where hooks 58 must be withdrawn from the wall of the
vessel.
[0030] It is often difficult to accurately position a medical
implant within a vessel without disconnecting or misaligning the
implant relative to the positioning device. This problem is
rectified by the over-the-wire interlock attachment/detachment
mechanism 10. The medical implant 20 with an attached female lock
receiving section 16 is positively locked to the male locking
section 14 in the manner shown by FIG. 4 before it is moved over
the wire 12 into position within a body vessel. The positive
locking action between the male locking section and female lock
receiving section facilitates accurate positioning of the medical
implant within a vessel without misorientation or the likelihood of
a disconnect. Once the implant device is positioned, the sheath 18
can be moved back as shown in FIG. 3 allowing the locking arms 30
to spring outwardly to disengage the locking members 34 from the
shaped cutouts 40. Now the male locking section 14 can be drawn
back over the wire 12 away from the female lock receiving section
16.
[0031] The sheath 18 may be replaced by other operating mechanisms
capable of moving the locking arms 30 into the slots 32. For
example, elongate tethers attached to the ends of the locking arms
which extend back through the central chamber 24 might perform this
function.
[0032] The male locking section 14 can be modified as shown in
FIGS. 5 and 6 to provide a flexible end section 68 adjacent to the
elongate guide fingers 26 and elongate locking arms 30. By
providing a flexible section 68 in the body 22 proximal to the
guide fingers and locking arms, it becomes easier to align the
guide fingers, locking arms and locking members 34 with the cutouts
in the female lock receiving section 16. The flexible section 68
can be formed in a variety of ways. For example, a spring section
can be welded or bonded to the body 22 between the main portion of
the body and the guide fingers and locking arms to form the
flexible section 68. Ideally, as shown in FIG. 5, the body 22 is
formed with a unitary spring section 68 by cutting the body in a
spiral to create a helical spring 70. This can be done with a laser
which can also be used to shape the guide fingers, locking arms and
locking members in the tubular body 22.
[0033] Alternatively, as shown in FIG. 6, a flexible, tubular
polymer section 72 can be formed between the main portion of the
body 22 and the guide fingers and locking arms to provide the
flexible section 68.
* * * * *