U.S. patent application number 11/437842 was filed with the patent office on 2007-11-22 for pericardium management method for intra-pericardial surgical procedures.
This patent application is currently assigned to Acorn Cardiovascular, Inc.. Invention is credited to Aaron J. Hjelle, Richard C. Mattison, Paul Andrew Pignato, Robert G. Walsh.
Application Number | 20070270882 11/437842 |
Document ID | / |
Family ID | 38723885 |
Filed Date | 2007-11-22 |
United States Patent
Application |
20070270882 |
Kind Code |
A1 |
Hjelle; Aaron J. ; et
al. |
November 22, 2007 |
Pericardium management method for intra-pericardial surgical
procedures
Abstract
A method for managing the pericardium during intra-pericardial
procedures such as the delivery of cardiac support devices. One
embodiment of the method includes making an incision through the
pericardium to provide access to the pericardial space, and
inserting a plurality of strips of lubricious material into and
through the incision. The strips of material are spaced around the
edges of the incision to form a tubular barrier against the
pericardium. End portions of the strips of material in the
pericardial space are expanded away from the body to form a lip
that lines the inside of the pericardium around the incision.
Inventors: |
Hjelle; Aaron J.; (Champlin,
MN) ; Pignato; Paul Andrew; (Stacy, MN) ;
Walsh; Robert G.; (Lakeville, MN) ; Mattison; Richard
C.; (Zimmerman, MN) |
Correspondence
Address: |
FAEGRE & BENSON LLP;PATENT DOCKETING
2200 WELLS FARGO CENTER, 90 SOUTH SEVENTH STREET
MINNEAPOLIS
MN
55402-3901
US
|
Assignee: |
Acorn Cardiovascular, Inc.
St. Paul
MN
|
Family ID: |
38723885 |
Appl. No.: |
11/437842 |
Filed: |
May 19, 2006 |
Current U.S.
Class: |
606/108 ;
128/898 |
Current CPC
Class: |
A61B 2017/00849
20130101; A61B 17/0206 20130101; A61B 17/3439 20130101; A61B
17/3423 20130101; A61B 17/2833 20130101; A61B 17/02 20130101; A61B
2017/0237 20130101 |
Class at
Publication: |
606/108 ;
128/898 |
International
Class: |
A61B 17/02 20060101
A61B017/02; A61B 19/00 20060101 A61B019/00 |
Claims
1. A method for managing a patient's pericardium during an
intra-pericardial procedure, including: making an incision though
the pericardium to provide access to the pericardial space;
inserting one or more flexible members into and through the
incision; forming portions of the one or more flexible members into
a tubular barrier against exposed edges of the pericardium; and
extending portions of one or both ends of the one or more flexible
members away from the tubular barrier and around the exposed edges
of the pericardium to line at least portions of the pericardium
around incision.
2. The method of claim 1 wherein inserting one or more flexible
members includes inserting a tubular structure formed of flexible
material.
3. The method of claim 2 wherein extending end portions of the one
or more flexible members includes forming a lip on an end of the
tubular structure.
4. The method of claim 3 wherein forming the lip includes actuating
an actuating member to form the lip.
5. The method of claim 4 wherein actuating an actuating member
includes forming a hoop on the end portion of the tubular
structure.
6. The method of claim 3 wherein inserting one or more flexible
members into the incision includes inserting flexible sheet
material into the incision.
7. The method of claim 2 wherein extending end portions of the one
or more flexible members includes forming a lip on an end of the
tubular structure within the pericardial space and under the
pericardium.
8. The method of claim 1 wherein inserting one or more flexible
members includes inserting a plurality of flexible members.
9. The method of claim 8 wherein inserting a plurality of flexible
members includes inserting a plurality of strips of flexible
material.
10. The method of claim 9 wherein forming the tubular barrier
includes circumferentially spacing the strips of material around
the edges of the incision.
11. The method of claim 9 wherein extending end portions of the
flexible members includes fanning the end portions of the flexible
material away from the tubular barrier.
12. The method of claim 9 wherein inserting flexible material
includes inserting ends of strips of material extending from
circumferentially spaced locations around a hoop into the
incision.
13. The method of claim 9 wherein inserting the strips of flexible
material includes inserting the strips within the pericardial space
and extending ends of the strips under the pericardium.
14. The method of claim 9 wherein inserting flexible material
includes inserting material having a relatively low friction
surface.
15. The method of claim 9 wherein forming a portion of the one or
more flexible members into a tubular barrier includes attaching at
least portions of the strips of flexible material to one
another.
16. The method of claim 1 wherein inserting one or more flexible
members includes inserting relatively low friction members.
17. The method of claim 1 wherein extending portions of one or both
ends of the one or more flexible members includes increasing a
diameter of the portions of the members extending away from the
tubular barrier with respect to a diameter of the tubular
barrier.
18. The method of claim 1 wherein: inserting one or more flexible
members includes inserting a plurality of flexible members; and
forming portions of the flexible members into a tubular barrier
includes positioning edges of the flexible members adjacent to one
another.
19. The method of claim 18 wherein positioning edges of the
flexible members adjacent to one another includes overlapping the
edges of the flexible members.
20. The method of claim 18 and further including attaching portions
of the edges of adjacent flexible members.
Description
FIELD OF THE INVENTION
[0001] The invention is a method for manipulating the pericardium
during surgical or other procedures requiring access to the
pericardial space.
BACKGROUND OF THE INVENTION
[0002] The pericardium is a multi-layer membranous fibro serous sac
that surrounds the heart. An inner layer of the pericardium, known
as the serous pericardium, is adjacent to the outer layer of the
heart, also known as the epicardium. An outer layer of the
pericardium is known as the fibrous pericardium. Between the
fibrous pericardium and serous pericardium is a space known as the
pericardial space. The term "pericardium" is often used, however,
to refer only to the fibrous pericardium. Similarly, the term
"pericardial space" is often used to refer generally to the space
between the fibrous pericardium and the heart.
[0003] Certain surgical or other procedures on the heart require
access to the pericardial space through the pericardium. Known
approaches for accessing the pericardium and heart from outside the
body include sternotomy and sub-xyphoid approaches. One such
surgical procedure that requires access to the pericardial space is
the delivery of cardiac support devices. Cardiac support devices
are structures, sometimes referred to as jackets, that surround all
or portions of a diseased heart. These devices are intended to
treat chronic heart failure or other cardiac disease, which may be
associated valvular dysfunction, by constraining expansion of the
heart. They can be delivered and implanted using conventional
cardiothoracic surgical techniques or minimally invasive surgical
procedures. Devices of these types and associated delivery tools
and methods are shown, for example, in the following U.S. patents,
all of which are incorporated herein by reference in their
entirety.
TABLE-US-00001 Inventor Name Patent/Publication No. Alferness
5,702,343 Alferness et al. 6,123,662 Vanden Hoek et al. 6,293,906
Alferness et al. 6,482,146 Lau et al. 6,702,732 Walsh et al.
6,902,522 Girard et al. 6,951,534
[0004] Tools and methods for accessing the pericardial space and
for introducing other instruments and therapeutic devices such as
cardiac support devices into that space are also known. Examples of
tools and methods of these types are shown in the following U.S.
patents and published applications, all of which are incorporated
herein by reference in their entirety.
TABLE-US-00002 Inventor Name Patent/Publication No. Grabek
5,931,810 Schmidt 5,972,013 Schmidt et al. 6,206,004 Lau et al.
2005/0055032 Lau et al. 2005/0102010
[0005] Cardiac support devices of the type described above are
typically delivered through an incision in the pericardium near the
apex of the heart. Visualizing the heart and mounting the devices
through the incision can involve moving the incision and
manipulating the pericardium. In the course of these procedures the
pericardium can sometimes interfere with the delivery of the
device.
[0006] There is, therefore, a continuing need for improved devices
and methods for managing the pericardium during intra-pericardial
procedures. Devices and methods that can enhance cardiac support
device delivery procedures would be especially desirable.
SUMMARY OF THE INVENTION
[0007] The present invention is an improved method for managing a
patient's pericardium during intra-pericardial procedures. The
efficiency of procedures such as the delivery of cardiac support
devices can be greatly enhanced by the method.
[0008] One embodiment of the invention includes making an incision
though the pericardium to provide access to the pericardial space.
One or more flexible members are inserted into and through the
incision. Portions of the one or more flexible members are formed
into a tubular barrier against exposed edges of the pericardium.
Portions of one or both ends of the one or more flexible members
are formed away from the tubular barrier and around the exposed
edges of the pericardium to line at least portions of the
pericardium around the incision. The one or more flexible members
include a plurality of strips of flexible and lubricious material
in one embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1A is an isometric view of a pericardium management
tool in accordance with one embodiment of the present invention in
a retracted state.
[0010] FIG. 1B is an isometric view of the pericardium management
tool shown in FIG. 1A in an expanded state.
[0011] FIGS. 2A-2C are illustrations of the pericardium management
tool shown in FIG. 1A being inserted into and deployed within a
patient's pericardial space.
[0012] FIG. 3 is an isometric view of a device for inserting and
deploying the pericardium management tool shown in FIG. 1A.
[0013] FIG. 4 is a top view of the deployment device shown in FIG.
3.
[0014] FIG. 5 is an isometric view, taken from the side, showing
the pericardium management tool of FIG. 1A on the deployment device
of FIG. 3, with the internal end of the tool and device inserted
into and deployed with the pericardial space.
[0015] FIG. 6 is an isometric view of the deployed tool and device
shown in FIG. 5.
[0016] FIG. 7 is an isometric view of a pericardium management tool
in accordance with another embodiment of the invention.
[0017] FIGS. 8A-8C are illustrations of the pericardium management
tool shown in FIG. 7 being inserted into and deployed within a
patient's pericardial space.
[0018] FIG. 9 is a top view of the deployed pericardium management
tool shown in FIG. 7.
[0019] FIGS. 10A and 10B are top views of a pericardium retractor
in accordance with another embodiment of the invention in closed
and open states, respectively.
[0020] FIGS. 11A and 11B are detailed isometric views of the blades
of the retractor shown in FIGS. 10A and 10B in the closed and open
states, respectively.
[0021] FIGS. 12A and 12B are illustrations of the retractor shown
in FIGS. 10A and 10B being inserted into and opened within a
patient's pericardial space.
[0022] FIG. 13 is a top view of a pericardium retractor in
accordance with another embodiment of the invention inserted into
and opened within a pericardial space.
[0023] FIG. 14 is a side view of the retractor shown in FIG. 13
within the pericardial space.
[0024] FIG. 15 is a side view of a pericardium management tool in
accordance with another embodiment of the invention deployed within
an incision through a patient's pericardium.
[0025] FIG. 16 is an illustration of a plurality of flexible
members that can be assembled to form the tool shown in FIG.
15.
[0026] FIG. 17 is a sectional view of an alternative version of one
of the flexible members shown in FIG. 16.
[0027] FIG. 18 is a sectional view of another alternative version
of one of the flexible members shown in FIG. 16.
[0028] FIG. 19 is a side view of yet another alternative version of
one of the flexible members shown in FIG. 16.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] FIGS. 1A and 1B are illustrations of a pericardium
management tool 10 in accordance with one embodiment of the
invention. As shown, the tool 10 is a flexible member having a
tubular body 12 with a first or external end 14 and a second or
internal end 16. A barrier portion 18 of the body 12 between the
ends 14 and 16 has a diameter D.sub.BP. A lip 20 on the external
end 14 of the body 12 has a diameter D.sub.EL that is greater than
the diameter D.sub.BP of the barrier portion 18. An extendable lip
22 on the internal end 16 of the body 12 is expandable with respect
to the body between a first or retracted state shown in FIG. 1A and
a second or expanded state shown in FIG. 1B. In the retracted state
shown in FIG. 1A, the extendable lip 22 has a diameter D.sub.IL1
that can be greater than, less than or equal to the diameter
D.sub.BP of the barrier portion 18. In the embodiment shown, the
extendable lip structure 22 has a diameter D.sub.IL1 in its
retracted state that is slightly larger than the diameter D.sub.BP
of the barrier portion 18. In the expanded state shown in FIG. 1B,
the extendable lip structure 22 has a diameter D.sub.IL2 that is
greater than the diameter D.sub.BP of the barrier portion 18.
[0030] In the embodiment shown in FIGS. 1A and 1B, the entire body
12 is formed from flexible (i.e., compliant) material such as
fabric manufactured of expanded PTFE threads. Material of this type
is commercially available as Gore-Tex fabric from W.L. Gore. Some
embodiments of the invention are formed from material that is also
expandable, although other embodiments of the invention are
constructed from material that is not expandable. Materials of this
type can also be elastic, although other embodiments of the
invention are constructed from material that is not elastic.
Another characteristic of material of this type is that it has a
relatively low coefficient of friction, and therefore has
relatively low friction surfaces. Still other embodiments of the
invention are formed from other materials (e.g., Dacron) having a
lubricious coating.
[0031] In the embodiment of pericardium management tool 10 shown in
FIGS. 1A and 1B, the lip 20 on the external end 14 of body 12 is
fixed in size. The lip 20 can, for example, be formed by stretching
the fabric around a hoop (not visible) of wire or other elongated
material to form a tubular pocket 23, and forming a hem in the
fabric to retain the hoop inside the tubular pocket. As shown in
FIGS. 1A and 1B, in this embodiment of the tool 10, the diameter of
the body 12 continuously increases between the diameter D.sub.BP of
the barrier portion 18 and the diameter D.sub.EL of the external
lip 20.
[0032] The extendable lip 22 is moved between its retracted and
expanded states in this embodiment by a flexible elongated element
such as wire 24 that is inserted into and withdrawn from a tubular
pocket 26 in the internal end 16 of the body 12. Pocket 26 can be
formed by folding and hemming the fabric on the end 16 of the body
12. By forcing the wire 24 in a direction generally parallel to its
length into the pocket 26 through a hole (not shown), the wire is
be formed into a hoop of increasing circumference and diameter that
stretches the fabric of the body 12 to expand the lip 22. The lip
22 is retracted by withdrawing the wire 24 from the pocket 26.
[0033] FIGS. 2A-2C illustrate a method for operating and deploying
the tool 10 to manage a patient's pericardium 30 and provide access
to heart 32. The pericardium 30 is accessed from a desired location
through the patient's skin 31. An incision 34 is then made through
the pericardium 30 to provide access to the pericardial space 36
surrounding heart 32. As shown in FIG. 2A, the internal end 16 of
the body 12 is inserted through the skin 31 and incision 34, and
positioned within the pericardial space 36. The lip 20 on the
external end 14 of the body 12 will remain on the outside of the
pericardium 30, and typically on the outside of the patient's skin
31.
[0034] The expansion of lip 22 can then be initiated by forcing the
wire 24 into the pocket 26 as shown in FIG. 2B. As the wire 24 is
fed into the pocket 26 the circumference and diameter of the lip 22
will expand with respect to the barrier portion 18 and draw the
internal end 16 of the body 12 closer to the interior surface of
pericardium 30. This expansion operation continues until the lip 22
is in its expanded state shown in FIG. 2C. When the tool 10 is
deployed with the lip 22 in the expanded state, the barrier portion
18 of the body 12 forms a tubular structure around and against the
exposed edges of the pericardium 30 and skin 31. The lip 22 also
extends beyond the edges of the incision 34 and forces the fabric
of the lip and body 12 to be positioned on or adjacent to the
interior surfaces of the pericardium 30 around the incision. The
lip 22 thereby covers or lines the inside surface of the
pericardium 30 around the incision 34. Similarly, this deployment
causes the external lip 20 to be located on or least adjacent to
the external surface of the patient's skin 31, with the fabric of
the external lip and body 12 extending beyond and around the
opening over the external surface of the skin to form a cover or
lining.
[0035] Tool 10 can be efficiently inserted and deployed. The
deployed tool 10 surrounds the incision 34 in the pericardium 30
and provides a low-friction access port to the pericardial space
36. Since the edges of the pericardium 30 at the incision 34 are
covered and protected, they will not interfere with surgical or
other procedures being performed through the deployed tool 10. The
deployed tool 10 also engages the pericardium 30 around the
incision 34 to such a degree that the tool can be manipulated to
lift, shift or otherwise move the location of the barrier portion
18, and therefore the access port, as desired during the surgical
procedure. The surgeon can thereby effectively enhance his or her
visualization of and access to the pericardial space 36 without
interference from the edges of the pericardium 30. The
characteristics of the tool 10 also enable the device to
continually resize and conform to changes in the shape or size of
the incision 34 that might be caused during the surgical
procedure.
[0036] Upon completion of the surgical or other procedure the tool
10 can be removed from the incision 34. This removal can be
facilitated by returning the lip 22 on the internal end 16 to its
retracted state (e.g., by withdrawing the wire 24). The above
described advantages of the tool 10 are thereby achieved by a
device that can be efficiently removed following the completion of
the procedure.
[0037] Pericardial management tools in accordance with the
invention and having features and advantages such as those
described above in connection with tool 10 can take other forms. By
way of example, and not shown, in other embodiments of the
invention the barrier portion 18 and lip 20 on external end 14 can
be formed of rigid materials such as polymers. The lip 20 on the
external end 14 need not be fixed, but instead can have structures
such as those of the lip 22 on the internal end 16 that can be
moved between retracted and expanded states. The extendable lip 22
can also be formed from different materials, including rigid
materials, and different structures and methods can be used to move
the lip between its retracted and expanded states. In still other
embodiments, the tool includes a low friction material coating
(e.g., in solid or liquid form) on the interior surfaces of the
body 12 or at least on the barrier portion 18. The entire tool 10,
or just portions, can be constructed from any suitable material
such as, for example, fabrics, metals, polymers or biologic
materials. The exterior surface of the tool 10 near the lips 20
and/or 22 can also include adhesive elements or coatings, or other
tissue-engaging structures or material, that will facilitate the
attachment of the lips to the adjacent tissue when the device is
deployed. Although the tubular body 12 has a circular cross section
in the illustrated embodiment, other embodiments (not shown) have
other cross sectional shapes.
[0038] FIGS. 3 and 4 are illustrations of a deployment device 50
that can be used to insert and deploy the pericardium management
tool 10. As shown, deployment device 50 has a handle 52 with a pair
of guide members 54 extending from one end. The guide members 54
are tubes and have fingers 56 on the ends opposite the handle 52
that extend in a direction back toward and generally parallel to
the handle. The wire 24 that is used to deploy the tool 10 (not
shown in FIGS. 3 or 4) extends through the guide members 54 and out
the ends of the fingers 56. The portion of the wire 24 extending
from the fingers 56 forms a hoop that is located in the extendable
lip 22 of the tool 10 when the tool is mounted on the deployment
device 50, thereby supporting the tool during its use. The ends of
the wire 24 extending from the ends of the guide members 54 mounted
to the handle 52 are connected to a slide 60. Slide 60 is movably
mounted to the handle 52, and in the embodiment shown is mounted to
a slot 62 for movement along the length of the handle. The
circumference and diameter of the hoop in the wire 24 can be
expanded and retracted by moving the slide 60 toward and away from
the end of the handle 52 with the guide members 54,
respectively.
[0039] FIGS. 5 and 6 are illustrations of the pericardium
management tool 10 mounted to the deployment device 50. A cover 64
of flexible fabric encloses the portions of the deployment device
50 between the slide 60 and end portion of handle 52. The internal
end 16 and extendable lip 22 of the tool 10 (not visible in FIGS. 5
and 6) are positioned through an incision 34 into mammalian
pericardium 30 in these figures. The slide 60 has been actuated
(e.g., by the surgeon's thumb) to drive the extendable lip 22 to
its expanded state. In FIG. 6 the pericardial space 36 and heart 32
are visible through the opening in the body 12.
[0040] FIG. 7 is an illustration of a pericardium management tool
110 in accordance with another embodiment of the invention. As
shown, tool 110 includes a hoop 170 and a body 112 formed by a
plurality of flexible members such as material strips 172. The
material strips 172 can be formed of any of the materials of the
body 12 of tool 10 described above. In one embodiment, for example,
strips 172 are formed of relatively low friction and flexible
material such as PTFE. The strips 172 extend from the hoop at
spaced apart locations and can be formed of relatively thin sheet
material. Hoop 170 can be an elongated metal or polymer member
(e.g., wire). Material strips 172 can be attached to the hoop 170
by wrapping the ends of the strips around the hoop and securing the
ends to the hoop or adjacent portions of the strips (e.g., by a
sewn hem or adhesive). The end 114 of tool 110 at which the
material strips 172 are attached to the hoop 170 is an exterior end
of the tool, while the free ends of the strips are at an internal
end 116 of the tool.
[0041] FIGS. 8A-8C and 9 illustrate a method for operating and
deploying the tool 110 to manage a patient's pericardium 130 and
provide access to heart 132. The pericardium 130 is accessed from a
desired location through the patient's skin 131. An incision 134 is
then made through the pericardium 130 to provide access to the
pericardial space 136 surrounding heart 132. As shown in FIG. 8A,
the portions of material strips 172 on the internal end 116 of the
body 112 are inserted through the skin 131 and incision 134, and
positioned within the pericardial space 136. The body 112 of the
device 10 is in a retracted state during this insertion step. The
hoop 170 on the external end 114 of the body 112 functions as a lip
120 and remains on the outside of the pericardium 130, and
typically on the outside of the patient's skin 131.
[0042] The body 112 of tool 110 is then expanded within the
pericardial space 136 by radially extending the free ends of the
material strips 172 in a fanned arrangement under the pericardium
130. The portions of the material strips 172 on the internal end
116 of the body 112 are thereby expanded in diameter and
circumference with respect to the diameter and circumference of a
barrier portion 118 that engages the edges of the pericardium 130
at the incision 134. These steps can be done by hand (e.g., by the
surgeon using his or her fingers to tuck the material strips 172
under the pericardium 130) or with the assistance of instruments.
The portions of the material strips 172 on the ends 116 of the body
112 form a lip 122 under the pericardium 130. This expansion
operation continues until the lip 122 is in its expanded state
shown in FIG. 8C.
[0043] As perhaps best shown in FIGS. 8C and 9, when the tool 110
is deployed with the lip 122 in the expanded state, the portions of
the material strips 172 at barrier portion 118 are positioned
closely adjacent to one another and form a tubular structure
against the exposed edges of the pericardium 130 and skin 131. In
the illustrated embodiment the portions of the material strips 172
at barrier portion 118 are located immediately adjacent to one
another. In other embodiments (not shown) the strips 172 can
overlap one another, or be spaced from one other, at barrier
portion 118.
[0044] The lip 122 extends beyond and around the edges of the
incision 134 and forces the material strips 172 to be positioned on
or adjacent to the interior surfaces of the pericardium 130 around
the incision, thereby lining the pericardium around the incision.
When deployed, the illustrated embodiment of tool 110 has gaps in
the lip 122 between the material strips 172. However substantial
portions of the pericardium 130 around the incision 134 are still
lined by the lip 122 (e.g., sufficient portions to reduce or
prevent the pericardium from interfering with the surgical
procedure). Following this deployment operation the external lip
120 will typically be located on or at least adjacent to the
external surface of the patient's skin 131, with the material of
strips 172 at the lip 120 and body 112 extending beyond and around
the opening over the external surface of the skin.
[0045] Pericardium management tool 110 can be efficiently inserted
and deployed to surround the incision and provide a low-friction
access port to the pericardial space 136. FIG. 9, for example,
shows how the deployed tool 110 provides access to the pericardial
space 136 and heart 132. The tool 110 can be removed from the
incision 134 following the completion of the surgical procedure by
returning the lip 122 to its retracted state and pulling the body
112 out of the incision. The functions and associated advantages
provided by pericardium management tool 110 are the same or similar
to those of tool 10 described above.
[0046] Pericardium management tools in accordance with the
invention having features and advantages such as those described
above in connection with tool 110 can take other forms. By way of
example, and not shown, in other embodiments if the invention the
portions of the strips 172 (e.g., flexible members) that are
positioned on the outside and/or the inside of the pericardium 130
can be formed of rigid material, and the portions of the strips
forming the barrier portion 118 can be formed of flexible material
or have hinge structures that enable the ends to be fanned out
within the pericardial space 136. Malleable metals or other
material or structures can be added to the material strips 172 at
the barrier portion 118 to cause the strips to retain their
expanded state positions. The strips need not be formed of low
friction material, but can instead be formed of other materials and
have a coating of low friction material on at least those portions
forming the interior surface of barrier portion 118. The material
strips 172 can also be curved or otherwise shaped to reduce or
eliminate the size of the gaps between the strips at the lips 120
and/or 122 when the tool 110 is deployed. Adhesive or other
structures (e.g., hook and loop fasteners) on the material strips
(e.g., on the edges) can be used to secure the strips to one
another. Other features of the tool 10 described above can also be
incorporated into tool 110.
[0047] A retractor 200 in accordance with another embodiment of the
invention is shown in FIGS. 10A and 10B. Retractor 200 includes a
handle 202, a pair of blades 204 and an actuating member 208.
Blades 204 are shown in greater detail in FIGS. 11A and 11B. The
retractor 200 and blades 204 are shown in a closed or retracted
position in FIGS. 10A and 11A with the blades located adjacent to
one another, and in an open or extended position in FIGS. 10B and
11B with the blades spaced apart from one another.
[0048] Blades 204 each have an upright wall portion 210 and a lip
212 extending from the wall portion. Wall portions 210 have a
convex surface in the embodiment shown. Similarly, in the
embodiment shown the lips 212 have a convex outer edge. In other
embodiments of the invention the wall portions 210 and the outer
edges of the lips 212 have other shapes (e.g., are flat or
straight).
[0049] Handle 202 is an elongated member in the embodiment shown
and has a proximal end 214 and a distal end 216. One of the blades
204 (i.e., a fixed blade) is mounted to the distal end 216 of the
handle 202 with the lip 212 facing the proximal end 214. An
elongated member such as shaft 215 can mount the fixed blade 204 to
the handle 202. Actuating member 208 includes a U-shaped arm 217
with a proximal end 218 movably mounted to the handle 202 and a
distal end 220 mounted to the other blade 204 (i.e., the movable
blade). The blade 204 is mounted to the distal end 220 of arm 217
with the lip 212 of the blade facing away from the distal end 216
of the handle 202. In the embodiment shown, the proximal end 218 of
arm 217 is slidably mounted to a slot 222 in the handle 202 by an a
slide 224.
[0050] The operation of retractor 200 can be described with
reference to FIGS. 10A, 10B, 11A, 11B, 12A and 12B. The pericardium
230 is accessed from a desired location through the patient's skin
231. An incision 234 is then made through the pericardium 230 to
provide access to the pericardial space 236. With the handle 202
and actuating member 208 manipulated so the blades 204 are in the
closed position shown in FIGS. 10A and 11A, the blades are inserted
through the incision 234 to position the lips 212 within the
pericardial space 236 as shown in FIG. 12A. The actuating member
208 is then actuated to move the blades 204 to the open position
shown in FIGS. 10B and 11B. This expansion of the blades 204 will
cause the wall portions 210 of the blades to engage the exposed
edges of the pericardium 230, and the lips 212 to extend beyond the
edges of the incision over the inside surface of the pericardium
230. The incision 234 is thereby spread apart, and the edges of the
pericardium 230 at the incision engaged, to provide access to the
pericardial space 236 and heart 232. A releasable clamp mechanism
(not shown) on the handle can be used to retain the retractor 200
in the open position during surgical procedures. Upon completion of
the surgical procedure the retractor 200 can be returned to its
closed position and withdrawn from the incision 234.
[0051] Retractor 200 can be efficiently operated. The retractor 200
provides functions and advantages that are the same or similar to
those described above in connection with tool 10. Retractor 200 can
be used alone to access the pericardial space 236. Alternatively,
tools such as 10 and 110 described above can be used in connection
with the retractor 200 by inserting them into the opening created
by the retractor.
[0052] FIGS. 13 and 14 are illustrations of a retractor 300 in
accordance with another embodiment of the invention. In these
figures the retractor 300 is shown in an open state with the blades
304 within the pericardium 330 of a mammal, exposing the
pericardial space 336 and heart 332. In the embodiment shown, the
actuating mechanism and handle of retractor 300 formed by a
hand-held clamp mechanism 303 having a pair of arms 305 pivotally
connected by a hinge 307. A releasable locking mechanism 311 is
connected to the hand-engaging sections 313 of the arms 305. The
blades 304 are mounted directly to the arms 305. The edges of the
lips 312 are generally linear, and the wall portions 310 are
generally planar. Other than these differences, retractor 300 can
be substantially the same or similar to retractor 200 described
above, and functions in manner that is substantially the same or
similar to that of retractor 200.
[0053] FIG. 15 is an illustration of a pericardium management tool
410 in accordance with another embodiment of the invention. Tool
410 is formed from a plurality of individual material strips 472
such as those shown in FIG. 16. Material strips 472 can be formed
from any of the materials and/or structures of material strips 172
of tool 110 described above (e.g., low friction and flexible
materials), and have an external end 414 and an internal end 416.
In the embodiment shown, the material strips 472 are elongated
members having concave side edges 475. Adhesive 473 is located on
at least one side of the material strips 472 adjacent to at least
one of the edges.
[0054] Tool 410 is deployed by inserting the material strips 472
individually into an incision 434 in the pericardium 430. Internal
ends 416 are then tucked under the internal surface of the
pericardium 430, and the external ends 414 are bent over the
outside of the pericardium 430 or body. Adjacent side edges 475 of
the material strips 472 can be joined together. In the embodiment
shown in FIGS. 15 and 16, for example, the side edges 475 are
overlapped and secured together by the adhesive 473. When deployed,
the tool 410 has a tubular body 412 with a barrier portion 418 that
engages and surrounds the edge of the pericardium 430 at the
incision 434. The internal ends 416 of the material strips 472 are
extended from retracted positions to form an extendable lip 422
that lines the interior surface of the pericardium 430 around the
incision 434. The external ends 414 form a lip 420 on the outside
surface of the pericardium 430 or body.
[0055] Pericardium management tool 410 can be efficiently inserted
and deployed to surround the incision 434 and provide a
low-friction access port to the pericardial space 436. The tool 410
can be removed from the incision 434 following the completion of
the intra-pericardial procedure by pulling the body 412 out of the
incision. The functions and advantages provided by pericardial
management tool 410 are the same or similar to those of tools 10
and 110 described above.
[0056] Pericardium management tools in accordance with the
invention having features and advantages such as those described
above in connection with tool 410 can take other forms. By way of
example, FIG. 17 illustrates a cross section of a material strip
472' having an arcuate cross section. The actuate cross section of
material strip 472' provides the strip with beam strength, and
enhances the its ability to be deployed as part of the tool. FIG.
18 illustrates the external end 414'' of a material strip 472''. As
shown, the end 414 includes an engagement structure such as pocket
481'' that can be engaged by an instrument or other tool during the
deployment of the tool. FIG. 19 illustrates a material strip 472'''
having a tissue-engaging structure such as adhesive strip 485''' on
its external end 414''' and a malleable material strip 483'''
adjacent the barrier portion 418'''. Adhesive strip 485''' can be
used to enhance the engagement of the end 414''' with the
pericardium (not shown) when deployed as part of the tool in the
manner described above. Malleable material strip 483''' can help
the material strip 472''' retain its shape when deployed as part of
the tool, yet allow the material strip to be returned to other
shapes during the removal of the tool. Of course the features of
the material strips shown in FIGS. 17-19 can be combined with one
another and with the features of the material strips 472 described
above. Similarly, features of the tools 10 and 110 described above
can be incorporated into material strips 472 and tool 410. Other
structures such as snaps, magnets or hook and loop fasteners can be
used as alternatives to the adhesive 473 to secure the material
strips 472 to one another. The material strips 472 can have side
edges with straight or other shape profiles, and need not be
configured to engage adjacent material strips along their entire
lengths. A plurality of the material strips 472 can be distributed
together as a kit for assembling the tool. For example, in one
embodiment (not shown) a plurality of the material strips 472 are
packaged together as a kit for this purpose.
[0057] Although the present invention has been described with
reference to preferred embodiments, those skilled in the art will
recognize that changes can be made in form and detail without
departing from the spirit and scope of the invention. For example,
although not shown, tools and methods in accordance with the
invention can be incorporated into delivery tools for cardiac
support devices.
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