U.S. patent application number 11/004445 was filed with the patent office on 2006-06-08 for apparatus and method for delivering fasteners during valve replacement.
Invention is credited to Michael J. Drews, Donnell W. Gurskis, Takashi Harry Ino.
Application Number | 20060122634 11/004445 |
Document ID | / |
Family ID | 36013387 |
Filed Date | 2006-06-08 |
United States Patent
Application |
20060122634 |
Kind Code |
A1 |
Ino; Takashi Harry ; et
al. |
June 8, 2006 |
Apparatus and method for delivering fasteners during valve
replacement
Abstract
A fastener delivery tool includes a loading chamber for
receiving a fastener having a pair of tines overlapping one another
to define a loop in a parent or relaxed state. A retaining member
retains the fastener in the loading chamber. The fastener delivery
tool also includes a tongue, pusher member, and an ejection track
communicating with the loading chamber. An actuator causes the
tongue to move to engage the tines of the fastener to transform the
fastener from the relaxed state to a constrained state defining a
U-shape. The actuator also causes the pusher member to release the
retaining member and advance the fastener down the ejection track
in the constrained state. The tool also includes a trigger for
ejecting the fastener completely from the ejection track. The
fastener may be used to secure a prosthetic heart valve or
components thereof into surrounding tissue, e.g., within a tissue
annulus.
Inventors: |
Ino; Takashi Harry; (San
Jose, CA) ; Drews; Michael J.; (Sacramento, CA)
; Gurskis; Donnell W.; (Belmont, CA) |
Correspondence
Address: |
Vista IP Law Group LLP
2040 MAIN STREET, 9TH FLOOR
IRVINE
CA
92614
US
|
Family ID: |
36013387 |
Appl. No.: |
11/004445 |
Filed: |
December 3, 2004 |
Current U.S.
Class: |
606/142 |
Current CPC
Class: |
A61B 17/068 20130101;
A61B 17/0644 20130101; A61B 2017/00862 20130101 |
Class at
Publication: |
606/142 |
International
Class: |
A61B 17/10 20060101
A61B017/10 |
Claims
1. A fastener delivery tool, comprising: a loading chamber for
receiving a fastener having a plurality of tines in a relaxed
state; a releasable retaining member for limiting movement of the
fastener within the loading chamber; an ejection track
communicating with the loading chamber; a handle including an
actuator; a tongue and a pusher member coupled to the actuator,
activation of the actuator advancing the tongue to engage the tines
so as to transform the fastener from the relaxed state to a
constrained state and advancing the pusher member to advance the
fastener from the loading chamber down the ejection track.
2. The fastener delivery tool of claim 1, further comprising a
trigger for ejecting the fastener distally from the ejection
track.
3. The fastener delivery tool of claim 1, wherein, in the relaxed
state, the tines of the fastener overlap one another to define a
loop, the retaining member being received in the loop for limiting
movement of the fastener, and, in the constrained state, the
fastener comprises a U-shape.
4. The fastener delivery tool of claim 3, wherein the ejection
track comprises side walls for constraining the fastener in the
U-shape as the fastener is advanced down the ejection track.
5. The fastener delivery tool of claim 4, wherein the tines are
exposed distally beyond the ejection track when the actuator is
activated without ejecting the fastener completely from the
ejection track.
6. The fastener delivery tool of claim 1, wherein the retaining
member comprises a movable release pin.
7. The fastener delivery tool of claim 6, wherein the release pin
is coupled to at least one of the tongue and the pusher member such
that the release pin releases the fastener after the actuator is
activated.
8. The fastener delivery tool of claim 1, further comprising a
staging section including a plurality of fasteners disposed
therein.
9. The fastener delivery tool of claim 8, wherein the plurality of
fasteners are carried by a cartridge receivable in the staging
section.
10. The fastener delivery tool of claim 1, the retaining member
being releasable upon engagement with a cam located on the pusher
member.
11. The fastener delivery tool of claim 1, wherein the fastener
includes two tines that overlap one another in the relaxed
state.
12. A fastener delivery tool, comprising: a loading chamber for
receiving at least one fastener having a pair of tines overlapping
one another in a relaxed state, the loading chamber including a
release pin on which said at least one fastener is loaded; an
ejection track communicating with the loading chamber; and an
actuator coupled to a tongue and a pusher member, activation of the
actuator causing the tongue to engage the plurality of tines to
transform the fastener from the relaxed state to a constrained
state and causing the pusher member to advance the fastener in the
constrained state from the loading chamber down the ejection
track.
13. The fastener delivery tool of claim 12, wherein the at least
one fastener has a U-shape in the constrained state.
14. The fastener delivery tool of claim 12, further comprising a
trigger for ejecting the at least one fastener from the ejection
track.
15. A method for delivering a fastener, comprising: restraining a
fastener within a delivery tool using a retaining member, the
fastener comprising a pair of tines; advancing a tongue in the
delivery tool relative to the restrained fastener to transform the
fastener from a relaxed state to a constrained state; releasing the
fastener from the retaining member while the fastener is in the
constrained state; advancing the fastener in the constrained state
distally within the delivery tool; and ejecting the fastener from
the delivery tool.
16. The method of claim 15, wherein the delivery tool carries a
plurality of fasteners therein.
17. The method of claim 16, further comprising loading a cartridge
into the delivery tool, the cartridge carrying the plurality of
fasteners.
18. The method of claim 15, wherein the tongue and fastener are
advanced successively upon activating an actuator.
19. The method of claim 15, wherein the constrained state comprises
a U-shaped fastener.
20. The method of claim 15, further comprising depressing a trigger
on the delivery tool to eject the fastener completely from the
delivery tool.
21. The method of claim 15, wherein the fastener is advanced
distally within the delivery tool in the constrained state by
depressing a lever on the delivery tool.
22. A method for securing a heart valve prosthesis within a tissue
annulus, comprising: restraining a fastener within a delivery tool
using a retaining member; advancing a tongue in the delivery tool
relative to the restrained fastener to transform the fastener from
a relaxed state to a constrained state; releasing the fastener from
the retaining member while the fastener is in the constrained
state; advancing the fastener in the constrained state distally
within the delivery tool; and ejecting the fastener from the
delivery tool through a component of a heart valve prosthesis into
the tissue annulus.
23. The method of claim 22, wherein the fastener includes a pair of
tines that overlap in the relaxed state to define a loop, the
retaining member being received in the loop to restrain the
fastener.
24. The method of claim 23, wherein the tongue is received in the
loop such that, as the tongue is advanced, the tongue moves the
tines into a U-shape in the constrained state.
25. The method of claim 22, wherein the fastener resiliently moves
towards the relaxed state after the fastener is ejected from the
from the delivery tool to capture tissue between the tines.
Description
FIELD OF THE INVENTION
[0001] The invention relates generally to apparatus and methods for
fastening devices to tissue or other devices, and, more
particularly, to apparatus and methods for delivering fasteners
during heart valve replacement, placement of other prostheses, or
repair of body organs in general and vascular surgery, such as
wound closure, anastomosis, hernia repair, and grafting procedures
for aneurysm repair.
BACKGROUND
[0002] Prosthetic heart valves have been used to replace defective
human valves in patients. A prosthetic valve generally includes a
sewing ring or suture cuff that may be attached to and/or extend
around a valve member. The sewing ring may be made from a
biocompatible fabric and/or other material through which a needle
and suture may pass. The sewing ring may be part of a single piece
prosthetic valve, or may be part of a multiple piece prosthetic
valve assembly.
[0003] In a typical aortic valve replacement procedure, the aorta
may be incised and the defective valve leaflets removed, leaving a
desired placement site that may include a fibrous tissue layer or
tissue annulus. Needles carrying sutures may be directed through
the fibrous tissue or desired placement site within the tissue
annulus to form an array of sutures. Free ends of the sutures may
be extended out of the thoracic cavity and laid, spaced apart, on
the patient's body.
[0004] The needles and sutures may then be threaded individually
through a sewing ring, typically delivering between ten and twenty
(12-20) sutures through the sewing ring. Once the sutures have been
directed through the sewing ring, the sutures may be pulled up
taught and the sewing ring may be slid over the sutures or
"parachuted" down into place adjacent the placement site tissue.
The sewing ring may then be secured in place by knot tying knots in
the sutures. This procedure is time consuming as doctors often use
three to ten knots per suture.
[0005] If the sewing ring is separate from a valve member of a
multiple component prosthesis, the valve member may be introduced
into the placement site, and secured to the sewing ring. The
sutures may be tied, not only to secure the sewing ring to the
biological mass and, but to secure the valve member to the sewing
ring (and consequently, to the tissue annulus).
[0006] During heart valve replacement procedures, the patient may
be on cardiopulmonary bypass (CPB), which may reduce the patient's
oxygen level and/or create non-physiological blood flow dynamics.
The longer a patient is on CPB, the greater the risk for long-term
or even permanent health damage. Existing suturing techniques
extend the duration of CPB and, consequently, increase the health
risks due to the patient. Furthermore, the fixturing force created
by suturing varies significantly from suture to suture, even for
the same medical professional.
[0007] Sewing rings can also be tedious and time consuming to
secure to a valve orifice. To assemble multiple component heart
valves, for example, one component has to be sewn into another in
vivo, resulting in a complex and time consuming process. The
complexity of the procedure also provides a greater opportunity for
mistakes and requires a patient to be on cardiopulmonary bypass for
a lengthy period.
SUMMARY OF THE INVENTION
[0008] The invention is directed to apparatus and methods for
fastening devices to tissue or other devices, and, more
particularly, to apparatus and methods for delivering fasteners
during heart valve replacement. The invention may be deployed to
secure a prosthesis to surrounding tissue, or to secure one
prosthesis to another, or a portion of a prosthesis to a
coordinating prosthesis.
[0009] In accordance with one embodiment, a fastener delivery tool
is provided that includes a loading chamber for receiving a
fastener having a plurality of tines in a relaxed state. The tool
also includes a releasable retaining member for limiting movement
of the fastener within the loading chamber. An ejection track is
coupled to the loading chamber. A handle is provided that includes
a lever, and a tongue and pusher member coupled to the lever.
Movement of the lever advances the tongue to engage the tines so as
to transform the fastener from the relaxed state to a constrained
state. Movement of the lever also advances the fastener from the
loading chamber down the ejection track. A trigger is depressed to
eject the fastener from the tool.
[0010] In another embodiment, a method for delivering a fastener is
provided that includes providing a fastener delivery tool having a
fastener therein, the fastener including a pair of tines in a
relaxed state. The fastener is secured in the fastener delivery
tool using a releasable retaining member. A tongue is advanced in
the fastener delivery tool so as to transform the fastener from a
relaxed state to a constrained state while the fastener is secured
with the releasable retaining member. The retaining member is
released and the fastener is advanced in the constrained state
distally within the fastener delivery tool using a pusher member.
The fastener is ejected from the fastener delivery tool by
depressing an actuator.
[0011] In still another embodiment, a fastener delivery tool is
provided that includes a loading chamber for receiving at least one
fastener having a plurality of tines in a relaxed state, the
loading chamber including a release pin on which said at least one
fastener is loaded. The tool further includes an ejection track
communicating with the loading chamber and a lever coupled to a
tongue and a pusher member. The tongue is engageable with the
plurality of tines of the fastener so as to transform the fastener
from the relaxed state to a constrained state. The pusher member is
also engagable with a proximal end (e.g., a loop portion) of the
fastener so as to translate the fastener to a distal tip of the
tool. The fastener is then ejected by depressing a trigger or other
actuator.
[0012] In still another embodiment, a fastener delivery tool is
provided that includes a staging area or section in which a
plurality of fasteners are loaded. The fasteners may be loaded
individually or within a cartridge. Multiple fasteners may be
loaded into the tool, thereby permitting the user to eject or
"fire" multiple fasteners successively without having to reload
between ejections.
[0013] Other aspects and features of the present invention will
become apparent from consideration of the following description
taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a side view of a fastener delivery tool including
a cartridge containing a fastener being loaded into a loading
chamber of the fastener delivery tool.
[0015] FIG. 2(a) is a cross-sectional side view of the distal tip
of the fastener delivery tool shown in FIG. 1, showing the fastener
being loaded into the loading chamber (arrow A).
[0016] FIG. 2(b) is a cross-sectional top view of the distal tip of
the fastener delivery tool shown in FIG. 2(a).
[0017] FIG. 3(a) is a cross-sectional side view of the distal tip
of the fastener delivery tool shown in FIG. 1, showing initial
advancement of the cartridge retainer in the distal direction
(arrow B).
[0018] FIG. 3(b) is a cross-sectional top view of the distal tip of
the fastener delivery tool shown in FIG. 3(a).
[0019] FIG. 4(a) is a cross-sectional side view of the distal tip
of the fastener delivery tool shown in FIG. 1, showing complete
advancement of the cartridge retainer. As seen in FIG. 4(a), the
tines of the fastener are closer together due to advancement of the
cartridge retainer and coupled spreader.
[0020] FIG. 4(b) is a cross-sectional top view of the distal tip of
the fastener delivery tool shown in FIG. 4(a), showing initial
advancement of the tongue in the distal direction.
[0021] FIG. 5(a) is a cross-sectional side view of the distal tip
of the fastener delivery tool shown in FIG. 1, showing a tongue
advanced and entering a loop in the fastener.
[0022] FIG. 5(b) is a cross-sectional top view of the distal tip of
the fastener delivery tool shown in FIG. 5(a), showing the tongue
entering the loop in the fastener.
[0023] FIG. 6(a) is a cross-sectional side view of the distal tip
of the fastener delivery tool shown in FIG. 1, showing
transformation of the fastener into a constrained configuration
(i.e., the U-configuration). Advancement of the tongue in the
distal direction spreads the tines of the fasteners outward to form
the U-configuration.
[0024] FIG. 6(b) is a cross-sectional top view of the distal tip of
the fastener delivery tool shown in FIG. 6(a).
[0025] FIG. 7(a) is a cross-sectional side view of the distal tip
of the fastener delivery tool shown in FIG. 1, showing translation
of the fastener in the distal direction through advancement of a
pusher member. The tongue is also translated in the distal
direction along with the fastener to aid in maintaining the
U-configuration.
[0026] FIG. 7(b) is a cross-sectional top view of the distal tip of
the fastener delivery tool shown in FIG. 7(a), showing the tines of
the fastener projecting slightly beyond the distal-most end of the
fastener delivery tool.
[0027] FIG. 8(a) is a partial top down plan view of the fastener
delivery tool of FIG. 1 with the handle and lever removed for
clarity, and showing the loading chamber empty and ready for
receiving a cartridge containing a fastener.
[0028] FIG. 8(b) is a cross-sectional side view of the fastener
delivery tool of FIG. 8(a) taken along the line A-A.
[0029] FIG. 9(a) is a partial top down plan view of the fastener
delivery tool of FIG. 1 with the handle and lever removed for
clarity, and showing a fastener loaded in the loading chamber of
the fastener delivery tool.
[0030] FIG. 9(b) is a cross-sectional side view of the fastener
delivery tool of FIG. 9(a) taken along the line B-B.
[0031] FIG. 10(a) is a partial top down plan view of the fastener
delivery tool of FIG. 1 with the handle and lever removed for
clarity, and showing the cartridge retainer advanced distally to
secure the fastener via a spreader that draws the two tines of the
fastener closer to one another.
[0032] FIG. 10(b) is a cross-sectional side view of the fastener
delivery tool of FIG. 10(a) taken along the line C-C.
[0033] FIG. 11(a) is a partial top down plan view of the fastener
delivery tool of FIG. 1 with the handle and lever removed for
clarity, and showing the tongue advanced distally to drop into a
loop portion of the fastener.
[0034] FIG. 11(b) is a cross-sectional side view of the fastener
delivery tool of FIG. 11(a) taken along the line D-D.
[0035] FIG. 12(a) is a partial top down plan view of the fastener
delivery tool of FIG. 1 with the handle and lever removed for
clarity, and showing additional distal displacement of the tongue
to transform the fastener into the U-configuration.
[0036] FIG. 12(b) is a cross-sectional side view of the fastener
delivery tool of FIG. 12(a) taken along the line E-E.
[0037] FIG. 13(a) is a partial top down plan view of the fastener
delivery tool of FIG. 1 with the handle and lever removed for
clarity, and showing the fastener advanced distally such that the
two tines project slightly beyond the distal-most edge of the
ejection track of the fastener delivery tool.
[0038] FIG. 13(b) is a cross-sectional side view of the fastener
delivery tool of FIG. 13(a) taken along the line F-F.
[0039] FIG. 14(a) is a partial top down plan view of the fastener
delivery tool of FIG. 1 with the handle and lever removed for
clarity, and showing the ejection of the fastener from the ejection
track of the fastener delivery tool in a U-shaped
configuration.
[0040] FIG. 14(b) is a cross-sectional side view of the fastener
delivery tool of FIG. 14(a) taken along the line G-G.
[0041] FIG. 15(a) is a side view of a fastener delivery tool
according to one aspect of the invention, showing a cartridge being
loaded into the loading chamber of the device.
[0042] FIG. 15(b) is a side view of a fastener delivery tool shown
in FIG. 15(a), showing the cartridge retainer being advanced in the
distal direction (see arrow in FIG. 15(b)) over the cartridge.
[0043] FIG. 15(c) is a side view of a fastener delivery tool shown
in FIG. 15(a), showing the fastener being transferred from the
cartridge to the distal tip of the fastener delivery tool by
actuation of the lever.
[0044] FIG. 15(d) is a side view of a fastener delivery tool shown
in FIG. 15(a), showing compression of the ejection spring by
additional actuation of the lever.
[0045] FIG. 15(e) is a side view of a fastener delivery tool shown
in FIG. 15(a), showing the fastener delivery tool being fully
loaded and ready to deploy the fastener.
[0046] FIGS. 16(a) and 16(b) are top and side views of the distal
end of a fastener delivery tool, illustrating exemplary
configurations for an elongated distal tip for the tool.
[0047] FIG. 17(a) is a cross-section of a patient's body, showing a
prosthetic valve secured within a tissue annulus by exemplary
fasteners.
[0048] FIG. 17(b) is a cross-section of a patient's body, showing a
fastener delivery tool delivering a fastener through a portion of a
prosthetic valve into the surrounding tissue.
[0049] FIG. 17(c) is a radiograph showing a plurality of fasteners
deployed about the circumference of a prosthetic valve.
[0050] FIG. 18 is an alternative embodiment of a fastener delivery
tool that houses a plurality of fasteners.
DETAILED DESCRIPTION
[0051] Turning to the drawings, FIG. 1 shows a first embodiment of
a fastener delivery tool 2. The fastener delivery tool 2 includes a
distal tip 4 or snout from which one or more fastener(s) 6
(described in more detail below) may be ejected and a proximal end
8 that may be grasped by a user during positioning and delivery of
the fastener 6. The distal tip 4 and proximal end 8 of the tool 2
are separated by an elongated shaft 9. The fastener 6 may be stored
within a cartridge 7 that may be loaded into the fastener delivery
tool 2. The fastener delivery tool 2 also includes a proximally
located handle 10 having a lever 12 or other actuator that may be
used to deploy the fastener(s) 6. The handle 10 may be
ergonomically shaped such that a user may easily manipulate the
fastener delivery tool 2 into position. The handle 10 preferably
includes a spring-biased trigger 14, e.g., a depressible button
that may be used to eject the fastener 6 from the distal tip 4 of
the tool 2.
[0052] A cartridge retainer 16 is provided on the shaft 9 that may
be movable along the axial direction of the shaft 9. As described
more fully below, the cartridge retainer 16 may be used to retain
or otherwise secure the cartridge 7 for the subsequent deployment
steps of the fastener 6. In addition, the cartridge retainer 16 may
transform the fastener 6 into a partially constrained state.
[0053] FIGS. 2(a) and 2(b) illustrate the distal end of the
fastener delivery tool 2. As best seen in FIG. 2(a), a fastener 6
may be pre-loaded in a cartridge 7, e.g., in a parent or relaxed
state. In the relaxed state, the fastener 6 may include a pair of
overlapping tines 6(a), 6(b) (best seen in FIG. 2(b)) that may be
angled with respect to one another. The fastener 6 further includes
a loop portion 6(c), e.g., defined by ends of the tines 6(a), 6(b).
In an exemplary embodiment, the fastener 6 may be formed from an
elastic or superelastic material, such as a Nickel-Titanium alloy
(Nitinol). Additional information on exemplary embodiments of
fasteners that may be delivered using the tool 2 are disclosed in
co-pending application Ser. No. 10/681,700, filed Oct. 8, 2003, the
entire disclosure of which is expressly incorporated by reference
herein.
[0054] The fastener 6 may be secured or otherwise retained in a
groove 7(a) or slot in the cartridge 7. The cartridge 7 containing
the fastener 6 may be inserted (in the direction of arrow A in FIG.
2(a)) into a loading chamber 18 located at the distal end of the
shaft 9. During this loading process, the loop portion 6(c) of the
fastener 6 may be lowered over a retaining member 20. The retaining
member 20 may be movable between an engaged state (shown in FIG.
2(b)) and a disengaged state (described in more detail below).
Preferably, the retaining member 20 is biased in the engaged state
by a spring 22 or other biasing mechanism. The retaining member 20
advantageously secures the fastener 6 within the tool 2 during the
process of transforming the fastener 6 from the relaxed, parent
state to the constrained state (e.g., a U-shaped
configuration).
[0055] Still referring to FIGS. 2(a) and 2(b), the distal tip 4 of
the tool 2 includes an ejection track 23. The ejection track 23 is
connected to or otherwise communicates with the loading chamber 18.
During deployment of the fastener 6, the tines 6(a), 6(b) may be
forced into the U-shaped configuration and the fastener 6 may be
advanced from the loading chamber 18 and into the ejection track 23
(described in more detail below).
[0056] FIGS. 3(a) and 3(b) illustrate the next step involved in
deploying the fastener 6. As seen in FIGS. 3(a) and 3(b), the
cartridge retainer 16 may be advanced distally (shown by arrow B in
FIG. 3(a)). In one embodiment, the cartridge retainer 16 may be
advanced manually, for example, by depressing a finger on ridge
16(a). Alternatively, the cartridge retainer 16 may also be
advanced automatically, for example, through movement of the handle
10. The cartridge retainer 16 is coupled to a spreader 24 that may
engage the tines 6(a), 6(b) of the fastener 6. The spreader 24 may
include a slot or groove in which the fastener tines 6(a), 6(b) may
be received. Movement of the cartridge retainer 16 from the
position shown in FIGS. 3(a) and 3(b) to the position shown in
FIGS. 4(a) and 4(b) causes the spreader 24 also to move distally.
The spreader 24 contacts the tines 6(a), 6(b) of the fastener 6 and
causes the fastener 6 to transform into a partially constrained
state (best shown in FIG. 4(b).
[0057] FIGS. 5(a) and 5(b) illustrate the tongue 26 advancing in
the direction of arrow C shown in FIG. 5(b). As best seen in FIGS.
2(a) and 3(a), the tongue 26 includes one or more teeth 26(a). The
tongue 26 is advanced in the direction of arrow C and the one ore
more teeth 26(a) drop within the loop 6(c) of the fastener 6(c).
FIGS. 5(a) and 5(b) illustrate the teeth 26(a) within the fastener
loop 6(c). The tongue 26 is advanced further in the distal
direction as shown in FIGS. 6(a) and 6(b) to transform the fastener
6 from the partially constrained state to the fully constrained
state (i.e., the U-shaped configuration). The U-shaped
configuration is obtained by forcibly parting the tines 6(a), 6(b)
of the fastener 6 using the teeth 26(a) of the tongue 26, while
restraining the proximal end or loop portion 6(c) of the fastener
6.
[0058] FIGS. 7(a) and 7(b) illustrate the fastener 6 being advanced
through the ejection track 23. After the fastener 6 has assumed the
U-shaped configuration, the retaining member 20 may be moved from
the engaged state to the disengaged state. FIG. 7(a) illustrates
the retaining member 20 in the disengaged state. With the retaining
member 20 in the disengaged state, the fastener 6 may be free to
move distally down the ejection track 23. In one embodiment, the
retaining member 20 is moved from the engaged state to the
disengaged state by interaction of a cam structure 20(a) located on
the retaining member 20 with a pusher member 30 (see FIG. 7(a)).
For example, in the engaged state, the cam structure 20(a) on the
retaining member 20 may rest within a corresponding groove 30(a) in
the pusher member 30. When the pusher member 30 is advanced in the
distal direction, the cam structure 20(a) is forced out of the
groove 30(a) and forces the retaining member 20 to the disengaged
state.
[0059] Still referring to FIGS. 7(a) and 7(b), the pusher member 30
contacts a proximal end of the fastener 6 and pushes or advances
the fastener 6 down the ejection track 23. In one embodiment, the
pusher member 30 continues to advance the fastener 6 until the
fastener 6 reaches a position within the ejection track 23 shown in
FIGS. 7(a) and 7(b). In this position, the faster 6 is positioned
such that the tines 6(a), 6(b) project slightly from the
distal-most end of the tool 2.
[0060] This configuration may permit a physician or other user to
probe areas of tissue for the optimal insertion location. For
example, the physician may probe an area of tissue that may be
calcified or plaque-laden and not suitable for placement of a
fastener 6. In this regard, the physician may move instead to
another more potentially desirable location adjacent the calcified
location. Once the desired location is reached, the fastener 6 may
be completely ejected from the tool 2, e.g., by depressing the
trigger 14 (shown, for example, in FIG. 15(e)).
[0061] FIGS. 8(a) and 8(b) illustrate partial top and side views,
respectively, of the fastener delivery tool 2 with the handle 10
and lever 12 removed for clarity. In FIGS. 8(a) and 8(b), the
loading chamber 18 of the device is empty and the cartridge
retainer 16 is withdrawn in the proximal direction, permitting
loading of another cartridge 7 carrying a fastener 6 into the tool
2. FIGS. 9(a) and 9(b) illustrate a fastener delivery tool 2 loaded
with a single fastener 6 (the cartridge 7 is hidden simply for the
sake of clarity). As seen in FIG. 9(a), the fastener 6 is in the
relaxed or parent state. Referring now to FIGS. 10(a) and 10(b),
the cartridge retainer 16 is then advanced distally to partially
constrain the fastener 6 within the spreader 24 (shown in FIG.
10(a)).
[0062] With reference to FIGS. 11 (a) and 11(b), additional
depression of the lever 12 on the handle 10 advances the tongue 26
such that the teeth 26(a) drop into the loop portion 6(c) of the
fastener (shown best in FIG. 11(b)). The tongue 26 is fixedly
coupled to a trigger assembly 32 that may be translated distally as
the lever 12 on the handle is depressed. The trigger assembly 32 is
biased against an advancement mechanism 34 coupled to the actuating
lever 12. Actuation of the lever 12 causes the advancement
mechanism 34 to displace distally. This distal displacement is
translated to the trigger assembly 32 via a spring 36. The spring
36 is preferably stiff such that it acts as a rigid linkage between
the advancement mechanism 34 and trigger assembly 32 before the
compression stage (discussed in detail below). Translation of the
advancement mechanism 34 and trigger assembly 32 (and coupled
tongue 26) before the compression stage may be best seen in FIGS.
11(a), 11(b), 12(a), and 12(b).
[0063] Referring now to FIGS. 12(a) and 12(b), the fastener 6 is
then transformed into the fully constrained state (i.e., U-shaped
configuration) by advancing the tongue 26 distally, e.g., by
partially depressing the handle 10 of the tool 2. The teeth 26(a)
of the tongue 26 may advance between the tines 6(a), 6(b) of the
fastener 6 to direct the fastener 6 into the U-shaped
configuration. At this stage, the fastener 6 may still be retained
by retaining member 20.
[0064] FIGS. 13(a) and 13(b) illustrate the trigger assembly 32
abutting and pushing against a clamp 38 that is fixedly coupled to
the pusher member 30. Movement of the clamp 38 distally causes
corresponding distal movement of the pusher member 30 within the
tool 2. The pusher member 30 then advances distally such that the
cam 20(a) on the retaining member 20 exits the groove 30(a) in the
pusher member, thereby moving the retaining member 20 to the
disengaged position. Additional advancement of the handle 12 pushes
the fastener 6 down the ejection track 23 of the tool. During this
phase of deployment, both the tongue 26 and pusher member 30 move
distally in unison. Advancement of the fastener 6 may stop when the
tines 6(a), 6(b) project just beyond the distal-most end of the
tool 2 (as shown in FIGS. 13(a) and 13(b).
[0065] FIGS. 14(a) and 14(b) illustrate ejection of the fastener 6
from the tool 2. After the spring 36 has been fully compressed and
the actuating lever 12 is in the position shown in FIG. 15(e),
depression of the trigger 14 (illustrated by arrow D in FIG. 14(b))
causes the pusher member 30 to move rapidly in the distal direction
to eject the fastener 6 completely from the ejection track 23. As
best seen in FIG. 14(a), the fastener 6 may be ejected in the
U-shaped configuration into the adjacent tissue (not shown).
[0066] As seen in FIGS. 8 through 14, the tool 2 may also include a
proximally located restoring spring 40 to aid in restoring the
mechanical linkages (e.g., tongue 26, pusher member 30 and
associated trigger assembly 32 and advancement mechanism 34) after
the fastener 6 has been ejected from the tool 2.
[0067] FIGS. 15(a) through 15(e) illustrate the various stages of
an exemplary method that may be used to deliver a fastener 6 using
the fastener delivery tool 2. FIG. 15(a) illustrates a cartridge 7
carrying a fastener 6 being loaded into the loading chamber 18 of
the tool 2. FIG. 15(b) illustrates the cartridge retainer 16 being
moved distally (in the direction of the arrow in FIG. 15(b)). This
movement of the cartridge retainer 16 advances the spreader 24 (not
shown in FIG. 15) to place the fastener 6 in a partially
constrained state. FIG. 15(c) shows the handle 10 being depressed
partially. At this stage, the teeth 26(a) of the tongue 36 drops
into the loop portion of the fastener 6 and advances further
distally to transform the fastener 6 into the U-shaped
configuration. Additional movement of the handle 10 transfers the
fastener 6 from the loading chamber 18 to the ejection track 23 in
the distal tip 4 of the tool 2.
[0068] FIG. 15(d) illustrates the compression or load-driving step
whereby movement of the actuating lever 12 in the direction of the
arrow A shown in FIG. 15(d) causes compression of spring 36. FIG.
15(e) illustrates the tool 2 in the fully loaded state. The
fastener 6 is disposed at the distal tip 4 of the tool 2 with the
tines 6(a), 6(b) projecting distally from the ejection track 23.
The spring-loaded trigger 14 is then depressed to eject the
fastener 6 completely from the tool 2.
[0069] FIGS. 16(a) and 16(b) illustrate alternative configurations,
A, B, and C, for an elongated distal tip or snout 4 of the tool 2.
The tool 2 may include distal tips 4 of varying lengths in order to
facilitate the delivery process. For example, the tips 4 may have
lengths between about ten and four hundred millimeters (10-400 mm),
or between about five and fifty millimeters (5-50 mm).
[0070] The tips 4 may be integrally formed with the tool 2.
Alternatively, the tips 4 may be removable and/or interchangeable.
In this alternative, the tips 4 and/or tool 2 may include one or
more detents or other connectors (not shown) for removably
attaching an individual tip 4 to the tool 2. In addition, as best
seen in FIG. 16(b), the elongated distal tip or snout 4 may include
a variety of geometries or side-profiles, e.g., bends or curves, to
increase a user's field of view and/or otherwise facilitate
delivering a fastener. Thus, a tip 4 and/or tool 2 may be selected
given the particular anatomical presentations encountered during a
procedure.
[0071] Tip A shown in FIG. 16(b) illustrates a configuration in
which the elongated distal tip 4 has a straight or flat profile.
Tip B illustrates another configuration in which an intermediate
portion of the distal tip 4 is bent or curved out of the plane of
the tool 2. The bent or curved configuration is particularly
helpful in delivering the fastener 6 generally normal or
perpendicular to the surface of the surrounding tissue 90. Tip C
illustrates another configuration in which the distal tip 4 is
angled with respect to the longitudinal direction of the tool
2.
[0072] Turning to FIGS. 17(a)-17(c), tool 2 may be used to deliver
one or more fasteners 6, e.g., during a heart valve replacement
procedure. For example, the tool 2 may be used to deliver a
plurality of fasteners 6 through a sewing cuff or ring 51 of a
prosthetic heart valve 50 into surrounding tissue. Alternatively,
it will be appreciated that the tool 2 may be used to deliver one
or more fasteners 6, e.g., to secure other devices to tissue or to
another device, or to secure tissue structures together.
[0073] As shown, the prosthetic valve 50 is a multiple component
prosthesis, e.g., including a gasket member 52 (around which the
sewing cuff 51 may extend), and a valve member or "crown" (not
shown, e.g., including a frame and a plurality of leaflets, not
shown). Exemplary embodiments of single or multiple component
prosthetic heart valve assemblies that may be implanted using the
tool 2 are disclosed in U.S. Pat. No. 6,371,983 and in co-pending
applications Ser. Nos. 10/327,821, filed Dec. 20, 2002, and
10/765,725, filed Jan. 26, 2004. The entire disclosures of these
references are expressly incorporated by reference herein.
[0074] Initially, the gasket member 52 may be advanced into the
annulus 90, e.g., by a separate tool (not shown), and maintained at
a desired location, e.g., at a site from which native valve
leaflets have been removed. The distal tip 4 of the tool 2 (loaded
with a fastener 6) may be placed against the sewing cuff 51 with
the tip 4 substantially perpendicular to the sewing cuff 51. The
tool 2 may be actuated, e.g., by activating the lever 12 and/or
trigger 14, to deliver the fastener 6 through the sewing cuff 51
into the underlying tissue. Once the fastener 6 is ejected from the
distal tip 4, the tines of the fastener 6 may at least partially
recross within the tissue, thereby capturing a portion of the
sewing cuff 51 and the underlying tissue within the loop of the
fastener. A plurality of fasteners 6 may be successively delivered
about a circumference of the sewing cuff 51 to affix the prosthetic
valve 50 to the surrounding tissue 90.
[0075] FIG. 17(a) illustrates two exemplary fasteners 6 in the
fully deployed state. As shown in FIG. 17(a), after penetrating the
sewing cuff 51 and underlying tissue, the fasteners 6 may be biased
to revert towards the parent or unconstrained state (in which the
tines of the fasteners 6 at least partially overlap). In this
regard, the prosthetic valve 50 may be fixedly secured to the
surrounding tissue 90.
[0076] FIG. 17(c) illustrates an exemplary image from a radiography
device (not shown), illustrating a plurality of fasteners 6
deployed about the circumference of the prosthetic valve 50. The
fasteners 6 and a portion of the gasket member 52 are at least
partially radiopaque, and may be seen on a radiograph, while the
sewing cuff 51 (shown in phantom in FIG. 17(c)) may be
substantially radiolucent, and therefore not visible on the
radiograph.
[0077] Optionally, the fasteners 6 may be removable from tissue 90
and prosthetic valve 50, e.g., if it is desired to remove the valve
50 or relocate a particular fastener. For example, a pliers-like
tool (not shown) may be used to remove a fastener after ejection of
the fastener 6 from the tool 2, e.g., if the fastener 6 is oriented
incorrectly or the fastener 6 does not penetrate deeply enough into
the tissue 90. The physician grasp the loop portion 6(c) of the
fastener 6, which may remain at least partially exposed, using the
pliers-like tool. The fastener 6 may then be pulled or otherwise
retracted proximally to remove the tines of the fastener 6 from the
delivery site. A replacement fastener 6 may be loaded into the tool
2 and/or delivered to the delivery site, similar to the methods
described above.
[0078] In an alternative embodiment, a tool may be provided that
may accommodate loading multiple fasteners 6 into the tool 2
simultaneously or successively before delivery. Such a tool 2 may
be desirable because the tool 2 does not have to be removed from
the body cavity to load successive fasteners 6, which may
accelerate delivery of the fasteners 6. FIG. 18 illustrates an
embodiment of a tool 2, showing a plurality of fasteners 6 loaded
into a staging area or section 42. The fasteners 6 may be advanced
successively in the distal direction toward the distal tip 4 of the
tool 2. A cartridge (not shown) may be provided that holds a
plurality of fasteners 6 such that the tool 2 may be loaded with
multiple fasteners 6 simply by loading a single cartridge into the
tool 2.
[0079] 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.
* * * * *