U.S. patent application number 17/651409 was filed with the patent office on 2022-06-02 for heart anchor device.
This patent application is currently assigned to V-Wave Ltd.. The applicant listed for this patent is V-Wave Ltd.. Invention is credited to Ori BEN-AMOTZ, Eyal BENBENISTI, Itshak COHEN, Tamar HAREL, Doron KOPELMAN, Tamir LEVI, Meir ROSENBERG, Yoram ROZY, Roey SHAFRIR.
Application Number | 20220168098 17/651409 |
Document ID | / |
Family ID | |
Filed Date | 2022-06-02 |
United States Patent
Application |
20220168098 |
Kind Code |
A1 |
LEVI; Tamir ; et
al. |
June 2, 2022 |
HEART ANCHOR DEVICE
Abstract
A medical implant including an anchor portion including a
plurality of arms adapted to engage an internal tissue wall of a
body from two opposite faces, wherein the anchor portion is
configured such that at least one of the arms does not have an
entirely overlapping arm on the other side of the wall and an
opening portion adapted to define an opening for blood flow through
the internal tissue wall, when the anchor portion engages the
wall.
Inventors: |
LEVI; Tamir; (Moshav
Ein-HaEmek, IL) ; ROSENBERG; Meir; (Newton, MA)
; BEN-AMOTZ; Ori; (Caesarea, IL) ; ROZY;
Yoram; (Caesarea, IL) ; BENBENISTI; Eyal;
(Hod-HaSharon, IL) ; SHAFRIR; Roey; (Modiin,
IL) ; KOPELMAN; Doron; (Caesarea, IL) ; COHEN;
Itshak; (Ramat-HaSharon, IL) ; HAREL; Tamar;
(Haifa, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
V-Wave Ltd. |
Caesarea |
|
IL |
|
|
Assignee: |
V-Wave Ltd.
Caesarea
IL
|
Appl. No.: |
17/651409 |
Filed: |
February 16, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16505624 |
Jul 8, 2019 |
11253353 |
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17651409 |
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15624314 |
Jun 15, 2017 |
10357357 |
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16505624 |
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12223080 |
Jul 16, 2014 |
9681948 |
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PCT/IB2007/050234 |
Jan 23, 2007 |
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15624314 |
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60862496 |
Oct 23, 2006 |
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60777315 |
Feb 28, 2006 |
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60761192 |
Jan 23, 2006 |
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International
Class: |
A61F 2/24 20060101
A61F002/24; A61B 17/00 20060101 A61B017/00 |
Claims
1. A shunt for implantation at an atrial septum within a heart, the
shunt comprising: an anchor portion configured to transition from a
collapsed state to a deployed state, the anchor portion comprising
a first plurality of petals configured to engage, in the deployed
state, a face of the atrial septum and a second plurality of petals
configured to engage, in the deployed state, an opposing face of
the atrial septum, wherein the anchor portion is configured such
that at least one of the petals of the first plurality does not
have an entirely overlapping petal in the second plurality on the
opposing face of the atrial septum; and an opening portion adapted
to define an opening for blood flow through the atrial septum in
the deployed state when the anchor portion engages the atrial
septum.
2. The shunt of claim 1, wherein the anchor portion does not
penetrate the atrial septum.
3. The shunt of claim 1, wherein the opening portion is configured
to radially expand during the transition from the collapsed state
to the deployed state.
4. The shunt of claim 1, wherein the anchor portion and the opening
portion are formed from a tube.
5. The shunt of claim 4, wherein the anchor portion and the opening
portion are formed by laser cutting out of the tube.
6. The shunt of claim 1, wherein the shunt is configured to permit
blood flow through the atrial septum via the opening from a left
atrium to a right atrium in an amount sufficient to alleviate high
pressures associated with heart failure.
7. The shunt of claim 1, wherein the shunt further comprises
radio-opaque markers.
8. The shunt of claim 1, wherein the opening has a diameter in the
deployed state of at least 6 millimeters.
9. The shunt of claim 1, wherein the anchor portion and the opening
portion are formed from a metal frame.
10. The shunt of claim 1, wherein the anchor portion and the
opening portion are formed from a single piece of nitinol.
11. The shunt of claim 1, wherein the first plurality of petals are
configured to transition from the collapsed state to the deployed
state when deployed in a first atrium and, after deployment of the
first plurality of petals, the second plurality of petals are
configured to transition from the collapsed state to the deployed
state when deployed in a second atrium, to thereby implant the
shunt at the atrial septum.
12. The shunt of claim 1, wherein each petal of the first plurality
of petals has a triangular shape.
13. The shunt of claim 12, wherein each petal of the first
plurality of petals is configured to lie flat on the face of the
atrial septum.
14. The shun ach petal of the second plurality of petals has a
triangular shape.
15. The shunt of claim 1, wherein each petal of the second
plurality of petals is configured to curve towards the atrial
septum such that a distal portion of each petal applies pressure to
the opposing face of the atrial septum.
16. The shunt of claim 1, wherein the first and second pluralities
of petals are formed of a super-elastic material.
17. The shunt of claim 1, wherein, in the deployed state, at least
one of the petals of the first plurality of petals does not have a
partially overlapping petal from the second plurality of
petals.
18. The shunt of claim 1, wherein the first and second pluralities
of petals are configured to surround the opening in the deployed
state.
19. The shunt of claim 1, wherein none of the petals of the first
plurality of petals fully overlaps with a petal in the second
plurality of petals in the deployed state.
20. The shunt of claim 1, wherein the shunt is configured such that
the opening remains clear from elements mounted therein.
21. The shunt of claim 1, further comprising a valve mounted on the
anchor portion in a manner which regulates blood flow through the
opening defined by the opening portion.
22. The shunt of claim 1, further comprising a sensor mounted on
the anchor portion.
23. The shunt of claim 1, wherein portions of the shunt are covered
by ePTFE or polyurethane.
24. The shunt of claim 1, wherein the first and second pluralities
of petals are arranged alternately around the opening, such that
each petal of the first plurality of petals is neighbored by a
petal of the second plurality of petals on one side and another
petal of the second plurality of petal on the opposite side.
25. A method for delivering the shunt of claim 1, the method
comprising: creating an orifice in the atrial septum of the body
via a transeptal puncture tool; and deploying the shunt within the
orifice such that the anchor portion engages the atrial septum and
the opening portion defines the opening for blood flow through the
orifice of the atrial septum.
26. The method of claim 25, wherein the transeptal puncture tool
comprises a, needle and a dilator catheter.
27. The method of claim 25, wherein deploying the shunt within the
orifice comprises percutaneously deploying the shunt such that the
opening portion self-expands within the orifice and further expands
the orifice.
28. The method of claim 27, wherein deploying the shunt comprises
percutaneously deploying the shunt such that the first plurality of
petals self-expands within a left atrium and, after the first
plurality of petals self-expands, the second plurality of petals
self-expands within a right atrium.
29. A shunt for implantation at an atrial septum within a heart,
the shunt comprising: a nitinol body comprising a first plurality
of petals configured to engage, in a deployed state, a face of the
atrial septum and a second plurality of petals configured to
engage, in the deployed state, an opposing face of the atrial
septum, wherein the nitinol body is configured such each petal of
the first plurality of petals does not have an entirely overlapping
petal in the second plurality of petals on the opposing face of the
atrial septum, wherein the nitinol body defines an opening for
blood flow through the atrial septum in the deployed state when the
nitinol body engages the atrial septum.
30. The shunt of claim 29, wherein the first and second pluralities
of petals are arranged alternately around the opening, such that
each petal of the first plurality of petals is neighbored by a
petal of the second plurality of petals on one side and another
petal of the second plurality of petal on the opposite side.
Description
RELATED APPLICATIONS
[0001] The present application claims the benefit under 35 USC
119(e) of U.S. Provisional applications 60/862,496, filed Oct. 23,
2006, 60/777,315, filed Feb. 28, 2006 and 60/761,192, filed Jan.
23,2006, the disclosures of all of which are incorporated herein by
reference in their entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to heart implants for example
to implants for the heart which can be delivered in a minimally
invasive procedure.
BACKGROUND OF THE INVENTION
[0003] The heart operates as a pump which causes blood to flow
throughout the body. In various cases, patients suffer from
blockages and/or pressure elevation and it is required to keep a
passage open for blood flow. In other patients, an undesired flow
path opens and it is required to close the flow path. In such
patients, stents, valves or seals are implanted to achieve a
required blood flow pattern.
[0004] An article titled "Creation with a stent of an unrestrictive
lasting atrial communication", by Marc Gewillig et a., Cardiol
Young 2002; 12(4):404-7, the disclosure of which is incorporated
herein by reference, describes use of a stent to create an
unrestrictive and atrial communication. An article titled "Modified
technique of stent fenestration of the atrial septum", Stumper et
al., 89 (10): 1227, Heart 2003, the disclosure of which is
incorporated herein by reference, describes placing a stent across
a fenestration and expanding the stent by a balloon.
[0005] Various closure devices are known in the art.
[0006] PCT publication WO 2005/027752, filed Sep. 13, 2004, the
disclosure of which is incorporated herein by reference, describes
a closure device formed of a pair of anchor members and a center
flexible joint, which press on the septum and hold it closed.
[0007] US patent publication 2006/0122647 to Callaghan et al.,
published Jun. 8, 2006, describes an occlusion device formed of a
polymer tube that includes distal and proximal ends for securing to
opposite ends of the septum.
[0008] US patent publication 2007/0010852, to Blaeser et al.,
published Jan. 11, 2007, the disclosure of which is incorporated
herein by reference, describes a device for sealing a patent
foramen ovale (PFO) in the heart. The device includes a right
atrial member including a plurality of arms and a cover attached to
the arms, and a left atrial anchor including a plurality of
arms.
[0009] There are also various valves known in the art.
[0010] PCT publication WO 2005/074367, published Aug. 18, 2005, the
disclosure of which is incorporated herein by reference, describes
a plurality of valves and methods of anchoring the valves in the
heart. One anchoring method described is use of support arms
opposite each other on both sides of a wall through which the valve
passes.
[0011] US patent publication 2006/0167541 to Lattouf, published
Jul. 27, 2006, disclosure of which is incorporated herein by
reference, describes a valve formed of a tube with hooks on both
ends for anchoring in the heart and a leaflet valve placed in the
tube.
[0012] US patent publication 2004/0162514 to Alferness, the
disclosure of which is incorporated herein by reference, describes
a pop-off valve for placement in the heart between the left and
right atriums. The valve includes spikes, referred to as anchor
guides, which pierce a wall of the heart and thus keep the device
in place. Such piercing is not always desirable as it may damage
heart tissue.
[0013] US patent publication 2006/0116710 to Corcoran et ale, the
disclosure of which is incorporated herein by reference, describes
an occlusion device having a relatively low profile against the
occluded tissue.
SUMMARY OF THE INVENTION
[0014] An aspect of some embodiments of the present invention
relates to a medical implant adapted to define a passage in a
tissue wall and to be anchored to the wall by a plurality of arms
on both sides of the wall, at least some of the arms not having a
matching overlapping arm on the other side of the wall.
[0015] The arms optionally extend radially from the defined
passage.
[0016] In some embodiments of the invention, at least some of the
arms do not have a corresponding arm on the other side of the wall,
even not a corresponding arm which only partially matches the area
of the arm. Alternatively or additionally, one or more of the arms
have a corresponding arm on the other side of the wall whose area
only partially matches the arm. In this alternative, one or more of
the arms having a corresponding arm on the other side of the wall
optionally have less than 50% of their length and/or area, matching
to an arm on the other side of the wall.
[0017] In one embodiment, all the arms do not meet an matching arm
on the other side of the wall. By having the arms not press against
each other on opposite sides of the wall, the pressure applied by
the arms may be more evenly distributed, avoiding forming high
pressure stress points on the tissue, which may result in
deterioration of tissue at the stressed point and/or may damage the
arms themselves.
[0018] An aspect of some embodiments of the present invention
relates to an anchor device adapted to be implanted across a wall
of a body organ such as the heart. The anchor device is adapted to
define an opening for blood flow with minimal contact of the blood
in the opening with the implant. The length of the opening,
measured in the perpendicular axis to the orifice plane, in which
blood passing through the opening comes in contact with the implant
is less than 3 millimeters or two millimeters. In some embodiments
of the invention, the length of the opening is less than a
millimeter or even less than half a millimeter. Optionally, the
length of the opening is substantially equal to the thickness of
the wall around the opening. In some embodiments of the invention,
the anchor device defines the opening together with the wall
tissue, such that the perimeter of the opening is mostly tissue and
only less than 20%, less than 15% or even less than 10% or 7% of
the perimeter is covered by the anchor device. Minimizing the
length of a blood passage through the opening defined by the
device, may improve washout and/or reduce residence time of the
blood in the opening, which may result in avoiding tissue growth
and/or blood clotting that will obstruct the opening.
[0019] An aspect of some embodiments of the present invention
relates to an anchor device adapted to define a passage through a
wall of a body organ such as the heart, and to be implanted in the
wall in a substantially flat configuration, in which the anchor
device has a low profile minimal protrusion out of tissue wall. The
anchor device is optionally adapted to have a thickness after
implantation substantially equal to the thickness of the wall
before implantation, for example up to 1 millimeter thicker than
the wall or even not more than half a millimeter thicker.
[0020] Optionally, in a deployed state of the anchor device its
thickness is less than 3 millimeters, less than 2 millimeters or
even less than 1 millimeter. In some embodiments of the invention,
the thin dimension of the anchor device is perpendicular to the
orifice axis and parallel the orifice plane. In some embodiments of
the invention, the thickness of the anchor device when implanted on
the wall is less than 5%, less than 2% or even less than 1% of the
maximum end to end extent of the anchor device in the flat
configuration. One potential advantage of using a flat device is
that it may allow the device to be absorbed in the wall tissue.
[0021] The term low profile refers herein to devices having a thin
dimension that does not protrude substantially above a wall on
which it is implanted. It is noted, however, that due to
irregularity of the wall, the anchor device may not conform
entirely to the surface of the wall, possibly diverging from the
wall over 20% or even 40% of the area of the anchor device. In some
embodiments of the invention, the anchor device is included in a
flat plane regardless of the form of the wall. Alternatively, the
anchor device may have a thin curved shape.
[0022] It is a feature of some embodiments of the invention that
the anchor device may serve as a base on which various units may be
mounted. These units, which are not necessary for connecting the
anchor device to the wall and holding the device in place, are not
necessarily included in the low profile of the anchor device.
[0023] In some embodiments of the invention, the anchor device is
adapted in its flat configuration to hold an orifice in the body
wall open, although the orifice is possibly blocked by a valve or
closure sheet mounted on the anchor device. For example, the anchor
device may hold the orifice open by applying a force in a radial
direction, while carrying a closure unit which blocks the orifice
in an axial direction. The anchor device optionally holds the
orifice open by having some of the parts of the device on one side
of the wall and some parts of the device on another side of the
wall and the parts on the opposite sides of the wall being
connected through the orifice.
[0024] In some embodiments of the invention, the anchoring device
is adapted for implantation in membranous tissue. Alternatively or
additionally, the anchoring device is adapted for implantation in
muscle tissue.
[0025] The anchoring device optionally defines a central orifice
which remains clear from portions of the anchoring device and/or
elements mounted thereon, along the length of the anchor device.
Optionally, in its deployed configuration, the device includes a
plurality of petal shaped elements (referred to herein as petals)
extending radially from the central orifice, some of which petals
are adapted to be located on one side of the wall and others on the
other side of the wall.
[0026] In some embodiments of the invention, the anchoring device
is formed using a minimal number of pieces (e.g., less than 5),
requiring a minimal number of welds or other attachments.
Optionally, the device is formed basically of a single elongate
piece, e.g., a single wire. In an exemplary embodiment of the
invention, the device is produced from a sheet by removing excess
material, using a suitable cutting method (e.g., laser, water jet,
chemical etching).
[0027] The anchoring device optionally does not include sharp
points, such as pins or spikes, adapted to penetrate the tissue in
order to fasten to the wall. In some embodiments of the invention,
the anchoring is performed without penetrating the tissue.
Alternatively, spikes may be used to add to the strength of the
bonding to the wall.
[0028] An aspect of some embodiments of the present invention
relates to an anchor device adapted to self expand from a folded
state in which the anchor device has a first cross-section area to
a deployed state in which the anchor device defines an orifice
having a second cross-section area substantially larger than the
first cross-section area. Optionally, the anchor device is adapted
to be implanted in an orifice in a wall of a body organ such as the
heart.
[0029] In some embodiments of the invention, the second cross
section area is at least 50%, 100% or even by at least 150% greater
than the first area. Alternatively or additionally, the diameter of
the orifice defined by the anchor device in the deployed state is
at least 20%, 30%, 50% or even at least 100% larger than the
diameter in the folded state.
[0030] In an exemplary embodiment of the invention, the anchor
device is delivered in a delivery tool (e.g., a delivery sheath)
having a diameter of less than 12 French or even less than 10
French (e.g., 8 French). The anchor device is optionally inserted
into a previously dilated orifice with a diameter close to that of
the delivery tool, which orifice is expanded by the anchor device
to a diameter of at least 12 French, or even to a diameter of 15
French, for example about 18 French. In an exemplary embodiment of
the invention, the anchor device is adapted to expand from a
diameter of about 4 millimeters when inserted into a deployed state
in which it defines an orifice having a diameter of at least 6
millimeters.
[0031] In some embodiments of the invention, the dimensions of the
orifice defined by the anchor device depend on the thickness and
structure of the wall tissue.
[0032] The anchoring device may be adapted to keep the orifice open
or may carry a flap or other unit which is adapted to close the
orifice some times or all the time or may carry a tube, cardiac
assist device, a sensor or any other device.
[0033] An aspect of some embodiments of the invention relates to a
method of perforating an orifice in the septum. The method includes
puncturing a small orifice in the septum, inserting an expandable
unit into the punctured orifice and expanding the expandable unit
to increase the size of the orifice. In some embodiments of the
invention, the expandable unit comprises a balloon. Alternatively
or additionally, the expandable unit comprises an implant which is
implanted in the orifice and remains in the orifice for at least a
day, a week or even a month after expanding the orifice.
[0034] In some embodiments of the invention, the punctured orifice
before expansion has a diameter of less than 3 millimeters, less
than 2 millimeters or even not more than 1 millimeter.
[0035] Optionally, the anchor device expands most of its expansion
upon being released from a delivery tool on which it is brought to
the orifice. Alternatively or additionally, the anchor device is
adapted to continue its expansion minutes, hours or even days after
it is implanted in the hole.
[0036] An aspect of some embodiments of the present invention
relates to a valve adapted for implantation in a human body in a
minimally invasive procedure, formed of an anchoring unit adapted
to define a blood passage, and a single flap which covers the
entire blood passage. Using a single flap for the valve may make
the valve simpler and/or more robust. In some embodiments of the
invention, using a single flap directs the blood flow passing
through the orifice in an angle relative to the orifice, possibly
even perpendicular to the flap, and thus generates in some of these
embodiments, a washout flow in a direction different from the
primary flow. In addition, the use of a single large flap may allow
easier viewing of the flap operation using medical imaging
modalities, such as fluoroscopy and ultrasound imaging.
[0037] The blood passage may be defined by the anchoring unit
itself, such that along the blood passage the blood comes in
contact substantially only with the anchoring unit, or by the
anchoring unit together with human tissue, such that blood passing
through the blood passage contacts both human tissue and the
anchoring device.
[0038] In some embodiments of the invention, the flap has an area
at least 20%, 40%, 70% or even at least 100% greater than the area
of the blood passage, Using a flap substantially larger than the
blood passage may provide a better closing of the blood passage
and/or assure overlap and seal in a relatively flexible and
compliant organ. In addition, the large flap may make it easier to
open the flap and/or may add to the stability, predictability
and/or accuracy of the valve's performance. In some embodiments of
the invention, the flap has an area even 120% or 150% greater than
the blood passage.
[0039] Possibly, a flat sheet, for example having a disc like shape
with an orifice larger than the blood passage (referred to herein
as a skirt) radially surrounds the blood passage, parallel to the
cross section of the orifice. In some embodiments of the invention,
the flap is adapted to close against the skirt, such that the skirt
optionally protects tissue underneath it from being hit by
movements of the flap and/or prevents tissue growth toward the
flap. Optionally, the skirt has a width of at least 1 millimeter or
even at least two millimeters. In some embodiments of the
invention, larger widths of the disc shape are used, for example
with a width of at least 5 or even 9 millimeters. Using a large
width is expected to prevent cell growth on the skirt. The skirt
optionally has a thickness of at least 0.5 millimeters or even at
least 0.8 millimeters, which thickness is expected to prevent
tissue growth and wrapping on the skirt. Optionally, the distance
from the outer edge of the blood passage to the inner edge of the
skirt is at least 1 or even at least 2 millimeters, in order to
prevent tissue growth in the blood passage.
[0040] An aspect of some embodiments of the present invention
relates to a valve adapted for implantation in a human body in
which a flap of the valve has a hinge substantially remote from the
passage covered by the flap. A single flap may cover the entire
passage or a plurality of flaps may cooperate to cover the passage.
A remote hinge allows for a safe location of the hinge, where it
does not obstruct blood flow through the orifice. In addition, when
the movement of the flap is based on the spring properties of an
arm holding the flap, a long arm provides a low spring
constant.
[0041] In some embodiments of the invention, a maximal curvature
point of the hinge of the flap is at least 1 millimeter, at least 3
millimeters or even at least 5 millimeters or 10 millimeters away
from the passageway blocked by the flap. Optionally, the hinge of
the flap is separated from the blocked passageway by at least 20%,
40% or even 60% of an end to end extent (referred to herein as the
diameter even in non circular shapes) of the cross-section of the
passageway.
[0042] The hinge optionally extends over a long length of an arm
carrying the flap. In such cases when a distance from the hinge is
referred to herein, the distance relates to a distance to a maximal
curvature point along the hinge. In some embodiments of the
invention, the arm is produced with a single hinge. Alternatively,
the arm carrying the flap has a plurality of weak points adapted to
serve as hinges. In some embodiments of the invention, an integral
pivot point of the arm is located in the hinge, optionally close to
the maximal curvature point of the hinge. Alternatively to a U
shaped hinge in an arm, other hinges may be used, such as a hinge
formed of a rotating pin.
[0043] An aspect of some embodiments of the present invention
relates to a valve adapted for implantation in a human body in
which a flap of the valve has a hinge around which it moves between
an open and a closed state. The valve also includes a movement
restrictor separate from the hinge, which restricts the movement of
the flap.
[0044] Optionally, the movement restrictor limits at least some
movements of the flap allowed by its mounting at the hinge. In some
embodiments of the invention, the movement restrictor prevents
movements of the flap due to large pressures on the valve, above an
allowed level. Alternatively or additionally, a movement restrictor
connects the flap to a different point on the valve, in a manner
which does not limit the movement of the flap at the hinge, but
restricts movement of the flap if the mounting at the hinge
breaks.
[0045] In some embodiments of the invention, a wire, string or
other stopper is positioned in the opening direction of the flap at
a position which blocks or at least restricts the movement of the
flap beyond the position. Alternatively or additionally, the wire,
string and/or stopper is positioned in a manner which restricts the
closing of the flap, forcing the flap to be in a partially open
state. Further alternatively or additionally, a thin flexible
element, such as a wire or string connects the flap to a stationary
point, in a manner which prevents undesired movements of the flap.
In some embodiments of the invention, the thin flexible element is
connected along an arm of the flap, attached to the flap. In some
embodiments of the invention, a spring is used instead of or in
addition to the thin flexible element.
[0046] An aspect of some embodiments of the present invention
relates to a valve adapted for implantation in a human body
including a flap held by an arm including a hinge. The arm of the
flap is adapted to be spread out over the hinge of the arm to an
angle of more than 150.degree., more than 165.degree., or even
substantially 180.degree.. In some embodiments of the invention,
the arm is adapted to be spread out during delivery, before being
put into operation.
[0047] An aspect of some embodiments of the present invention
relates to an orifice closing device adapted for use within a human
body. The closing device is formed of an anchoring portion which
defines an orifice and a closing portion which is adapted to seal
the orifice upon deployment, without the aid of tissue growth on
the closing device.
[0048] In some embodiments of the invention, the anchoring portion
is adapted to contact tissue surrounding the orifice in at least
two, three or even at least five points. The relative positions of
the points at which the anchoring portion is adapted to contact
tissue are optionally predetermined before deployment. In some
embodiments of the invention, the positions of the contact points
are only partially predetermined, for example when the anchoring
portion is elastic.
[0049] The anchoring portion is optionally a single unit connected
at one or more points to the closing portion. Alternatively, the
anchoring portion comprises a plurality of separate anchors, which
are separately connected to the closure device.
[0050] The closing portion optionally covers a larger area than an
orifice defined by the anchoring portion, in order to achieve a
tight seal. Optionally, the area covered by the closing portion is
at least 10%, 20% or even at least 40% greater than the maximal
orifice defined by the anchoring portion.
[0051] In some embodiments of the invention, the closing device is
adapted for use in percutaneous procedures, optionally being
deliverable through a catheter having a maximal diameter of less
than 18 French or even less than 12 French.
[0052] An aspect of some embodiments of the present invention
relates to a method of treatment of humans in which an orifice is
closed by percutaneously bringing a closure device to an orifice
and implanting the closure device in the orifice in a manner which
seals the orifice substantially immediately (e.g., less than a
minute or even less than ten seconds) upon deployment. The term
seal refers herein to a state in which no blood or very little
blood (e.g., less than 10 milliliters prer minute) passes through
the orifice.
[0053] An aspect of some embodiments of the present invention
relates to an orifice closing device for closing an orifice in a
tissue wall of a human, which comprises an opening unit adapted to
hold the orifice open and a cover unit adapted to at least
partially cover the orifice.
[0054] In some embodiments of the invention, the cover unit
entirely covers the orifice and prevents flow of blood through the
orifice. Alternatively or additionally, the cover unit comprises a
mesh which covers the orifice but allows flow therethrough.
Optionally, the mesh supports and/or serves as a scaffold for
tissue growth. In some embodiments of the invention, the density of
the mesh is selected to achieve a desired rate of tissue growth
thereon. Further alternatively or additionally, the cover unit has
one or more orifices defined therein.
[0055] An aspect of some embodiments of the present invention
relates to a method of closing an orifice in a body organ. The
method includes implanting in the orifice a valve including a
bio-degradable material which maintains the valve in an open
position or in a state in which it may open and close. As the
bio-degradable material dissolves or after it dissolves, the valve
changes to a permanently closed state.
[0056] In some embodiments of the invention, the bio-degradable
material (e.g., Poly Ethylene Glycol(Peg)) prevents tissue growth
on one or more portions of the valve. After the bio-degradable
material dissolves, tissue growth on the valve closes the valve
permanently and thus closes the orifice.
[0057] Optionally, the bio-degradable material dissolves after more
than 24 hours, more than 3 days or even more than a week or a
month.
[0058] In some embodiments of the invention, the valve is coated by
a material which increases tissue growth, such as vascular
endothelial growth factor (VEGF). Alternatively, the valve has
rough surfaces which encourages tissue growth. The surface and/or
materials that induce tissue growth are optionally coated by the
bio-degradable material, such that they do not come in contact with
tissue until the bio-degradable material has dissolved. The
inducement of tissue growth may be on moving parts of the valve,
for example, in order to quickly disable the valve, or on
non-moving parts, possibly allowing more time until the orifice
closes permanently.
[0059] Alternatively or additionally, the bio-degradable material
forms a stopper that prevents the valve from closing until it
dissolves.
[0060] An aspect of some embodiments of the present invention
relates to a method of closing an orifice within a heart. The
method includes diagnosing a patient to determine a desired time
and/or rate at which to close the orifice and selecting a valve
having a desired closure profile. The selected valve is then
implanted in the patient and gradually moves to a permanently
closed state.
[0061] In some embodiments of the invention, the rate at which the
valve closes is controlled by selecting an amount and/or type of a
bio-degradable material which delays the movement of the valve to a
permanently closed state. Alternatively or additionally, the rate
at which the valve closes is controlled by selecting an amount,
location and/or type of a tissue growth enhancement drug. Further
alternatively or additionally, the rate at which the valve closes
is controlled by selecting dimensions and/or structures of surfaces
of the valve. For example, a mesh structure or density may be
selected to control tissue growth. Alternatively or additionally, a
roughness level of one or more surfaces may be selected.
[0062] In some embodiments of the invention, the valve is used in
CHF patients and is adapted to gradually close only if it has not
encountered high pressures for over a predetermined time. If,
however, the valve encounters high pressures, the flow through the
valve washes off beginnings of tissue growth and prevents permanent
closure due to tissue growth. Thus, if after a while of operation
the patient is cured, the valve closes and is covered by tissue.
Optionally, the time for which the valve needs to not encounter
high pressures until it closes is a feature of the valve and may be
adjusted, for example, by setting the roughness of surfaces of the
valve, drug amounts and/or the amount of blood it passes when it
does not under high pressures.
[0063] Optionally, in accordance with these embodiments, if
although the patient did not suffer from high pressures, a
physician determined that it is too early to allow the valve to
permanently close, an override mechanism may be applied from
outside the patient in order to open the valve, for example using
magnetic or RF coupling, and thus restart the counting of the
period until closure. Alternatively or additionally, the valve is
adapted to open when the patient performs special exercises and/or
other activities, which the patient may be instructed to perform to
prevent closure.
[0064] Optionally, a kit of closure devices includes a plurality of
closure devices which are each marked with an average closure time
and/or an opening pressure threshold.
[0065] An aspect of some embodiments of the present invention
relates to a method of closing an orifice within a heart. The
method includes implanting a valve which is adapted to open and
close in the patient's heart and at a later time moving the valve
to a state in which it is permanently closed by an external
intervention.
[0066] In some embodiments of the invention, the external
intervention is performed by magnetic or RF coupling which is used
to change the conditions governing the opening of the valve.
Alternatively or additionally, the external intervention includes a
percutaneous procedure which accesses the valve to change its
operation parameters.
[0067] An aspect of some embodiments of the present invention
relates to a method of treating an aneurism, for example a septal
aneurism. The method includes perforating an orifice in the
aneurism and implanting a closure device in the perforated orifice.
The closure device strengthens the wall including the aneurism and
this avoids the problems associated with the aneurism.
[0068] An aspect of some embodiments of the present invention
relates to a delivery tool, for delivering a thin element into a
patient. The tool includes a central rod, a partially cut tube and
an external channel, which surrounds the rod and tube. Delivering a
flat element using the delivery tool comprises confining the flat
element between the central rod and the partially slotted tube and
delivering the tube within a channel which prevents the tube from
expanding and releasing the flat element. When the flat element is
at its desired location, the channel is refracted relative to the
slotted tube, the tube is allowed to expand and releases the flat
element.
[0069] In some embodiments of the invention, the flat element is a
springy element which is held forcefully in the tube. Upon release
of the tube from the channel, the springy element exits the tube
radially relative to a long axis of the elongate tube,
perpendicular to the tube.
[0070] In some embodiments of the invention, the delivery tool
comprises a percutaneous tool, such as a minimally invasive tool, a
catheter or a laparoscope.
[0071] An aspect of some embodiments of the present invention
relates to a delivery device for leading an implant including one
or more loops into a human body. The delivery device includes one
or more protrusions which hold the loop between an inner core and
an outer channel. As long as the inner core is within the outer
channel, the one or more loops of the implant are held by the
protrusion. When, however, the inner core is moved beyond the outer
channel, the loops are released from the protrusion.
[0072] In some embodiments of the invention, until release, the
protrusions are adapted to engage the loops in a manner which
allows both pull and push the implant.
[0073] The implant is optionally mounted into the delivery device
in a collapsed state in a manner in which at least portions of the
implant are allowed to expand upon release from the channel. In
some embodiments of the invention, at least some portions of the
implant are allowed to expand without the protrusion releasing one
or more of the loops. Optionally, as long as the loop is not
released from the protrusion, the expanded portions can be
re-collapsed by pulling the implant backwards.
[0074] An aspect of some embodiments of the present invention
relates to a method of mounting an implant including one or more
arms into a delivery tube. The implant is originally packaged in a
separate magazine of a diameter substantially equal to the diameter
of the delivery tube. The magazine is optionally inserted into a
proximal port of the delivery tube, e.g., a haemostatic valve, and
the implant is pushed therein from the magazine to the delivery
tube.
[0075] An aspect of some embodiments of the present invention
relates to an implant including a plurality of arms, which includes
a string or wire connecting between a plurality of the arms. The
string is attached to the arms such that pulling on the string
collapses the implant and introduces the implant back into a
removal tube, which may be a same tube used for delivery of the
implant or a different tube.
[0076] In some embodiments of the invention, the implant includes
distal and proximal arms and the string connects to each of the
proximal arms. Optionally, the string has a central point at which
string portions connecting to all the proximal arms meet.
[0077] An aspect of some embodiments of the present invention
relates to an implant including a plurality of arms having
different lengths. Optionally, the arms define loops which may be
held by a delivery device during delivery. In some embodiments of
the invention, the implant includes at least three or even at least
four arms of different lengths. Optionally, the arms of different
lengths are adapted to be included in a single plane in a deployed
state of the implant and/or are adapted to be directed in a single
direction in a folded state, for delivery.
[0078] An aspect of some embodiments of the present invention
relates to a delivery tool for delivering an implant into a human
body. The delivery tool includes an outer channel and an inner rod
adapted to engage arms of an implant together with the channel.
Pushing the rod distally releases the arms when the point at which
they are held is pushed beyond the distal end of the channel. The
rod is adapted to engage the arms of the implant at different
points along the length of the rod's distal portion, such that
pushing the rod distally within the channel gradually releases the
arms.
[0079] An aspect of some embodiments of the present invention
relates to a method of delivering an implant having a plurality of
arms in a percutaneous and/or minimally invasive procedure. The
method includes separately releasing the arms until a last arm is
released and the implant moves into place.
[0080] An aspect of some embodiments of the present invention
relates to a delivery tool for delivering an implant including a
plurality of arms, the delivery tool including a coil adapted to
receive the arms. Rotation of the coil optionally separately
releases the arms.
[0081] An aspect of some embodiments of the present invention
relates to an implant including a plurality of arms adapted to
participate in anchoring the implant to internal body tissue and a
flat sheet fixed to the arms. Optionally, the length of the arms is
fixed parallel to the sheet. In some embodiments of the invention,
the arms are embedded within the skirt.
[0082] In some embodiments of the invention, the implant defines an
orifice in the a wall to which it anchors and the sheet does not
cover the orifice.
[0083] Optionally, the sheet is coated to prevent tissue growth on
the sheet. Alternatively, the sheet is coated to induce tissue
growth thereon.
[0084] In some embodiments of the invention, the implant includes a
flap that is adapted to close against the sheet, and the sheet
serves to protect tissue from the flap's contact as it closes.
[0085] An aspect of some embodiments of the invention relates to a
valve adapted to be implanted in internal tissue of a patient. The
valve is adapted to open under pressures normally encountered
during the cardiac cycle in patients between the right and left
atrium, for a first duration of the cardiac cycle and under higher
pressures for a second duration of the cardiac cycle different from
the first duration.
[0086] Optionally, the valve is adapted to open for a larger
percentage of the cardiac cycle under pressures encountered between
the right and left atrium in patient's under stress than under
pressures in normal conditions between the right and left
atrium.
[0087] In an exemplary embodiment of the invention, the valve is
adapted to open in a healthy patient for less than 100 milliseconds
or even less than 50 milliseconds in each cardiac cycle. In a
patient under a high pressure episode, the valve optionally opens
for at least 150 milliseconds, 200 milliseconds or even at least
400 milliseconds in each cardiac cycle. Optionally, the valve is
adapted to open at a pressure of at least 2 mmHg, 4 mmHg or even at
least 6 mmHg. In some embodiments of the invention, the valve is
adapted to open at a pressure difference of at least 6 mmHg or even
at least 10 mmHg.
[0088] In some embodiments of the invention, when implanted between
the right and left atrium, the valve is adapted to pass during the
second duration at least 50% more blood than during the first
duration. Optionally, during the second duration, the valve is
adapted to shunt blood at a rate of at least 600 or even at least
800 milliliters per minute, while during the first duration the
valve is adapted to shunt blood at a rate of less than 400 or even
less than 300 milliliters per minute.
[0089] There is therefore provided in accordance with an exemplary
embodiment of the invention, a medical implant, comprising an
anchor portion including a plurality of arms adapted to engage an
internal tissue wall of a body from two opposite faces, wherein the
anchor portion is configured such that at least one of the arms
does not have an entirely overlapping arm on the other side of the
wall and an opening portion adapted to define an opening for blood
flow through the internal tissue wall, when the anchor portion
engages the wall.
[0090] Optionally, the opening portion is adapted to radially
expand in changing from a collapsed state to a deployed state.
Optionally, a largest end to end extent of the anchor portion in a
deployed state is at least twice the largest end to end extent of
the opening defined by the opening portion. Optionally, a largest
end to end extent of the anchor portion is at least four times the
largest end to end extent of the opening defined by the opening
portion. Optionally, the opening portion comprises a ring
surrounding the defined opening. Optionally, the anchor portion and
opening portion are configured to have a low profile of less than 3
millimeters in a deployed state not on a tissue wall. Optionally,
the plurality of arms comprise flexible elongate elements and/or
petals. Optionally, in the deployed state at least one of the arms
does not have an even a partially overlapping arm on the other side
of the wall, Optionally, the arms are configured to surround the
orifice in a deployed state and wherein most of the arms are
neighbored along a line surrounding the orifice by two arms
configured to be on an opposite side of the wall.
[0091] Optionally, most of the arms of the anchoring portion do not
have arms overlapping them on the other side of the wall, in the
deployed state. Optionally, the anchor portion and the opening
portion are comprised in a single element. The medical implant
optionally includes a mesh mounted on the opening portion.
[0092] There is further provided in accordance with an exemplary
embodiment of the invention, a medical implant optionally includes
a valve mounted on the anchor portion in a manner which regulates
flow through an opening defined by the opening portion.
[0093] Optionally, the valve is formed together with the anchor
portion from a same sheet, wire or tube. Optionally, the valve is
at least partially formed from a different material from the anchor
portion. Optionally, portions of the implant are covered by ePTFE
or polyurethane.
[0094] The medical implant optionally includes a motor mounted on
the anchor portion and adapted to control the valve. The medical
implant optionally includes a sensor mounted on the anchor
portion.
[0095] There is further provided in accordance with an exemplary
embodiment of the invention, a medical implant, comprising an
anchor portion adapted to attach to internal tissue of a body; and
an opening portion adapted to define an opening for blood flow when
deployed within the body, which opening has a length of less than 3
millimeters, in which blood passing through the opening comes in
contact with the implant.
[0096] Optionally, the anchor portion includes a plurality of arms
adapted to be located on opposite sides of the attach to the tissue
by including parts adapted to be located on opposite sides of a
tissue wall. Optionally, the anchor portion comprises a plurality
of elongate elements extending radially from the opening portion,
wherein a first group of the elongate elements are adapted to be
located on one side of the wall and a second group of the elongate
elements is adapted to be located on a second side of the wall.
[0097] Optionally, each of the first and second groups comprises at
least three elongate elements. Optionally, at least some of the
elongate elements comprise petal and/or hoof shaped elements.
Optionally, the anchor portion and opening portion are formed from
a single piece. Optionally, the implant has a collapsed state and a
deployed state and wherein the opening portion is adapted to apply
a radial force when released from the collapsed state. Optionally,
the opening portion is adapted to cover less than 20% of the
perimeter of the opening it defines. Optionally, the anchor portion
is configured to engage a tissue wall such that a length in which
blood passing through the opening comes in contact with the implant
is less than 1 millimeter thicker than the wall. Optionally, the
anchor portion and opening portion are configured to have in a
deployed state a low profile of less than 3 millimeters.
Optionally, the anchor portion and opening portion are configured
to have a low profile of less than 15% of an end to end extent of
the anchor portion in a deployed state. Optionally, the anchor
portion and opening portion are configured to have a low profile of
less than 10% of an end to end extent of the anchor portion in a
deployed state. Optionally, in the deployed state, the implant does
not include parts within the opening defined by the opening
portion, beyond parts of the opening portion defining the opening.
Optionally, implant optionally includes a skirt surrounding the
opening defined by the opening portion.
[0098] Optionally, the implant includes a closure unit adapted to
block blood flow through the opening. Optionally, the closure unit
is part of a valve which controls the extent of blood flow through
the opening. Optionally, the anchor portion does not include sharp
points. Optionally, the anchor portion includes at least one spike
adapted to penetrate the tissue.
[0099] There is further provided in accordance with an exemplary
embodiment of the invention, a medical implant, comprising an
anchor portion adapted to attach to an internal tissue wall of a
body; and an opening portion adapted to define an opening in the
wall, wherein the implant is configured to have a low profile of
less than 5 millimeters in a released state in which it is not
subject to external forces.
[0100] Optionally, the implant is configured to have a low profile
of less than 12% of its largest end to end length in its released
state. Optionally, the anchor portion and opening portion are
configured to have a low profile of less than 8% of an end to end
extent of the anchor portion in the released state. Optionally, the
implant is configured to have a low profile not adding to the
thickness of the wall more than a millimeter in a deployed state in
which the anchor portion is attached to the wall. Optionally, the
anchor portion does not include sharp spikes. Optionally, the
anchor portion includes a plurality of arms adapted to be located
on opposite sides of the tissue wall and to engage the tissue wall
between them. Optionally, the anchor portion and opening portion
are formed from a single sheet, tube or wire. Optionally, the
implant has a collapsed state and a deployed state and wherein the
opening portion is adapted to apply a radial force when released
from the collapsed state. Optionally, in the deployed state, the
implant does not include parts within the opening defined by the
opening portion, beyond parts of the opening portion defining the
opening. Optionally, the opening portion is adapted to cover less
than 40% of the perimeter of the opening it defines.
[0101] Optionally, the implant is configured to have a low profile
of less than 2.5 millimeters in a released state in which it is not
subject to external forces. Optionally, the implant is configured
to have a low profile of less than 1 millimeters in a released
state in which it is not subject to external forces. Optionally,
the anchor portion comprises a plurality of arms adapted to engage
a tissue wall from opposite sides and wherein in the released state
a height difference between the arms is less than 2
millimeters.
[0102] Optionally, the anchor portion comprises a plurality of arms
adapted to engage a tissue wall from opposite sides and wherein in
the released state the arms intended for the different sides of the
wall are in the same plane.
[0103] There is further provided in accordance with an exemplary
embodiment of the invention, a medical implant, comprising an
anchor portion adapted to attach to an internal tissue wall of a
body; and an opening portion adapted to define an opening in the
wall, wherein the implant is configured to have a collapsed state
in which the implant is contained in a cylinder shape of a first
diameter, and a deployed state in which the anchor portion engages
the wall and the opening portion has a rest state in which it
defines an orifice having a second diameter larger than the first
diameter.
[0104] Optionally, the implant is adapted to self expand from the
collapsed state to the deployed state. Optionally, the second
diameter is larger than the first diameter by at least 50%.
[0105] There is further provided in accordance with an exemplary
embodiment of the invention, a method of placing an implant in an
orifice in a tissue wall in a body, comprising inserting the
implant into the orifice in a collapsed state, releasing the
implant so that it engages the tissue wall and allowing the implant
to elastically expand while engaging the wall, such that it
radially expands within the orifice and expands the orifice.
Optionally, the implant expands the diameter of the orifice by at
least 20%. Optionally, inserting the implant into the orifice
comprises inserting into an orifice in a septum.
[0106] Optionally, inserting the implant into the orifice comprises
inserting into an orifice made less than six hours before inserting
the implant. Optionally, inserting the implant into the orifice
comprises inserting into an orifice existent in the patient for at
least a week.
[0107] There is further provided in accordance with an exemplary
embodiment of the invention, a medical valve for implant in a human
body, comprising an anchor portion adapted to attach to internal
tissue of a body, an opening portion adapted to define an opening
for blood flow and a single flap adapted to control the amount of
blood flowing through the opening defined by the opening
portion.
[0108] Optionally, the single flap is adapted to have a closed
state in which substantially no blood can flow through the opening.
Optionally, the single flap has at least one orifice in the flap
which allows flow through the opening even when the flap is in a
closed state covering the opening. The valve optionally includes a
stopper adapted to prevent the flap from entirely covering the
opening defined by the opening portion. Optionally, the single flap
has an area at least 10% greater than the cross-section area of the
opening. Optionally, the single flap is mounted on an arm with a
hinge having a maximal curvature point distanced from the opening
defined by the opening portion by more than 0.5 millimeters or even
more than five millimeters. Optionally, the single flap is mounted
on an arm with a hinge having a maximal curvature point distanced
from the opening defined by the opening portion by more than a
diameter of the opening. Optionally, the single flap is mounted on
an arm with a hinge having a maximal curvature point distanced from
a distal point of the anchor portion by more than 1 millimeter.
Optionally, the single flap is mounted on an arm with a hinge
having a maximal curvature point distanced from a distal point of
the anchor portion by more than five millimeters.
[0109] Optionally, the valve is configured to open and close
without bending the single flap in an area covering the opening.
Optionally, the single flap is coated by a bio-degradable material.
Optionally, the single flap is formed of a metal coated by a
polymer. Optionally, the single flap is made of nitinol.
Optionally, the single flap comprises a frame and a sheet carried
by the frame. Optionally, the single flap and anchor portion are
formed in a monolithic process. Optionally, the single flap and
anchor portion are produced separately and then combined.
Optionally, the single flap is mounted on the anchor portion
through an arm having a plurality of weak points adapted to serve
as hinges. Optionally, the single flap is mounted on the anchor
portion through an arm with an angle of at least 30.degree. between
the flap and the arm in a closed state of the flap. Optionally, the
single flap is mounted on the anchor portion through a plurality of
arms.
[0110] There is further provided in accordance with an exemplary
embodiment of the invention, a medical valve for implant in a human
body, comprising an anchor portion adapted to attach to internal
tissue of a body, an opening portion adapted to define an opening
for blood flow, a flap adapted to cover at least a portion of the
opening; and an arm connecting the flap to a hinge at least 1
millimeter away from the opening. Optionally, the hinge is
distanced from the opening by more than 3 millimeters. Optionally,
the hinge is distanced from the anchor portion by more than 3
millimeters. Optionally, the flap and arm are formed as a single
piece. Optionally, the arm, anchor portion and opening portion are
formed as a single piece. Optionally, the arm is folded in a manner
which forms a hinge around which the flap opens and closes.
Optionally, the arm is adapted to be stretched out during delivery
into the patient such that the arm around the maximal curvature
point of the hinge has an angle of at least 160.degree..
Optionally, the arm comprises a plurality of arms.
[0111] There is further provided in accordance with an exemplary
embodiment of the invention, a medical valve for implant in a human
body, comprising an anchor portion adapted to attach to internal
tissue of a body, an opening portion adapted to define an opening
for blood flow, a flap adapted to controllably cover at least a
portion of the opening, a hinge on which the flap moves between an
open state and a closed state in which it covers the opening and a
movement restrictor separate from the hinge, adapted to restrict
the movement of the flap.
[0112] Optionally, the valve is adapted to be delivered into a body
in a percutaneous procedure, for example through a catheter.
Optionally, the movement restrictor comprises a thin flexible
element stretched behind the flap in a manner which limits its
movement away from the opening portion. Optionally, the thin
flexible element is connected at a plurality of points to the
anchoring portion or to a skirt mounted on the anchoring portion.
Optionally, the movement restrictor comprises a thin flexible
element which connects the flap or an arm connecting the flap to
the hinge, to the anchor portion or another element which does not
move with the flap. Optionally, the movement restrictor is
configured to restrict movement of the flap only if another portion
of the valve fails. Optionally, the movement restrictor comprises a
tab or sheet.
[0113] There is further provided in accordance with an exemplary
embodiment of the invention, a medical valve for implant in a human
body, comprising an anchor portion adapted to attach to internal
tissue of a body, an opening portion adapted to define an opening
for blood flow, a flap adapted to controllably cover at least a
portion of the opening and an arm connecting the flap to the anchor
portion, wherein the arm is adapted to have an operation state in
which it is folded and defines a hinge for the flap and a delivery
state in which the arm has an angle of at least 150 degrees at the
hinge.
[0114] Optionally, the arm is adapted to have an angle of
substantially 180 degrees at the hinge in the delivery state.
[0115] There is further provided in accordance with an exemplary
embodiment of the invention, an orifice closing implant, comprising
an opening portion adapted to define an opening for blood flow in
internal tissue of humans and to hold the opening open; and a cover
mounted on the opening portion and covering the opening.
[0116] Optionally, the cover and opening portion are adapted to be
delivered together into a patient in a percutaneous procedure.
Optionally, the cover is adapted to seal the opening defined by the
opening portion. Optionally, the opening portion is adapted to
anchor the implant to the internal tissue. Optionally, the cover
comprises at least one hole allowing blood flow therethrough.
Optionally, the cover comprises a mesh pre-attached to the opening
portion.
[0117] Optionally, the cover comprises a material which encourages
tissue growth. Optionally, the cover and anchor portion are
produced separately and later combined. Optionally, the cover and
anchor portion are produced together in a monolithic process.
Optionally, the cover and anchor portion are produced from
different materials.
[0118] There is further provided in accordance with an exemplary
embodiment of the invention, an orifice closing implant, comprising
an anchoring portion adapted to connect to tissue within a patient
and define an opening for blood flow in internal tissue of humans;
and a closing portion adapted to seal the opening upon deployment
without the aid of tissue growth, the closing portion and the
anchoring portion are adapted to be delivered together into a
patient in a percutaneous procedure.
[0119] Optionally, the closing portion has an area at least 20%
greater than the opening defined by the anchoring portion.
Optionally, the anchoring portion is connected to the closing
portion in at least three points.
[0120] There is further provided in accordance with an exemplary
embodiment of the invention, a method of closing an orifice in
internal human tissue, comprising bringing a closure device to an
orifice in a percutaneous procedure; and placing the closure device
on the orifice in a manner which seals the orifice immediately upon
placement.
[0121] There is further provided in accordance with an exemplary
embodiment of the invention, an implant, comprising a valve adapted
for implantation in a patient; and a bio-degradable material placed
on the valve in a manner which prevents permanent closure of the
valve and in a manner which slowly dissolves when the valve is
implanted in a patient.
[0122] Optionally, the valve is adapted to be delivered to an
internal body organ in a percutaneous procedure. Optionally, the
bio-degradable material is adapted to dissolve over a period longer
than a week. Optionally, the bio-degradable material prevents
tissue growth.
[0123] Optionally, at least one surface of the valve is coated by a
drug which enhances tissue growth, and the drug is coated by a
bio-degradable material which delays the tissue growth until it is
dissolved. Optionally, the biodegradable material forms a stopper
which prevents closing of the valve. Optionally, the valve is
adapted to move to a permanently closed state due to its
interaction with body tissue, after the biodegradable material
dissolves.
[0124] There is further provided in accordance with an exemplary
embodiment of the invention, a method of closing an orifice in the
blood system of a patient, comprising diagnosing a patient to
determine a desired closure profile of an internal orifice,
selecting a valve responsive to the determined closure profile and
implanting the selected valve in the internal orifice, such that
after implantation the valve is adapted to open and close and
allowing the selected valve to change to a permanently closed
state.
[0125] Optionally, selecting the valve comprises selecting a valve
having an average time between implantation and permanent closure
closest to a desired time for the patient.
[0126] Optionally, implanting the valve comprises implanting in a
percutaneous procedure. Optionally, selecting the valve comprises
selecting a valve which includes a biodegradable material which
delays the movement to permanent closure. Optionally, selecting the
valve comprises selecting a valve having one or more surfaces
adapted to encourage tissue growth. Optionally, selecting the valve
comprises selecting a valve which moves to a permanently closed
state if the valve is not opened for at least a predetermined
amount of time. Optionally, selecting the valve comprises selecting
a valve adapted to change to the permanently closed state not less
than a month after implantation.
[0127] There is further provided in accordance with an exemplary
embodiment of the invention, a method of closing an orifice in the
blood system of a patient, comprising implanting a valve in the
patient such that closing the valve prevents passage of blood
through the orifice and changing a state of the valve to a state in
which it is permanently closed and does not allow passage of blood.
Optionally, moving the valve to the state in which it is
permanently closed comprises transferring the valve to the
permanently closed state at least a week after implanting the
valve.
[0128] Optionally, the valve opens and closes a plurality of times
before moving to the permanently closed state. Optionally,
implanting the valve comprises implanting a valve coated by a
bio-degradable material which prevents tissue growth on the valve.
Optionally, moving the valve to the permanently closed state
comprises having tissue grow on the valve.
[0129] There is further provided in accordance with an exemplary
embodiment of the invention, a method of treating an aneurism,
comprising identifying an aneurism in a patient, perforating a hole
in the aneurism and implanting a closure device in the hole.
[0130] There is further provided in accordance with an exemplary
embodiment of the invention, a delivery tool for delivering an
implant into a patient in a percutaneous procedure, comprising a
central rod, a slotted tube along part of its perimeter at a distal
end thereof, mounted on the central rod, the tube being adapted to
receive a flat implant part between the tube and the central rod;
and an outer channel surrounding the central rod and the tube, the
channel being adapted to be retracted relative to the tube, edges
of the tube around the cut are adapted to expand the tube when the
outer channel is retracted, and allow the flat implant part to exit
the tube in a direction perpendicular to the rod.
[0131] Optionally, the tube is cut over between 10-25% of its
perimeter along at least a portion of its length.
[0132] There is further provided in accordance with an exemplary
embodiment of the invention, a delivery tool for delivering an
implant into a patient in a percutaneous procedure, comprising a
channel adapted to be placed in a blood vessel of a patient for
leading an implant to an internal organ of the patient, an elongate
rod adapted to pass into the channel; and a notched head mounted on
a distal end of the rod, the head having areas in which its radial
size is smaller than the inner cross-section of the channel, such
that a wire of an implant can fit between the notched head and the
channel and having at least one protrusion which substantially
touches the channel, such that a loop of an implant can fit around
the protrusion and can be pulled proximally by pulling the rod
proximally.
[0133] Optionally, the head comprises at least three protrusions
adapted to receive respective loops of an implant. Optionally, the
head comprises behind the at least one protrusion a protruding
ring, such that a loop head of the implant is caught between the
protrusion and the protruding ring and moving the head distally
pushes the implant distally.
[0134] There is further provided in accordance with an exemplary
embodiment of the invention, a method of delivering an implant in a
percutaneous procedure, comprising providing a delivery tool
including a channel and internal rod, mounting an implant including
arms with loops in the delivery tool, in a manner such that the
implant moves distally and radially with movements of the rod and
delivering the implant through the delivery tool to an internal
body organ; and releasing the implant in the internal body
organ.
[0135] Optionally, mounting the implant comprises mounting the
loops on a coil shaped wire. Optionally, mounting the implant
comprises mounting the loops between protrusions on a distal end of
the rod and the channel.
[0136] Optionally, releasing the implant comprises releasing a
plurality of anus together. Alternatively or additionally,
releasing the implant comprises releasing at least two of the arms
separately. Optionally, the method includes diagnosing the patient
and selecting the implant responsive to the diagnosis.
[0137] Optionally, diagnosing the patient comprises determining a
thickness of a tissue wall in the patient. Optionally, diagnosing
the patient comprises diagnosing the patient using the delivery
tool. Optionally, selecting the implant comprises selecting an
implant having a desired anchor portion responsive to the
diagnosis.
[0138] There is further provided in accordance with an exemplary
embodiment of the invention, a method of delivering an implant into
a patient, comprising providing an implant including an anchor
portion, an opening defining portion, a flap and an arm connecting
the flap to the anchor portion, mounting the implant with the arm
at least partially folded over itself; and inserting the implant
with the folded arm into a catheter channel.
[0139] Optionally, the implant is adapted to operate in a first
configuration in which the arm is folded over itself, and wherein
inserting the implant into the catheter channel comprises inserting
with the arm folded at a different point than in the first
configuration.
[0140] There is further provided in accordance with an exemplary
embodiment of the invention, a method of delivering an implant into
a patient, comprising inserting an implant into a magazine having
an inner diameter, passing the magazine into a proximal port of a
delivery tube having an inner diameter substantially the same as
the inner diameter of the magazine and advancing the implant from
the magazine into the delivery tube.
[0141] Optionally, inserting the implant into the magazine
comprises inserting the implant into the magazine in a folded state
in which arms of the implant attempt to expand and are prevented
from expanding by the magazine. Optionally, passing the magazine
into a proximal port of the delivery tube comprises passing through
a haemostatic valve.
[0142] There is further provided in accordance with an exemplary
embodiment of the invention, a medical implant, comprising an
anchor portion including a plurality of arms and a wire connecting
a group of the arms of the anchor portion in a manner which allows
folding the group of arms by pulling the wire at a single
point.
[0143] Optionally, the anchor portion has a folded state in which
it has distal and proximal arms and wherein the wire is connected
to the proximal arms. Optionally, the wire is connected to at least
three arms. Optionally, the anchor portion is adapted to self
expand from a folded state to an expanded state.
[0144] There is further provided in accordance with an exemplary
embodiment of the invention, a medical implant, comprising an
anchor portion including a plurality of arms adapted to anchor in
internal tissue of a patient; and a flat sheet fixed to the
arms.
[0145] Optionally, the plurality of arms are adapted to anchor to a
tissue wall by having some of the arms located on one side of the
walls and others of the arms on the other side of the wall.
Optionally, the plurality of arms are adapted to define a passage.
Optionally, the flat sheet is adapted to surround the passage but
not cover the passage. Optionally, the flat sheet has a disc shape.
Optionally, the inner perimeter of the flat sheet is distance from
the defined passage by at least 1.5 millimeters. Optionally, the
inner perimeter of the flat sheet is substantially leveled with the
defined passage. Optionally, the flat sheet is adapted to cover the
passage. Optionally, the plurality of arms are adapted to attach to
the sheet with their length parallel the plane of the sheet.
[0146] The medical implant optionally includes an additional sheet
on an opposite side of the anchor portion. Optionally, the
plurality of arms are adapted to attach to the sheet with some
slack, allowing for a wavy shaped skirt.
[0147] There is further provided in accordance with an exemplary
embodiment of the invention, a method of generating a hole in an
internal tissue wall of a patient, comprising puncturing a small
orifice in a tissue wall, inserting an expander into the orifice;
and applying substantially only radial forces by the expander to
expand the hole.
[0148] Optionally, the expander comprises a balloon and/or an
implant which is left in the orifice after it is expanded.
Optionally, puncturing the small orifice comprises puncturing an
orifice having a diameter of less than 2 millimeters. Optionally,
applying the radial forces comprises increasing the diameter of the
orifice by at least 20% or even by at least 50%.
[0149] There is further provided in accordance with an exemplary
embodiment of the invention, an implant for internal tissue,
comprising an anchor portion adapted to anchor the valve in a
patient and a valve adapted to open for a first percentage of the
cardiac cycle when subject to pressures between the left and right
atrium of a healthy patient and for a second percentage of the
cardiac cycle when subject to the pressures between the left atrium
and the right atrium of a patient with a high pressure level.
Optionally, the implant is adapted to open for pressures above a
threshold which is lower than 7 mmHg.
BRIEF DESCRIPTION OF THE DRAWINGS
[0150] Exemplary non-limiting embodiments of the invention will be
described with reference to the following description of the
embodiments, in conjunction with the figures. Identical structures,
elements or parts which appear in more than one figure are
preferably labeled with a same or similar number in all the figures
in which they appear, and in which:
[0151] FIG. 1 is a schematic illustration of an anchoring device in
a deployed configuration, in accordance with an exemplary
embodiment of the present invention;
[0152] FIGS. 2A-2E are schematic illustrations of implant devices,
in accordance with other exemplary embodiments of the
invention;
[0153] FIG. 3 is a schematic illustration of an implant device, in
accordance with another exemplary embodiment of the invention;
[0154] FIG. 4A is a schematic illustration of a valve formed of an
anchor device carrying a flap, in accordance with an exemplary
embodiment of the invention;
[0155] FIG. 4B is a schematic illustration of an anchor device, in
accordance with an exemplary embodiment of the invention;
[0156] FIG. 4C is a schematic graph of operation schemes of a
valve, in accordance with various exemplary embodiments of the
invention;
[0157] FIG. 5 is a schematic illustration of a flap valve, in
accordance with another exemplary embodiment of the invention;
[0158] FIGS. 6A and 6B illustrate an anchoring device, carrying a
shunt, in a deployed state and collapsed state, respectively, in
accordance with an exemplary embodiment of the invention;
[0159] FIGS. 7A-7C describe a two stage valve, in accordance with
an exemplary embodiment of the invention;
[0160] FIG. 8A is a schematic illustration of a valve, in
accordance with another exemplary embodiment of the invention;
[0161] FIG. 8B is a schematic illustration of a shunt, in
accordance with an embodiment of the present invention;
[0162] FIG. 9 is a schematic illustration of a valve, in accordance
with an exemplary embodiment of the invention;
[0163] FIGS. 10A and 10B are schematic illustrations of closure
devices, in accordance with exemplary embodiments of the
invention;
[0164] FIG. 11 is a schematic illustration of an anchoring device
holding a cannula, in accordance with an exemplary embodiment of
the invention;
[0165] FIG. 12 is a schematic top view of an implantable flow
control device, in accordance with an exemplary embodiment of the
invention;
[0166] FIG. 13 is a flowchart of acts performed in implanting an
anchoring device in a heart, in accordance with an exemplary
embodiment of the invention;
[0167] FIG. 14A is a schematic illustration of anchoring device
being mounted into a magazine, in accordance with an exemplary
embodiment of the present invention;
[0168] FIG. 14B is a schematic illustration of an anchoring device
within a magazine, in accordance with an exemplary embodiment of
the present invention;
[0169] FIG. 14C is a schematic illustration of an anchoring device
being moved from a magazine to a delivery channel, in accordance
with an exemplary embodiment of the present invention;
[0170] FIG. 14D is a schematic illustration of anchoring device
within a delivery channel in the vicinity of a wall in which it is
to be implanted, in accordance with an exemplary embodiment of the
present invention;
[0171] FIGS. 15A-15C are schematic illustrations of a handle of a
minimally invasive delivery tool, in a process of implanting an
anchoring device, in accordance with an exemplary embodiment of the
invention;
[0172] FIG. 16 is a schematic view of a distal end of a delivery
tool carrying a valve flap, in accordance with another exemplary
embodiment of the present invention;
[0173] FIG. 17 is a schematic illustration of a delivery tool, in
accordance with another exemplary embodiment of the invention;
and
[0174] FIG. 18 is a schematic illustration of an anchoring device
with a removal string, in accordance with an exemplary embodiment
of the invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
Overview
[0175] FIG. 1 is a schematic illustration of an anchoring device
100 in a deployed configuration, in accordance with an exemplary
embodiment of the present invention. Device 100 is adapted for use
within internal organs of a patient, for example in the heart.
Anchoring device 100, as well as the other anchoring device
embodiments described hereinbelow, may be used on its own to hold
an orifice open or may carry one or more functional devices, such
as a valve, a closure device, a tube and/or any other device
requiring anchoring within a patient.
[0176] While device 100 is suitable for use in many body organs, it
is especially useful for organs which move and endure varying
pressures, such as the heart. Device 100 is optionally adapted for
use in organs which are sensitive to formation of embolisms and is
designed to minimize the chances of formation of embolisms.
[0177] Device 100 comprises a single wire 102 formed into a
plurality of petals 104 (marked 104A and 104B) extending radially
from a central orifice 106, defined by an imaginary circle, ellipse
or any other shape (e.g., a polygon) connecting curve points 112,
between petals 104. Petals 104A are optionally designed to be
slightly higher than petals 104B (in the Z direction in FIG. 1),
such that when deployed within an orifice in a wall, petals 104A
are located on one side of the wall and petals 104B are on the
other side of the wall. In some embodiments of the invention, the
distance between the planes of petals 104B and pf petals 104A is
less than 3 millimeters or even less than 1.5 millimeters. In an
exemplary embodiment of the invention, the distance is about 2.5
millimeters. Alternatively, the distance is about 1 millimeter or
more. Alternatively, petals 104A and 104B are included in a single
plane, such that the profile of device 100 is equal to the
thickness of the wire 102 or sheet from which the device is
produced, for example about 0.3 millimeters or possibly even less
than 0.1 millimeters.
[0178] Curve points 112 are designed to abut against the wall
tissue facing orifice 106 and prevent the tissue from substantially
extending into central orifice 106. Thus, when located within an
orifice in a wall of the heart, the wall is caught between petals
104 and is held open by curve points 112. Curve points 112 are
optionally designed to have a relatively large curve radius, so as
to better endure the forces applied to wire 102 at the curve
points. As discussed below, a wire of the same material as wire 102
or a different material such as fabric, optionally connects curve
points 112.
[0179] In some embodiments of the invention, wire 102 is formed
into its closed shape using two crimped tubes 122 which connect the
ends of wire 102 together at two different points, defining an
overlap portion 120 between the ends of wire 102. The use of two
crimped tubes 122 adds to the stability of the device and locks
against torque. Optionally, crimped tubes 122 are attached at
middle points along the length of a petal 104A. Alternatively or
additionally, crimped tubes 122 may be connected closer to the base
or closer to the tip 118 of the petal 104A. Further alternatively
or additionally, other devices may be added to device 100 to
increase its stability and/or a simple attachment at the distal end
of the petal is used, as described below with reference to FIG. 2B.
Overlap portion 120 may optionally also be used to define and/or
determine a preferred angle and/or position of device 100. Instead
of crimp tubes 122, other methods and/or devices may be used, such
as soldering, welding and/or glue bonding. Tubes 122 may be made
from any suitable biocompatible material, such as nitinol, titanium
or stainless steel.
Exemplary Structure and Sizes
[0180] In some embodiments of the invention, as shown in FIG. 1,
petals 104A and petals 104B are arranged alternately around central
orifice 106, such that each petal 104A is neighbored by two petals
104B on opposite sides. A different arrangement of petals, in which
two petals on one side of the wall are not separated by petals on
the other side of the wall is described below with reference to
FIG. 12. Petals 104A and 104b are optionally adapted to the side of
the wall they are to engage according to their height.
Alternatively or additionally, petals 104A and 104B are adapted to
their intended side of the wall by being pre-bent differently as to
the configuration they are to have in the deployed state. Further
alternatively or additionally, petals 104A and 104B are adapted to
their intended side of the wall by being designed to be folded in a
specific direction in delivery.
[0181] As shown in FIG. 1, device 100 includes six petals. In some
embodiments of the invention, however, the device may have more
petals, so as to better define a circular border for central
orifice 106, as a circular shape is better compatible to the body
in some cases, for example in not having sharp edges. On the other
hand, fewer petals makes device 100 simpler, possibly allowing
easier delivery. Exemplary numbers of petals include between 4 to
20, although more, and possibly fewer may be used under some
circumstances. In some embodiments of the invention, the anchoring
device includes an even number of petals, optionally half of the
petals being intended for each side of the wall. It is noted,
however, that anchoring devices in accordance with embodiments of
the present invention may have odd numbers of petals, such as 5, 7
or 9 petals.
[0182] Petals 104 are optionally sufficiently long to stabilize on
a tissue wall (e.g., prevent slippage), while not being too long as
in general it is desired to minimize the material inserted into
body organs. In an exemplary embodiment of the invention, one or
more of petals 104 is longer than 3 mm, longer than 5 mm, or even
longer than 8 mm as measured from curve points 112 to their tips
radially farthest from the curve points. Possibly, however, petals
104 are shorter than 10 mm or even shorter than 6 mm.
[0183] In some embodiments of the invention, all of petals 104 have
a same shape, width and length. In other embodiments, however,
different petals have different lengths, widths and/or shapes (for
example as shown in FIG. 12). For example, petals 104A intended for
a first side of the wall (e.g., the right atrium) may be longer
than petals 104B for the other side of the wall (e.g., the left
atrium), for example due to different expected pressures. In
another exemplary embodiment, one of petals 104A may be made longer
or wider than the other petals 104A in order to define a desired
orientation of device 100. Further alternatively or additionally,
one or more of petals 104 may be made shorter in order to conform
to the geometry of the body organ in which device 100 is to be
implanted.
[0184] As shown, petals 104 have a relatively wide base close to
central orifice 106, which narrows toward their tips 118, possibly
substantially monotonously. In some embodiments, having a wide base
and narrower tip makes it easier to fold device 100 for delivery
and for removal, if necessary. Alternatively, as discussed
hereinbelow, petals 104 may have other shapes. For example, petals
104 may have a narrow base which monotonously expands, especially
in embodiments including a skirt 116 (FIG. 4A below), as the
expanding petals may prevent slippage of the skirt during delivery.
In another exemplary embodiment of the invention, petals 104 have a
constant width and/or have an expanded distal end.
[0185] Petals 104 are optionally biased to apply pressure toward
the wall on which they are placed, so that the wall is firmly
caught between petals 104A and 104B, which serve as a double
spring. In addition to making the petals firmly hold the wall, the
bias of petals 104 optionally tensions curve points 112 and thus
increases the radial force applied by curve points 112.
Alternatively, petals 104 are in a rest state against the wall, so
as not to press hard against the wall which may be damaged by too
much pressure. In some embodiments of the invention, petals may me
curved away of the wall at their distal tips 118 or may be curved
back to pressure the wall at tip 118. Possibly, petals 104 are
coated with a material adapted to encourage tissue growth around
device 100, such that device 100 is embedded in the wall, after a
while.
[0186] The extent to which petals 104 are biased, the distance in
the axial (Z direction) between petals 104A and 104B and possibly
other parameters of device 100, such as the thickness of wire 102,
the length of petals 104 and/or the number of petals, optionally
depend on characteristics of the tissue in which the device is to
be implanted. The characteristics of the tissue may include, for
example, one or more of the thickness of the wall in which the
device is to be deployed, the calcium content of the tissue, the
electrical properties of the tissue and an extent of scarring of
the tissue. In an exemplary embodiment of the invention, a
plurality of devices 100 which differ in their parameter values are
produced. The device actually used on a specific patient is
selected according to the characteristics of the patient. For
example, a device 100 with longer petals and/or a stronger bias of
the petals toward the tissue is optionally used for softer tissue
from which the device may slip.
[0187] The distance in the Z direction between petals 104A and 104B
is optionally selected according to the thickness of the wall on
which device 100 is implanted. In some embodiments of the
invention, the total thickness of device 100, when deployed, is
less than 3 millimeters, less than 2 millimeters or even less than
a single millimeter. Alternatively or additionally, upon
implantation on a wall, device 100 extends beyond the wall, on both
sides of the wall together, by less than 2 millimeters, 1
millimeter or even less than 0.6 millimeters. The thickness of
device 100 is optionally less than 3%, 1% or even less than 0.5% of
the largest diameter of the area defined by the tips of petals
104.
Materials and Production
[0188] Wire 102 optionally has a circular profile, which does not
have sharp edges. Alternatively, wire 102 may have any other
convenient profile, for example a rectangular or square cross
section. Wire 102 is optionally thin, having a thickness of less
than 1 millimeter, less than half a millimeter or even less than
0.3 millimeters, in order to minimize the amount of foreign
material in the patient's body and allow folding into a delivery
device. In some embodiments of the invention, wire 102 has a
thickness of more than 0.1 millimeters or even more than 0.25
millimeters, so that it has sufficient strength to resist tissue
pressures in anchoring to a tissue wall. Optionally, over its
entire length, wire 102 has a same thickness. Alternatively, the
cross-section shape and/or thickness of wire 102 may vary over its
length, for example to have additional strength at curve points
112. In some embodiments of the invention, the variable thickness
of wire 112 is achieved in an etching process and/or an
electro-polishing process.
[0189] In some embodiments of the invention, device 100 is produced
from a wire which is bent into the desired shape of device 100.
Alternatively, device 100 is produced from a sheet which is etched
or cut into the desired shape. This alternative may be considered
advantageous in embodiments in which it is desired to have
different stiffness of the wire of petals 104 in different
directions.
[0190] Wire 102 may comprise substantially any bio-compatible
material, such as nitinol, stainless steel or a flexible hard
polymer. Wire 102 optionally comprises an elastic springy material,
for example a super-elastic material.
[0191] Nitinol has several advantages for use in anchoring device
100. Its super-elasticity allows anchor device 100 to be collapsed
for delivery into a small diameter and nitinol is considered highly
bio-compatible.
[0192] Possibly, the outer surface or wire 102 is relatively
smooth. Alternatively, the outer surface of wire 102 is roughened,
for example, in order to induce growth of tissue cells thereon and
thus cause wire 102 to be embedded partially or entirely in the
wall. The roughening is optionally performed using any suitable
method known in the art, such as applying micronic layers of a
porous polymer such as polyurethane by, for example,
electrospinning, applying fractal (e.g., ceramic) coatings such as
Titanium Nitride (TiN) or Iridium Oxide (Irox) and/or applying
other coatings which are used to increase capacitance of
electrodes.
[0193] Alternatively or additionally, wire 102 is coated with one
or more materials that encourage tissue growth and/or with other
materials, such as anti-inflammation (e.g., steroids) and/or other
drugs, such as a heparin-emitting polymer. The coating or
roughening may be added over the entire wire 102 or may be added
only on parts thereof. In an exemplary embodiment of the invention,
only the petals 104 to be located on one side of the wall, e.g.,
intended to be located in the left atrium are coated. Alternatively
or additionally, only the distal ends of the petals are coated,
leaving the proximal ends of the petals without tissue growth, such
that the orifice 106 is not blocked by tissue growth.
[0194] The portions coated are optionally selected in a manner
which minimizes inflammation and/or adverse reaction of the body to
device 100. In some embodiments of the invention, the portions
coated are selected in a manner which is directed to achieve a
desired size of orifice 106 and/or length of flow through orifice
106.
[0195] In some embodiments of the invention, metallic components of
device 100, such as wire 102 and/or skirt 116, undergo processes
such as electro-polish and/or passivation, on some or all of the
surfaces in order to prevent chemical contamination and/or to
prevent exposed surfaces from reacting with the environment.
Alternatively or additionally, wire 102 is encased in a thin ePTFE
(expanded polytetrafluoroethylene) cover, in order to improve the
hemocompatibility of the wire without substantially changing its
mechanical characteristics.
[0196] Device 100 optionally minimizes the amount of foreign
material participating in defining an orifice in a patient and
coming in contact with the blood stream passing through the
orifice. In some embodiments of the invention, less than 20%, less
than 15% or even less than 10% of the perimeter of the orifice is
covered by parts of device 100. For example, an opening of 5
millimeters in diameter has a circumference of about 15
millimeters. If wire 102 has a thickness of 0.3 millimeters and
crosses orifice 106 at six curve points 112, the total perimeter
area covered by wire 102 is 1.8 mm, which is 12% of a 15 millimeter
perimeter.
[0197] In some embodiments of the invention, device 100 does not
include pins or spikes which penetrate body tissue, thus being less
traumatic to the tissue wall in which the device is implanted.
Alternatively, for example in order to provide a better coupling,
device 100 includes pins or spikes which penetrate the tissue
wall.
Additional Embodiments of Anchor Device
[0198] FIG. 2A is a schematic illustration of an implant device
200, in accordance with another exemplary embodiment of the
invention. Device 200 includes eight petals 154 (marked 154A and
154B), arranged intermittently around a central orifice 106, In
device 300, the distal ends of petals 154 include a head of
increased size 160, which better anchors the petals on the wall,
for such cases in which additional anchoring is required.
[0199] FIG. 2B is a schematic illustration of an implant device
220, in accordance with still another exemplary embodiment of the
invention. Device 220 includes four petals 154, such that on each
side of the wall there are only two petals. One of the petals has a
connection point 212, at which the ends of the wire forming the
device are connected.
[0200] FIG. 2C is a schematic illustration of an implant device
320, in accordance with still another exemplary embodiment of the
invention. Device 320 includes three petals 104A, for a first side
of a wall on which device 320 is mounted, and three thin bars 134
for an opposite side of the wall. In an exemplary embodiment of the
invention, device 320 is implanted in the septum, thin bars 134 are
located in the left atrium and petals 104A are located in the right
atrium. Thus, the amount of material in the left atrium is
minimized. In some embodiments of the invention, one or more of
bars 134 has a pin 136 along its length, for example at its distal
end, which pin is used to anchor the bar in the septum.
[0201] Device 320 includes, in some embodiments of the invention,
one or more drug reservoirs 322, for example mounted on one or more
of petals 104A. The reservoirs 322 optionally contain a drug, such
as a steroid, which is slowly released from the reservoir according
to a predetermined scheme and/or according to instructions from a
controller. Alternatively, the drug is contained in a coating of
the device.
[0202] FIG. 2D is a schematic view of an anchoring device 380, in
accordance with an exemplary embodiment of the invention. Anchoring
device 380 comprises a central ring 382, which defines a passage
and prevents tissue from entering and occluding the passage. A
plurality of petals 384 extend radially from ring 382. Some of the
petals extend from an upper side 390 of the ring 382, while others
extend from a bottom 392 of the ring, such that petals 384 can
engage a tissue wall, in which ring 382 is positioned, between
them. Optionally, unlike petals 104, petals 384 are curved along
their extent from ring 382 to their distal end, in a manner which
avoids harsh bends, which may cause breakage and in a manner which
increases the pressure of the distal ends of petals 382 against the
tissue wall. In some embodiments of the invention, some or all of
petals 384 define a respective loop 386 along their length, for
example at their distal end. Loop 386 is optionally used for
engagement of the petals during delivery. Device 380 is
particularly suitable for production by laser cutting or etching
out of a tube, although other methods of production may also be
used. Device 380 is considered particularly suited for embodiments
in which a tube is carried by the anchoring device, for example a
tube having a length of more than 3 or even 5 millimeters. Device
380 is sufficiently massive to carry such a tube and its being less
foldable is not a concern in view of the tube which it carries.
[0203] Optionally, as shown, ring 382 comprises a solid sheet, for
example of nitinol or a thermoplastic material. Alternatively, ring
382 comprises a net texture, in order to minimize its material
content and allow folding during delivery into the patient. Use of
a net texture may also serve in anchoring ring 382 to the tissue.
Ring 382 optionally has a minimal height, of less than 5
millimeters, less than 3 millimeters or even less than 1
millimeter, in order to minimize the extent of foreign material
within the patient and the length of contact between blood flow and
ring 382. Alternatively or additionally, ring 382 may be cut or
slit, forming an open ring or being formed of a plurality of
separate portions. In some embodiments of the invention, ring 382
is coated entirely or at specific areas of the ring, with a porous
layer which enhances tissue growth. Alternatively or additionally,
ring 382 defines an internal drug reservoir which gradually
releases a drug, for example an anti-inflammatory drug.
[0204] Other symmetric or non-symmetric arrangements may be used
for anchoring devices in accordance with embodiments of the
invention.
[0205] In the above embodiments, petals intended to be on opposite
sides of the tissue wall are not located directly on opposite each
other, in order to avoid excess pressure on specific points of the
wall. In other embodiments of the invention, petals are located
partially or entirely parallel each other on opposite sides of the
wall.
[0206] FIG. 2E is a schematic illustration of an anchoring device
420, in accordance with another exemplary embodiment of the
invention. Device 420 includes banana shaped petals 422 and 424. As
shown, the petals 422 and 424 have distal heads pointing clockwise,
from a view directed at the petals in font of the wall. Thus, while
the portions of the petals close to central orifice 106 are
substantially parallel to each other on opposite sides of the wall,
the heads of the petals are not parallel to each other. In some
embodiments of the invention, however, the tips of different petals
422 and 424 are parallel each other on opposite sides of the tissue
wall. Petals of other shapes, such as hoof shaped with a larger
distal portion than proximal portion, may be used.
[0207] As with the above described embodiments, the petals 422 may
be distributed evenly or unevenly around the central orifice 106.
In addition, there may be the same number of petals 422 as petals
424 or there may be different numbers of petals 422 and 424.
[0208] FIG. 3 is a schematic illustration of an implant device 300,
in accordance with another exemplary embodiment of the invention.
Device 300 includes two external rings 302 which are to be located
on opposite sides of the wall. A plurality of bands 304 connect
between the two rings 302 in a manner which pressures the tissue of
the wall to keep the orifice in the wall open. Device 300 is shown
with four bands 304, although fewer or more bands may be used.
Bands 304 may be formed from the same material as rings 302 or may
be formed separately from a metal or plastic. Alternatively, bands
304 my be formed of a fabric, such as Dacron, ePTFE or PolyUrethane
strips.
[0209] Alternatively or additionally to bands 304, rings 302 may be
connected partially or entirely by a sheet of fabric or a mesh.
[0210] In some embodiments of the invention, in addition to rings
302, an additional smaller ring 306, which fits into or adjacent
orifice 106, is included in device 300.
[0211] In some embodiments of the invention, rings 302 are
elliptical and the longer axis of one ring 302 is located in a rest
state of device 300, against the shorter axis of the second ring
302, This arrangement of rings 302 allows folding of rings 302, by
applying pressure along arrows 308, for fitting into a narrow
delivery tool, without disturbance between the rings.
Alternatively, rings 302 are circular or have any other suitable
shape.
[0212] FIGS. 1-3 illustrate various embodiments of flat anchoring
devices. Combinations and variations of these embodiments may also
be used in accordance with the present invention. Further
embodiments of anchoring devices are described below, for example
with reference to FIGS. 6A and 6B.
Keep Orifice Open
[0213] As mentioned above, the above described anchoring devices
may be used on their own to keep an orifice open in internal tissue
of humans or animals. For example, in some congestive heart failure
(CHF) patients it is considered advantageous to perforate a hole
between the right and left atria or between other inner chambers.
Implanting of one of the above described anchoring devices holds
the orifice open, with minimal intervention.
Valve
[0214] in some embodiments of the invention, device 100 carries a
valve, which regulates the flow through the open orifice.
[0215] FIG. 4A is a schematic illustration of a valve 180 formed of
an anchor device 100 carrying a flap 138, in accordance with an
exemplary embodiment of the invention. Flap 138 is mounted on an
elastic arm 135 connected to one of petals 104A of anchor device
100. Arm 135 is optionally pre-configured with a bent portion 146
serving as a hinge of flap 138. Arm 135 is adapted to allow flap
138 to shift between a closed state in which flap 138 is adjacent
central orifice 106 and an open state in which the flap is
distanced from the central orifice and allows flow through the
orifice.
[0216] In some embodiments of the invention, a skirt 116 is mounted
on anchor device 100 in a manner which protects the tissue wall
from recurring strikes of flap 138. A wire 149 is positioned above
flap 138 in a manner which prevents flap 138 from opening by more
than an allowed extent.
Skirt
[0217] Skirt 116 optionally has a ring shape which surrounds
orifice 106. Alternatively to a round skirt, a polygon shaped skirt
may be used, for example having a number of sides equal to the
number of petals 104 to which the skirt is to be connected. Use of
such a polygon shaped skirt is expected to provide a good
attachment of the skirt to device 100, when attached to all the
petals intended to be on its side of the wall. Thus, skirt 116 is
kept flat, which provides a better contact between skirt 116 and
the tissue wall. For example, for a device 100 having three petals
104 on each side of the wall, a triangular skirt may be used.
Alternatively, skirt 116 is attached in a manner which allows some
slack, such that the skirt may have a wavy form, which could be
better in some cases for achieving a desired tissue growth pattern.
In some embodiments of the invention, skirt 116 is sufficiently
wide and/or thick, optionally, at least 100 microns (e.g. 150
microns) thick, for example to prevent undesired tissue growth
thereon and/or to protect against force applied by flap 138.
Alternatively, skirt 116 may be thinner and/or be otherwise
configured such that the skirt does not protect from force applied
by the flap.
[0218] In an exemplary embodiment of the invention, skirt 116 is
produced by dipping and has a thickness, without wire 102, of
between about 180-300 microns (e.g., 200 microns). For implanting
in the septum, skirt 116 optionally has an outer diameter including
the central orifice 106 of at least 0.5 centimeters, 1 centimeter
or even at least 1.3 centimeters. Optionally, skirt 116 does not
extend up to central orifice 106, under an assumption that this may
prevent additional obstruction of orifice 106 due to the edges of
the skirt. In some embodiments of the invention, in accordance with
this option, the inner edges of skirt 116 are distanced from the
central orifice by at least 1 millimeter or even at least 2 or 3
millimeters. Alternatively, the inner edges of the skirt reach up
to central orifice 106. Further alternatively or additionally,
skirt 116 has soft and/or sharp edges to avoid tissue growth.
[0219] In embodiments in which device 100 is implanted in the wall
between the left and right atria, the skirt is optionally located
in the right atrium, which has lower pressures and is less
disturbed by such an implant. In other embodiments of the
invention, device 100 includes two skirts, for both sides of the
wall on which device 100 is mounted.
[0220] In an exemplary embodiment of the invention, skirt 116 is
produced from the same material as wire 102. In some embodiments of
the invention, skirt 116 and wire 102 are produced together as a
single piece, for example in an etching process from a single tube
or sheet. In the etching process, different elements are optionally
given different thickness. For example, petals 104 may be made
relatively thick, while skirt 116, arm 135 and/or flap 138 are made
thinner with the same or different thicknesses.
[0221] Alternatively, skirt 116 and/or flap 138 are produced in a
deposit process. For example, skirt 116 is optionally produced by
depositing a material on wire 102. In some embodiments of the
invention, skirt 116 is formed of nitinol, a suitable polymer or of
cloth (e.g., Dacron). Alternatively or additionally, skirt 116
comprises polyurethane (PU) and/or ePTFE. Skirt 116 and/or flap 138
may be produced using any method known in the art, including the
methods described in U.S. Pat. No. 7,018,408 to Bailey et al.,
issued Mar. 28, 2006 and US patent publication 2006/0116751 to
Bayle et al., the disclosures of which documents are incorporated
herein by reference.
[0222] In another embodiment of the invention, skirt 116 is
manufactured using a dipping and brushing technique. Optionally, a
first skirt layer is dipped on a designated shaped mandrel. After a
partial curing process, the petals 104 on the side of skirt 116 are
held against the partially cured surface and additional layers of
the polymer are applied by brushing to obtain full and smooth
embedding of the petals in the skirt.
[0223] In some embodiments of the invention, skirt 116 comprises
two layers formed of different materials, that are bonded together
using any of the methods known in the art. One layer intended to
face the wall is rough and/or is otherwise adapted to induce tissue
growth and the other layer is optionally smooth and/or
anti-thrombosis.
[0224] As shown, petals 104B are embedded within skirt 116. In
other embodiments of the invention, skirt 116 is mounted on petals
104A on the opposite side from petals 1048. In still other
embodiments of the invention, skirt 116 is located between petals
104A and 1048.
[0225] Any suitable method may be used to attach skirt 116 to
petals 104A. In some embodiments of the invention, an adhesive is
used to connect skirt 116 to wire 102. Optionally, micro pores are
drilled in skirt 116 at the expected connection points using a
laser, in order to increase the effectiveness of the adhesive. In
some embodiments of the invention, wire 102 is woven through skirt
116, which is made in these embodiments of a suitable material to
allow weaving therethrough (e.g., eFTFE). In another embodiment of
the invention in which skirt 116 is formed from two layers, the two
layers are attached to each other with petals 104A between them. In
other embodiments of the invention, skirt 116 is made of a metal
and is welded, crimped or soldered to petals 104A.
[0226] In some embodiments of the invention, skirt 116 is a
substantially solid flat surface. Alternatively, in order to
minimize the amount of material, skirt 116 partially or entirely
comprises a mesh.
[0227] While skirt 116 is described for use with flap 138, in other
embodiments of the invention an anchoring device not carrying a
valve carries skirt 116 to protect the tissue wall for other
reasons, for example to prevent or induce tissue growth. In other
embodiments of the invention, flap 138 is used without skirt 116,
for example when the anchoring device 380 of FIG. 2D is used. Ring
382 of device 380 optionally has sharp edges, in embodiments in
which flap 138 is mounted thereon, in order to prevent tissue
growth on the ring.
[0228] FIG. 48 is a schematic illustration of an anchor device 171,
in accordance with another exemplary embodiment of the invention.
In anchor device 171, rather than limiting the amount of material
in the anchoring device to a minimum, two large skirts 177 and 179
connected together at a circle 139 surrounding orifice 106, are
used. Skirts 177 and 179 are formed of a flexible material which
allows minimally invasive delivery. In some embodiments of the
invention, skirts 177 and 179 are reinforced by external rings 143
and optionally an internal ring at circle 139. Alternatively or
additionally, other reinforcement structures are used, for example
device 100 or any of the other anchoring devices described above.
Inner circle 139 optionally has a diameter of at least 3, 5 or even
at least 8 millimeters. In an exemplary embodiment of the
invention, inner circle 139 has a diameter of about 10 millimeters
and external rings 143 have a diameter of about 25 millimeters.
Other dimensions may also be used.
[0229] The use of the embodiment of FIG. 4B is particularly useful
when the wall in which the anchor device is embedded is weak and
requires extra protection. Optionally, the inner surfaces of skirts
177 and 179 which face each other are coated with a growth
enhancing coating which induces tissue growth and enhances the bond
of the implant to the wall.
Skirt and Flap Coating
[0230] As discussed above regarding wire 102, skirt 116 is
optionally coated on its surface intended to face the wall, with a
drug which has desired therapeutic characteristics, such as an
anti-inflammatory drug. Alternatively or additionally, skirt 116 is
made rough or from a highly porous material on its face intended to
be directed to the wall, in order to encourage tissue growth and/or
better attach to the wall tissue.
[0231] In some embodiments of the invention, both skirt 116 and
wire 102 are treated using the same materials and/or application
techniques. Alternatively, wire 102 and/or areas of skirt 116 and
wire 102 which are subject to high friction and/or extensive
surface strain are treated with a porous polymer which endures such
strain and friction, while other areas, such as the flat areas of
skirt 106 are coated by a fractal coating.
[0232] The other face of skirt 116 is optionally made of a low
porous material, optionally sealed or otherwise smooth, to prevent
tissue growth thereon and/or adhesion of the flap to the skirt,
flap failure or formation of clots. Alternatively, the face of
skirt 116 not facing the wall is also coated to some extent, in
order to form at least a partial barrier between the skirt and
blood flow, in order to reduce coagulation. In some embodiments of
the invention, the coating on the face of skirt 116 not facing the
wall less induces tissue growth compared to the coating on the
other face.
[0233] In some embodiments of the invention, one or more surface of
skirt 116 is coated with an anti-inflammatory drug, like steroid to
prevent inflammation formation, which may encourage tissue growth.
Optionally, this layer is covered with blood diluting drugs, like
heparin, to prevent formation of clotting. The release of the drugs
may be immediate or slow for a short period of less than an hour,
or for a long period of more than an hour, several days, more than
two weeks or more.
[0234] Optionally, flap 138 is not coated to prevent tissue growth,
for example in those embodiments in which it is in movement.
Alternatively, for example in embodiments in which flap 138 only
moves under special conditions, flap 138 is partially or entirely
coated to prevent tissue growth. In some embodiments of the
invention, skirt 116, arm 135 and/or flap 138 are covered by a thin
ePTFE cover to improve their hemocompatibility.
[0235] In some embodiments of the invention in which a ring or
other portion of the anchoring device defines the orifice, as
illustrated in FIG. 2D, the ring may have a sharp edge in the
direction facing the flap 138, in order to prevent tissue growth on
the ring.
[0236] In some embodiments of the invention, flap 138 has a balloon
mounted on its surface facing orifice 106. Optionally, the balloon
is inflated before insertion into the patient. Alternatively, the
balloon is inflated using the delivery tool used in delivering the
flap into the patient. Further alternatively or additionally, the
balloon is inflated by an osmotic gradient method. The inflated
balloon may provide a better sealing of orifice 106 and/or cushion
the repeated forces of flap 138 against skirt 116 or the tissue
wall behind.
Flap and Arm
[0237] In some embodiments of the invention, the opening and
closing of flap 138 depend on the relative pressure between the
opposite sides of the wall on which valve 180 is mounted. The
pressure required in order to open flap 138 is optionally selected
according to the task of device 180 and is set, for example, by
controlling hinge 146 and/or the elasticity of arm 135.
Alternatively or additionally, the opening pressure of flap 138 is
controlled by selecting a desired size of the flap, a suitable
material from which the flap is manufactured, the length of arm 135
(i.e., a longer arm opens at lower pressure) and the width of the
arm. In some embodiments of the invention, the opening pressure of
valve 180 is set by setting the extent of preload of the flap 138,
e.g., the amount of force applied by the flap against anchor device
100 in its rest state.
[0238] In some embodiments of the invention, flap 138 comprises a
plastic or nitinol sheet cut into shape. The use of nitinol adds to
viewability by medical imaging modalities such as fluoroscopy. In
addition, nitinol has a high endurance to movements and can
withstand large reoccurrences of opening and closing of flap 138,
without suffering from substantial fatigue. Nitinol may also
facilitate a monolithic design, optionally made from a sheet of the
material.
[0239] It is noted, that other materials may also be used,
optionally with miniature radio opaque markers to allow visibility
in medical imaging methods. Such materials optionally have similar
properties as nitinol, although not necessarily the same.
[0240] Alternatively, flap 138 comprises a metal (e.g., nitinol)
frame, with a plastic or other material sheet held, optionally in
tension, by the frame. The plastic or other material sheet may be
rigid, flexible or elastic. In some embodiments of the invention,
flap 138 is formed from the same material as wire 102 optionally
being produced from a same sheet (e.g., foil), for example using an
etching procedure. The thickness of flap 138 is optionally selected
according to a desired stiffness of the flap. In some embodiments
of the invention, flap 138 has a thickness of less than 100
microns, less than 60 microns or even less than 40 microns (e.g.,
30 microns). Alternatively, flap 138 may have a thickness above 50
microns or even above 100 microns.
[0241] The length of arm 135 from the perimeter of flap 138 to a
maximal curvature point of hinge 146 is optionally at least 0.5
millimeters, at least 3 millimeters or even at least 5 millimeters.
In some embodiments of the invention, the length of arm 135 from
the perimeter of flap 138 to the maximal curvature point of hinge
146 is at least greater than half the diameter of flap 138 or is
even greater than the diameter of flap 138.
[0242] The maximal curvature point of hinge 146 is located, in some
embodiments of the invention, beyond the outer perimeter of anchor
device 100 in its flat deployed state. Optionally, in these
embodiments, the maximal curvature point of hinge 146 is at least
0.5 millimeters, at least 3 millimeters or even at least 5
millimeters beyond the outer perimeter of anchor device 100.
[0243] In some embodiments of the invention, flap 138 and arm 135
are formed as a single piece of the same material, for example
nitinol or a suitable polymer. Alternatively, flap 138 and arm 135
may be formed of separate pieces, possibly from different
materials.
[0244] Alternatively to being connected to an end of a petal 104A,
arm 135 may be connected to skirt 116. Further alternatively,
instead of mounting flap 138 on an elastic arm, flap 138 is mounted
on a pin hinge which rotates in a pin housing. Optionally, in
accordance with this alternative, a spring of any suitable type is
used to close the flap after it is opened.
[0245] In some embodiments of the invention, when the condition
governing the opening of flap 138 is met, it opens to a specific
extent, regardless of the pressure difference (i.e., pressure
gradient) between its opposite sides or the conditions that caused
it to open. Alternatively, the extent of opening of flap 138
depends on the pressure between the opposite sides of device 180.
In some embodiments of the invention, the extent of opening
increases linearly with the pressure, from a minimal pressure for
which flap 138 opens to a pressure corresponding to a maximal
opening extent of flap 138. Alternatively, the opening extent of
flap 138 is a non-linear function of the pressure on its opposite
sides. In some embodiments of the invention, a spiral spring is
connected to arm 135 to govern the opening of flap 138. The spiral
spring is optionally designed to allow opening to a small extent at
low pressure levels but requiring very high pressure, which
generally are never reached for large opening extents.
[0246] In the maximal opening extent of flap 138, the flap is
optionally at an angle of less than 30.degree., 20.degree., or even
less than 10.degree. relative to the surface containing petals 104.
Optionally, in the maximal opening extent, flap 138 is at an angle
of at least 5.degree. relative to the surface containing petals
104, for example 9.degree.. The strain on arm 135 optionally does
not exceed 0.5% or even does not exceed 0.3%, in order to avoid
wear due to fatigue.
[0247] Optionally, in its maximally open state, the projection of
flap 138 on central orifice 106 covers at least 50% or even at
least 75% of the orifice. In some embodiments of the invention, at
its maximal opening, the area of a surface between the tissue wall
and the flap is about equal to the area of central orifice 106,
allowing maximal flow. Accordingly, for example, the distance (H)
from the farthest edge of flap 138 to the tissue wall, in the open
state, is optionally substantially equal to a quarter of the
diameter of the orifice in the wall. Alternatively or additionally,
the maximal opening extent of flap 138 is selected to be small
enough such that it allows a substantially infinite number of
openings of the valve without causing arm 135 to break.
[0248] In some embodiments of the invention, in the maximal opening
state, the rate of flow of blood through central orifice 106 is
less than 2000 cc/min, less than 1500 cc/min or even less than 1000
cc/min in order to enable a sufficient amount of blood to go
through other paths even when flap 138 is purposely and/or
inadvertently maximally open. The blood flow rate through orifice
106 is optionally selected to achieve a required pressure drop
while maintaining a required cardiac output level.
[0249] In an exemplary embodiment of the invention, when device 180
is placed in the wall between the left atrium and the right atrium,
flap 138 is designed to open when the pressure gradient is above a
predetermined value, which is not encountered during a normal
cardiac cycle of a healthy patient. The opening is optionally
designed to pass a sufficient amount of blood from the left atrium
to the right atrium in order to alleviate high pressures associated
with CHF.
[0250] Alternatively, flap 138 is designed to open at lower
pressures, even pressures encountered during the normal cardiac
cycle of the patient. Optionally, in this alternative, the opening
at the lower pressure is for a short duration and/or to a small
extent, so that only a small amount of blood passes through the
orifice under normal conditions. The opening of flap 138 under
normal conditions is considered advantageous as it prevents
clotting, but does not have a substantial effect on the patient's
cardiac output and/or chambers loading or otherwise on the
patient's blood flow.
[0251] In some embodiments of the invention, flap 138 opens, when
the pressure in the left chamber is greater than in the right
chamber, even when there is only a small pressure gradient between
the sides of the wall. In other embodiments of the invention, flap
138 is preloaded, such that it only opens when the pressure
gradient is greater than zero, for example at least 1 mmHg, at
least 3 mmHg or even about 6 mmHg. In some embodiments of the
invention, flap 138 is preloaded to open only in response to high
pressures, for example pressures above 12 mmHg or even 15 mmHg.
Other pressure thresholds may be used according to the
characteristics of the specific patient in which device 180 is
implanted. In some embodiments of the invention, flap 138 is
produced preloaded with a predetermined pressure by pulling flap
138 below skirt 116 at the time of setting the rest state of flap
138.
[0252] The pressure gradient at which flap 138 opens to its maximal
extent, may be as low as 1 or 2 mmHg or lower, or may be higher,
for example at least 5 mmHg, at least 7 mmHg or even at least 10
mmHg. In an exemplary embodiment of the invention, flap 138 opens
to its maximal extent at a pressure gradient of about 12 mmHg.
[0253] In some embodiments of the invention, flap 138 has a slow
opening response time, such that flap 138 opens only when the
required opening pressure occurs for at least a minimal time, thus
avoiding opening due to sporadic short term pressure peaks or
pressure peaks occurring for short periods during the cardiac
cycle. Alternatively, flap 138 has a fast response time which is
faster than the heart pulse of the patient, for example less than
100 ms, or even less than 30 milliseconds, such that the valve will
open for short periods at frequent pressure spike occasions. In
accordance with this alternative, the frequent opening of flap 138
is considered advantageous in order to prevent clotting. In an
exemplary embodiment of the invention, flap 138 has a response rate
of about 30 Hz. Optionally, in these embodiments, flap 138 opens
frequently, e.g., every cardiac cycle, for a short period of less
than 100 milliseconds or even less than 60 milliseconds, for
example about 30 milliseconds. In some of these embodiments of the
invention, flap 138 is adapted to allow flow of between 400-600
cc/min, at times in which flap 138 is considered in a closed state,
i.e., the heart is not subject to high pressures and the flap only
opens for short periods. In some embodiments of the invention, flap
138 has a fast closing rate, e.g., less than 15 milliseconds, in
order to prevent back flow in the wrong direction. Flap 138
optionally has a very low mass and/or spring constant in order to
achieve the fast response time.
[0254] Optionally, when the pressures in the heart are normal, no
more than 1200 cc/min, no more than 800 cc/min, possibly no more
than 600 cc/min or even less than 400 cc/min is allowed to pass
through central orifice 106. In an exemplary embodiment of the
invention, about 600 cc/min is allowed to flow through central
orifice 106 under normal conditions. In other embodiments, smaller
amounts of blood are allowed to flow through the orifice under
normal conditions, for example between 200-300 cc/min.
[0255] Alternatively or additionally to setting the opening profile
of flap 138 to allow passage of a relatively small amount of blood
through orifice 106 under normal conditions, flap 138 is kept
slightly open by, for example, having an orifice or slit in flap
138 and/or by having flap 138 not close completely against orifice
106.
[0256] FIG. 4C is a graph which shows the correlation between the
pressure on flap 138 and the amount of blood shunting through
orifice 106, in accordance with various exemplary embodiments of
the invention. A first line 460 shows the flow through orifice 106
when flap 138 is fixed in a substantially closed state in which it
leaves only a small opening for blood flow. This may be achieved,
for example, by having a stopper keep flap 138 always slightly open
or have a small window in flap 138, which allows continuous
shunting of blood even when flap 138 is closed. As can be seen, as
the pressure gradient (.DELTA.P) between the chambers on the
opposite sides of the wall in which anchor 100 increases, the flow
through the orifice moderately increases.
[0257] Line 462 represents the flow through orifice 106 when flap
138 is held maximally opened regardless of the pressure gradient
between the chambers on opposite sides of the wall.
[0258] In some embodiments of the invention, flap 138 is set to
open only when the pressure gradient .DELTA.P is greater than a
threshold value .DELTA.P.sub.th. Line 464 represents the blood flow
through orifice 106, in one of these embodiments, in which flap 138
entirely closes orifice 106 and line 465 represents the blood flow
in another of these embodiments, in which flap 138 does not
entirely prevent blood flow in its closed state.
[0259] The slopes of lines 464 and 465 are determined by the spring
rigidity of flap 138. When the spring constant is low, flap 138 is
easily opened and the lines have a steep slope. In some embodiments
of the invention, when it is desired to open flap 138 maximally
when the pressure on the flap is above threshold value
.DELTA.P.sub.th arm 135 has a very low spring constant. In
contrast, in some embodiments of the invention, a high spring
constant is used, which in the graph of FIG. 4C is represented by a
non-steep slope.
[0260] The structure of device 100 and flap 138 (FIG. 4A) mounted
thereon is optionally used to adjust the threshold value
.DELTA.P.sub.th, for example by setting the preload extent of flap
138 and/or by adding a spring which adds to the pressure required
in order to open flap 138. In addition, the structure of device 100
and flap 138 may be controlled in order to set a maximal opening
extent of flap 138, for example by adding a non linear spring,
e.g., a spiral spring, which makes the pressure required to exceed
a predetermined opening extent, very high.
[0261] In some embodiments of the invention, threshold value
.DELTA.P.sub.th is set sufficiently high in order that flap 138
opens only when pressure levels above those normally encountered in
healthy patients during the cardiac cycle are encountered.
Optionally, in accordance with these embodiments line 465 is used,
such that blood regularly shunts through orifice 106 and prevents
coagulation. Optionally, in accordance with these embodiments,
threshold value .DELTA.P.sub.th is set to above 8 mmHg or even
above 10 mmHg.
[0262] In other embodiments of the invention, threshold value
.DELTA.P.sub.th is set relatively low, such that flap 138 opens in
substantially every cardiac cycle. For example, under normal
conditions, the pressure during the cardiac cycle varies between
.DELTA.P.sub.1 and .DELTA.P.sub.2 allowing passage of blood at a
rate of between 300-600 milliliters per minute. When, however, the
patient suffers from left atrial excess blood pressure levels, the
pressure varies between .DELTA.P.sub.1 and .DELTA.P.sub.3 allowing
shunting of blood at a rate of between 800-1200 milliliters per
minute. Optionally, in accordance with these embodiments, threshold
value .DELTA.P.sub.th is set to below 7 mmHg or even below 6 or 5
mmHg.
[0263] In some embodiments of the invention, a physician treating a
CHF patient selects a valve with a desired threshold value
according to a state of the patient. Optionally, in a patient in
which there is an expectance of reoccurrence of high pressures even
after the pressures are reduced to a desired level, a valve with a
low pressure threshold, for example less than 7 mmHg is used, so
that the valve will open periodically even when the patient does
not suffer from high pressures. Alternatively, when it is desired
that the valve permanently close when the pressures go down, a
valve with a high pressure threshold (e.g., above 7 or even above 9
mmHg) is used.
[0264] In some embodiments of the invention, flap 138 has a fast
response time, which is much shorter than the cardiac cycle of
patients. For example, the response time of flap 138 is optionally
shorter than 100 milliseconds or is even shorter than 50
milliseconds. In accordance with these embodiments, threshold value
.DELTA.P.sub.th is selected such that the average pressure
difference in a healthy patient is below the threshold, but during
the cardiac cycle the pressure reaches above the threshold. Due to
the short response time, flap 138 opens during a partial portion of
the cardiac cycle and thus provides washout of orifice 106.
[0265] In other embodiments of the invention, flap 138 has a slow
response time of close to the length of a single cycle of the
cardiac cycle. In these embodiments, threshold value
.DELTA.P.sub.th is optionally selected to be above the average
pressure during the cardiac cycle of a normal patient, such that
the valve opens only when the patient suffers from a high pressure
difference. Optionally, in accordance with these embodiments, flap
138 is held constantly slightly open or has a small window, which
allows washout of the orifice 106. Optionally, in these
embodiments, constant leakage due to a small opening can be used to
assure proper washout of the orifice.
[0266] Alternatively, threshold value .DELTA.P.sub.th is set to be
slightly below the average pressure between the right and left
atrium in a healthy patient. Thus, flap 138 regularly opens during
the cardiac cycle in healthy patients, but only small amounts of
blood shunt through orifice 106 when the flap opens, because the
opening extent is small. When, however, the patient suffers from a
high pressure difference, flap 138 opens to a greater extent and
allows passage of large amounts of blood.
Restriction Wire
[0267] Wire 149 (FIG. 4A) is optionally connected between two
points on skirt 116. Alternatively or additionally, wire 149 may be
connected between two of petals 104B. Wire 149 optionally prevents
flap 138 from opening by more than an allowed extent, in order to
prevent too much blood from passing through orifice 106 and/or in
order to prevent stressing arm 135. Wire 149 optionally comprises
Kevlar, nitinol or any other suitable biocompatible material.
[0268] Alternatively or additionally to wire 149, a string 151
connects skirt 116 or a petal 104B to arm 135 in a manner which
restricts the maximal opening extent of flap 138.
[0269] Alternatively to a restriction wire, a restriction string,
sheet or tab may be used.
Another Flap Embodiment
[0270] FIG. 5 is a schematic illustration of a flap valve 440, in
accordance with another exemplary embodiment of the invention.
Valve 440 comprises three petals 442 for one side of the tissue
wall and three petals 444 for the other side of the wall. The
petals have a non-symmetric shape, and are arranged such that they
partially overlap on opposite sides of the wall, increasing the
pressure applied on the wall, A flap 448, shown as being formed
from a frame and internal sheet, is held by a pair of holders 446
which extend substantially perpendicular to orifice 106. A handle
449 is optionally used in delivery of valve 440 into the patient
and/or removal of valve 440 from within the patient.
[0271] Alternatively to holders 446 extending substantially
perpendicular to flap 448 at the point of their connection in the
closed state, holders 446 may be connected at a smaller angle,
optionally an angle of at least 30.degree., at least 45.degree. or
even at least 60.degree..
[0272] In other embodiments of the invention, a flap connects to
its arm or handle at an angle of less than 30.degree., less than
20.degree. or even less than 10.degree..
Other Valves
[0273] Although the single flap valve described above has many
advantages, the present invention is not limited to any specific
valve, and anchor device 100 as well as other embodiments of the
present invention may be used with other types of valves, such as a
duck valve, a bi-leaflet valve, a tri-leaflet valve and/or a
parachute shaped valve. For example, for a leaflet valve, a short
tube, with the valve therein, is optionally mounted on device 100
with the central axis of the short tube covering central orifice
106.
[0274] FIGS. 6A and 6B illustrate an anchoring device 600, carrying
a shunt 628, in accordance with an exemplary embodiment of the
invention. Anchoring device 600 includes a ring 610, which carries
shunt 628. A plurality of bent arms 620 and 622 which are adapted
to clamp between them a tissue wall. Optionally, arms 620 and/or
622 include loop elements 636 at their distal ends. Loop elements
636 provide an attachment mechanism for a delivery system, and also
allow for reattaching the arms to the delivery system during a
removal or other procedure, if necessary. Loop elements 636
optionally also increase the area enduring the force applied by the
arms to the wall tissue and may further help to anchor device 600
in place by incorporating scar tissue within the loop area and over
a greater surface area.
[0275] In some embodiments of the invention, a circumferential
connecting wire 634 connects to arms 620 forcing the arms 620 to
move together and thus prevent arms from falling to an opposite
side of the wall, as well as to prevent arm entanglement and/or
unintentional premature release of one or multiple arms, in release
of anchoring device 600. Alternatively or additionally, wire 634
provides structural stability to the distal portion of device 600.
For example, wire 634 optionally prevents one or more of arms 620
from applying excess force against the tissue wall and if necessary
prevents one of the arms from migrating through the wall, to the
other side of the wall. Optionally, wire 634 may be used to
collapse arms 620 back into their folded state, for example if a
release of the arms was not successful and it is desired to perform
the release a second time.
[0276] Wire 634 is optionally formed from an elastic material, such
as nitinol or a polymeric material.
[0277] Alternatively to including a single loop element 636 at its
distal end, some or all of arms 620 and/or 622 may include a
plurality (e.g., two) of loops at their distal end. Two loops may
be used for example to pass wire 634 through both the loops. Loops
636 may be of substantially any suitable size, optionally having an
outer diameter between 1-10 millimeters.
[0278] Further alternatively or additionally, some or all of arms
620 are connected to wire 634 using any other connection method,
for example, permanently connecting (e.g., welding) arms 620 to
wire 634. Wire 634 may be connected permanently to arms 620, or may
be connected releasably (e.g., using snaps and/or adhesion), for
example, allowing removal of wire 634 after device 600 is anchored
on the tissue wall.
[0279] The number of arms in device 600 is optionally in accordance
with any of the embodiments described above regarding petals 104 in
device 100. It is noted, however, that more arms may be required
than petals, due to the fact that the petals may be viewed as
double arms. FIG. 6A illustrates 12 arms, six arms on each side of
the device, but more or fewer arms may be used.
[0280] During delivery, device 600 is optionally led into the
patient held in the orientation shown in FIG. 6B, by channel 500
(FIG. 14C), a delivery tool, or any other mechanism. When properly
positioned, the device is gradually or at once released and device
600 assumes its natural state shown in FIG. 6A, engaging the tissue
wall. Optionally, in the collapsed state of FIG. 6B, device 600 and
shunt 628 can fit into a tube of a diameter of less than 24 French,
optionally even not more than 18 or 15 French.
[0281] In some embodiments of the invention, shunt 628 comprises a
same material as anchor device 600 on which it is mounted.
Possibly, anchor device 600 and shunt 628 are formed from a single
sheet or tube of material using cutting or etching.
[0282] While shunt 628 is described in conjunction with anchoring
device 600, it is to be understood that it may be mounted on, or
produced with, any of the other anchoring devices described
herein.
[0283] Shunt 628 optionally comprises a valve, which regulates the
flow of blood through the shunt. The valve of shunt 628 may operate
in accordance with any of the opening schemes described above
regarding flap 138 and/or any other opening schemes known in the
art. Substantially any type of valve known in the art may be used,
including both active and passive valves, for example, a disc
attached to a spring, or a leaf opening. Examples of valves and
operation patterns which may be used are described more fully in
U.S. Patent publication US 2002/0173742, filed Apr. 20, 2001, in
U.S. Provisional application 60/573,378, flied May 24, 2004, and in
U.S. Patent Publication US 2005/0148925, filed Jul. 7, 2005, the
disclosures of all of which are incorporated herein by reference in
their entireties.
[0284] FIGS. 7A-7C describe a valve 660, which is mounted on shunt
628, in accordance with an exemplary embodiment of the invention.
Valve 660 comprises a frame 662, which supports a shunt cover 664
mounted on the frame through a pair of springs 666 and 668. A
stopper 665 optionally prevents spring 666 from expanding toward
cover 664 and compressing spring 668. Absent pressure through shunt
628 onto cover 664, cover 664 entirely prevents flow of blood
through the shunt. Alternatively, cover 664 in the closed state
only allows passage of a small blood volume. When, however, the
pressure increases to above a first threshold, spring 668,
collapses, opening a small blood passage, as shown in FIG. 7B.
Optionally, when spring 668 is collapsed, blood at a rate of
between about 300-600 milliliters per minute can pass through shunt
628. Alternatively or additionally, the collapse of spring 668
moves cover 664 away from the edge of shunt 628 by less than 2
millimeters, less than 1 millimeter or even not more than 0.5
millimeters. If the pressure increases to above a second threshold,
higher than the first threshold, also spring 666 gives way, as
shown in FIG. 7C, allowing cover 664 to move farther from shunt 628
and allowing a much larger amount of blood to pass through the
shunt. Optionally, the collapse of spring 666 allows cover 664 to
move at least 3 millimeters, at least 5 millimeters or even at
least 7 millimeters away from the edge of shunt 628. In some
embodiments of the invention, the compressing of spring 666 allows
cover 664 to move between 9-12 millimeters away from the edge of
shunt 628.
[0285] In some embodiments of the invention, the force required to
compress spring 668 is selected to be lower than the peak pressure
during a normal cardiac cycle of the patient in which shunt 628 is
implanted, such that in substantially every cardiac cycle cover 664
opens and allows flow of a small amount of blood which is believed
to prevent blood clotting in shunt 628. Spring 666 is optionally
selected, on the other hand, to require a pressure above the
highest pressure normally appearing in the cardiac cycle, such that
spring 666 is compressed only at clinically high pressures, such as
occurring in CHF patients. Optionally, for each patient, a specific
shunt 628 is selected from a plurality of shunts having springs of
different force profiles, according to the patients specific
characteristics.
[0286] Alternatively to only two springs, valve 660 may include
three or even more springs, in order to implement a more complex
opening profile.
[0287] Frame 662 is shown as including four support members 669 but
may include more or fewer members or may be replaced by any other
structure, such as a net.
[0288] FIG. 8A is a schematic illustration of a valve 670, in
accordance with an exemplary embodiment of the invention. In valve
670, the coil springs 666 and 668 of valve 660 are replaced by one
or more thin springy elements 676 and a springy tube 675, which is
compressed at protruding portions 678 only under high pressures.
Thin springy elements 676 have a fraction of the thickness of
springy tube 675, for example between 0.3 to 0.5 of the thickness.
Springy tube 675 and thin springy elements 676 are optionally
comprised of Nitinol or another shape memory alloy. Thin springy
elements 676 are optionally bendable up to 90 degrees, and require
less force for bending than protruding portions 678 of springy tube
675. Under low pressures, springy elements 676 give way and allow
passage of a small amount of blood. Under high pressures, springy
tube 675 collapses and gives way for larger amounts of blood.
[0289] FIG. 8B is a schematic illustration of a shunt 700 in
accordance with another embodiment of the present invention. Shunt
700 includes a frame 702 and an inner membrane 714. Membrane 714 is
comprised of flexible material, such as Dacron. Frame 702 is open
at a proximal end 703 and a distal end 704, but membrane 714 can be
compressed and block flow of fluid through shunt 700. A first
spring mechanism including inner spring arms 712 and a second
spring mechanism including outer spring arms 710 hold membrane 714
in a closed position, and can be outwardly compressed, releasing
membrane 714, thereby providing an opening for the flow of fluid
therethrough. At small pressure differentials, inner spring awls
712 may be pushed outwardly until they hit outer spring arms 710.
At higher pressures, such as during a CHF event, inner and outer
spring arms 710 and 712 are pushed further outwardly, opening
membrane 714 further, to allow for a greater amount of blood to
pass through shunt 700.
[0290] FIG. 9 is a schematic illustration of a valve 930, in
accordance with an exemplary embodiment of the invention. Valve 930
is shown as being mounted on an anchor device similar to device 171
of FIG. 4B. In valve 930, skirts 931 and 932 are intended to
capture a tissue wall between them. A rim 933 connects the skirts
931 and 932 and defines a blood passage between them. A cover 935
(corresponding to flap 138) mounted on a compressible rod 936
serves as a flap which controllably blocks flow through rim 933.
Optionally, a plurality of members 937 connected to skirt 932,
support compressible rod 936. Valve 930 may have any of the opening
profiles discussed above regarding flap 138, including preload
embodiments in which the rest point of cover 935 is below skirt 932
and even possibly below skirt 931.
[0291] Alternatively or additionally to rod 936 being compressible,
members 937 provide elasticity allowing movement of cover 935.
Cover 935 is mounted in accordance with this alternative on a
plurality of members (or arms), optionally at least three arms.
[0292] It is noted that the valve arrangement of valve 930 does not
necessarily need to be mounted on continuous skirts 931 and 932,
but rather may be mounted on other anchors, such as anchor 100. In
some embodiments of the invention, anchor 100 is embedded within
skirts 931 and/or 932.
Closure Device
[0293] The above described anchor devices may also be used to carry
a closure device for sealing undesired orifices in internal tissue
walls of humans. For example, instead of flap 138 being mounted on
central orifice 106 in a manner which allows opening of the orifice
for flow, flap 138 may be mounted over central orifice 106
permanently or any other cover may be mounted on the anchoring
device to cover orifice 106. Similarly, the other embodiments of
anchor devices and valves described herein may be used with minimal
changes in construction of closure devices.
[0294] FIG. 10A is a schematic illustration of a closure device
726, in accordance with an exemplary embodiment of the invention.
Device 726 comprises an anchoring portion formed from petals 104A
and 104B and a closure portion 198, which seals an orifice defined
by petals 104. Closure portion 198 is optionally substantially
larger than the area of orifice 106, for example having an area at
least 10%, 20% or even at least 40% greater than orifice 106. Such
a large closure portion achieves a substantially immediate closure
of the hole upon deployment and there is no need to wait for tissue
growth to achieve the seal.
[0295] FIG. 10B is a schematic illustration of a closure device
273, in accordance with another exemplary embodiment of the
invention. Closure device 273 comprises a closure portion 198 and a
plurality of anchoring arms 271 adapted to engage tissue between
the arms 271 and closure portion 198. Alternatively, a lower
portion 281 of arms 271 may extend sufficiently long, such that
wall tissue is caught between the ends of arms 271.
[0296] In some embodiments of the invention, arms 271 extend beyond
the outer perimeter of closure portion 198. Alternatively, arms 271
are shorter. As shown, arms 271 are located relatively close to the
outer perimeter of closure portion 198. Alternatively, arms 271 may
be located in the center of closure portion 198, adjacent each
other.
[0297] While two arms are shown, closure device 273 may include
more arms, possibly at least four or even at least six arms. The
arms are optionally elastic, for example formed from a suitable
polymer or metal. In some embodiments of the invention, the arms
are pre-shaped in an open state which engages tissue and are
delivered in a folded state. Upon release, the arms engage the
tissue wall. Alternatively, the arms are bent by a delivery tool
into their engaging state.
[0298] Alternatively or additionally, closure device 273 may
include one or more pins 277 which engage tissue by penetration
therein.
[0299] In an exemplary embodiment of the invention, in treating an
aneurism, for example in the septum, an orifice is perforated in
the aneurism and a closure device is implanted in the orifice, to
strengthen the wall suffering from the aneurism.
[0300] The closure devices may be produced using any of the methods
discussed above regarding the skirt 116 and flap 138, for example
using nitinol, stainless steel and/or thermoplastic polymers. In
some embodiments of the invention, a closure device as in FIG. 10A
or FIG. 10B is produced as a monolithic unit from nitinol or a
polymer.
Gradual Closure
[0301] In some embodiments of the invention, valve 180 (FIG. 4A) is
used to achieve a gradual closure device. Flap 138 is set to
require a very large pressure in order to open, thus keeping it
permanently closed absent an additional opening force. A
bio-degradable stopper optionally holds flap 138 open, until it
dissolves. Alternatively or additionally, skirt 116 and/or other
surfaces of valve 180 are coated with a bio-degradable material,
which prevents tissue growth. Once the bio-degradable material
dissolves, tissue begins to grow on skirt 116 until the tissue
growth causes valve 180 to be permanently closed. In some
embodiments of the invention, beneath the bio-degradable material
skirt 116 has a tissue growth enhancing drug, in order to speed up
the tissue growth. Alternatively or additionally, the smoothness of
skirt 116 and/or other surfaces of valve 180 are selected according
to a desired closure time. Further alternatively or additionally,
closure device 726, closure device 273 or a variation thereof is
used with a mesh instead of closure portion 198. The density of the
mesh optionally determines the time between implant and achieving
the complete closure, possibly together with other parameters, such
as anti-coagulation drug administration.
[0302] The time during which the material keeping the flow path
open dissolves is optionally selected according to the needs of the
patient. In an exemplary embodiment of the invention, the time
passing until the flap permanently closes is at least a week or
even at least 2 or 3 weeks.
[0303] The bio-degradable material may include, for example PEG
(Poly Ethylene Glycol), although other materials may be used.
Cannula Carrier
[0304] FIG. 11 is a schematic illustration of using anchoring
device 100 to hold a cannula 570, in accordance with an exemplary
embodiment of the invention. Cannula 570 may be held, for example,
in the inter-atrial septum 310 for draining blood from the left
atrium to the arterial system, for example as part of a cardiac
assist device. Alternatively, device 100 may be used in holding
tubes in other locations, for example a tube leading from the left
atria to the right atria.
Valve with Controller
[0305] FIG. 12 is a schematic top view of an implantable flow
control device 280, in accordance with an exemplary embodiment of
the invention. Device 280 comprises three petals 154A adapted to be
located on one side of a wall and three petals 154B adapted to be
located on another side of the wall. FIG. 12 illustrates that
petals 154A and 1548 may be of different lengths and that each two
petals 154A may be separated by a plurality of petals 154B. In this
arrangement, points 174 between petals 154A and 154B serve to
prevent wall tissue from entering the central orifice, while
proximal points 172 between adjacent petals 154B do not serve in
preventing tissue from extending into the central orifice, since
the petals 154B on both their sides are on the same side of the
wall. While points 172 do not add to the functionality of device
180 upon implantation, they optionally add to the anchoring of the
device when tissue begins to cover device 180. FIG. 12 further
illustrates a flap 138 mounted on a hinge 147 which serves as a
valve, sensors 142 and 144, a motor 196 and a controller 192.
[0306] In some embodiments of the invention, the opening and
closing of flap 138 is controlled by a controller 192, which
controls the opening and closing according to predetermined
settings and/or according to readings of one or more sensors, for
example any of the sensors detailed hereinbelow. Controller 192
optionally controls the valve using any method known in the art,
such as using an electromagnet and/or a motor 196. The sensors may
be located adjacent device 180, or may be remote from the device.
In some embodiments of the invention, controller 192 allows a human
operator to provide override commands which open, close or
otherwise set the state of flap 138, without relation to the
predetermined schemes for opening and closing the flap. The
override commands may be provided, for example, through wires
leading along the patient to a surface port on or beneath the
patient's skin. Other methods of externally controlling flap 138
include magnetic and/or RF coupling. Operation energy may be
provided to controller 192 by an embedded battery and/or by an
external source. In some embodiments of the invention, an anchor
device is coupled to a pacemaker or ICD and shares with its power
source.
[0307] The control may be performed according to any of the schemes
known in the art and/or any of those described in US patent
publication 2002/0173742, filed Apr. 20, 2001 and/or PCT
publication WO 2005/074367, filed Feb. 3, 2005, the disclosures of
which patent documents are incorporated herein by reference. For
example, the opening of flap 138 may depend on the absolute
pressure in one or more of the chambers of the heart, on the
temperature in one or more chambers of the heart, on the patient's
blood pressure and/or on the patient's blood oxygen content. The
control may also depend on any of the parameters used by
pacemakers, for example in synchronized pacing.
[0308] In some embodiments of the invention, device 180 may include
a pump 194, which aids in passing blood through the central
orifice, for example under instructions from controller 192.
Possibly, pump 194 and/or motor 196 are used in the normal
operation of device 180, substantially every time flap 138 is
opened or opened to a large extent. Alternatively, pump 194 and/or
motor 196 operate responsive to sensors that identify that flap 138
did not sufficiently open. Further alternatively, pump 194 and/or
motor 196 are used substantially only to override the normal
operation of flap 138 according to external human instructions.
Alternatively to the override being performed by an internal device
(e.g., motor 196), possibly battery operated, the override is
performed by an external device, for example by magnetic external
control.
Sensors
[0309] Device 280 further illustrates the mounting of sensors 142
and 144 on the implanted device. As shown, a first sensor 142 is
mounted on petal 154A and is located on one side of the wall, while
a second sensor 144 is mounted on petal 154B, located on the other
side of the wall. Thus, readings from both of sensors 142 and 144
may be read and compared in order to determine the relative
conditions on opposite sides of the wall. In an exemplary
embodiment of the invention, sensors 142 and 144 comprise one or
more temperature sensors and the relative temperature is used to
determine the flow pattern of blood in the patient or any other
characteristic of the patient's state. Alternatively or
additionally, any other sensors may be used and more or fewer
sensors may be mounted on device 180. For example, the sensors may
include one or more pressure sensors, oxygen (O.sub.2) sensors, B
Natriuretic Peptide (BNP) sensors, a sensor of toxic components,
flow sensors and/or pH sensors.
[0310] In some embodiments of the invention, the readings of
sensors 142 and/or 144 are used by controller 192 or an external
controller, in directly determining when flap 138 is to be
opened/closed. Alternatively or additionally, controller 192 or any
other controller, monitors the health state of the patient using
readings of one or more internal and/or external sensors, and
accordingly sets the opening profile of flap 138 as a function of
the pressure difference. Optionally, when it is determined that the
patient has recovered entirely, or when otherwise advantageous,
controller 192 instructs the valve to remain closed permanently.
Possibly, when necessary, controller 192 changes the minimal or
maximal pressure required to open the valve. In an exemplary
embodiment of the invention, when the state of the patient
deteriorates, the amount of blood allowed to flow through the valve
in its "closed" state is decreased. In other embodiments,
controller 192 may respond in other ways to the patient
deterioration, according to the specific medical intervention
considered best for the patient.
[0311] Alternatively or additionally, the readings of the sensors
are transmitted to a monitoring station outside the patient's body,
using wire and/or wireless transmission methods, for example using
any of the methods in the above described patent publications US
patent publication 2002/0173742, filed Apr. 20, 2001 and/or PCT
publication WO 2005/074367, filed Feb. 3, 2005.
Exemplary Deployment Method
[0312] FIG. 13 is a flowchart of acts performed in implanting an
anchoring device (e.g., device 100) in a heart in a minimally
invasive procedure, in accordance with an exemplary embodiment of
the invention. Device 100 is optionally delivered to the heart on a
delivery device, through a peripheral vein or artery, such as the
femoral vein or the right or left jugular veins in animals, or the
right or left subcalvian in humans.
[0313] If not already existent, an orifice is optionally formed
(400) in a wall of the heart, at a required location. In an
exemplary embodiment of the invention, the orifice is created using
a transeptal puncture tool, for example one including a needle and
a dilator catheter. In some embodiments of the invention, the
orifice is gradually enlarged, for example with a series of
diameter increasing dilators and/or with a non-compliant balloon,
until it reaches the desired size for the anchoring device used.
The balloon may be provided on the delivery tool of the anchor or
on a different tool. Alternatively, when a self expanding device,
such as anchoring device 100, is used, gradual enlarging is not
required and the entire medical procedure is shorter. The orifice
may be formed in muscle but is preferably formed in a membrane
which is easier to perforate. While device 100 may be used to
expand the orifice in which it is implanted, in some embodiments of
the invention device 100 does not expand the orifice and the
expansion is performed using dilating methods known in the art.
[0314] Alternatively, the device is implanted in an existing
orifice, for example in place of an inoperative natural valve
and/or in an undesired orifice for example in order to close the
orifice or to monitor the flow therethrough.
[0315] In some embodiments of the invention, the orifice is created
in the patient immediately before the implantation of the anchor
device, for example less than six hours, two hours or even less
than 30 minutes before the implantation. Alternatively, the anchor
device is implanted in the patient more than a day, more than a
week or even more than a month after the orifice was created and/or
identified.
[0316] The device 100 is provided (402) in a folded state mounted
on a distal end of a delivery medical tool. The minimally invasive
tool is then inserted (404) into the patient and the device is
brought to the orifice into which it is to be implanted.
Optionally, the position of the device is accurately adjusted (406)
and/or the device is rotated, until the device is in place, within
an orifice in a wall, for example between two heart chambers. The
device is then released (408) from the delivery tool and optionally
self opens into its open state, such that some of the petals are on
one side of the wall and some are on the other side of the
wall.
[0317] In some embodiments of the invention, device 100 continues
to expand (410) in place with curve points 112 radially pushing
against the tissue of the wall and expanding the orifice. Thus, the
size of the orifice is radially increased, reducing the chances of
trauma from shear forces in forming the orifice. Possibly, the
formed orifice has a diameter of less than 4 millimeters, less than
3 millimeters or even less than 2 millimeters and the expansion of
the device increases its diameter by at least 20%, 40% or even at
least 60%. Alternatively or additionally to self expanding, the
anchoring device may be expanded by a balloon, possibly a balloon
delivered on the same delivery tool as the anchoring device or on a
different tool guided on a same guide wire as the delivery tool of
the anchor device. Further alternatively, any other method of
generating the orifice may be used.
[0318] The implanting of device 100 in the heart is optionally
performed while the area is imaged by a real time imaging modality,
such as Intracardiac Echo (ICE), Angio and/or Trans-esophageal
Echocardiogram (TEE). In some embodiments of the invention, crimp
bar 120 and/or any other marker (e.g., radio-opaque marker) is used
to aid in properly orienting and/or positioning device 100 in
place. Radio-opaque markers, when used, are optionally positioned
at extreme locations of the anchoring device, for example at the
most radially distal points and/or the most radially inner
points.
[0319] As described below, the medical delivery tool is optionally
designed such that the device may be moved back and forth as much
as required for accurately adjusting (406) the location of the
device. Possibly, once the device is released in place, it cannot
be easily removed.
Device Release
[0320] In some embodiments of the invention, the release of the
device is performed all at once, such that all of petals 104 open
from their folded state substantially concurrently. Alternatively,
the release is performed gradually, in a plurality of steps. In an
exemplary embodiment of the invention, petals 104 of a distal side
of the wall from the direction in which the delivery tool
approaches the orifice (referred to herein without loss of
generality as petals 104A) are released first, and thereafter the
petals 104B of the proximal side of the wall are released. In other
embodiments of the invention, each of the petals is held separately
and released separately, for example as described below with
reference to FIG. 17 and/or in U.S. provisional applications
60/761,192, titled "Delivery System for Flow Regulation Device",
filed Jan. 23, 2006 and 60/777,315, titled "Arm Configuration for
Flow Regulation Device", filed Feb. 28, 2006, the disclosures of
which documents are incorporated herein by reference. In an
exemplary embodiment of the invention, device 100 is folded
non-symmetrically, so that each petal is released separately.
[0321] Device 100 is optionally preset in the open state, such that
absent an external force it moves to and remains in the open state,
using spring loading, pre-shaping, heat shrinking or any other
method known in the art. Possibly, device 100 is elastically
packaged, such that petals 104 spread out on their own when
released from the delivery tool. Alternatively or additionally,
external forces are used to induce the spreading out of the petals,
for example an externally applied magnetic force. Further
alternatively or additionally, a force applied through a minimally
invasive tool, such as a catheter balloon, is used to expand device
100 to its open state.
Exemplary Delivery Mechanism
[0322] FIG. 14A is a schematic illustration of anchoring device 100
being mounted into a delivery tool 490, in accordance with an
exemplary embodiment of the present invention. Delivery tool 490
comprises an outer channel 500 (FIGS. 14C and 14D), a core 502 and
a rod 506, adapted to push and pull core 502 within outer channel
500. In FIG. 14A, device 100 is partially inserted into a proximal
side of a magazine 509 in a folded shape having a small diameter
convenient for leading into the patient in a minimally invasive
tool. Optionally, magazine 509 has a size of less than 18 French,
less than 15 French or even less than 12 French. Petals 104B are
inserted distally into magazine 509, as petals 104B are intended to
be located on a distal side of the wall on which device 100 is
mounted. In an exemplary embodiment of the invention, the distal
side of the wall comprises the left atrium which is to receive as
little as possible foreign materials. Alternatively or
additionally, the side of the wall considered as the distal side is
selected according to the direction in which delivery tool 490 is
brought to the vicinity of the wall.
[0323] In some embodiments of the invention, core 502 comprises a
stiff material sufficiently hard to engage petals 104, but not too
hard so as not to damage delicate surfaces with which it may come
in contact, such as ceramic and/or oxidized surfaces of skirt 116,
arm 135 or flap 138 (FIG. 4A). Optionally, the material of core 502
has low friction with channel 500, and is suitable for acute
contact with tissue. In an exemplary embodiment of the invention,
core 502 comprises Delrin, Teflon, Nylon, Pebax and/or any other
suitable plastic. Alternatively, core 502 is formed of a metal or
alloy.
[0324] FIG. 14B is a schematic illustration of anchoring device 100
within magazine 509, in accordance with an exemplary embodiment of
the present invention. Core 502 comprises a plurality of
protrusions 504, optionally a protrusion for each petal 104A.
Petals 104A are placed in magazine 509 in a manner such that they
are caught between protrusions 504 and magazine 509, protrusions
504 allow device 100 to be pulled proximally within magazine 509
and channel 500, by pulling rod 506 proximally. Core 502 further
optionally comprises a shelf 508 which pushes device 100 distally
within magazine 509 and channel 500, when rod 506 is pushed
distally. In some embodiments of the invention, as shown in FIG.
14B, there is a short extent of axial freedom between pulling and
pushing device 100 by core 502. Alternatively, core 502 firmly
catches device 100 substantially without any axial freedom.
[0325] It is noted that device 100 may be provided from a
manufacturer already mounted within magazine 509 or may be mounted
by a physician or a medical staff member before the implantation
procedure. For example, immediately before (e.g., on the same day,
less than an hour before) the implantation procedure, the state of
the patient may be determined and accordingly a specific device 100
to be used may be selected and mounted in magazine 509,
[0326] FIG. 14C is a schematic illustration of the transfer of
anchor device 100 from magazine 509 to channel 500, in accordance
with an exemplary embodiment of the invention. The inner diameter
of magazine 500 is optionally designed to be substantially equal to
the inner diameter of channel 500. Magazine 500 with anchor device
100 folded within it is inserted into a haemostatic valve 517 of
delivery tool 490 (FIG. 14A). Rod 506 is then pushed forward to
move anchor device 100 out of magazine 509 into channel 500. Thus,
the inner diameter of channel 500 does not need to be large enough
to receive magazine 509 and there is more room for folded anchor
device 100 and/or channel 500 can have a smaller outer
diameter.
[0327] FIG. 14D is a schematic illustration of anchoring device 100
within delivery tool 490 in the vicinity of a wall 310, in
accordance with an exemplary embodiment of the present
invention.
[0328] Optionally, channel 500 is inserted into the patient using
any method known in the art and then rod 506 is pushed through
channel 500 and brought adjacent an orifice 312 in a wall 310.
[0329] After the distal end of channel 500 is passed through
orifice 312, rod 506 is carefully pushed distally for a small
extent, sufficient to release petals 104B from the distal end of
channel 500, but not to an extent which will allow petals 104A to
escape channel 500. Petals 104B optionally elastically expand to
the flat open configuration, which prevents pulling device 100
proximally from wall 310. Channel 500 and rod 506 are optionally
pulled proximally together such that petals 104B rest against wall
310. Channel 500 is then pulled proximally, while rod 506 is held
stationary, so as to release petals 104A from the channel. Petals
104A optionally self expand, such that device 100 moves to the
expanded state shown in FIG. 1. Thereafter, channel 500 and rod 506
are removed from the patient and the implant procedure is
complete.
[0330] In some embodiments of the invention, even after petals 140B
are released, rod 506 can be pulled proximally so as to pull petals
104B back into channel 500.
[0331] In some embodiments of the invention, during the insertion,
petals 104A and/or 104B and/or other portions of device 100 are
covered by a bio-degradable material, such as poly ethylene glycol,
which prevents the petals from tangling during the insertion
process. When device 100 is released from channel 500, the
bio-degradable material is dissolved and the petals open.
[0332] Optionally, if desired to release each petal separately,
protrusions 504 are located on core 504 at different axial levels
and each protrusion catches a different petal. In some embodiments
of the invention, one or more protrusions hold a plurality of
petals 104 together.
[0333] Although the above described method may be performed
manually by a physician carefully controlling rod 506 and channel
500 from their proximal ends, in some embodiments of the invention,
a proximal control handle is provided for control of the delivery
process, at the proximal end of channel 500, as is now described
with reference to FIGS. 15A-15C.
[0334] FIGS. 15A-15C are schematic illustrations of a handle 550 of
a minimally invasive delivery tool, in a process of implanting an
anchoring device, in accordance with an exemplary embodiment of the
invention. Handle 550 includes a proximal channel handle 520 which
is used to push and pull channel 500. A rod handle 530 is used to
move rod 506 backwards and forwards. In inserting delivery tool 490
(FIG. 14A) into the patient, both of handles 520 and 530 are
optionally used to push channel 500 and rod 506 together into the
patient. In order to release petals 104B from channel 500 (FIG.
14C), handle 530 is pushed distally into a niche 534 within handle
520, which only allows advancement of handle 530 with rod 506 to an
extent, shown in FIG. 15B, which allows release of petals 104B and
not petals 104A. Thereafter, handles 520 and 530 are pulled
proximally together to bring expanded petals 104B against wall 310.
Optionally, handles 520 and 530 may be rotated together, to bring
device 100 to a desired orientation. At this point, it is required
to pull channel 500 proximally relative to rod 506, in order to
release petals 104A. In an exemplary embodiment of the invention,
this is achieved, by first opening a safety lock handle 538, which
allows movement of a back handle 540, relative to handle 530. Back
handle 540 is optionally held stationary, while handles 520 and 530
are pulled proximally, so as to pull channel 500 proximally
relative to rod 506 and release petals 504A. In some embodiments of
the invention, the relative movement of handle 530 relative to back
handle 540 is damped by a spring 542 which prevents undesired rough
movements which may pull petals 104B out of place.
[0335] In some embodiments of the invention, rod 506 is not hollow.
Alternatively, a hollow channel passes within rod 506, which may be
used for passing fluids into and/or out of the patient. For
example, a channel within rod 506 may be used for rinsing and/or
applying suction to remove air bubbles. In some embodiments of the
invention, a channel through rod 506 may be used for passing tools,
e.g., a wire, to the vicinity of anchoring device 100. Optionally,
core 502 also has a channel defined through it, serving as a
continuation of the channel passing through rod 506. In some
embodiments of the invention, rod 506 comprises a catheter.
[0336] It is noted that the details of the delivery tool may be
varied and other types of delivery tools may be used. For example,
while in FIGS. 14A-14C each petal 104 is held by a separate
protrusion 504, in some embodiments of the invention fewer
protrusions may be used, although less controlling the delivery
process.
Delivery of Additional Elements
[0337] Optionally, in embodiments in which device 100 carries
additional elements, such as skirt 116, flap 138 and crimped tube
120, these elements are mounted on proximal petals 104A, such that
they are delivered on the proximal side of the wall 310.
Optionally, skirt 116 is folded into channel 500 between petals
104A, such that the petals 104A catch skirt 116 between them.
Alternatively, the skirt is folded around the petals, from the
outside. Further alternatively or additionally, any other delivery
methods may be used, for example any of the methods described in
above mentioned PCT publication WO 2005/027752.
[0338] FIG. 16 is a schematic view of a distal end of delivery tool
490, in accordance with another exemplary embodiment of the present
invention. In FIG. 16, delivery tool 490 is used to deliver an
anchoring device 100 together with flap 138 and arm 135 (FIG. 4A).
In FIG. 16, delivery tool 490 includes in addition to channel 500
and rod 506, a slotted tube 505 which is partially cut out toward
its distal end. Flap 138 and arm 135 are held between tube 505 and
rod 506 spread out on the rod. The use of tube 505 protects channel
500 from sharp edges of flap 138, for example when it is formed
from nitinol.
[0339] The cut out portion 507 of tube 505 optionally spans over
less than the width of flap 138, possibly even less than the width
of arm 135, such that the edges of the flap (and arm 135) come in
contact with tube 505 rather than with channel 500. In some
embodiments of the invention, cut out portion 507 spans over at
least 40.degree., 60.degree. or even at least 90.degree. of the
perimeter of rod 506. In an exemplary embodiment of the invention,
rod 506 has a diameter of between about 8-12 French, although
smaller or larger sizes may be used. Channel 500 optionally
comprises a soft material which is simple to produce, use and move
against body tissue, but is easily cut by sharp edges. For example,
channel 500 may comprise PTEE, PEBAX or other polymer materials.
Tube 505 optionally comprises a more durable material than channel
500. Alternatively, tube 505 is formed from the same material as
channel 500, possibly being thicker.
[0340] While tube 505 is within channel 500, flap unit 189 is held
in its flat state, as shown in FIG. 16, and optionally does not
substantially come in contact with channel 500. When cut out
portion 507 of tube 505 is pushed distally out of channel 500, or
when channel 500 is retracted, flap unit 189 is allowed to exit
through cut out portion 507. In some embodiments of the invention,
flap unit 189 is adapted to bend in a manner in which it narrows
and exits through cut out portion 507. Alternatively or
additionally, tube 505 comprises a soft, flexible and/or elastic
material, although preferably not as soft as channel 500, and flap
unit 189 is designed to apply pressure against tube 505. Cut out
portion 507 optionally expands under the pressure and allows flap
unit 189 to move radially out of tube 505, perpendicular to, and
away from, rod 506. Once released, flap unit 189 optionally sets
into its predetermined state in which it is employed. Using a soft
material for tube 505 additionally allows flap 138 to slightly dig
or cut into tube 505 and thus stabilizing flap unit 189 while it is
delivered within channel 500.
[0341] Alternatively to tube 505 allowing flap 138 and arm 135 to
exit once it is pushed out of channel 500, other triggers may be
required to cause tube 505 to allow flap 138 to be released. For
example, tube 505 may be made from a stiff material which softens
when cooled or heated. When it is desired to release flap 138, the
tube 505 is heated or cooled in order to release the flap unit.
Alternatively or additionally, a biodegradable material is used to
hold tube 505 in a state which prevents release of flap 138.
[0342] Alternatively to delivering flap 138 and arm 135 spread out
flat, valve 180 is delivered in a folded state similar to that
shown in FIG. 4A. Optionally, flap 138 is rolled into a rod which
is a continuation of arm 135 and petals 104 with skirt 116 are
folded over the rolled up flap. In this state, device 180 is
inserted into a delivery tool for delivery to an internal organ of
the patient. In a variation of this embodiment, rather than being
folded at the maximal curvature point of hinge 146, during
delivery, arm 135 is folded during delivery at a point closer to
flap 138, to prevent the flap for passing through the orifice and
getting stuck therein.
Additional Delivery Embodiments
[0343] In the embodiment described above with reference to FIG.
14C, all of the petals 104A on one side of the wall are released
together. While this is preferred for some anchoring devices, other
devices may have a risk of petal (or arm) entanglement when
allowing all the petals to be released together.
[0344] FIG. 17 is a schematic illustration of a delivery tool 750
of anchoring device 600 (FIGS. 6A and 6B), in accordance with an
exemplary embodiment of the invention. Delivery tool 750 comprises
an outer channel 500 and an inner rod 506 with a curled wire 752 in
the shape of a coil at its distal end. A handle 754 is used to move
channel 500 relative to inner rod 506 and/or to entirely move
delivery tool 750 into the patient. In use, anchoring device 600,
with shunt 628 mounted on it, is mounted in its folded state within
channel 500. Proximal arms 622 are mounted on curled wire 752,
curled wire 752 passing through loops 636.
[0345] When anchoring device 600 is properly positioned in an
orifice in which it is to be deployed, channel 500 is retracted
allowing arms 620 to expand. Thereafter, rod 506 is rotated in a
manner which releases arms 622 from curled wire 752. The rotation
is optionally performed slowly and/or in steps, allowing a
physician to carefully determine that a released arm 622 is
properly positioned, before releasing another awl 622. When all of
arms 622 have been released, rod 506 and channel 500 are removed
together from the patient.
[0346] Rod 506 is optionally sufficiently stiff to allow proximal
and distal movement relative to channel 500. Alternatively, rod 506
is only used for proximal movement relative to channel 500. On the
other hand, rod 506 is optionally sufficiently flexible to allow
its insertion percutaneously into inner organs of patients, such as
the heart.
[0347] Curled wire 752 is optionally formed of a strong material,
such as nitinol, stainless steel or titanium, which does not deform
and change its shape under the pressure of arms 622
[0348] In some embodiments of the invention, all of arms 622 are of
the same length. Alternatively, the arms have different lengths,
according to their locations on curled wire 752. It is noted that
other arrangements for gradually releasing arms 622 may be used in
accordance with embodiments of the invention. For example, arms 622
may have different lengths such that gradual retraction of channel
500 causes separate release of the arms.
[0349] Any of the delivery tools used for the anchoring devices may
include in addition to the elements required for the delivery,
other tools and/or elements such as working channels, a protective
sheath, one or more cameras and/or sensors. Thus, in addition to
performing the delivery, the delivery tool may be used to diagnose
the patient before or after the implant. For example, immediately
before the anchoring device is released, a last minute diagnosis,
for example by sensing pressure, blood flow and/or temperature may
be performed to by the same delivery tool to determine that the
implant procedure is safe. Alternatively or additionally, after the
anchoring device is implanted, sensors on the delivery device
determine whether there were problems in the implant and if
problems were encountered, the anchoring device may be removed, for
example as is now described with reference to FIG. 18. In some
embodiments of the invention, when a closure device is implanted, a
sensor on the delivery tool may determine whether the orifice
sufficiently sealed the orifice.
[0350] FIG. 18 is a schematic illustration of an anchor device 100
with a retrieval string 801, in accordance with an exemplary
embodiment of the invention. A retrieval string 801 connects distal
points 118 of petals 104A to a central junction 802. If necessary,
a hook 810 is passed through a working channel of the delivery
device, or is otherwise brought to central junction 802 and is
pulled proximally so as to fold petals 104A and pull them back into
channel 500. In some embodiments of the invention, in order to
insert hook 810, rod 506 is removed from channel 500. Thereafter,
channel 500 is advanced to push also distal petals 104B into
channel 500 and remove anchor device 100 from the patient.
[0351] Alternatively or additionally, petals 104 are long enough to
allow attachment of a patch to them from inside the heart, e.g.,
the right chamber, to aid in the removal.
[0352] Optionally, in embodiments in which an anchoring device
carries a closure portion 198, retrieval string 801 is connected to
closure portion 198. Optionally, in embodiments including flap 138,
a same string is used for restricting movements of the flap (wire
149, FIG. 4A) and for retrieval.
[0353] In some embodiments of the invention, petals 104A are
inclined toward central junction 802 in order to allow easier
collapse.
[0354] Although anchor device 100 is described herein as being
suitable for insertion in minimally invasive procedures, the anchor
devices of the present invention may also be delivered in open
surgery and in some embodiments of the invention, anchor devices
not suitable for minimally invasive surgery are used.
CONCLUSION
[0355] It will be appreciated that the above-described methods may
be varied in many ways, including, changing materials, sizes and
shapes. For example, rather than folding device 100 in an organized
manner, device 100 may be packaged by an irregular folding and/or
by a collapsing of the device without any preplanned folding
scheme. Furthermore, device 100 may have a structure which conforms
to a wavy or other shaped tissue wall surface.
[0356] It should also be appreciated that the above described
description of methods and apparatus are to be interpreted as
including apparatus for carrying out the methods, and methods of
using the apparatus.
[0357] The present invention has been described using non-limiting
detailed descriptions of embodiments thereof that are provided by
way of example and are not intended to limit the scope of the
invention. It should be understood that features and/or steps
described with respect to one embodiment may be used with other
embodiments and that not all embodiments of the invention have all
of the features and/or steps shown in a particular figure or
described with respect to one of the embodiments. Particularly, the
delivery tools described for one anchoring device may be used for
other anchoring devices. Also, the valves, closure devices and
tubes described as being mounted on a specific anchoring device may
be mounted on any of the other described anchoring devices and/or
combination or variations thereof.
[0358] Variations of embodiments described will occur to persons of
the art. Furthermore, the terms "comprise," "include," "have" and
their conjugates, shall mean, when used in the claims, "including
but not necessarily limited to".
[0359] It is noted that some of the above described embodiments may
describe the best mode contemplated by the inventors and therefore
may include structure, acts or details of structures and acts that
may not be essential to the invention and which are described as
examples. Structure and acts described herein are replaceable by
equivalents which perform the same function, even if the structure
or acts are different, as known in the art. Therefore, the scope of
the invention is limited only by the elements and limitations as
used in the claims.
* * * * *