U.S. patent application number 13/368685 was filed with the patent office on 2012-11-08 for atrial appendage occlusion and arrhythmia treatment.
Invention is credited to Randell L. Werneth, David Zarbatany.
Application Number | 20120283585 13/368685 |
Document ID | / |
Family ID | 46639172 |
Filed Date | 2012-11-08 |
United States Patent
Application |
20120283585 |
Kind Code |
A1 |
Werneth; Randell L. ; et
al. |
November 8, 2012 |
Atrial Appendage Occlusion and Arrhythmia Treatment
Abstract
Atrial appendage occlusion devices and arrhythmia treatment.
Inventors: |
Werneth; Randell L.; (San
Diego, CA) ; Zarbatany; David; (Laguna Niguel,
CA) |
Family ID: |
46639172 |
Appl. No.: |
13/368685 |
Filed: |
February 8, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61441627 |
Feb 10, 2011 |
|
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Current U.S.
Class: |
600/508 ;
606/200 |
Current CPC
Class: |
A61B 2017/00597
20130101; A61B 2017/00615 20130101; A61B 2017/00592 20130101; A61B
2017/00601 20130101; A61B 17/0057 20130101; A61N 1/3756 20130101;
A61B 2017/00243 20130101; A61P 9/06 20180101 |
Class at
Publication: |
600/508 ;
606/200 |
International
Class: |
A61B 5/02 20060101
A61B005/02; A61F 2/01 20060101 A61F002/01 |
Claims
1. An implantable cardiac orifice occlusion and arrhythmia
treatment device, comprising: an anchoring portion adapted to
anchor the device in place adjacent a cardiac orifice; a barrier
element secured to the anchoring portion and adapted to cover the
orifice when implanted, and adapted to prevent blood clots from
passing through the barrier element; and an arrhythmia treatment
element secured to at least one of the anchoring portion and the
barrier element, the treatment element adapted to treat a detected
cardiac arrhythmia.
2. The device of claim 1 further comprising an electrical activity
monitoring element adapted to monitor electrical activity of the
heart indicative of the arrhythmia.
3. The device of claim 2 where the monitoring element is adapted to
be disposed in contact with atrial tissue to monitor electrical
activity of the heart.
4. The device of claim 2 wherein the monitoring element is adapted
to be disposed in contact with atrial appendage tissue to monitor
electrical activity of the heart.
5. The device of claim 2 wherein the monitoring element comprises
an arrhythmia detection component adapted to detect when the
arrhythmia is occurring.
6. The device of claim 5 wherein the treatment element is adapted
to treat the arrhythmia when the arrhythmia is detected by the
detection component.
7. The device of claim 5 wherein the monitoring element comprises
an arrhythmia detection component adapted to detect when atrial
fibrillation is occurring.
8. The device of claim 2 wherein the anchoring portion, the barrier
element, the monitoring element, and the treatment element are
integrated into a singular implantable device.
9. The device of claim 2 further comprising a detector adapted to
detect when the arrhythmia is occurring, the detector is disposed
external to the patient, wherein the monitor is adapted to transmit
data indicative of the electrical activity of the heart to the
detector.
10. The device of claim 1 wherein the treatment element is adapted
to pace cardiac tissue to treat the detected arrhythmia.
11. The device of claim 1 wherein the treatment element is adapted
to deliver a therapeutic agent to cardiac tissue to treat the
detected arrhythmia.
12. The device of claim 1 wherein the anchoring portion, the
barrier element, and the treatment element are integrated into a
singular implantable device.
13. The device of claim 1 wherein the anchoring portion comprises a
distal deformable anchoring portion and a proximal deformable
anchoring portion, the distal anchoring portion adapted to be
deployed in a left atrial appendage and anchored to left atrial
appendage tissue, wherein the proximal anchoring portion is adapted
to be deployed in a left atrium and anchored to left atrial
tissue.
14. A method of cardiac orifice blocking and arrhythmia treatment,
comprising: an integrated implantable device comprising an
anchoring portion, a barrier element, a monitor, and a treatment
element; anchoring the anchoring portion against cardiac tissue
near a cardiac orifice to block the flow of clots through the
orifice with the barrier; positioning the monitor to be in contact
with cardiac tissue to monitor cardiac activity indicative of an
arrhythmia; and providing for the treatment of the arrhythmia with
the treatment element.
15. The method of claim 14 wherein the positioning step comprises
positioning the monitoring component against atrial tissue.
16. The method of claim 14 wherein the positioning step comprises
positioning the monitoring component against atrial appendage
tissue.
17. The method of claim 14 wherein the anchoring step comprises
allowing the anchoring portion to deform from a delivery
configuration towards a deployed configuration in which it anchors
against cardiac tissue.
18. A cardiac orifice blocking device, comprising: an anchoring
portion comprising a proximal anchoring portion and a distal
anchoring portion, the proximal anchoring portion adapted to be
anchored against left atrial tissue, and the distal anchoring
portion adapted to be anchored against left atrial appendage
tissue; a hub secured to the proximal and distal anchoring
portions; a barrier portion comprising a proximal barrier secured
to the proximal anchoring portion, the proximal barrier adapted to
prevent blood clots from passing therethrough, and a distal barrier
portion secured to the distal anchoring portion.
19. The device of claim 18 wherein the proximal anchoring portion
has a greater radial dimension in a deployed configuration that a
radial dimension of the distal anchoring portion in a deployed
configuration.
20. The device of claim 18 wherein the proximal anchoring portion
comprises a plurality of deformable anchoring elements that extend
substantially radially outward from the hub in their deployed
configurations.
21. The device of claim 18 wherein the proximal anchoring portion
comprises a plurality of deformable anchoring elements, each of the
plurality of anchoring elements having a loop configuration.
22. The device of claim 21, wherein the plurality of anchoring
elements are in the same plane in a side view of the device.
23. The device of claim 22 wherein the plane is substantially
orthogonal to a longitudinal axis of the hub.
24. The device of claim 20 wherein the distal anchoring portion
comprises a plurality of deformable anchoring elements that extend
substantially radially outward from the hub in their deployed
configurations.
25. The device of claim 18 wherein the distal anchoring portion
comprises a plurality of deformable anchoring elements, each of the
plurality of anchoring elements having a loop configuration.
26. The device of claim 25 wherein the plurality of anchoring
elements are in the same plane in a side view of the device.
27. The device of claim 26 wherein the plane is substantially
orthogonal to a longitudinal axis of the hub.
28. The device of claim 18 wherein the proximal barrier is secured
proximal to the proximal anchoring portion.
29. The device of claim 18 wherein the distal barrier is secured
proximal to the distal anchoring portion.
30. The device of claim 18 wherein the proximal barrier comprises
at least one pleat in the barrier material.
31. The device of claim 18 wherein the proximal barrier has a
substantially circular configuration.
32. The device of claim 18 wherein the distal barrier has a
substantially circular configuration.
33. The device of claim 18 wherein the proximal anchoring portion
comprises a plurality of deformable proximal anchoring elements
that extend substantially radially outward from the hub in their
deployed configurations, and the distal anchoring portion comprises
a plurality of deformable distal anchoring elements that extend
substantially radially outward from the hub in their deployed
configurations, wherein the proximal anchoring elements extend
further radially outward than the distal anchoring elements.
34. The device of claim 18 wherein the distal anchoring portion and
the proximal anchoring portion are formed integrally with the
hub.
35. The device of claim 18 wherein the proximal barrier has a
greater radial dimension than the distal barrier when the distal
and proximal anchoring portions are in their respective deployed
configurations.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent
Application No. 61/441,627, filed Feb. 10, 2011, the entire
disclosure of which is incorporated by reference herein.
INCORPORATION BY REFERENCE
[0002] All publications and patent applications mentioned in this
specification are herein incorporated by reference to the same
extent as if each individual publication or patent application was
specifically and individually indicated to be incorporated by
reference.
BACKGROUND OF THE DISCLOSURE
[0003] Atrial fibrillation ("AF") is an arrhythmia of the heart
that results in a rapid and chaotic heartbeat, producing lower
cardiac output and irregular and turbulent blood flow in the
vascular system. The left atrial appendage ("LAA") is a cavity
extending from the lateral wall of the left atrium between the
mitral valve and the root of the left pulmonary veins. The LAA
normally contracts with the rest of the left atrium during a normal
heart cycle, keeping blood from becoming stagnant therein, but
often fails to contract with any vigor in patients experiencing AF
due to the discoordinate electrical signals associated with AF. The
result is that blood tends to pool in the LAA, which can lead to
the formation of blood clots therein. The blood clots can then
propagate out from the LAA into the left atrium. Since blood from
the left atrium and ventricle supply the heart and brain, blood
clots from the LAA can obstruct blood flow thereto, causing heart
attacks, strokes, or other organ ischemia. Blood clots form in the
LAA in about 90% of patients with atrial thrombus. Patients with AF
account for one of every six stroke patients, and thromboemboli
originating from the LAA are the suspected culprit in the vast
majority of these cases. More than 3 million Americans have AF,
which increases their risk of stroke by a factor of 5. Elimination
or containment of thrombus formed within the LAA of patients with
AF will significantly reduce the incidence of stroke in those
patients.
[0004] Administering an anticoagulant such as warfarin is the most
commonly prescribed treatment for stroke prevention in patients
with AF. The effectiveness of warfarin, however, is challenged due
to serious side effects, lack of patient compliance in taking the
medication, a narrow therapeutic window, and an increased risk of
bleeding.
[0005] LAA occlusion can be used as an alternative for patients who
cannot use oral anticoagulants such as warfarin. Approximately 17%
of patients cannot take anticoagulants because of a recent or
previous bleeding, non-compliance, or pregnancy. Current US
FDA-approved occlusion methods staple the LAA closed or suture and
excise the appendage. Studies, however, have shown these techniques
produce inconsistent results. Some new approaches, currently under
FDA investigation, deliver an implant from within the vascular
system.
[0006] Devices are needed, however, to more consistently and
effectively prevent clots from entering the atrium from the
appendage. While blocking the appendage from the atrium can prevent
thrombus from entering the atrium, an approach that can also
provide therapy for the arrhythmia will reduce the risk of stroke
while treating the arrhythmia.
SUMMARY OF THE DISCLOSURE
[0007] One aspect of the disclosure is an implantable cardiac
orifice occlusion and arrhythmia treatment device, comprising: an
anchoring portion adapted to anchor the device in place adjacent a
cardiac orifice; a barrier element secured to the anchoring portion
and adapted to cover the orifice when implanted, and adapted to
prevent blood clots from passing through the barrier element; and
an arrhythmia treatment element secured to at least one of the
anchoring portion and the barrier element, the treatment element
adapted to treat a detected cardiac arrhythmia.
[0008] In some embodiment the device further includes an electrical
activity monitoring element adapted to monitor electrical activity
of the heart indicative of the arrhythmia. The monitoring element
can be adapted to be disposed in contact with atrial tissue to
monitor electrical activity of the heart. The monitoring element
can be adapted to be disposed in contact with atrial appendage
tissue to monitor electrical activity of the heart. The monitoring
element can include an arrhythmia detection component adapted to
detect when the arrhythmia is occurring. The treatment element can
be adapted to treat the arrhythmia when the arrhythmia is detected
by the detection component. The monitoring element can include an
arrhythmia detection component adapted to detect when atrial
fibrillation is occurring. The anchoring portion, the barrier
element, the monitoring element, and the treatment element can be
integrated into a singular implantable device. The device can also
include a detector adapted to detect when the arrhythmia is
occurring, the detector being disposed external to the patient,
wherein the monitor is adapted to transmit data indicative of the
electrical activity of the heart to the detector.
[0009] In some embodiments the treatment element is adapted to pace
cardiac tissue to treat the detected arrhythmia.
[0010] In some embodiments the treatment element is adapted to
deliver a therapeutic agent to cardiac tissue to treat the detected
arrhythmia.
[0011] In some embodiments the anchoring portion, the barrier
element, and the treatment element are integrated into a singular
implantable device.
[0012] In some embodiments the anchoring portion includes a distal
deformable anchoring portion and a proximal deformable anchoring
portion, the distal anchoring portion adapted to be deployed in a
left atrial appendage and anchored to left atrial appendage tissue,
wherein the proximal anchoring portion is adapted to be deployed in
a left atrium and anchored to left atrial tissue.
[0013] One aspect of the disclosure is a method of cardiac orifice
blocking and arrhythmia treatment, comprising: an integrated
implantable device comprising an anchoring portion, a barrier
element, a monitor, and a treatment element; anchoring the
anchoring portion against cardiac tissue near a cardiac orifice to
block the flow of clots through the orifice with the barrier;
positioning the monitor to be in contact with cardiac tissue to
monitor cardiac activity indicative of an arrhythmia; and providing
for the treatment of the arrhythmia with the treatment element.
[0014] In some embodiments the positioning step comprises
positioning the monitoring component against atrial tissue.
[0015] In some embodiments the positioning step comprises
positioning the monitoring component against atrial appendage
tissue.
[0016] In some embodiments the anchoring step comprises allowing
the anchoring portion to deform from a delivery configuration
towards a deployed configuration in which it anchors against
cardiac tissue.
[0017] One aspect of the disclosure is a cardiac orifice blocking
device, comprising: an anchoring portion comprising a proximal
anchoring portion and a distal anchoring portion, the proximal
anchoring portion adapted to be anchored against left atrial
tissue, and the distal anchoring portion adapted to be anchored
against left atrial appendage tissue; a hub secured to the proximal
and distal anchoring portions; a barrier portion comprising a
proximal barrier secured to the proximal anchoring portion, the
proximal barrier adapted to prevent blood clots from passing
therethrough, and a distal barrier portion secured to the distal
anchoring portion.
[0018] In some embodiments the proximal anchoring portion has a
greater radial dimension in a deployed configuration that a radial
dimension of the distal anchoring portion in a deployed
configuration.
[0019] In some embodiments the proximal anchoring portion comprises
a plurality of deformable anchoring elements that extend
substantially radially outward from the hub in their deployed
configurations.
[0020] In some embodiments the proximal anchoring portion comprises
a plurality of deformable anchoring elements, each of the plurality
of anchoring elements having a loop configuration. The plurality of
anchoring elements can be in the same plane in a side view of the
device, and it can be substantially orthogonal to a longitudinal
axis of the hub. The distal anchoring portion can include a
plurality of deformable anchoring elements that extend
substantially radially outward from the hub in their deployed
configurations. The distal anchoring portion can include a
plurality of deformable anchoring elements, each of the plurality
of anchoring elements having a loop configuration. The plurality of
anchoring elements can be in the same plane in a side view of the
device, which can be substantially orthogonal to a longitudinal
axis of the hub.
[0021] In some embodiments the proximal barrier is secured proximal
to the proximal anchoring portion.
[0022] In some embodiments the distal barrier is secured proximal
to the distal anchoring portion.
[0023] In some embodiments the proximal barrier comprises at least
one pleat in the barrier material.
[0024] In some embodiments the proximal barrier has a substantially
circular configuration.
[0025] In some embodiments the distal barrier has a substantially
circular configuration.
[0026] In some embodiments the proximal anchoring portion comprises
a plurality of deformable proximal anchoring elements that extend
substantially radially outward from the hub in their deployed
configurations, and the distal anchoring portion comprises a
plurality of deformable distal anchoring elements that extend
substantially radially outward from the hub in their deployed
configurations, wherein the proximal anchoring elements extend
further radially outward than the distal anchoring elements.
[0027] In some embodiments the distal anchoring portion and the
proximal anchoring portion are formed integrally with the hub.
[0028] In some embodiments the proximal barrier has a greater
radial dimension than the distal barrier when the distal and
proximal anchoring portions are in their respective deployed
configurations.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Exemplary patentable features of the disclosure are set
forth in the claims. A better understanding of the features and
advantages of the present disclosure will be obtained by reference
to the following detailed description that sets forth illustrative
embodiments, in which the principles of the disclosure are
utilized, and the accompanying drawings of which:
[0030] FIG. 1 illustrates an exemplary embodiment of a device
adapted to prevent clots from entering the left atrium from the
left atrial appendage.
[0031] FIG. 2 illustrates an exemplary embodiment of an implant
adapted to prevent clots from entering the left atrium from the
left atrial appendage.
[0032] FIG. 3 illustrates an exemplary embodiment of an implant to
prevent clots from entering the left atrium from the left atrial
appendage.
[0033] FIGS. 4A-4E illustrate an exemplary embodiment of an implant
adapted to prevent blood flow into the left atrial appendage.
[0034] FIG. 5 illustrates an exemplary embodiment of an occlusion
implant.
[0035] FIG. 6 illustrates a variation on the embodiment in FIG. 5
in which the device includes a barrier secured to an expandable
anchor.
[0036] FIGS. 7A-7C illustrate an exemplary embodiment in which one
or more of the anchors is made from a tubular element in which
portions of the tube are removed to creates slots therein.
[0037] FIGS. 8A and 8B illustrate an exemplary embodiment of an
implant that can occlude the left atrial appendage.
[0038] FIGS. 9A-B illustrate an exemplary embodiment in which the
implant comprises a first anchor and a second anchor that are
adapted to clamp down on the tissue at the ostium of the left
atrial appendage.
[0039] FIG. 10 illustrates an exemplary embodiment of an implant
with a ratcheting design to secure a portion of the implant in
place.
[0040] FIG. 11 illustrates an alternative ratcheting
embodiment.
[0041] FIG. 12 illustrates an implant with arms connected to a
distal anchor adapted to monitor and/or treat tissue.
[0042] FIGS. 13A-13D illustrate an exemplary embodiment in which
the distal appendage anchor has a general conical expanded
configuration.
[0043] FIGS. 14A-C illustrate an exemplary embodiment of a left
atrial appendage occlusion implant.
[0044] FIG. 14D illustrates a portion of a left atrium,
illustrating the relative positions of left atrial appendage
ostium, mitral valve, and left pulmonary veins ostia.
[0045] FIG. 15 illustrates a front view of an exemplary embodiment
of an occlusion implant.
[0046] FIGS. 16A-C illustrate an exemplary embodiment of an
occlusion implant.
[0047] FIGS. 17A-B illustrate an exemplary embodiment of an
occlusion implant.
[0048] FIG. 18 illustrates a side view of an exemplary embodiment
of an occlusion implant.
[0049] FIGS. 19A and 19B illustrate an exemplary embodiment of an
implant.
[0050] FIGS. 20A-20C illustrate another exemplary embodiment of an
implant.
[0051] FIG. 21 illustrates the concept of an implant with a
plurality of overlapping arms relative to the position of the left
atrial appendage opening.
[0052] FIG. 22 illustrates an exemplary leaflet with barrier
material attached thereto.
[0053] FIG. 23 illustrates an exemplary securing anchor.
[0054] FIGS. 24A and 24B illustrate an exemplary embodiment of an
implant that includes a secondary anchor adapted to be anchored in
the distal region of the left atrial appendage.
[0055] FIG. 25 illustrates an exemplary embodiment of an
implant.
[0056] FIG. 26 illustrates implant with a barrier coupled to a
frame.
[0057] FIG. 27 illustrates implant which includes a barrier, a
frame, a connector, and a bulb.
[0058] FIG. 28 illustrates an alternative embodiment of an
implant.
[0059] FIG. 29 illustrates a further exemplary embodiment of an
implant.
[0060] FIG. 30 illustrate an exemplary embodiment in which the
implant includes a plurality of expanding arms coupled to a
hub.
[0061] FIGS. 31A-F illustrate an exemplary method of access to the
left atrial appendage and an exemplary implant to be implanted
within a patient.
[0062] FIG. 32 illustrates an exemplary embodiment in which the
implant includes non-tapering corkscrew.
[0063] FIG. 33 illustrates the implant from FIG. 32 in a left
atrial appendage.
[0064] FIGS. 34A and 34B illustrate an alternative embodiment in
which implant is adapted to occlude flow into the left atrial
appendage, monitor patient data, and dispense a therapeutic agent
into the left atrial appendage if an arrhythmia is detected.
[0065] FIG. 35 illustrates an alternative embodiment of an implant
similar to the implant shown in FIGS. 34A and 34B.
[0066] FIGS. 36A and 36B conceptually illustrate a frame element
that includes one or more braided elements.
[0067] FIGS. 37A-C illustrate an exemplary embodiment of a medical
device in an expanded, or deployed, configuration that is adapted
to isolate material in the left atrial appendage.
DETAILED DESCRIPTION
[0068] The disclosure herein relates to isolating clots to prevent
them from entering into an atrium of the heart. While the
disclosure focuses on the left atrial appendage ("LAA") and the
left atrium, the systems can be used in the right atrial appendage
and the right atrium. The devices may also be used to close other
undesirable orifices in the heart, such as Atrial Septal Defects
("ASD") or Patent Foramen Ovales ("PFO"). They may also be used in
other portions of a body unrelated to the heart. The disclosure
herein also relates to providing therapy for a detected cardiac
arrhythmia to attempt to prevent the formation of clots within the
appendage.
[0069] One aspect of the disclosure herein relates to LAA occlusion
devices and methods of use. A second aspect of the disclosure
herein provides for intra-atrial or intra-LAA cardiac monitoring
and therapy for a detected arrhythmia.
[0070] The first aspect can be a stand-alone procedure to occlude
the LAA from the left atrium. The second aspect can similarly be a
stand-alone procedure to monitor and provide therapy.
Alternatively, the occlusion device can be integrated with the
therapy aspect. When combined, the occlusion device can be separate
and distinct from the monitoring and therapy components, or they
can be combined into an integrated device.
[0071] FIG. 1 illustrates an exemplary embodiment of a device
adapted to prevent clots from entering the left atrium from the
LAA. FIG. 1 shows a perspective view of device 10 in a deployed
configuration and position blocking off fluid communication between
a left atrium ("LA") and a left atrial appendage ("LAA"). Implant
10 has been deployed adjacent ostium 12 to the LAA, engaging a
portion of LAA wall 14. Implant 10 includes an anchoring element
16, shown with a generally annular shape. Secured to anchoring
element 16, either directly or indirectly, is barrier 18.
[0072] Barrier 18 acts as a primary barrier preventing blood from
flowing into the LAA from the LA. Barrier 18 can be any suitable
material to prevent blood flow into the LAA, such as, for example,
expanded PTFE, PTFE, woven polyester fabric, biocompatible
materials, polyurethane membrane, etc. In FIG. 1, barrier 18 is
secured directly to anchoring element 16, such as by adhesive or
stitching with suture material. Barrier 18 can be reinforced by
frame 22, which in this embodiment includes a plurality of elongate
elements. The elongate element(s) are secured to anchoring element
16 and optionally to barrier, extending across the face of barrier
18 to reinforce the barrier. The frame can be, for example, one
elongate element extending across the face of barrier 18, while it
can also be a plurality of interconnected elongate elements. Other
configurations are within the scope of the disclosure. For example,
the frame can be a plurality of braided wires. The frame can be
secured to the distal side of barrier 18, or it can be disposed
proximally to barrier 18.
[0073] In alternative embodiments barrier 18 acts as a filter,
allowing some blood components to flow into and out of the LAA but
preventing clots from flowing from the LAA into the LA. That is,
barrier 18 can have a porosity to allow some blood components to
flow therethrough while preventing clots (or other non-clot blood
components) from passing therethrough. In some embodiments the
pores can be from, for example, about 60 microns to about 150
microns in diameter. These pores sizes are not intended to be
limiting.
[0074] The anchoring element is adapted to anchor implant 10 in
place within the LAA. Anchoring element 16 is shown as a generally
annularly-shaped component, but can have a variety of shapes.
Anchor 16 provides the expansion force needed to anchor implant 10
in place. The anchor can be made from a shape memory material such
as nitinol, allowing it to be deformed into a delivery
configuration to deliver it to the target location. Upon release
from a delivery sheath or catheter, the anchor reverts to its
memory configuration. The memory configuration can be adapted to
secure the anchor in place based on the outwardly directed force
from the anchor against the tissue. In some embodiments the radial
expansion force is applied by constructing the device from a shape
memory material such as, for example, nickel-titanium
(nitinol).
[0075] FIG. 2 illustrates an exemplary embodiment of an implant
adapted to prevent clots from entering the left atrium from the
LAA. Implant 30 includes anchor 32, frame 38, delivery element 36,
and barrier 35. Anchor 32 can be similar to anchor 16 in FIG. 1,
and frame 38 can be similar to frame 22. Implant 30, in addition to
barrier 35, includes secondary barrier 34, which is coupled to the
distal portion of anchor 32, and is disposed further distally than
barrier 35. Barrier 34 acts as a secondary barrier to blood flow
that prevents blood flow into the LAA. Barrier 34 can be made from
any suitable material to occlude the flow of blood, such as, for
example without limitation, PTFE. Delivery element 36 is adapted to
be releasably coupled to a delivery tool (not shown), allowing
implant 30 to be positioned using the delivery tool and released
therefrom when desired. In alternative embodiments, implant 30 need
not have barrier 35, and only barrier 34 is included in implant 30
to block off the LAA from the left atrium. Additionally, barrier 34
can be taught relative to anchor 32 such that it does not extend
distally relative to anchor. In some embodiments barrier 34 and 35
can be made from the same material and essentially form a 2-ply
barrier.
[0076] FIG. 3 illustrates an exemplary embodiment of an implant to
prevent clots from entering the left atrium from the LAA. Implant
40 includes a first anchor 46, which can be similar to the
anchoring elements shown in FIGS. 1 and 2. Implant 40 also includes
anchoring element 44 which is deployed towards the distal end of
LAA 42. Anchoring element 44 is coupled to anchoring element 46
with struts 48. The struts are coupled to the anchoring elements at
a plurality of locations around the annularly-shaped elements. One
or more of struts 48 can optionally have electrodes 49 disposed
thereon, which can be adapted to monitor cardiac activity and pace
cardiac tissue, which is described in more detail herein. Anchor 44
can be biased to expand to a deployed configuration with a larger
diameter than the section of the LAA in which it is deployed.
Anchor 44, as shown, therefore applies an outwardly directed force
on the LAA to help secure it, and the rest of implant 40, in
place.
[0077] FIGS. 4A-4E illustrate an exemplary embodiment of an implant
adapted to prevent blood flow into the LAA. Implant 50 includes
proximal anchor 54, distal anchor 56, and interconnecting therapy
elements 58. Anchor 54 is disposed at the ostium, or just outside
the ostium of the LAA. The length of therapy elements 58 can be
adjusted, but in this embodiment anchor 56 is shown deployed closer
to the ostium than to the distal end of the LAA. FIG. 4B
illustrates a front view (looking distally) of distal anchor 56,
wherein anchor 56 is coupled to optional barrier 57. Anchor 56 and
barrier 57 can be similar to other anchors and barriers described
herein. FIG. 4C illustrates a front view of proximal anchor 54,
with optional barrier 53. Also shown is delivery element 51 which
is adapted to releasably couple to a delivery tool (not shown).
Barrier 53 does not extend across the delivery element 51. FIG. 4D
illustrate a back view (looking proximally) of anchor 54, wherein
an optional additional barrier layer 59 is secured to anchor 54.
FIG. 4E illustrates a perspective view of implant 50 (LAA not
shown), illustrating a plurality of therapy elements 58 extending
from anchor 54 to anchor 56. Barriers to prevent the flow of blood
are also shown.
[0078] FIG. 5 illustrates an exemplary embodiment of an occlusion
implant. Implant 60 includes a first anchor 62 connected to a
second, distal, anchor 64. Distal anchor 64 resembles a traditional
stent-like design, and can be made from shape memory material as is
known in the art. The anchors are connected by connectors 66, which
can have electrodes 68 secured thereto for monitoring and/or pacing
as described herein. Distal anchor 64 is expanded in the LAA distal
to the ostium to anchor implant 60 securely in place, while anchor
62 is expanded closer to the ostium (either just inside or just
outside the ostium). Anchor 62 can include a barrier layer as
described herein to prevent blood flow into the LAA and to prevent
clots from exiting the LAA. FIG. 6 illustrates a variation on the
embodiment in FIG. 5 in which the device includes barrier 72
secured to expandable anchor 78, which is in the form of an
expandable lattice of material. The implant also includes anchor 71
secured to anchor 74 with connectors 76, which can have electrodes
secured thereto (not shown).
[0079] FIGS. 7A-7C illustrate an exemplary embodiment in which one
or more of the anchors is made from a tube in which portions of the
tube are removed to creates slots therein. FIG. 7A illustrates
tubular element 80 in which material has been removed to form slots
82 therein. By removing material, a plurality of struts are formed
extending from the proximal portion to the distal portion. The tube
can be cut by, for example without limitation, laser cutting
techniques or etching a nitinol tubular element. After the slots
are cut in the tubular element, the struts can be heat set in a
desired memory configuration. For example, FIG. 7B illustrates
struts 84 (only one shown) in an expanded configuration in which a
center region expands outwardly to a greater diameter than the
distal and proximal ends of the struts. The ends of the tubes
create proximal anchor 86 and distal anchor 88, although the tube
can be attached to additional proximal and distal anchors, such as
those described herein. FIG. 7C illustrates an exemplary expanded
configuration in which struts 84 have a smoother curve than the
configuration in FIG. 7B. The force of the struts expanding to
their memory configuration locks the implant in place. While
straight cuts are shown in FIG. 7A, a variety of types of cuts can
be made in the tubular element. For example without limitation,
helical cuts can be made in the tube. The pattern, width,
orientation, etc., of the cuts can be varied, even along the length
of the tubular element, to provide for an expandable configuration
with select properties.
[0080] FIGS. 8A and 8B illustrate an exemplary embodiment of an
implant that can occlude the LAA. Implant 90 is a continuous wire
form, formed from a single wire. The wire forms proximal anchor 92,
distal anchor 94, and connects the anchors with sections 96.
Implant 90 also includes barrier 98 adapted to prevent blood flow
into or out of the LAA. Distal anchor 94 is secured in the LAA to
secure the implant in place, while anchor 92 is adapted to expand
near the ostium such that barrier 98 blocks the flow of blood into
LAA. FIG. 8B illustrates a side view of implant 90.
[0081] FIGS. 9A-B illustrate an exemplary embodiment in which the
implant comprises a first anchor and a second anchor that are
adapted to clamp down on the tissue at the ostium of the LAA. The
two anchors are positioned on opposite side of the ostium tissue,
and once positioned can revert to a closed configuration, clamping
down on the tissue. The clamping action secures the implant in
place and helps provide a seal around the periphery of the implant.
The proximal anchor can include one or more barrier layers as set
forth herein to prevent blood into the LAA. FIG. 9A illustrates
implant 100 comprising proximal anchor 102 and distal anchor 104
connected by elements 106. In their deployed positions, they are
clamped securely around tissue 108 at the ostium of the LAA. FIG.
9B illustrates an alternative concept in which the distance between
anchors 101 and 103 can be adjusted by actuation with delivery
device 107. Delivery device 107 can retract actuation element 109
proximally, causing teeth 111 to ratchet with respect to proximal
anchor 101. Once the tissue at the ostium (not shown) is
sufficiently clamped between the anchors, the delivery device can
be released from actuation element 109. At least one of the anchors
can have a barrier, as shown, to prevent the flow of blood into the
LAA.
[0082] In any of the embodiments above, the proximal anchor (closer
to the atrium) can be thin and have a fabric covering on most of
the anchor but not the entire anchor. The uncovered portion of the
anchor allows for cardiac monitoring and and/or pacing as described
herein. The inner, or distal, disk can be mostly covered by a
fabric.
[0083] FIG. 10 illustrates an exemplary embodiment of an implant
with a ratcheting design to secure a portion of the implant in
place. The implant includes arms 110 and 112 connected to
expandable anchor 118 with connector 120. The proximal portions of
the arms are positioned to be engaging the atrium, as shown. The
distal portions are positioned to be inside the LAA, as shown. Once
in their respective positions, the arms are actuated towards one
another in the direction of the arrows shown in the figure. This
clamps tissue 114 between the arms, securing the implant in place.
The arms can also be adapted with locking features, such that when
engaged they will lock the arms in a locked configuration.
Expandable anchor 118 can be of any suitable anchor that can be
deployed in the LAA and secured against tissue. Once the arms are
moved to their clamped configurations, the blood is blocked from
flowing into the LAA. There may optionally be a barrier layer
material secured to the arms, and adapted such that as the arms are
closed towards one another, the barrier occludes the flow of blood
into the LAA.
[0084] FIG. 11 illustrates an exemplary embodiment of a portion of
implant 130 (distal anchor in LAA not shown) includes ratcheting
arms similar to FIG. 10. Arms 132 and 134 include tissue piercing
elements 138 adapted to pierce through tissue near the ostium to
help more securely anchor arms in place. Implant 130 also includes
delivery element 136 which is adapted to releasably couple to a
ratcheting mechanism of the delivery system to actuate the arms
between open and closed positions.
[0085] FIG. 12 illustrates implant 140 with arms 142 and 144
connected to distal anchor 148 with connector 146. Distal anchor
148 is adapted to be in contact with LAA tissue as shown to monitor
and/or pace tissue as described herein.
[0086] FIGS. 13A-13D illustrate an exemplary embodiment in which
the distal appendage anchor has a general conical expanded
configuration. The general conical configuration more closely
resembles the natural contours of the LAA and can more easily be
anchored in place within the LAA. Implant 160 includes ratcheting
proximal anchor portion 162, as described herein, distal expandable
anchor 168, and connector 166. FIG. 13B illustrates a side view of
a portion of the implant showing the expandable anchor in a
collapsed delivery configuration. FIG. 13C shows an end-view of the
same configuration. FIG. 13D shows an end-view of the distal anchor
in an expanded configuration. Distal anchor 164 has a general
conical shape tapering towards the distal end of the implant. The
anchor is made from a single wire secured to connector, but in
other embodiments more than one wire can be used and different
configurations of the anchor can be used.
[0087] FIGS. 14A-C illustrate an exemplary embodiment of a LAA
occlusion implant. FIGS. 14A-C illustrate a front view (distally
facing), a rear view (proximally facing), and a perspective view,
respectively. Implant 200 includes a proximal portion 220 (see FIG.
14C) and a distal portion 222. Proximal portion 220 includes
leaflets, or blades, 202 and 204, each having a generally
triangular shape. In some embodiments they have a generally
elliptical shape. Once deployed, the leaflets are adapted to engage
a portion of the atrial wall. FIG. 14D illustrates a portion of a
left atrium, illustrating the relative positions of LAA ostium 224,
mitral valve 226, and left pulmonary veins ostia 228. The mitral
valve and ostia to the pulmonary veins are relatively close to the
LAA ostium, and as such any implant positioned in the left atrium
must not obstruct the flow of blood through the mitral valve or the
pulmonary veins. Leaflets 202 are larger than leaflets 204.
Leaflets 204 are aligned with the mitral valve 226 and pulmonary
veins ostia 228, respectively, and are sized such that they do not
obstruct the flow of blood therethrough. Leaflets 202 are not
disposed such that they would block the flow of blood through the
ostia 228 or mitral valve 226 (or any other structure), and as such
they can be larger than leaflets 204. In general, any leaflets
facing the posterior and superior walls are can be longer than
leaflets extending towards the mitral valve and pulmonary veins to
provide for more surface contact with the atrial wall.
Additionally, the leaflets that extend towards the pulmonary veins
can be slightly curved into the base of the pulmonary veins.
[0088] Leaflets 202 each comprise a frame element 201 and a barrier
203. Leaflets 204 are similarly designed. Frame elements 201 have a
general triangular or elliptical shape, and each has two ends
secured to hub 212. Frame elements 201 can be, for example, wire
made from, for example, nitinol. Nitinol, or other material with
shape memory and/or superelastic properties, allows the triangular
wire form to be deformed for loading into a delivery system, with
the wire form converting to the triangular shape upon deployment
due to the shape memory and/or superelastic properties of the
nitinol.
[0089] FIGS. 36A and 36B conceptually illustrate a frame element
that includes one or more braided elements. In this specific
embodiment the frame element is a braided nitinol wire that is heat
set into the deployed configuration shown in FIG. 36B. More than
one wire can be used as well. The braided pattern allows the frame
element to be lengthened into a reduced radial dimension for
loading, as shown in FIG. 36A. The braided frame element is adapted
to then expand in radial dimension upon deployment from a delivery
device through shortening the axial length, as shown in FIG. 36B.
The frame element would be secured to a barrier, such as any of the
barriers described herein.
[0090] Distal portion 222 includes a distal anchor, which in this
embodiment comprises a plurality of anchors 206. Anchors 206 are
similar in shape to the frame elements 201 from leaflets 202 and
204. Anchors 206 can be made from a wire, and can be made from, for
example, nitinol. Each anchor wire has two ends secured to hub 212,
to which leaflets 202 and 204 are also secured. The components can
be secured to hub 212 with any suitable technique, such as bonding,
welding, etc. Anchors 206 are adapted to expand and anchor in the
LAA to secure the implant in place. Any of the distal anchors
described herein can be used as the distal portion of implant 200.
Also, while three anchors 206 are shown, any suitable number of
anchors can be incorporated into implant 200. Additionally, shapes
other than the generally triangular shape can be used. For example,
anchors 206 can have four sides rather than three.
[0091] Leaflets 202 and 204, and anchors 206 are adapted to be
collapsed down into delivery configurations such that they can be
delivered endoluminally to a target location within the heart. In
one exemplary embodiment, the radially outer portions of leaflets
202 are adapted to collapse downward and in the proximal direction
towards one another such that the leaflets are adapted to be
disposed within a delivery catheter, sheath, or other delivery
instrument. The leaflets can be secured to hub such that as they
collapse they overlap one another into a staggered orientation,
easing their collapse. A central portion of frame elements 201 of
each of the leaflets can additionally be adapted to bend outward to
ease in the collapse of frame 201 (shown in phantom on one leaflet
in FIG. 14A). Barriers 203 can have slack built into them so that
frames 101 can collapse. Upon their release from the delivery
instrument, leaflets will revert to their memory configuration
shown in FIGS. 14A-C due to, for example, shape memory properties
of frames 101. Similarly, anchors 206 are adapted to collapse into
a delivery configuration. Anchors 206 collapse distally and inward
towards one another. A central portion of wires 210 can be adapted
to bend along a predetermined location to assist in the collapse of
anchors 206 (shown in phantom for one of the anchors 206 in FIG.
14A). As such, when the proximal portion and distal portions of
implant are collapsed, the proximal portion extends generally
proximally from hub 212, and the distal portion extends generally
distally from hub 212. The large leaflets can additionally
optionally act as cardiac monitoring and pacing electrodes as
described below. Additionally, the frames of the proximal blades
and distal anchors can have electrodes mounted thereon.
[0092] FIG. 15 illustrates a front view of an exemplary embodiment
of an occlusion implant. The design is similar to the design in
FIGS. 14A-C, and therefore not every feature will be described.
Implant 250 includes four larger blades 252 and two smaller blades
254. There is less space between blades 254 than in the design in
FIGS. 14A-C. Blades 254 are similarly sized such that they don't
interfere with blood flow through the pulmonary veins or mitral
valve. The distal portion of implant 250 comprises a plurality of
anchors 256 (six are shown) that are adapted to expand within the
LAA to secure themselves in the LAA. Anchors 256 are struts
extending from tubular element 258. Blades 252 are also secured to
tubular element 258.
[0093] FIGS. 16A-C illustrate an exemplary embodiment of an
occlusion implant. FIG. 16A shows a perspective view, while FIGS.
16B and 16C show side and front views, respectively. Proximal
portion 278 of implant 270 includes four larger blades 272 and two
smaller blades 274 as shown in FIG. 15. Blades 272 and 274 are
coupled to tubular hub 282, which has a lumen therethrough. The
blades bend, or curve, slightly as they extend radially away from
hub 282, which helps them better follow the contour of the atrial
wall. Distal portion 280 of implant 270 includes a plurality of
distal anchor 276 shown as wire forms extending from hub 282. While
eight anchors 276 are shown, more or less anchors can be used.
Anchors 276 each have two generally straight sections and a curved
section in between. Anchors 276 extend slightly distally as they
extend from hub 282.
[0094] FIGS. 17A-B illustrate an exemplary embodiment of an
occlusion implant. Implant 290 includes relatively larger blades
292 and smaller blades 294 secured to hub 298. In the side view of
FIG. 17B, it can be seen that the blades are axially staggered with
respect to the adjacent blade. This can be accomplished by
staggering the attachment points of the blades and hubs and the
angle at which the blade extends from the hub can also be varied.
Blades 292 and 294 are formed such that they extend from the hub
initially in the distal direction, and then bend in the proximal
direction, forming a curved configuration. The distal portion of
implant 290, which is adapted to be anchored in the LAA, includes
spokes, or struts 296, each with an anchoring end 299 adapted to
either pierce the LAA tissue or improve the engagement with the LAA
to better secure the implant in place.
[0095] FIG. 18 illustrates a side view of an exemplary embodiment
of an occlusion implant. Implant 310 includes larger leaflets 312
and smaller leaflets 314, similar to other embodiments herein.
Leaflets 312 are configured such that their radially outer portions
extend further in the proximal direction than the radially outer
portions of leaflets 314. The leaflets can be overlapped in an
appropriate pattern to create a varying structural stiffness or to
create a more dense blood barrier. There can be greater leaflet
redundancy in the center region to cover the LAA ostium and prevent
blood and/or clots to pass through. The configuration of leaflets
312 provides for better engagement with the atrial wall. The
leaflets are secured to hub 316, which has a lumen therethrough.
The distal anchor includes a plurality of spokes 318, each with an
anchoring end as in the embodiment in FIGS. 17A and B.
[0096] FIGS. 19A and 19B illustrate an exemplary embodiment of an
implant. Implant 330 includes two rows of leaflets, similar to a
flower petal design. The leaflets are attached to hub 336. A first
set of leaflets 332 are aligned around hub 336, while leaflets 334
are aligned in a second row around hub 336. Leaflets 334 are
disposed distally relative to leaflets 332. The distal portion of
implant 330 includes spokes 338 to be anchored to the LAA tissue.
FIG. 19B shows a perspective view of the embodiment in the front
view of FIG. 19A. In an alternative embodiment, the leaflets are
coupled to the hub around the periphery of the hub such that the
each leaflet is behind, or proximal to, the adjacent leaflet
(except for one leaflet). This hub attachment pattern can ease in
the collapse of the leaflets for delivery.
[0097] FIGS. 20A-C illustrate another exemplary embodiment. The
leaflets are in two rows, as can be seen in the side view of FIG.
20C. The front, or proximal, row includes leaflets 354 (five are
shown), while back, or distal, row, includes leaflets 352 (five are
shown). From the front view of FIG. 20A, it can be seen that each
leaflet overlaps with the adjacent leaflet. This helps seal off the
LAA and prevents blood flow into the LAA. The leaflets and distal
anchors 356 are each coupled to hub 360, which has a spherical
shape.
[0098] In any of the embodiments herein, the leaflet barrier
material can be adapted to facilitate cell growth over and within
the material. That is, after implantation, cells with grow over and
within the barrier material, further isolating the LAA from the
left atrium. In some of the embodiments, for example in FIGS.
14-20, there are small gaps between adjacent leaflets. This can be
a way of adapting the device such that it acts like a filter rather
than an occlusive barrier. The filter can allow blood to flow into
the LAA from the left atrium, but will still prevent clots from
exiting the LAA into the left atrium. FIG. 21 illustrates the
concept of an implant with a plurality of overlapping arms 382
relative to the position of LAA opening 380. While the leaflets 382
cover most of the opening, small gaps can exist that allow blood to
flow into the LAA, but are not large enough to allow clots to flow
out. The small gaps therefore filter the clots and allow blood to
flow through. FIG. 22 illustrates an exemplary leaflet 382 with
barrier material 384 attached thereto. The leaflet also includes
securing anchor 386 to help secure the leaflet to the atrial wall.
FIG. 23 illustrates the securing anchor 386.
[0099] FIGS. 24A and 24B illustrate an exemplary embodiment of an
implant that includes a secondary anchor adapted to be anchored in
the distal region of the LAA. Implant 400 includes a proximal
portion including leaflets 402 adapted to engage atrial tissue.
Implant 400 also includes anchor elements 404 extending distally
from hub 412. Leaflets 402 and anchoring elements 404 each have two
generally straight portions connected by a curved portion. The
anchoring element may be covered with a barrier, as previously
sited, and may be pleated or ribbed to conform easily to various
frame dimensions throughout the procedure. Adding a barrier to the
anchor elements provides a redundancy, essentially two seal
barriers to the LAA closure device. There are gaps between leaflets
402 allowing blood to flow therethrough but preventing clots from
leaving the LAA. Implant 400 also includes a plurality of struts
408 extending from hub 412 to hub 414. Struts 408 can be formed by
creating slots in a tubular element, leaving hubs 412 and 414 at
the ends of the tubular element. The struts 408 can be biased in
the configuration shown in FIGS. 24A-B. That is, that is their
memory configuration that they can revert to if radially collapsed
during delivery. This is similar to the concept shown in FIGS.
7A-7C. Hubs 412 and 414 define a lumen therein, through which
elongate element 410 is disposed. Elongate element 410 has a lumen
therein that can be accessed to deliver a variety of devices and/or
substances into the LAA through elongate element 410. In FIGS. 24A
and B, implant 400 also includes expandable bulb anchor 406, which
is a material that is adapted to be inflated with an inflation
fluid (liquid or gas). Upon inflation, it creates an interference
fit with the LAA tissue, further assisting in the anchorage of the
implant within the LAA. In some embodiments the bulb 406 is a
Yulex-type material or other suitable material with a relatively
large expansion ratio. In some embodiments the bulb has a memory
configuration to which it is adapted to revert. The bulb would
therefore expand and lock in place within the LAA.
[0100] In some embodiments the bulb includes cardiac monitoring
and/or pacing capabilities described in more detail below. For
example, the bulb can have sensing and/or stimulating electrodes
incorporated therein or on the surface adapted to be in contact
with LAA tissue. For example, bulb 406 can optionally include ring
electrode 416 on the surface to be in contact with LAA tissue.
[0101] In an alternative embodiment to that shown in FIGS. 24A-B,
the implant does not include a bulb, but rather a substance can be
delivered into the LAA through elongate member 410, and out the
distal end of hub 414. This concept is described in more detail
herein.
[0102] FIG. 25 illustrates an exemplary embodiment. Implant 420
include barrier 422 adapted to prevent blood from entering the LAA
(or at least preventing clots from leaving the LAA). Barrier 422 is
reinforced by frame 424, which includes a plurality of reinforcing
elements. Frame 424 is coupled to hub 426, from which struts 428
extend to hub 430. The struts and hubs can be formed as described
herein or in any other suitable manner. FIG. 26 illustrates implant
440, with barrier 444 coupled to frame 442. Frame 442 is secured to
hub 446, from which struts 450 extend to hub 448. Elongate element
452 and bulb 454 can be similar to their equivalents described in
FIGS. 24A and 24B.
[0103] FIG. 27 illustrates implant 460, which includes barrier 462,
frame 464, connector 466, and bulb 470. Connector 466 is a coil
spring, which adds flexibility to the implant. Bulb is coupled to
connector 466.
[0104] In some embodiments, once the anchors are secured around the
LAA ostium and any other anchors are secured within the LAA, a
procedure to verify the LAA is sealed from the left atrium can be
performed. For example, in the embodiment shown in FIGS. 24A and
24B, once the bulb is expanded, dye can be injected through a lumen
in the delivery device (e.g., a delivery catheter), through
elongate element 410, and out a distal port in bulb 406. The LAA is
sealed off from the atrium if, under fluoroscopy, it is determined
that no injection contrast escapes the LAA.
[0105] In some embodiments, once a barrier is established between
the left atrium and the LAA, a casting is injected through the
distal port of the implant into the LAA. For example, the casting
can be an electrically conductive casting or a soft polymer
casting. In one particular example, ethylene vinyl alcohol ("EVOH")
is injected with a conductive filler or a conductive polymer. The
delivery catheter remains in place until the casting material has
solidified and it cannot enter into the bloodstream.
[0106] As an alternative to a casting material, in some embodiments
a sclerosant material is injected through the implant into the LAA.
The sclerosant causes the LAA to shrink. The delivery catheter
remains in place until the sclerosant is no longer active and
cannot get into the blood stream.
[0107] FIG. 28 illustrates an alternative embodiment. Implant 480
includes ostium anchor 482 and LAA anchor 484. Anchor 482 includes
barrier 488 that blocks the LAA from the atrium. Anchor 486 has a
generally helical design. Anchor material 486 can be, for example
without limitation, a wire, a ribbon material, and can be heat set
to expand to an expanded configuration to anchor it within the LAA.
In some embodiments anchor material 486 is a ribbon material coated
with a hydrogel to enhance the tissue/anchor adherence. Optionally,
a clotting agent is added to the hydrogel material. Optionally,
cardiac diagnostic or monitoring components are located in anchor
482 to increase the electrical conduction between the monitoring
component and the atrial wall.
[0108] FIG. 29 illustrates a further exemplary embodiment. The
implant includes hydrogel capsule 502, secured in place within the
LAA via struts or arms 504 and 508. The implant also includes
diagnostic component 506. Arms 508 help anchor the implant in place
and also connect diagnostic component 506 to atrial tissue.
Diagnostic component 506 can monitor cardiac signals via arms 508,
and can store date therein or can automatically transmit that date
to an external device without storing it. The cardiac data can be
accessed wirelessly using MEMS, or in some embodiments there can be
direct access to diagnostic component 506 during a catheterization
procedure. Capsule 505 can be filled with a hydrogel, or for
example, a hydrogel/cyanoacrylate combination or other medical
grade adhesives. Diagnostic component 506 can be adapted for
long-term monitoring (e.g, weeks, months, or years). Subjects in
which the implant can be implanted may suffer from atrial
fibrillation. Diagnostic component 506 allows a physician to
continuously monitor cardiac data to detect atrial fibrillation to
prevent the patient from suffering a stroke. The diagnostic
component can additional be adapted to communicate with an external
device. The diagnostic component can continuously transmit patient
information, such as cardiac electrical activity, to the external
device. The external device could be worn by the patient or could
be a physician's computer. The external device can, based on the
patient data, detect atrial fibrillation. The external device can
be adapted to transmit a signal to diagnostic component, with
instructions to administer a therapy to the patient to attempt to
disrupt the cardiac arrhythmia. In some embodiments the diagnostic
component is adapted to detect the occurrence of atrial
fibrillation and initial a therapy to disrupt the cardiac
arrhythmia. Diagnostic component 506 can additionally be adapted to
monitor other patient information, such as blood pressure, etc.
Exemplary details of the cardiac monitoring and therapy are
provided below.
[0109] FIG. 30 illustrate an exemplary embodiment in which implant
530 includes a plurality of expanding arms 532 coupled to hub 533.
At the end of each of the arms is mechanical lock 534. Coiled wire
536 is coupled to hub 533 and extends in the proximal direction
from hub 533. Arms 532 are adapted to expand and engage LAA tissue
to lock the implant in the LAA. Coiled element 536 is adapted to
engage tissue surrounding the LAA ostium and is adapted to monitor
cardiac electrical activity and optionally pace the tissue to
disrupt atrial fibrillation and prevent stroke. In some embodiments
the implant relies on MEMS for the diagnostic components and
optional wireless communication. Implant 530 can be adapted to
incorporate any features disclosed herein, such as being adapted to
deliver a casting material into the LAA to form a plug filling the
LAA space.
[0110] FIGS. 31A-F illustrates an exemplary method of access to the
LAA and an exemplary implant to be implanted within a subject. In
FIG. 31A, delivery sheath 552, implant sheath 556, and guidewire
554 gained access to the LAA via a femoral vein, inferior vena
cava, right atrium, fossa ovalis, and left atrium approach, an
approach known in the art. The LAA can be accessed via other routes
as well. Additionally, the implant can be positioned surgically.
Other minimally invasive approaches can be used. In FIG. 31B,
guidewire 554 is extended into the LAA as shown. Steerable delivery
sheath 552 and implant sheath 556 are tracked over guidewire 554
into the LAA into the position shown in FIG. 31B. Once the distal
end of the steerable sheath 552 is within the LAA, implant sheath
556 is then exposed. As shown in FIG. 31C, corkscrew drive 558 is
rotated causing the corkscrew portion 562 of the implant to be
deployed from the distal end of the implant sheath 556. The
corkscrew has a tapered configuration. As the corkscrew is
advanced, plug 564 is exposed and the rotation of corkscrew 562
penetrates the LAA tissue, while applying very little tensile or
compressive forces on the LAA. Plug 564 is made of a sponge-type
material adapted to expand in diameter in the presence of blood.
FIG. 31D shows the corkscrew 562 fully deployed/rotated and the LAA
tissue tapered down the corkscrew until it is "pinched" between the
corkscrew and the ID plug. In FIG. 31E, once the LAA tissue is
securely grasped by the implant, the entire system is retracted
proximally. This actuation causes the LAA to collapse and compress.
The corkscrew and plug provide a grasping mechanism which supports
the weak LAA tissue to prevent tearing during collapse and
compression. The final step in the method is to deploy anchoring
barrier 570 in the left atrium against the atrial wall, as shown in
FIG. 31F. Note that the sequence of deployment is easily altered to
deploy 570 first, therefore sealing the entrance to the LAA from
the atrial pressure and then affixing the corkscrew to the distal
area of the LAA. This would potentially address safety concerns of
the corkscrew causing the LAA to leak. The barrier maintains a
constant tension on the collapsed/compressed LAA. The barrier, as
shown, is a braided nitinol material with a liner made from, for
example, ePTFE. Other barrier material and designs can be used. The
liner blocks blood flow into the LAA. The corkscrew drive is the
released from the proximal portion of the implant, leaving the
implant within the patient.
[0111] FIG. 32 illustrates an exemplary embodiment in which the
implant includes corkscrew 572 that is not tapered as in the
embodiment in FIG. 31. At the distal end of corkscrew is bulb 578
that can prevent damage to LAA tissue. The implant also includes
plug 574 and proximal anchoring portion 576, comprising a braided
material, such as nitinol, and barrier 578 adapted to block blood
flow into the LAA. FIG. 33 illustrates the implant from FIG. 32 in
a LAA.
[0112] The systems herein can also include a cardiac monitoring
component to monitor one or more patient parameters. In some
embodiments the systems includes a monitoring component adapted to
monitor electrical activity of the heart over time. The electrical
activity of the heart can be monitored to detect arrhythmias, such
as atrial fibrillation. In some embodiments the systems herein are
adapted to provide a therapy to treat the detected arrhythmia. For
example, if an arrhythmia is detected, the system can be adapted to
pace cardiac tissue through electrical stimulation thereof.
Alternatively, or in addition to, the systems can be adapted to
deliver a therapeutic compound to the patient in the event an
arrhythmia is detected. The monitoring and/or therapy components of
the systems can optionally be a stand-alone device and not
integrated into a LAA occlusion device.
[0113] In some embodiments the system includes a monitoring
component that monitors, or senses, cardiac electrical activity.
The sensing components can be positioned within the LAA and/or the
left atrium, and are adapted to be in contact with cardiac tissue
to sense the electrical activity. The system can monitor ECG data
from the patient. In some embodiments the sensing component is an
electrode or an array of electrodes in contact with cardiac tissue
to monitor electrical activity of the heart.
[0114] The system is adapted to process the electrical activity
data and detect atrial fibrillation from the monitored data. For
example, the system can monitor ECG data and detect AF by, for
example, the absence of P waves, with unorganized electrical
activity in their place. Irregular R-R intervals due to irregular
conduction of impulses to the ventricles can also be an indication
of atrial fibrillation. The system can include software adapted to
automatically detect the occurrence of AF. The system can also be
adapted such that electrical activity data is transmitted to health
care professionals whose interpretation of the electrical activity
data can supplement or replace the automated detection process.
[0115] The detection component can be integrated with the
monitoring components such that it is within the heart.
Alternatively the processing component can be disposed outside the
heart, and optionally external to the patient. If outside the
heart, the processing component can be secured to, for example, the
epicardium, or it could be a device that is worn by the patient
close to the heart and that is in wireless communication with the
intra-cardiac device.
[0116] In some embodiments the processing components are disposed
within the heart and part of the monitoring device. The
intra-cardiac system can then monitor and detect atrial
fibrillation from a device implanted completely within the LAA
and/or the left atrium.
[0117] In some embodiments the processing components of the system
are disposed in a device external to the heart such that monitored
patient data is transmitted, wirelessly or wired, to the processing
component. If AF is detected therapy will likely be administered as
soon as possible, and thus the monitoring component substantially
continuously transmits data to the processing component such that
substantially real-time detection of AF occurs.
[0118] If AF is detected, the system can be adapted to administer
therapy to restore normal electrical activity to the heart. In some
embodiments the therapy is electrical pacing therapy administered
by, for example, pacing electrodes disposed within the LAA and/or
left atrium. Electrical impulses can be delivered by electrodes
that contact the cardiac muscle to pace the appendage or atrium for
a short-term period of time to treat, for example, AF, atrial
tachycardia, sick sinus rhythm, etc. In some embodiments pacing
occurs at regular intervals. For example, pacing can occur for
about 30 to about 90 seconds and occurs about every 6 to about
every 12 hours. These numerical ranges are merely exemplary.
[0119] In some embodiments the therapy comprises delivering a
therapeutic agent into the heart upon the detection of an
arrhythmia. The implantable system can include a drug reservoir for
delivery of one or more anti-atrial fibrillation drugs if the
patient goes into AF. In some embodiments the LAA occlusion device
is placed near the ostium of the LAA, while the cardiac monitor and
drug reservoir are disposed on the appendage side of the implant.
The cardiac monitor is adapted to release a prescribed amount of
the therapeutic agent in the event AF is detected and lasts longer
than a prescribed period of time. The therapeutic agent
administered includes anti-arrhythmic and/or rate control and/or
anticoagulation agents for AF. An example is Vernakalant, an
investigational drug under regulatory review for the acute
conversion of AF. Exemplary rate control agents and doses include
Metoprolol (e.g., about 50 to about 100 mg), Atenolol (e.g., about
50 to about 100 mg), Propranolol (e.g., about 40 to about 80 mg),
Acebutolol (e.g., about 200 mg), Carvedilol (e.g., about 6.25 mg),
Diltiazem (e.g., about 180 to about 240 mg), Verapamil (e.g., about
180 to about 240 mg), and Digoxin (e.g., about 0.125 mg). Exemplary
rhythm control agents and doses include Propafenone (e.g., about
450 mg), Flecainide (e.g., about 200 mg), Sotalol (e.g., about 240
mg), Dofetilide (e.g., about 500 mcg), Amiodarone (e.g., about 200
mg), Quinidine (e.g., about 600 to about 900 mg). In some
embodiments innovative anti-arrhythmic agents can be used with
unconventional anti-arrhythmic mechanisms, such as stretch receptor
antagonism, sodium-calcium exchanger blockade, late sodium channel
inhibition, and gap junction modulation. These therapies have not
yet reached clinical studies in AF but reports look promising.
[0120] In FIG. 1, anchoring element 16 can incorporate sensing
elements such as ring electrodes disposed on and around anchoring
element 16. Anchoring element 16 can also incorporate pacing, or
stimulating, electrodes disposed thereon. Any suitable anchoring
element or anchoring structure described herein can be adapted to
include one or more electrodes for monitoring and/or pacing. For
example, in FIG. 3, anchor 44 can be adapted to have one or more
electrodes disposed thereon. The electrodes would be adapted to be
in contact with LAA tissue to monitor and/or pace the tissue.
Similarly, distal anchor 56 can also comprise electrodes disposed
thereon to monitor and/or pace LAA tissue.
[0121] In some embodiments, even if there is an anchoring structure
within the LAA, an anchoring structure adjacent the LAA ostium can
have electrodes disposed thereon to monitor and/or pace tissue
adjacent the ostium. For example, in the embodiment in FIG. 3,
anchoring structure 46 can include electrodes disposed thereon. In
FIG. 12, distal anchor can include monitoring and/or pacing
electrodes thereon. In some embodiments, connector 146 can be used
as either the anode or the cathode and an electrode within distal
anchor 148 is the opposite of the electrode in connector 146.
Connector 146 is electrically coupled to the electrode in distal
anchor 148.
[0122] FIGS. 14A-27 illustrate exemplary embodiments of how
occluding devices described herein can be adapted to include
monitoring and therapy components. For example, leaflets 202 in the
embodiment in FIGS. 14A-C can be adapted to include sensing and/or
pacing electrodes. When the leaflets are expanded in the left
atrium, the distal sides of the leaflets engage atrial tissue. The
leaflets, and optionally frame 101, can have electrodes disposed
therein and can be in electrical connection to hub 212 to other
components that can provide power. Additionally, in the embodiment
in FIGS. 16A-16, hub 282 has a lumen therein that can be adapted to
receive an elongate member that is to be disposed within the LAA.
The elongate member can have one or more monitoring and/or pacing
electrodes thereon to be in contact with LAA tissue. In FIGS. 24A
and 24B, elongate element 410 can be the cathode or anode while
electrode 416 of bulb 406 is the opposite thereof. Electrode 416 is
adapted to be in contact with LAA tissue and is adapted to monitor
and/or pace the cardiac tissue.
[0123] While the implanted devices can be incorporated with sensing
and/or stimulating functionality, the implanted devices, in some
embodiments, include circuitry to process the monitored patient
data and detect an arrhythmia. Processing the data can include
known techniques, including filtering and amplifying a signal.
Algorithms stored in the device can determine if, based on the
data, AF is occurring. Upon the detection of an arrhythmia, the
system can be adapted to automatically deliver a therapy, whether
it is electrical pacing, drug delivery, or some other type of
therapy.
[0124] In some embodiments the processing and detecting steps occur
in a device external to the heart, whether they are underneath the
patient's skin or external to the patient. For example, an external
device can be secured to the patient using a harness such that the
device is secured comfortably near the patient heart. The monitored
data is transmitted to the external device, which can include the
processing and detection components. Once an arrhythmia is
detected, the external device then communicates a signal to the
internal device to initiate the therapy. In some instances the
data, raw or processed, is further transmitted to a remote
location. For example, the data can be transmitted to a physician
for review. In some instances the detection algorithm can be
reprogrammed as needed, perhaps to provide better more accurate AF
detection.
[0125] The implanted device or any external device can include
memory to store data, either temporarily or permanently. The
implanted device can stored a certain amount of data, such as in a
first-in-first-out process, or it can transmit data to an external
data, which then stores the data. In some embodiments only data
just before, during, and following AF is desired. The system can be
adapted to store in memory only data from that specific period of
time. The stored data can additionally be reviewed by a health care
provider as desired.
[0126] The implantable device can optionally include a power
source, which is optionally rechargeable (such as by inductive
charging). The power source can power the sensing and/or pacing
electrodes, or any other electrically driven activities performed
by the implant. The power source is disposed in the implant and is
in electrical communication with any monitoring and/or pacing
electrodes.
[0127] The device can be adapted with additional sensors to acquire
data to calculate or determine any of the following: AF burden
(i.e., the time the patient is in AF as compared to sinus rhythm),
left atrial pressure, temperature, transthoracic impedance
(surrogate for pulmonary fluid status, i.e., "CHF"), impending
atrial fibrillation or ventricular fibrillation. The implant can
also include a pulse counter.
[0128] FIGS. 34A and 34B illustrate an alternative embodiment in
which implant 600 is adapted to occlude flow into the LAA, monitor
patient data, and dispense a therapeutic agent into the LAA if an
arrhythmia is detected. Implant 600 include expandable frame 606,
which has a general mushroom configuration in an expanded
configuration. The frame is secured to barrier 604, which is
adapted to prevent blood from entering the LAA. Barrier 604 only
covers a proximal portion of frame 604, leaving a distal portion of
frame 606 uncovered by the barrier. The open end of the frame faces
into the LAA. The implant also includes delivery element 602 that
is adapted to be releasably coupled to a delivery tool (not shown).
Implant 600 also includes cardiac monitor and therapeutic agent
reservoir component 608. Component 608 is secured to the inside of
the implant 600. That is, component 608 is only exposed to the
inside of the LAA and not the left atrium. The cardiac monitoring
component is electrically coupled to LAA tissue via leads 610 and
monitors atrial activity, such as electrograms. When the detection
component (whether it is integrated with implant 600 or disposed
external to the heart) detects an arrhythmia such as atrial
fibrillation, component 608 can be programmed to automatically
release a dose of an anti-atrial fibrillation therapeutic agent.
The drug reservoir could be a reservoir with a valve that when
opened, releases the agent into the LAA. The valve, or any suitable
actuatable element, can be electrically powered by the power source
within implant 600 to open to release the agent into the LAA.
[0129] FIG. 35 illustrates an alternative embodiment of implant 700
that is similar to implant 600 shown in FIGS. 34A and 34B. Implant
700 includes expandable frame 702, barrier 704, which is adapted to
prevent blood from entering the LAA. Barrier 704 only covers a
proximal portion of frame 702, leaving a distal portion of frame
uncovered by the barrier. The open end of the frame faces into the
LAA. The implant also includes delivery element 708 that is adapted
to be releasably coupled to a delivery tool (not shown). Implant
700 also includes cardiac monitor and therapeutic agent reservoir
component 706, which can provide the same functions as component
608 in the embodiment in FIGS. 34A and 34B.
[0130] FIGS. 37A-C illustrate an exemplary embodiment of a medical
device in an expanded, or deployed, configuration that is adapted
to isolate material in the left atrial appendage. Device 800
includes anchoring portion 802 and barrier portion 804. Anchoring
portion 802 includes four distal anchors 806 and four proximal
anchors 810 (only two can be seen), all of which are coupled to hub
808. Barrier portion 804 includes proximal barrier 814 and distal
barrier 812. Distal barrier 812 is secured to distal anchors 806,
while proximal barrier 814 is secured to distal anchors 810. In
this embodiment they are secured with sutures, as shown.
[0131] Each of the distal and proximal anchors has a looped
configuration, the two ends of which are secured to hub. The loops
are longer than they are wide. In their expanded configurations,
the anchors 806 and 810 extend substantially radially outward from
hub 808, and are generally orthogonal to the longitudinal axis of
hub 808. In other words, in the side view shown in FIG. 37B, the
anchoring portion resembles the letter "H," with the distal anchors
806 shorter than proximal anchors 810. All of the distal anchors
806 are generally in the same plane, but are constructed to be
appropriately flexible to conform to the amorphous anatomy of the
left atrial appendage, which is generally orthogonal to the
longitudinal axis of hub 808, which can be seen in the side view of
FIG. 37B. All of the proximal anchors are also generally in a
single plane, which is generally orthogonal to the longitudinal
axis of hub 808.
[0132] In this embodiment the anchoring portion, including the
eight anchors and the hub, is formed by laser cutting a single
nitinol tube. The anchors and hub need not be formed from the same
starting material, and can be secured to one another, such as by
welding. The hub and the anchors need not be the same type of
material. Materials other than nitinol can be used, and other
cutting methods can be used.
[0133] In this embodiment, after the necessary material has been
removed during the laser cutting process, the eight anchors are
heat set in the deployed configurations shown in FIGS. 37A-C, such
that they are substantially orthogonal to hub 808. Barrier 814 and
barrier 812 are then secured to the anchors. In this embodiment
they are sutured to the anchors, with the sutures as shown. Other
methods of securing the anchors and barriers can be used. The
proximal anchors 810 are secured to proximal barrier 814 such that
proximal anchors 810 are on the distal side of proximal barrier
814. Distal anchors 806 are secured to distal barrier 812 such that
distal anchors 806 are disposed on the distal side of distal
barrier 812. For distal anchors 806 to be on the distal side of
distal barrier 812, there is a central hole in distal barrier
812.
[0134] The barriers can be a polyester material such as
polyethylene terephthalate ("PET"; trade name Dacron.RTM.). The
barriers can be other suitable materials, such as PTFE.
[0135] Proximal barrier 814 has pleats 816 formed therein between
anchors 810. The pleats, or other rib formations, can help reduce
the amount of material in the barrier, which can make it easier
when the device is loaded into a delivery device. The pleats can
help reduce the delivery profile of the device. The pleats or ribs
also make it easier to accommodate dimensional changes of the
anchor elements with compression on the barrier in the delivery
configuration and tension on the barrier in the deployed
configuration. Maintaining a low barrier thickness can also ease
the loading process and maintain a minimal delivery profile of the
device. The barrier material can be selected to have a specific
porosity. The device includes two barriers 814 and 812, which
effectively creates a two-ply barrier, and thereby reduces the
amount of material that can escape the left atrial appendage and
into the left atrium.
[0136] The barriers are adapted to prevent blood flow into the LAA,
although they could be adapted to filter blood such that they
prevent clots from flowing from the LAA into the left atrium. In
alternative embodiments the device does not include distal barrier
812, such that the device only include a proximal barrier.
[0137] In an exemplary method of use, the device is used to occlude
the left atrial appendage such that material in the left atrial
appendage cannot enter the left atrium. Device 800 is first loaded
into a delivery configuration in a delivery device, such as a
catheter. Distal anchors 806 are deformed by collapsing them toward
the longitudinal axis of the hub, so that they extend generally
distally from the hub and are moved closer to one another. Proximal
anchors 810 are also collapsed towards the longitudinal axis of the
hub, moving them closer together such that they extend
substantially proximally from the hub. The reconfiguration of
proximal anchors 810 causes the barrier material 814 to bunch up,
which is minimized by pleats, ribs, or other similar features.
Pleats or ribs can also be incorporated into the distal barrier
812. The device can be front-loaded into a distal end of the
delivery device, such that the proximal anchors are deformed before
the distal anchors.
[0138] In use, after the device has been advanced within the
patient adjacent the left atrial appendage (as described above),
the distal anchors and distal barrier are first deployed from the
delivery device into the left atrial appendage. Anchors 806 deform
towards their deployed configuration shown in FIGS. 37A-C, such
that they extend radially from hub 808. As they deform, they will
engage left atrial appendage tissue, anchoring the distal portion
of the device in the left atrial appendage. Once the position of
the anchors in confirmed using one or more imaging techniques, the
proximal anchors are then deployed from the delivery device such
that the proximal anchors engage left atrial tissue and secure the
proximal barrier over the left atrial appendage ostium. Material in
the left atrial appendage cannot escape the appendage and enter the
atrium. The proximal anchors can have a deployed configuration in
which they extends slightly distally relative to the hub, such that
they apply a slight distally directed force on the atrial tissue,
which helps anchor device in place relative to the atrial tissue.
Similarly, the distal anchors can be biased to extend slightly in
the proximal direction relative to the hub to apply a slightly
proximally directed force on the left atrial appendage. In some
embodiments the distal anchors and proximal anchors provide a
slight or substantially clamping effect on the tissue at the
ostium, which helps secure the device in place.
[0139] It should be noted that before the proximal anchors are
deployed, if the position of the deployed distal anchors is not
optimal, the catheter can be advanced distally, deforming the
distal anchors forward towards their delivery configurations, while
recapturing the distal anchors within the delivery device.
[0140] Device 800 can similarly be adapted to include sensing
and/or treatment features to sense and treat cardiac arrhythmias.
For example, one or more of the anchors 810 or 806 can have one or
more electrodes disposed thereon adapted to delivery energy to
cardiac tissue to pace the tissue in the event of a detected atrial
fibrillation. Alternatively, hub 808 can have a cylindrically
shaped drug delivery device disposed therein, which is adapted to
deliver a drug or other agent into the left atrial appendage,
examples of which are disclosed above.
[0141] While preferred embodiments of the present disclosure have
been shown and described herein, it will be obvious to those
skilled in the art that such embodiments are provided by way of
example only. Numerous variations, changes, and substitutions will
now occur to those skilled in the art without departing from the
disclosure. It should be understood that various alternatives to
the embodiments of the disclosure described herein may be employed
in practicing the disclosure.
* * * * *