U.S. patent application number 13/772801 was filed with the patent office on 2013-06-27 for heart occlusion devices.
This patent application is currently assigned to W.L. GORE & ASSOCIATES, INC.. The applicant listed for this patent is W.L. Gore & Associates, Inc.. Invention is credited to Zahid Amin, Edward H. Cully, Warren Cutright, Coby C. Larsen, Steven J. Masters, Edward E. Shaw.
Application Number | 20130165967 13/772801 |
Document ID | / |
Family ID | 48655311 |
Filed Date | 2013-06-27 |
United States Patent
Application |
20130165967 |
Kind Code |
A1 |
Amin; Zahid ; et
al. |
June 27, 2013 |
HEART OCCLUSION DEVICES
Abstract
This disclosure is directed to an aperture occlusion device and
a method for occluding an aperture, including a perimembranous
ventricular septal defect. The aperture occlusion device includes a
wire frame element. The wire frame forms geometric shapes that
include an occluder region and a securing region. The occluder
region and the securing region are separated by an attachment
region including a waist. The occluder region and securing region
can include membranous coverings. The device can be attached to a
delivery hub. The wires forming the occluder region and securing
region can have a shape-memory capability such that they can be
collapsed and distorted in a sheath during delivery, but resume and
maintain their intended shape after delivery.
Inventors: |
Amin; Zahid; (Omaha, NE)
; Cully; Edward H.; (Flagstaff, AZ) ; Cutright;
Warren; (Flagstaff, AZ) ; Larsen; Coby C.;
(Flagstaff, AZ) ; Masters; Steven J.; (Flagstaff,
AZ) ; Shaw; Edward E.; (Flagstaff, AZ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
W.L. Gore & Associates, Inc.; |
Newark |
DE |
US |
|
|
Assignee: |
W.L. GORE & ASSOCIATES,
INC.
Newark
DE
|
Family ID: |
48655311 |
Appl. No.: |
13/772801 |
Filed: |
February 21, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13210198 |
Aug 15, 2011 |
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13772801 |
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12400445 |
Mar 9, 2009 |
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13210198 |
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61034772 |
Mar 7, 2008 |
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Current U.S.
Class: |
606/213 |
Current CPC
Class: |
A61B 2017/12095
20130101; A61B 2017/00615 20130101; A61B 17/0057 20130101; A61B
2017/00575 20130101; A61B 2017/00597 20130101; A61B 2017/00632
20130101; A61B 17/12122 20130101; A61B 2017/00592 20130101; A61B
17/12145 20130101; A61B 2017/00606 20130101; A61B 17/12172
20130101; A61B 2017/00243 20130101; A61B 2017/00623 20130101; A61B
17/12022 20130101; A61B 2017/00867 20130101; A61B 2017/12054
20130101; A61B 2017/00557 20130101; A61B 2017/00853 20130101 |
Class at
Publication: |
606/213 |
International
Class: |
A61B 17/00 20060101
A61B017/00 |
Claims
1. A single-disc device for occluding an aperture within a body of
a patient, comprising: an occluder region comprising a frame
element, the frame element comprising a plurality of wire portions,
the plurality of wire portions configured to form a disc at a first
end of the single-disc device, wherein the disc generally defines a
disc plane; an attachment region with an axis that extends
transversely to the disc plane, the attachment region comprising an
occluder region attachment end and a securing region attachment
end, the occluder region attachment end being connected to the
occluder region; and a securing region connected to the securing
region attachment end and at a second end of the single-disc
device, the securing region comprising one or more securing
members, wherein a major axis of each of the one or more securing
members extends transversely to the axis of the attachment region
and all major axes of the one or more securing members are
generally located within a circular sector having an arc of about
180 degrees or less.
2. The single-disc device of claim 1, wherein the major axes of the
securing members are spaced symmetrically within the circular
sector having an arc of about 180 degrees or less.
3. The single-disc device of claim 1, wherein the one or more
securing members each comprise one or more wire loops or wire
prongs.
4. The single-disc device of claim 1, wherein the circular sector
has an arc of 150 degrees or less.
5. The single-disc device of claim 1, wherein the major axis of
each of the one or more securing members extends at an angle
between 80 and 100 degrees with respect to the axis of the
attachment region.
6. The single-disc device of claim 1, wherein the securing region
comprises three or more securing members.
7. The single-disc device of claim 1, wherein the disc plane
extends at an angle between 0 to 5 degrees with respect to the
major axis of at least one of the one or more securing members.
8. The single-disc device of claim 1, wherein the disc plane
extends at an angle between 5 to 15 degrees with respect to the
major axis of at least one of the one or more securing members.
9. The single-disc device of claim 1, wherein the occluder region
comprises a membrane configured to inhibit passage of blood,
wherein the membrane covers at least a portion of the disc.
10. The single-disc device of claim 9, wherein the membrane
comprises a fluoropolymer.
11. The single-disc device of claim 9, wherein the membrane
comprises polytetrafluoroethylene.
12. The single-disc device of claim 9, wherein the membrane
comprises expanded polytetrafluoroethylene.
13. The single-disc device of claim 1, wherein the occluder region
further comprises an expandable balloon configured to restrict
fluid flow through the aperture.
14. The single-disc device of claim 1, wherein the occluder region
comprises at least one anchor.
15. The single-disc device of claim 1, comprising one or more
visual indicators configured to identify the orientation of the
securing region.
16. The single-disc device of claim 1, wherein the disc plane
extends at an angle between 75 to 105 degrees with respect to the
axis of the attachment region.
17. The single-disc device of claim 1, wherein the first end is at
the proximal end of the single-disc device and the second end is at
the distal end of the single-disc device.
18. A method of occluding a cardiac defect, comprising: providing a
single-disc device comprising: an occluder region comprising a
frame element, the frame element comprising a plurality of wire
portions, the plurality of wire portions configured to form a disc
at a first end of the single-disc device, wherein the disc
generally defines a disc plane; an attachment region with an axis
that extends transversely to the disc plane, the attachment region
comprising an occluder region attachment end and a securing region
attachment end, the occluder region attachment end being connected
to the occluder region; and a securing region connected to the
securing region attachment end and at a second end of the
single-disc device, the securing region comprising one or more
securing members, wherein a major axis of each of the one or more
securing members extends transversely to the axis of the attachment
region and all major axes of the one or more securing members are
generally located within a circular sector having an arc of 180
degrees or less; configuring the single-disc device in a delivery
configuration and advancing the single-disc device to a delivery
site; and deploying the single-disc device at the delivery
site.
19. The method according to claim 18, comprising coupling the
single-disc device to a delivery catheter.
20. The method according to claim 19, comprising inserting the
single-disc device and the delivery catheter into a delivery
sheath.
21. The method according to claim 20, wherein the frame element
collapses as the single-disc device is inserted into the delivery
sheath.
22. The method according to claim 20, wherein deploying the
single-disc device comprises advancing the single-disc device
through the delivery sheath, such that at least a portion of the
single-disc device exits the delivery sheath distal of the delivery
sheath.
23. The method according to claim 22, wherein the frame element
expands as the single-disc device exits the delivery sheath.
24. The method according to claim 20, wherein deploying the
single-disc device comprises pulling the delivery sheath away from
the cardiac defect while maintaining a position of the single-disc
device.
25. The method according to claim 18, wherein deploying the
single-disc device substantially occludes the cardiac defect.
26. A system for occluding an aperture within a body of a patient,
comprising: a single-disc occluder device comprising: an occluder
region comprising a frame element, the frame element comprising a
plurality of wire portions, the plurality of wire portions
configured to form a disc at a first end of the single-disc device,
wherein the disc generally defines a disc plane; an attachment
region with an axis that extends transversely to the disc plane,
the attachment region comprising an occluder region attachment end
and a securing region attachment end, the occluder region
attachment end being connected to the occluder region; and a
securing region connected to the securing region attachment end and
at a second end of the single-disc device, the securing region
comprising one or more securing members, wherein a major axis of
each of the one or more securing members extends transversely to
the axis of the attachment region and all major axes of the one or
more securing members are generally located within a circular
sector having an arc of 180 degrees or less; a deployment wire
releasably attached to the first end of the single-disc device; a
delivery catheter comprising a sheath configured to contain the
deployment wire and the single-disc occluder device arranged in a
delivery configuration, the delivery catheter configured to advance
the single-disc device to a delivery site; and an actuator device
attached to a proximal end of the delivery catheter, the actuator
device being configured to remotely control deployment of the
single-disc device at the delivery site.
27. A method of occluding a blood vessel, comprising: providing a
single-disc device comprising: an occluder region comprising a
frame element, the frame element comprising a plurality of wire
portions, the plurality of wire portions configured to form a disc
at a first end of the single-disc device, wherein the disc
generally defines a disc plane; an attachment region with an axis
that extends transversely to the disc plane, the attachment region
comprising an occluder region attachment end and a securing region
attachment end, the occluder region attachment end being connected
to the occluder region; and a securing region connected to the
securing region attachment end and at a second end of the
single-disc device, the securing region comprising one or more
securing members, wherein a major axis of each of the one or more
securing members extends transversely to the axis of the attachment
region and all major axes of the one or more securing members are
generally located within a circular sector having an arc of 180
degrees or less; configuring the single-disc device in a delivery
configuration and advancing the single-disc device to a delivery
site in the vessel; and deploying the single-disc device at the
delivery site in the vessel.
28. The method according to claim 27, comprising: coupling the
single-disc device to a delivery catheter; inserting the
single-disc device and the delivery catheter into a delivery
sheath, wherein the frame element collapses as the single-disc
device is inserted into the delivery sheath, and wherein the frame
element expands as the single-disc device exits the delivery
sheath.
29. The method according to claim 28, wherein deploying the
single-disc device comprises advancing the single-disc device
through the delivery sheath, such that at least a portion of the
single-disc device exits the delivery sheath distal of the delivery
sheath.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This is a continuation-in-part of application Ser. No.
13/210,198, filed Aug. 15, 2011, which is a continuation-in-part of
application Ser. No. 12/400,445, filed Mar. 9, 2009, which claims
priority to U.S. Provisional Application Ser. No. 61/034,772, filed
Mar. 7, 2008, both of which are incorporated herein by reference in
their entireties.
FIELD OF THE INVENTION
[0002] The present invention is directed to a medical device and
particularly to a device for closing congenital cardiac defects.
The present invention is specifically directed to a heart occlusion
device with a self-centering mechanism.
DESCRIPTION OF THE PRIOR ART
[0003] Heart occlusion devices for correcting congenital heart
defects, such as atrial septal defects ("ASD"), patent foramen
ovale ("PFO") defects, ventricular septal defects ("VSD"), and
patent ductus arteriosus ("PDA") defects, are known to the medical
field. The following companies manufacture different types of
devices: AGA Medical, Microvena Corp./EV3 Medical, Velocimed/St.
Jude Medical, Occlutech International, NMT Medical, Cardia, Inc.,
Solysafe S A, Sideris (Custom Medical, Inc.), W L Gore, and Cook,
Inc.
[0004] A specific example of one such heart defect is a PFO. A PFO,
illustrated in FIG. 1 at 6A, is a persistent, one-way, usually
flap-like opening in the wall between the right atrium 2 and left
atrium 3 of the heart 1. Because left atrial (LA) pressure is
normally higher than right atrial (RA) pressure, the flap usually
stays closed. Under certain conditions, however, right atrial
pressure can exceed left atrial pressure, creating the possibility
that blood could pass from the right atrium 2 to the left atrium 3,
and blood clots could enter the systemic circulation. It is
desirable that this circumstance be eliminated.
[0005] The foramen ovale 6A serves a desired purpose when a fetus
is gestating in utero. Because blood is oxygenated through the
umbilical chord and not through the developing lungs, the
circulatory system of the fetal heart allows the blood to flow
through the foramen ovale as a physiologic conduit for
right-to-left shunting. After birth, with the establishment of
pulmonary circulation, the increased left atrial blood flow and
pressure results in functional closure of the foramen ovale. This
functional closure is subsequently followed by anatomical closure
of the two over-lapping layers of tissue: septum primum 8 and
septum secundum 9. However, a PFO has been shown to persist in a
number of adults.
[0006] The presence of a PFO defect is generally considered to have
no therapeutic consequence in otherwise healthy adults. Paradoxical
embolism via a PFO defect is considered in the diagnosis for
patients who have suffered a stroke or transient ischemic attack
(TIA) in the presence of a PFO and without another identified cause
of ischemic stroke. While there is currently no definitive proof of
a cause-effect relationship, many studies have confirmed a strong
association between the presence of a PFO defect and the risk for
paradoxical embolism or stroke. In addition, there is significant
evidence that patients with a PFO defect who have had a cerebral
vascular event are at increased risk for future, recurrent
cerebrovascular events.
[0007] Accordingly, patients at such an increased risk are
considered for prophylactic medical therapy to reduce the risk of a
recurrent embolic event. These patients are commonly treated with
oral anticoagulants, which potentially have adverse side effects,
such as hemorrhaging, hematoma, and interactions with a variety of
other drugs. The use of these drugs can alter a person's recovery
and necessitate adjustments in a person's daily living pattern.
[0008] In certain cases, such as when anticoagulation is
contraindicated, surgery may be necessary or desirable to close a
PFO defect. The surgery would typically include suturing a PFO
closed by attaching septum secundum to septum primum. This sutured
attachment can be accomplished using either an interrupted or a
continuous stitch and is a common way a surgeon shuts a PFO under
direct visualization.
[0009] Umbrella devices and a variety of other similar mechanical
closure devices, developed initially for percutaneous closure of
atrial septal defects (ASDs), have been used in some instances to
close PFOs. These devices potentially allow patients to avoid the
side effects often associated with anticoagulation therapies and
the risks of invasive surgery. However, umbrella devices and the
like that are designed for ASDs are not optimally suited for use as
PFO closure devices.
[0010] Currently available septal closure devices present
drawbacks, including technically complex implantation procedures.
Additionally, there are not insignificant complications due to
thrombus, fractures of the components, conduction system
disturbances, perforations of heart tissue, and residual leaks.
Many devices have high septal profile and include large masses of
foreign material, which may lead to unfavorable body adaptation of
a device. Given that ASD devices are designed to occlude holes,
many lack anatomic conformability to the flap-like anatomy of PFOs.
The flap-like opening of the PFO is complex, and devices with a
central post or devices that are self-centering may not close the
defect completely, an outcome that is highly desired when closing a
PFO defect. Hence, a device with a waist which can conform to the
defect will have much higher chance of completely closing the
defect. Even if an occlusive seal is formed, the device may be
deployed in the heart on an angle, leaving some components
insecurely seated against the septum and, thereby, risking thrombus
formation due to hemodynamic disturbances. Finally, some septal
closure devices are complex to manufacture, which may result in
inconsistent product performance.
[0011] Devices for occluding other heart defects, e.g., ASD, VSD,
PDA, also have drawbacks. For example, currently available devices
tend to be either self-centering or non-self-centering and may not
properly conform to the intra-cardiac anatomy. Both of these
characteristics have distinct advantages and disadvantages. The
non-self centering device may not close the defect completely and
may need to be over-sized significantly. This type of device is
usually not available for larger defects. Further, the
self-centering device, if not sized properly, may cause injury to
the heart.
[0012] Some have sharp edges, which may damage the heart causing
potentially clinical problems.
[0013] Some devices contain too much nitinol/metal, which may cause
untoward reaction in the patient and hence can be of concern for
implanting physicians and patients.
[0014] Some currently marketed devices have numerous model numbers
(several available sizes), making it difficult and uneconomical for
hospitals and markets to invest in starting a congenital and
structural heart interventional program.
[0015] The present invention is designed to address these and other
deficiencies of prior art aperture closure devices. Furthermore,
other desirable features and characteristics of the present
invention will become apparent from the subsequent detailed
description and the appended claims, taken in conjunction with the
accompanying drawings and this section.
SUMMARY OF THE INVENTION
[0016] This document provides implantable occlusion devices and
methods for occluding, for example, bodily apertures and channels.
Some embodiments include frame elements, such as shape-memory
wires, that are bent into patterns to form full and/or partial
discs. Some embodiments are asymmetrical and include a full disc
and a partial disc that are separated by a waist portion. Some
embodiments include membranous coverings on the frame elements to
enhance the occlusive properties of the device. Some embodiments
include a self-centering feature.
[0017] Accordingly, one innovative aspect of the subject matter
described in this specification may be embodied in a single-disc
device for occluding an aperture within a body of a patient. The
single-disc device comprises: an occluder region comprising a frame
element, the frame element comprising a plurality of wire portions,
the plurality of wire portions configured to form a disc at a first
end of the single-disc device, wherein the disc generally defines a
disc plane; an attachment region with an axis that extends
transversely to the disc plane, the attachment region comprising an
occluder region attachment end and a securing region attachment
end, the occluder region attachment end being connected to the
occluder region; and a securing region connected to the securing
region attachment end and at a second end of the single-disc
device, the securing region comprising one or more securing
members, wherein a major axis of each of the one or more securing
members extends transversely to the axis of the attachment region
and all major axes of the one or more securing members are
generally located within a circular sector having an arc of about
180 degrees or less.
[0018] In various implementations, the major axes of the securing
members may be spaced symmetrically within the circular sector
having an arc of about 180 degrees or less. The one or more
securing members may each comprise one or more wire loops or wire
prongs. The circular sector may have an arc of 150 degrees or less.
The major axis of each of the one or more securing members may
extend at an angle between 80 and 100 degrees with respect to the
axis of the attachment region. The securing region may comprise
three or more securing members. The disc plane may extend at an
angle between 0 to 5 degrees with respect to the major axis of at
least one of the one or more securing members. The disc plane may
extend at an angle between 5 to 15 degrees with respect to the
major axis of at least one of the one or more securing members. The
occluder region may comprise a membrane configured to inhibit
passage of blood, wherein the membrane covers at least a portion of
the disc. The membrane may comprise a fluoropolymer. The membrane
may comprise polytetrafluoroethylene. The membrane may comprise
expanded polytetrafluoroethylene. The occluder region may further
comprise an expandable balloon configured to restrict fluid flow
through the aperture. The occluder region may comprise at least one
anchor. The single-disc device may comprise one or more visual
indicators configured to identify the orientation of the securing
region. The disc plane may extend at an angle between 75 to 105
degrees with respect to the axis of the attachment region. The
first end may be at the proximal end of the single-disc device, and
the second end may be at the distal end of the single-disc
device.
[0019] Another innovative aspect of the subject matter described in
this specification may be embodied in a method of occluding a
cardiac defect. The method comprises: providing a single-disc
device; configuring the single-disc device in a delivery
configuration and advancing the single-disc device to a delivery
site; and deploying the single-disc device at the delivery site.
The single-disk device comprises: an occluder region comprising a
frame element, the frame element comprising a plurality of wire
portions, the plurality of wire portions configured to form a disc
at a first end of the single-disc device, wherein the disc
generally defines a disc plane; an attachment region with an axis
that extends transversely to the disc plane, the attachment region
comprising an occluder region attachment end and a securing region
attachment end, the occluder region attachment end being connected
to the occluder region; and a securing region connected to the
securing region attachment end and at a second end of the
single-disc device, the securing region comprising one or more
securing members, wherein a major axis of each of the one or more
securing members extends transversely to the axis of the attachment
region and all major axes of the one or more securing members are
generally located within a circular sector having an arc of 180
degrees or less.
[0020] In various implementations, the method may further comprise
coupling the single-disc device to a delivery catheter. The method
may further comprise inserting the single-disc device and the
delivery catheter into a delivery sheath. The frame element may
collapse as the single-disc device is inserted into the delivery
sheath. Deploying the single-disc device may comprise advancing the
single-disc device through the delivery sheath such that at least a
portion of the single-disc device exits the delivery sheath distal
of the delivery sheath. The frame element may expand as the
single-disc device exits the delivery sheath. Deploying the
single-disc device may comprise pulling the delivery sheath away
from the cardiac defect while maintaining a position of the
single-disc device. Deploying the single-disc device may
substantially occlude the cardiac defect.
[0021] Another innovative aspect of the subject matter described in
this specification may be embodied in a system for occluding an
aperture within a body of a patient. The system comprises: a
single-disc occluder device; a deployment wire releasably attached
to the first end of the single-disc device; a delivery catheter
comprising a sheath configured to contain the deployment wire and
the single-disc occluder device arranged in a delivery
configuration, the delivery catheter configured to advance the
single-disc device to a delivery site; and an actuator device
attached to a proximal end of the delivery catheter, the actuator
device being configured to remotely control deployment of the
single-disc device at the delivery site. The single-disc device
comprises: an occluder region comprising a frame element, the frame
element comprising a plurality of wire portions, the plurality of
wire portions configured to form a disc at a first end of the
single-disc device, wherein the disc generally defines a disc
plane; an attachment region with an axis that extends transversely
to the disc plane, the attachment region comprising an occluder
region attachment end and a securing region attachment end, the
occluder region attachment end being connected to the occluder
region; and a securing region connected to the securing region
attachment end and at a second end of the single-disc device, the
securing region comprising one or more securing members, wherein a
major axis of each of the one or more securing members extends
transversely to the axis of the attachment region and all major
axes of the one or more securing members are generally located
within a circular sector having an arc of 180 degrees or less.
[0022] Another innovative aspect of the subject matter described in
this specification may be embodied in a method of occluding a blood
vessel. The method comprises: providing a single-disc device;
configuring the single-disc device in a delivery configuration and
advancing the single-disc device to a delivery site in the vessel;
and deploying the single-disc device at the delivery site in the
vessel. The single-disc device comprises: an occluder region
comprising a frame element, the frame element comprising a
plurality of wire portions, the plurality of wire portions
configured to form a disc at a first end of the single-disc device,
wherein the disc generally defines a disc plane; an attachment
region with an axis that extends transversely to the disc plane,
the attachment region comprising an occluder region attachment end
and a securing region attachment end, the occluder region
attachment end being connected to the occluder region; and a
securing region connected to the securing region attachment end and
at a second end of the single-disc device, the securing region
comprising one or more securing members, wherein a major axis of
each of the one or more securing members extends transversely to
the axis of the attachment region and all major axes of the one or
more securing members are generally located within a circular
sector having an arc of 180 degrees or less.
[0023] In various implementations, the method may further comprise
coupling the single-disc device to a delivery catheter; inserting
the single-disc device and the delivery catheter into a delivery
sheath, wherein the frame element collapses as the single-disc
device is inserted into the delivery sheath, and wherein the frame
element expands as the single-disc device exits the delivery
sheath. Deploying the single-disc device may comprise advancing the
single-disc device through the delivery sheath, such that at least
a portion of the single-disc device exits the delivery sheath
distal of the delivery sheath.
[0024] The device of the present invention has many advantages:
[0025] Lower Profile: The occluder device of the present invention
has a lower profile than available devices. [0026] Conformable: The
device is flexible and conformable to the patient anatomy,
specifically the hole that is being closed. There are no sharp
edges. The device is soft and hence less traumatic to the atrial
tissue. [0027] Self-Centering on Demand: Because of the unique way
the two discs are connected, the device has self-centering
characteristics. The uniqueness of this device is in the
self-centering mechanism. In some embodiments, the waist of the
device is made of four wires. In some embodiments, the waist of the
device can be made of fewer than or more than four wires. The wires
will have the capability to conform to the shape and size of the
defect in the organ--a characteristic not seen in prior art
devices. Therefore, the self-centering of the device is dependent
upon the size and the shape of the defect. The wires will have
enough radial force to maintain the self-centering configuration
but will not be strong enough to press against the defect edges in
a manner that exacerbates the defect. The device is fully
repositionable and retrievable after deployment. [0028] Custom Fit:
The device has the further ability to be custom-fit within the
defect using, for example, balloon-expansion of the waist. Because
of the self-expanding nature of the waist, this will not be needed
in most cases. However, in some cases in which custom expansion is
needed (oval defects, tunnel defects), the waist size can be
increased to conform to the defect by the balloon catheter
expansion, or another suitable method. A balloon may be inserted
through a hollow screw attachment on the device's delivery hub and
delivery cable. The expansion will be possible before the release
of the device, which will increase the margin of safety. [0029]
Fewer Sizes: The expandable waist requires fewer sizes to close a
wider variety of differently-sized defects. Thus, a single device
may offer physicians the ability to implant devices in several
different sizes. [0030] The device will be less thrombogenic as the
discs will be covered with ePTFE. The ePTFE has been time-tested
and found to be least thrombogenic. There is the ability to close
defects up to 42 mm with very mild modifications. [0031] Security:
There will be the opportunity to remain tethered to the implanted
device before releasing it, which is an extra security feature.
Uses:
[0032] The device of the present invention should be appropriate
for an ASD (atrial septal defect), PFO (patent foramen ovale), VSD
(ventricular septal defect), and PDA (patent ductus arteriosus)
with minor modifications. One skilled in the art would also
recognize the device's application for use as a vascular occluder
or plug as well as an atrial appendage occluder.
[0033] An important use of the device will also be in closure of an
aperture in a left atrial appendage. The device can be modified to
conform to the atrial appendage anatomy. The discs are modified so
that the device is not extruded out with the heartbeats. Yet, the
device is still soft enough to form adequate closure.
[0034] The discs can also be modified so that they become
compatible for closure of veins and arteries. For this use, the
connecting waist will become equivalent (or near equivalent) to the
diameter of the discs. Other important uses will be in closure of
coronary artery fistulas, arteriovenous fistulas, arteriovenous
malformations, etc.
[0035] The objects and advantages of the invention will appear more
fully from the following detailed description of the preferred
embodiments of the invention made in conjunction with the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] FIG. 1 is a schematic representation of a human heart
including various septal defects.
[0037] FIG. 2 is a perspective view of the occluder device of the
present invention.
[0038] FIG. 3 is a top plan view of the occluder device of FIG.
2.
[0039] FIG. 4 is a side plan view of the occluder device taken
along lines in FIG. 2.
[0040] FIG. 5 is a side plan view of the occluder device taken
along in FIG. 2.
[0041] FIG. 6 is a perspective view of the occluder device of FIG.
2, illustrating the covering 42.
[0042] FIG. 7 is a top plan view of the occluder device of FIG.
6.
[0043] FIG. 8 is a perspective view of the occluder device first
emerging from the catheter.
[0044] FIG. 9 is a perspective view of the occluder device half-way
emerged from the catheter.
[0045] FIG. 10 is a perspective view of the occluder device fully
emerged from the catheter and separated from the deployment
cable.
[0046] FIG. 11 is a perspective view of the occluder device of the
present invention illustrating restriction wires encircling the
waist of the occluder device.
[0047] FIG. 12A is a perspective view of a first alternative
embodiment of the occluder device of the present invention.
[0048] FIG. 12B is a side plan view of the first alternative
embodiment of the occluder device of the present invention as shown
in FIG. 12A.
[0049] FIG. 13 is a side plan view of a second alternative
embodiment of the occluder device of the present invention.
[0050] FIG. 14 is a side plan view of a third alternative
embodiment of the occluder device of the present invention.
[0051] FIG. 15 is a side plan view of a fourth alternative
embodiment of the occluder device of the present invention.
[0052] FIG. 16 is a side view of another exemplary alternative
embodiment of the occluder device.
[0053] FIG. 17 is a side view of another exemplary alternative
embodiment of the occluder device.
[0054] FIG. 18 is a perspective view of another exemplary
alternative embodiment of the occluder device.
[0055] FIG. 19 is a plan view of another exemplary alternative
embodiment of the occluder device, depicted with reference to
planar quadrants in FIG. 19A.
[0056] FIG. 20 is a side view of another exemplary alternative
embodiment of the occluder device.
[0057] FIG. 21A is a perspective view of another exemplary
alternative embodiment of the occluder device.
[0058] FIG. 21B is a plan view of another exemplary alternative
embodiment of the occluder device.
[0059] FIG. 21C is a plan view of another exemplary alternative
embodiment of the occluder device.
[0060] FIG. 21D is a plan view of another exemplary alternative
embodiment of the occluder device.
[0061] FIG. 21E is a plan view of another exemplary alternative
embodiment of the occluder device.
[0062] FIG. 22 is a plan view of another exemplary alternative
embodiment of the occluder device.
[0063] FIGS. 23A and 23B are a flowchart of an exemplary embodiment
of a method for occluding an aperture defect in a heart to prevent
the flow of blood therethrough, and that may be implemented using
the occluder devices of FIGS. 2-22.
[0064] FIG. 24A is a schematic representation of a human heart
including a perimembranous ventricular septal defect.
[0065] FIG. 24B is the schematic representation of the human heart
of FIG. 24A including an exemplary asymmetrical occlusion
device.
[0066] FIG. 25 is a schematic side view representation of an
exemplary embodiment of an asymmetrical occlusion device.
[0067] FIG. 26 is a perspective view of an exemplary embodiment of
an asymmetrical occlusion device.
[0068] FIGS. 27A and 27B are schematic representations of two
exemplary embodiments of asymmetrical occlusion devices.
[0069] FIG. 28 is a schematic side view representation of another
exemplary embodiment of an asymmetrical occlusion device.
DETAILED DESCRIPTION OF THE INVENTION
[0070] The following detailed description is merely exemplary in
nature and is not intended to limit the disclosure or the
application and uses of the disclosure. Furthermore, there is no
intention to be bound by any theory presented in the preceding
background information or the following detailed description.
[0071] The present invention provides a device for occluding an
aperture within body tissue. One skilled in the art will recognize
that the device and methods of the present invention may be used to
treat other anatomical conditions in addition to those specifically
discussed herein. As such, the invention should not be considered
limited in applicability to any particular anatomical
condition.
[0072] FIG. 1 illustrates a human heart 1, having a right atrium 2,
a left atrium 3, a right ventricle 4, and a left ventricle 5. Shown
are various anatomical anomalies 6A, 6B, and 6C. The atrial septum
7 includes septum primum 8 and septum secundum 9. The anatomy of
the septum 7 varies widely within the population. In some people,
the septum primum 8 extends to and overlaps with the septum
secundum 9. The septum primum 8 may be quite thin. When a PFO is
present, blood could travel through the passage 6A between septum
primum 8 and septum secundum 9 (referred to as "the PFO tunnel").
Additionally or alternatively, the presence of an ASD could permit
blood to travel through an aperture in the septal tissue, such as
that schematically illustrated by aperture 6B. A VSD is similar to
an ASD, except that an aperture 6C exists in the septum between the
left and right ventricle of the heart.
[0073] PDA results from defects in the ductus arteriosus. The human
blood circulation comprises a systemic circuit and a pulmonary
circuit. In the embryonic phase of human development, the two
circuits are joined to one another by the ductus arteriosus. The
ductus connects the aorta (circulation to the body) to the
pulmonary artery (pulmonary circuit). In normal development of an
infant, this ductus closes after birth. If development is
defective, it can happen that the ductus does not close, and as a
result the two blood circuits are still joined even after
birth.
[0074] Unless specifically described otherwise, "aperture" 6 will
refer to the specific heart defects described above, including PFO
6A, ASD 6B, VSD 6C, perimembranous VSD 6D, and PDA among
others.
[0075] As used herein, "distal" refers to the direction away from a
catheter insertion location and "proximal" refers to the direction
nearer the insertion location.
[0076] As used herein, "left" refers to the left chambers of the
heart, including the left atrium and left ventricle. "Right" refers
to the right chambers of the heart, including the right atrium and
right ventricle.
[0077] As used herein, "superior" refers to the direction toward
the head of the patient and "inferior" refers to the direction
toward the feet of the patient.
[0078] As used herein, "memory" or "shape memory" refers to a
property of materials to resume and maintain an intended shape
despite being distorted for periods of time, such as during storage
or during the process of delivery in vivo.
[0079] Referring now to FIGS. 2-5, the occluder device 10 of the
present invention comprises two separate uniquely shaped memory
wires 12, 14. The wire can be formed of biocompatible metals or
polymers, such as bioresorbable polymers, shape memory polymers,
shape memory metal alloys, biocompatible metals, bioresorbable
metals, or combinations thereof. Specific examples include but are
not limited to iron, magnesium, stainless steel, nitinol, or
combinations of these and similar materials. A preferred metal for
the present invention is a nitinol alloy. Nitinol (an acronym for
Nickel Titanium Naval Ordnance Laboratory) is a family of
intermetallic materials, which contain a nearly equal mixture of
nickel (55 wt. %) and titanium. Other elements can be added to
adjust or "tune" the material properties. Nitinol exhibits unique
behavior, specifically, a well defined "shape memory" and super
elasticity. In general, any biocompatible material with a memory
capability can be used with the present invention. The thermal
shape memory and/or superelastic properties of shape memory
polymers and alloys permit the occluder 10 to resume and maintain
its intended shape in vivo despite being distorted during the
delivery process. In certain embodiments, the memory may also
assist in pressing an aperture, such as a PFO tunnel, closed. The
diameter or thickness of the wire depends on the size and type of
the device, i.e., the larger the device, the larger the diameter of
the wire. In general, wire having a diameter between about 0.2 mm
and 0.8 mm can be used. As described further below in connection
with FIGS. 12A, 12B, and 22, in certain embodiments more than two
wires may be utilized.
[0080] The first wire 12 forms one or more first geometric forms
12A and one or more second geometric forms 12B. "Geometric forms"
as used herein comprises symmetric as well as asymmetric forms.
Relative to a delivery attachment mechanism or hub 30, discussed
below in greater detail, the first geometric form 12A of the first
wire 12 preferably comprises a distal geometric form, and the one
or more second geometric forms 12B of the first wire preferably
each comprise proximal geometric forms. In the embodiment of FIGS.
2-5, there is a single first, or distal, geometric form 12A of the
first wire 12. Also in the embodiment of FIGS. 2-5, there are two
second, or proximal, geometric forms 12B of the first wire 12
(namely, 12B(A) and 12B(B)). However, the number and configuration
of the first and/or second geometric forms 12A, 12B of the first
wire 12 may vary.
[0081] Similarly, the second wire 14 forms a first geometric form
14A and a second geometric form 14B. Relative to the hub 30, the
first geometric form 14A of the second wire 14 preferably comprises
a distal geometric form, and the second geometric form 14B of the
second wire preferably comprises a proximal geometric form. In the
embodiment of FIGS. 2-5, there is a single first, or distal,
geometric form 14A of the second wire 14. Also in the embodiment of
FIGS. 2-5, there are two second, or proximal, geometric forms 14B
of the second wire 14 (namely, 14B(A) and 14B(B)). However, the
number and configuration of the first and/or second geometric forms
14A, 14B of the second wire 14 may vary.
[0082] The first geometric forms 12A of the first wire 12 and the
first geometric forms 14A of the second wire 14 form a first plate,
such as a disc, or another otherwise relatively flat surface
(hereinafter referred to as a "plate") 16 in a first plane 218. The
second geometric forms 12B of the first wire 12 and the second
geometric forms 14B of the second wire 14 form a second plate 18
(also referred to as a "disc" in certain embodiments) in a second
plane 220 that is parallel to and remote from the first plane 218.
In the embodiment of FIGS. 2-5, the first and second plates 16, 18
each comprise one or more semi-circular discs (as described
directly below). However, this may vary in some embodiments, for
example as described further below in connection with FIGS.
21A-21E.
[0083] As shown in FIGS. 2-5, in these embodiments, each wire 12 or
14 forms a shape which mirrors that of the respective wire 14 or
12. Specifically, each wire 12, 14 forms a distal semi-circle or
half-disc 12A, 14A in addition to two proximal quarter-circles or
quarter-discs 12B, 12B' or 14B, 14B'. The two proximal
quarter-circles of each wire together form proximal semi-circles or
half-discs 12B, 12B' or 14B, 14B'. The two distal semi-circles of
each respective wire 12A, 14A together comprise a distal circle or
distal disc 16 of the occluder 10. The four proximal
quarter-circles 12B, 12B', 14B, 14B', which form a "four-leaf
clover" configuration, comprise a proximal circle or proximal disc
18 of the occluder 10.
[0084] The proximal semi-circle 12B, 12B' or 14B, 14B' of each wire
is connected to the distal semi-circle 12A or 14A by waist portions
(also referred to herein as waist components) 12C, 14C. As shown in
FIG. 2, there are two waist portions 12C, 14C per wire. The four
waist portions (two from each wire) 12C, 14C together comprise a
restricted area or waist 20 of the occluder device 10. The distance
between the waist portions, both within the same wire and from wire
to wire, determines the size of the waist 20. The size of the waist
20 is dependent on the particular application and the size of the
occluder device 10. The resiliency and memory of the waist portions
12C, 14C and capacity to expand radially serves as a self-centering
mechanism of the occluder device 10 in apertures 6.
The Hub 30:
[0085] The two half-discs are not attached or joined to each other
except at the junction of the delivery attachment mechanism or hub
30. The ends 12D, 14D of wires 12, 14 will be welded or otherwise
connected to the hub 30.
Coverings 24A and 24B:
[0086] According to some embodiments of the present invention, the
distal disc 16 and/or proximal disc 18 may include membranous
coverings 24A and 24B, illustrated in FIGS. 6 and 7. The membranous
coverings 24A and 24B ensure more complete coverage of aperture 6
and promote encapsulation and endothelialization of tissue, thereby
further encouraging anatomical closure of the tissue and improving
closure rate. The coverings 24A and 24B also help stabilize the
occluder device 10.
[0087] The membranous coverings 24A and 24B may be formed of any
flexible, biocompatible material capable of promoting tissue growth
and/or act as a sealant, including but not limited to DACRON.RTM.,
polyester fabrics, Teflon-based materials, ePTFE, polyurethanes,
metallic materials, polyvinyl alcohol (PVA), extracellular matrix
(ECM) or other bioengineered materials, synthetic bioabsorbable
polymeric materials, other natural materials (e.g. collagen), or
combinations of the foregoing materials. For example, the
membranous coverings 24A and 24B may be formed of a thin metallic
film or foil, e.g. a nitinol film or foil, as described in U.S.
Pat. No. 7,335,426 (the entirety of which is incorporated herein by
reference). The preferred material is Poly(tetrafluoroethene)
(ePTFE), as it combines several important features such as
thickness and the ability to stretch. Loops may also be stitched to
the membranous coverings 24A and 24B to securely fasten the
coverings to occluder 10. The coverings may alternatively be glued,
welded or otherwise attached to the occluder 10 via the wires 12,
14.
Size:
[0088] As illustrated in FIGS. 2-7, the diameters of the distal
disc 16 and proximal disc 18 are generally 5-8 mm larger than the
diameter of the connecting waist 20. For example, if the diameter
of the connecting waist 20 is 4 mm, the diameters of the discs
16,18 are generally about 9 mm each. Because of the flexibility in
the waist 20, a 12 mm waist device will be able to be placed in a 6
mm to 12 mm defect. For larger waists 20 or larger devices, the
diameter of the disc size will increase proportionately.
[0089] It is within the scope of the present invention to envision
occluder devices available in 7 or more sizes, specifically waist
size having the following diameters for different-sized apertures
6: 6 mm, 12 mm, 18 mm, 24 mm, 30 mm, 36 mm, and 42 mm. Occluder
devices having waist size to fit other aperture sizes are also
contemplated.
Operation:
[0090] In general, the occluder 10 may be inserted into an aperture
6 to prevent the flow of blood therethrough. As a non-limiting
example, the occluder 10 may extend through a PFO 6A or an ASD 6B
such that the distal disc 16 is located in the left atrium 3 and
the proximal disc 18 is located in the right atrium 2 (as shown in
the heart 1 in FIG. 1). The closure of apertures in these and other
tissues, as well as other types of apertures, will become apparent
as described below.
[0091] Referring now to FIGS. 8-10, the occluder device 10 is
attached to a deployment cable 34 which is removably attached to
the occluder device 10 at the hub 30. As illustrated in FIG. 10,
one method of releasably attaching the deployment cable 34 to the
hub 30 is by threaded engagement utilizing a screw end 36 which
engages unseen female threads within the hub 30. Other known means
of attachment can be used to releasably connect the deployment
cable 34 to the hub 30.
[0092] When the deployment cable 34 is engaged with the hub 30, as
illustrated in FIGS. 8 and 9, the occluder device 10 is initially
housed within a flexible delivery catheter 40 having an open
channel 42. Reference is made to FIG. 8 which illustrates the
occluder device 10 in which the distal disc 16 is expanded, due to
the memory expansion of the wires 12 and 14, and housed within the
open channel 42 of the delivery catheter 40. During the initial
stages of placement of the occluder device 10, both the distal disc
16 and proximal disc 18, as well as the coverings 24A and 24B, are
housed within the open channel 42 of the delivery catheter 40. In
this manner, the catheter 40 is fed into the blood vessel through
an already placed sheath and advanced via the blood vessel system
to a defect in the heart.
[0093] Once the delivery catheter 40 traverses the aperture that
needs to be occluded, e.g., a hole in the heart, the device 10 will
be partially advanced from the catheter 40 as illustrated in FIG.
8. As the device 10 leaves the catheter 40, the distal disc 16,
which includes the covering 24A, begins to expand on the distal
side of the aperture. Due to the memory capabilities of the wires
12 and 14, the occluder device 10 begins to return to its normal
shape such that the distal disc 16 expands on the distal side of
the aperture in the heart. Once the distal disc 16 is completely
out of the catheter opening 42, as shown in FIG. 9, it 16 and the
attached covering 24A become fully expanded. The catheter 40 is
further withdrawn to expose the waist 20 which then begins to
emerge and expand due to the memory shape of the wires 12 and 14.
Advantageously, the waist 20 is designed to expand such that each
of the wires forming the waist 20 are urged against the aperture in
the heart causing a custom fit device of the occluder 10 within the
aperture. As the catheter 40 is further withdrawn, the proximal
disc 18 and the covering 24B begin their process of expansion on
the proximal side of the aperture. When the proximal disc 18 is
fully delivered from the catheter 40, it will expand and
effectively form a seal over the aperture. The distal disc 16 and
proximal disc 18 are secured in place by the action of the wires in
the waist 20 urging against the aperture. At this stage, as shown
in FIG. 10, the deployment cable 34 is removed from the hub 30 and
the catheter 40 and the deployment cable 34 are removed from the
body. The occluder device 10 is left in the heart at the region of
the aperture. Over several months, cardiac tissue and other
membranous structures will bind to the occluder device 10 thereby
permanently locking the occluder device 10 to the specific area in
the heart.
[0094] The two wires 12, 14 function to form round discs 16, 18 on
each side of the tissue. The discs 16, 18 maintain the circular
shape because of the memory capability of the wires 12, 14. The
coverings 24A, 24B will stabilize the discs and will act to
completely occlude the defect.
[0095] The wires 12, 14 at the waist portions 12C, 14C will be
separated enough at the waist 20 to make the occluder device 10
self-centering. Due to the conformity of this design, the occluder
device 10 can self-center within commonly (round, oval) shaped
septal defects, as the waist 20 can adjust to any type of
opening.
[0096] If a larger-diameter waist 20 is required, the waist 20 has
the capability to expand (only if needed) to a larger size with the
help of a balloon. In this manner, a center channel 50 extends
through the deployment cable 34, the hub 30, and the screw end 36.
A balloon (not shown) is urged through the center channel 50 after
the occluder device has been removed from the catheter 40 and
expanded, and preferably before the hub 30 has been attached from
the deployment cable 34. The balloon is placed within the waist 20
and expanded. The waist 20 is dilatable, i.e., expandable, when
gentle pressure of the balloon is applied. The dilation will expand
the waist portions 12C, 14C. Once the desired diameter is reached,
the balloon is deflated and removed by withdrawal through the
center channel 50. Once the occluder device 10 appears stable, the
device 10 is separated from the deployment cable 34 as discussed
above. In the majority of cases, balloon dilation will not be
required.
Restriction Wires 60, 62 (FIG. 11):
[0097] In order to increase stability in the occluder device 10 and
to avoid significant crimping of the waist 20 or the proximal or
distal discs 18, 16, the waist 20 can be encircled by one or more
restriction wires 60, 62 as illustrated in FIG. 11. The restriction
wires 60, 62 can be made of the same wire material as the wires 12
and 14, or they may be of a different material, such as plastic
wire, fish line, etc. The restriction wires 60, 62 may be welded or
otherwise connected to the waist portions 12C, 14C. The purpose of
the restriction wires 60 or 62 is also to restrict the
circumference of the waist 20 if necessary. Although one
restriction wire 60 is generally suitable, a second restriction
wire 62 can also be incorporated to further improve stability.
ALTERNATIVE EMBODIMENTS
[0098] Reference is now made to FIGS. 12-15 for alternative
embodiments of the occluder device 10 of the present invention.
Unless otherwise noted, the same reference numbers will be applied
to similar structures in each embodiment.
[0099] Reference is made to FIGS. 12A and 12B for an alternative
embodiment of the occluder device (labeled as occluder device 100
in FIGS. 12A and 12B). The occluder device 100 in this embodiment
is designed for PDA procedures. This embodiment is similar to
previously described embodiments except that it is comprised of
four wires 112, 114, 116, 118 rather than two wires. In this case,
each wire forms a mirror image of each of its neighboring wires.
For example, wire 112 mirrors wire 114 as well as wire 118, etc.
Each of the four wires 112, 114, 116, 118 forms a proximal
quarter-disc 112B, 114B, 116B, 118B and a distal quarter-disc 112A,
114A, 116A, 118A. The proximal quarter-discs 112B, 114B, 116B, 118B
together form a proximal disc 111 in a "four-leaf clover"
configuration, and the distal quarter-discs 112A, 114A, 116A, 118A
together form a distal disc 110 also in a "four-leaf clover"
configuration. This embodiment also differs from
previously-described embodiments in that the waist 20 is comprised
of a single portion of each of the four wires 112, 114, 116, 118.
This embodiment further differs from previously-described
embodiments in that it comprises a second hub 119 with a screw
mechanism. The second hub 119 connects to the distal disc 110 by
distal ends 112E, 114E (116E, 118E behind 112E, 114E in FIG. 12B)
of each of the four wires 112, 114, 116, 118, just as proximal ends
112D, 114D (116D, 118D behind 112D, 114D in FIG. 12B) connect to
the proximal hub 30. The wires 112, 114, 116, 118 may be connected
to the hubs 30, 119 by welding or other means known in the art. The
length of the waist 20 will be anywhere from 4-8 mm. In addition,
the distal disc 110 is typically 4-8 mm larger than the waist 20.
However, the proximal disc 111 is generally 1-3 mm, preferably 2
mm, larger than the waist 20 diameter. Hence, the diameter of the
distal disc 110 is larger than the diameter of the proximal disc
111.
[0100] Reference is now made to FIG. 13 for a second alternative
embodiment of the occluder device 120. This embodiment, like the
embodiment shown in FIGS. 12A and 12B, uses four wires 112, 114,
116, 118 and two hubs 30, 119. It is designed to close apertures in
large arteries and veins. In occluder device 120, the distal and
proximal discs 122 and 124 are modified so that they are compatible
with closure of veins and arteries. For this use, the connecting
waist 20 is equivalent or near equivalent to the diameter of each
of the discs 122, 124. The diameter of the waist 20 will be 1 mm
smaller than the discs 122, 124. The length of the waist will be
4-8 mm. This embodiment can be used in the closure of coronary
artery fistulas, arteriovenous fistulas, and arteriovenous
malformations.
[0101] Reference is made to FIG. 14 for a third alternative
embodiment of the occluder device 130. The importance of the
occluder device 130 will be in the closure of the left atrial
appendage. The device 130 is modified to conform to the atrial
appendage anatomy. The distal disc 132 is modified so that the
device 130 is not extruded out with the heartbeats. For the left
atrial appendage occluder device 130, the memory wire structure of
the distal disc 132 is woven to form anywhere from 2 to 8
protuberances or hooks 136. Upon inserting the device 10 in an
aperture in the left atrial appendage of the heart, the hooks 136
grip the outer portion of the left atrium heart tissue and thereby
assist in keeping the device 130 from extruding out of the left
atrial appendage with contraction of the heart. The proximal disc
134 is typically flat and similar to the disc formed by the
proximal discs 18 in FIGS. 2-7. The proximal disc 134 abuts the
inner atrial wall of the heart. Typically, the waist 20 will be
about 4-8 mm in diameter. The length of the waist may range from 4
to 16 mm.
[0102] Reference is made to FIG. 15 for a fourth alternative
embodiment of the occluder device 140. Occluder device 140 is
intended to occlude perimembranous ventricular septal ("PVS")
defects. This embodiment, like the embodiment shown in FIGS. 12A
and 12B, uses four wires 112, 114, 116, 118 and two hubs 30, 119.
The occluder device 140 is different from some embodiments in that
two of the four wires form truncated distal-quarter discs, with the
effect that the distal disc 142 substantially misses half of the
disc. Therefore, the device 140 has approximately 1.5 discs as
opposed to two discs. The half distal disc 142 is also
significantly longer than the proximal disc 144. Typically, the
distal disc 142 will be 6-8 mm in diameter. In addition, the distal
disc 142 converges or curves inwards at 143, i.e., it is angled to
contact the ventricular septum when the device 140 is inserted in
the PVS defect. (See below for details.) The lower edge of the
proximal disc (opposite to the long distal disc) will be 3-4 mm
larger than the waist, and the other half of the proximal disc will
be 2-3 mm larger than the waist. The discs can also be modified to
be of different shapes in the same device. Alternatively, the disc
angle may be created by a straight distal disc 142 angled with
respect to the plane perpendicular to the waist 20 in a slant
fashion.
[0103] With reference to FIGS. 16-22, various additional exemplary
alternative embodiments are provided with respect to the occluder
device and/or components thereof. With reference to FIG. 16,
certain embodiments of the occluder device 10 may have one or more
plates 16, 18 and/or geometric forms 12A, 12B, 14A, 14B of
different sizes and/or configurations as compared with the
embodiment described above in connection with FIG. 2. For example,
the distal (or first) plate 16 and the proximal (or second) plate
18 may be offset with respect to the hub 30, and/or one side of a
plate 16, 18 may be relatively higher or farther from the hub 30
than the other, for example via an oblique shift. In the particular
embodiment of FIG. 16, a center 202 of the hub 30 is not aligned
with (and, rather, is offset against) a center 204 of the first
plate 16, but is aligned with a center 206 of the second plate 18.
In another embodiment, the distal plate 16 and the proximal plate
18 are of equal size, yet off set from each other via a shift in
opposite directions from the hub.
[0104] In certain embodiments, the first and second plates 16, 18
are configured such that a first segment formed from a first
portion of the first wire 12 (for example, corresponding to form
12B of FIG. 16) has a first length, a second segment formed from a
first portion of the second wire 14 (for example, corresponding to
form 14A of FIG. 16) has a second length, a third segment formed
for a second portion of the first wire 12 (for example,
corresponding to form 12A of FIG. 16) has a third length, and a
fourth segment formed for a second portion of the second wire 14
(for example, corresponding to form 14B of FIG. 16) has a fourth
length. The second length is substantially equal to the first
length. The third length is greater than the first length. The
fourth length is substantially equal to the third length.
[0105] The semi-circle or half-disc 12A of the first wire 12 (also
referenced above as the first geometric form 12A of the first wire
12) may differ in size (for example, having a larger radius and
therefore a larger surface area) from the semi-circle or half-disc
14A of the second wire 14 (also referenced above as the first
geometric form 14A of the second wire 14). In certain other
embodiments, the semi-circle or half-disc 12A of the first wire 12
and the semi-circle or half-disc 14A of the second wire 14 may be
of the same size same as one another, but may collectively form a
distal plate 16 that differs in size from the proximal plate 18. In
one such embodiment, the distal plate 16 is smaller in surface area
than the proximal plate 18.
[0106] For example, the distal plate 16 may be of the same size as
in FIG. 2, while the proximal plate 18 is larger in surface area
than depicted in FIG. 2. This may occur, by way of example, when
certain of the proximal quarter-circles of the second geometric
forms 12B, 14B are larger in surface area than depicted in FIG. 2.
Certain proximal quarter-circles of the second geometric forms 12B,
14B may be larger in surface area than other, adjacent
quarter-circles of the second geometric forms 12B, 14B. Such
differing sizes of the proximal quarter-circles of the second
geometric forms 12B, 14B may be present regardless of the relative
sizes of the distal and proximal plates 16, 18.
[0107] FIG. 17 depicts an embodiment of an occluder device
contemplated herein with a wider waist 20. In one exemplary
embodiment, the first plate 16 and the second plate 18 are disposed
further apart as compared with the example of FIG. 2, so that a
total length 225 of the waist 20 is greater than eight millimeters.
Preferably, in this embodiment, the length 225 of the waist 20 is
greater than eight millimeters and less than or equal to ten
millimeters. In one such example, a straight-line distance between
the first plane 218 and the second plane 220 of FIG. 2 is greater
than eight millimeters, and is preferably also less than or equal
to ten millimeters.
[0108] FIG. 18 depicts an embodiment of an occluder device
contemplated herein with a hook engagement system 230. The hook
engagement system 230 comprises a hook 232 and a lanyard 234
coupled thereto. The hook 232 is connected to the first plate 16 or
the second plate 18 (and to the first and/or second wires 12, 14
thereof) described above, preferably proximate one of the coverings
24A, 24B. The hook engagement system 230 is configured for
engagement with a positioning system (not depicted). In one
embodiment, the hook engagement system 230 is used to remove the
occluder device 10 from the heart. In this regard, a loop of the
lanyard 234 is positioned onto the hook 232, and the lanyard 234 is
pulled in the direction away from the heart, thus pulling the
occluder device 10 through the heart aperture and through the body.
In another embodiment, the positioning system comprises a
deployment system for deploying the occluder device 10, for example
by grasping the hook 232 for movement of the occluder device 10
into a human heart in a desired position proximate an aperture. In
a further embodiment, the positioning system comprises a
repositioning system for repositioning the occluder device 10, for
example by grasping the hook 232 for adjusting the position of the
occluder device 10 for more ideal placement of the occluder device
10 proximate an aperture. In certain embodiments, the lanyard
(and/or another connection feature) is part of the positioning
system, and the hook may exist separately from the occluder device
10. The hook 232 is preferably used in connection with a screw
device for further engagement with the positioning system, such as
a screw and nut system used in conjunction with FIGS. 8-10
described above. For example, the hook 232 may be positioned
internal to a screw and nut system during placement of the device.
Alternatively, the hook 232 may be used in connection with a thread
cord through an eyelet or an opening, so that the cord would need
to be pulled in order to lose the connection with the occluder
device 10. In addition, such a cord may be used for retrieval of
the occluder device 10, for example by including multiple lumens,
preferably with an opening or slit, as part of a catheter delivery
system. Other engagement and positioning systems are also
contemplated, e.g., detent pin/receptacle, clasp/ball,
clasp/eyelet, and the like.
[0109] With reference to FIGS. 19 and 19A, an embodiment of an
occluder device contemplated herein is depicted with overlapping
wires at least at one plate. Overlapping wires add additional
strength and rigidity to the plate of the occluder device.
Specifically, the first geometric form 12A of the first wire 12
overlaps at least a portion of one region (for example, at least a
portion of a common spatial quadrant, half-plane, and/or quartile)
in common with the first geometric form 14A of the second wire 14
within the first plate 16. Alternatively, or in addition, the
second geometric form 12B (not shown) of the first wire 12 overlaps
at least a portion of one region (for example, at least a portion
of a common spatial quadrant, half-plane, and/or quartile) in
common with the second geometric form 14B (not shown) of the second
wire 14 within the second plate 18 (not shown).
[0110] In a preferred embodiment, as illustrated in FIG. 19, the
first geometric form 12A of the first wire 12 occupies at least
three spatial quadrants 300, 301, and 302, two of which (namely,
spatial quadrants 300 and 302) are shared in their entireties with
the first geometric form 14A of the second wire 14. Likewise, the
first geometric form 14A of the second wire 14 occupies at least
three spatial quadrants 302, 303, and 300, two of which (namely,
spatial quadrants 300 and 302) are shared in their entireties with
the first geometric form 12A of the first wire 12. Similarly, the
second geometric form 12B of the first wire 12 (not depicted in
FIG. 19) occupies at least three spatial quadrants, two of which
are shared in their entireties with the second geometric form 14B
of the second wire 14 (not depicted in FIG. 19). Likewise, the
second geometric form 14B of the second wire 14 occupies at least
three spatial quadrants, two of which are shared in their
entireties with the second geometric form 12B of the first wire
12.
[0111] FIG. 19A depicts an exemplary classification of planar
quadrants for the first and second planes 218, 220 of FIG. 2 for
reference with respect to the embodiment of FIG. 19. One skilled in
the art will recognize that less or more than four quadrants can be
utilized. With reference to FIG. 19A, the first plane 218 of FIG. 2
has a first quadrant 241(A), a second quadrant 242(A) that is
adjacent to the first quadrant 241(A), a third quadrant 243(A) that
is below the first quadrant 241(A), and a fourth quadrant 244(A)
that is below the second quadrant 242(A) and adjacent to the third
quadrant 243(A). The second plane 220 of FIG. 2 has a first
quadrant 241(B), a second quadrant 242(B) that is adjacent to the
first quadrant 241(B), a third quadrant 243(B) that is below the
first quadrant 241(B), and a fourth quadrant 244(B) that is below
the second quadrant 242 (B) and adjacent to the third quadrant
243(B). The first quadrant 241(A) of the first plane 218 is closer
to the first quadrant 241(B) of the second plane 220 than to the
second, third, or fourth quadrants 242(B), 243(B), 244(B) of the
second plane 220. The second quadrant 242(A) of the first plane 218
is closer to the second quadrant 242(B) of the second plane 220
than to the first, third, or fourth quadrants 241(B), 243(B),
244(B) of the second plane 220. The third quadrant 243(A) of the
first plane 218 is closer to the third quadrant 243(B) of the
second plane 220 than to the first, second, or fourth quadrants
241(B), 242(B), 244(B) of the second plane 220. The fourth quadrant
244(A) of the first plane 218 is closer to the fourth quadrant
244(B) of the second plane 220 than to the first, second, or third
quadrants 241(B), 242(B), 243(B) of the second plane 220.
[0112] With reference to the spatial quadrants set forth in FIG.
19A, in one preferred embodiment of FIG. 19, the first geometric
form 12A of the first wire 12 extends through the first, second,
and third quadrants 241(A), 242(A), 243(A) of the first plane 218.
The first geometric form 14A of the second wire 14 extends through
the first, third, and fourth quadrants 241(A), 243(A), and 244(A)
of the first plane 218. Accordingly, in this embodiment, the first
geometric forms 12A, 14A of the first and second wires 12, 14 share
the first and third quadrants 241(A), 243(A) of the first plane 218
in common, for example to provide increased support and/or rigidity
for the occluder device 10.
[0113] Also in one version of this embodiment of FIG. 19, the
second geometric form 12B of the first wire 12 extends through the
first, second, and third quadrants 241(B), 242(B), 243(B) of the
second plane 220. The second geometric form 14B of the second wire
14 extends through the first, third, and fourth quadrants 241(B),
243(B), 244(B) of the second plane 220. Accordingly, in this
version, the second geometric forms 12A, 14A of the first and
second wires 12, 14 share the first and third quadrants 241(B),
243(B) of the second plane 220 in common, for example to provide
increased support and/or rigidity for the occluder device 10.
[0114] However, this may vary in other versions or embodiments. For
example, in another version of the embodiment depicted in FIG. 19,
the second geometric form 12B of the first wire 12 extends through
the third, fourth, and first quadrants 243(B), 244(B), 241(B) of
the second plane 220, and the second geometric form 14B of the
second wire 14 extends through the first, second, and third
quadrants 241(B), 242(B), 243(B) of the second plane 220.
[0115] FIG. 20 depicts an embodiment of an occluder device
contemplated herein with a clothes-pin shape. In the embodiment of
FIG. 20, the first plate 16 and the second plate 18 described above
are non-parallel, and form a non-zero angle 260 with respect to one
another. The angle 260 is preferably greater than five degrees, is
more preferably greater than ten degrees, and is most preferably
approximately equal to twenty degrees.
[0116] Also in the embodiment of FIG. 20, the waist 20 is
configured such that the above-referenced waist components 12C of
the first wire 12 and the waist components 14C of the second wire
14 are unequal in size. For example, as shown in FIG. 20, each
waist component 12C of the first wire 12 has a first length
indicated by double arrow 261, and each waist component 14C of the
second wire 14 has a second length indicated by double arrow 262
that is greater than the first length. The length is defined as the
distance between the first plate 16 and the second plate 18 taken
from a predetermined distance from the occluder device 10's center
point. Each waist component 14C of the second wire 14 may also have
a greater surface area and radius as compared to respective waist
components 12C of the first wire 12. In addition, in the embodiment
of FIG. 20, the waist components 12C of the first wire 12 and the
waist components 14C of the second wire 14 are preferably
configured such that the waist 20 is curved, with a non-zero angle
of curvature. The angle of curvature of the waist 20 is preferably
greater than five degrees, is more preferably greater than ten
degrees, and is most preferably greater than twenty degrees.
[0117] FIGS. 21A-21E depict an embodiment of an occluder device
contemplated herein in which one or more of the first and second
plates 16, 18 are non-circular in their geometric shape(s). In one
embodiment of FIG. 21A, at least the first plate 16 has a generally
oval shape. In an embodiment of FIG. 21B, at least the first plate
16 has a generally rectangular shape. In an embodiment of FIG. 21C,
at least the first plate 16 has a generally triangular shape. In an
embodiment of FIG. 21D, at least the first plate 16 has a generally
elliptical shape. In an embodiment of FIG. 21E, at least the first
plate 16 has a generally keyhole shape. In certain versions, the
first plate 16 and/or the second plate 18 have generally the same
geometric shapes as one another. In certain other versions, the
first plate 16 and/or the second plate 18 differ from one another.
The first plate 16 and the second plate 18 may also comprise any
number of other different geometric shapes.
[0118] FIG. 22 depicts an embodiment of an occluder device
contemplated herein that is formed by more than two wires.
Specifically, in the embodiment of FIG. 22, the occluder device 10
has three wires, namely: the first wire 12 and the second wire 14
described above, as well as a third wire 205. In some embodiments,
four wires may be utilized. In some embodiments, six wires may be
utilized. In some embodiments, the number of wires may differ
further.
[0119] In the particular embodiment of FIG. 22, the three wires 12,
14, and 205 each form respective, non-overlapping thirds of each
plane. Specifically, as depicted in FIG. 22, the first geometric
form 12A of the first wire 12 is disposed within and extends
through a first region 272 of the first plane 218 described above.
The second geometric form 12B of the second wire 14 is disposed
within and extends through a second region 274 of the first plane
218. A first geometric form 207 of the third wire 205 is disposed
within and extends through a third region 276 of the first plane
218. The first geometric forms 12A, 14A, 207 of the first, second,
and third wires 12, 14, 205 collectively form the first plate
16.
[0120] Within the first plane 218, the first region 272 is adjacent
to the second region 274, with a common border 277 formed by the
first and second wires 12, 14. The first region 272 is also
adjacent to the third region 276, with a common border 278 formed
by the first and third wires 12, 205. In addition, the third region
276 is also adjacent to the second region 274, with a common border
279 formed by the second and third wires 14, 205.
[0121] Similarly, the second geometric form 12B of the first wire
12, the second geometric form 14B of the second wire 14, and a
second geometric form of the third wire 205 would likewise be
disposed within and extend through three similar adjacent,
non-overlapping regions of the second plane 220, collectively
forming the second plate 18 (not depicted in FIG. 22). The various
first and second components of the first, second, and third wires
12, 14, and 205 are preferably curved with an arch, such as is
shown in FIG. 22. Similar combinations of any number of different
amounts of wires can similarly be used to form any number of
different forms.
[0122] As mentioned above, in certain embodiments, the occluder
device 10 may include multiple hubs 30, for example as depicted in
FIG. 15. The number and configuration of such multiple hubs 30 may
vary in different embodiments. In one such embodiment, a first end
of the first wire 12 is disposed at a first hub 30, and at least
one of the second end of the first wire 12, the first end of the
second wire 14, and/or the second end of the second wire 14 is
disposed at a second hub (such as hub 119 of FIGS. 12B, 13, and/or
15). In one such exemplary embodiment, the first and second ends of
the first wire 12 are disposed at the first hub 30, and the first
and second ends of the second wire 14 are disposed at the second
hub (such as the second hub 119 of FIG. 15). In another such
exemplary embodiment, the first ends of the first and second wires
12, 14 are disposed at the first hub 30, and the second ends of the
first and second wires 12, 14 are disposed at the second hub (such
as the hub 119 of FIGS. 12B, 13, and/or 15), among other possible
variations.
[0123] FIG. 23 is a flowchart of an exemplary embodiment of a
method 2300 for occluding an aperture defect in a heart. The method
2300 can be utilized in connection with the heart 1 of FIG. 1 and
the various embodiments of the occluder device 10 of FIGS. 2-22.
Specifically, the method 2300 preferably utilizes one or more
embodiments of the occluder devices 10 of FIGS. 2-22 to occlude an
aperture defect of a heart, such as the aperture defect 6A of the
heart 1 depicted in FIG. 1.
[0124] As depicted in FIG. 23, the method 2300 includes the step of
providing an occluder device (step 2302). In various embodiments,
the occluder device corresponds to the occluder device 10 depicted
in any of the embodiments depicted in FIGS. 2-22 and/or described
above. The occluder device preferably comprises a first flexible
wire (such as wire 12 described above) and a second flexible wire
(such as wire 14 described above). Each of the first and second
wires is comprised of a shape memory material. Each of the first
and second wires is shaped into first and second geometric forms
(such as forms 12A, 12B, 14A, and 14B described above) around an
inner region such that the first geometric form of the first wire
and the first geometric form of the second wire form a first plate
(such as plate 16 described above) in a first plane, and the second
geometric form 12B of the first wire 12 and the second geometric
form 14B of the second wire 14 form a second plate (such as plate
18 described above) in a second plane that is parallel to and
remote from the first plane. The first and second plates are
separated by a waist (such as waist 20 described above) formed from
two portions of the first wire and two portions of the second wire.
A sealed covering (such as covering 24A or 24B described above) is
preferably disposed over at least one of the first and second
plates. The covering provides a seal for the aperture defect (such
as the defect 6A of the heart 1 described above). Each of the first
and second wires has a first end and a second end. Each of the
first and second ends of the first and second wires are connected
to a hub (such as hub 30 described above). The hub further
comprises a delivery attachment mechanism (for example, that
includes or is used in connection with the catheter 40 described
above) for attachment to a removable deployment cable (such as
deployment cable 34 described above).
[0125] The method 2300 also includes the step of attaching the
occluder device to the removable deployment cable (step 2304). The
occluder device is placed within a flexible delivery catheter (such
as the catheter 40 described above) having an open channel (such as
the channel 42 described above) (step 2306). The catheter is fed
into a blood vessel system (such as a blood vessel system of the
heart 1 described above) and advanced via the blood vessel system
to the aperture defect in the heart (step 2308). The catheter, with
the occluder device disposed within, is similarly advanced through
the aperture defect (step 2310).
[0126] In certain optional embodiments, a balloon sub-process 2312
is also utilized in occluding the aperture defect in the heart. In
one such embodiment, depicted in FIG. 23, a balloon is advanced
into the heart through the open channel toward the occluder device
at the aperture defect (step 2314). The balloon is also inserted
into the waist of the occluder device (step 2316). The balloon is
then inflated (step 2318), in order to help position the occluder
device proximate the heart defect. Once the occluder device is
properly positioned, the balloon is deflated (step 2320) and then
removed from the waist of the occluder device (step 2322).
[0127] In other optional embodiments, a hook sub-process 2324 may
be utilized in occluding the aperture defect in the heart. In one
such embodiment, depicted in FIG. 23, a hook (such as one or more
of the hooks 136, 232 described above), is engaged with the
delivery attachment mechanism (such as the catheter) (step 2326),
preferably via a screw system. The hook is manipulated using the
delivery attachment mechanism and used to reposition the occluder
device (step 2328). In certain embodiments, the hook may also be
utilized to retrieve the occluder device by exerting force on the
delivery attachment mechanism in a direction away from the heart
(step 2330).
[0128] The catheter next is withdrawn from the occluder device
(step 2332). Preferably, the catheter is withdrawn from the
occluder device in step 2332 in a manner such that the first plate
of the occluder device expands on a first side of the aperture
defect. In addition, the catheter is further withdrawn from the
occluder device such that the second plate of the occluder device
expands on a second side of the aperture defect (step 2334).
Preferably, the catheter is withdrawn from the occluder device in
step 2334 in a manner, such that the waist of the occluder device
expands by memory retention within the aperture defect to
self-center the occluder device. The catheter is then withdrawn
from the blood vessel system (step 2336), and the deployment cable
is removed from the hub of the occluder device (step 2338).
[0129] It will be appreciated that certain steps of the method 2300
may vary in certain embodiments. It will also be appreciated that
certain steps of the method 2300 may occur in a different order
than is depicted in FIG. 23. For example, the optional hook
sub-process 2324 may be used before the optional balloon
sub-process 2312. It will similarly be appreciated that certain
steps of the method 230 may occur simultaneously with one
another.
[0130] FIG. 24A is a schematic representation of a human heart 400
with a perimembranous VSD 6D. The heart 400 includes a right atrium
2, a left atrium 3, a right ventricle 4, and a left ventricle 5.
The right ventricle 4 is separated from the left ventricle 5 by a
ventricular septum 7. The ventricular septum 7 includes a
perimembranous VSD 6D. The margins of the perimembranous VSD 6D are
located partly in the membranous area of the ventricular septum 7
and partly in the muscular area of the ventricular septum 7. As
depicted in FIG. 1, a perimembranous VSD 6D is located in an area
of the ventricular septum 7 that is superior to a muscular VSD
6C.
[0131] A perimembranous VSD 6D can be more challenging to treat
using an occlusion device than other types of VSDs, e.g., the
muscular VSD 6C. One issue that makes perimembranous VSDs 6D more
challenging to treat is their close proximity to other anatomical
areas of the heart, such as the aortic valve 402, mitral valve 403,
and tricuspid valve 405. In some instances, perimembranous VSDs 6D
may be located juxta-aortic valve, juxta-mitral valve, and/or
juxta-tricuspid valve. When treating perimembranous VSDs 6D using
an occlusion device, any or all such valves can be potentially
injured or impeded. For example, perimembranous VSDs 6D are often
located in the left ventricle outflow tract just beneath the aortic
valve 402. The short portion of the ventricular septum located
superior to the perimembranous VSD 6D and inferior to the aortic
valve 402 is the subaortic rim 404. Because of the close proximity
to the aortic valve 402, the subaortic rim 404 area is generally
too small to allow for a full occluder disc to be used in the left
ventricle 5. That is, if a portion of an occluder disc is
positioned on or applies pressure to the subaortic rim 404, the
pressure or physical interference from the disc may impede the
proper functioning of the aortic valve 402. Such pressure or
physical interferences can result in adverse effects including, for
example, aortic regurgitation.
[0132] Perimembranous VSDs 6D are also challenging to treat with an
occlusion device because of their close proximity to the electrical
conduction system of the heart known as the atrioventricular (AV)
bundle. The AV bundle controls the contraction or beating of the
chambers of the heart. The AV bundle includes specialized muscle
fibers that regulate the heartbeat by conducting impulses from the
AV node in the right atrium 2 to the right and left ventricles 4
and 5. A portion of the AV bundle tends to be located at the
superior margin of a perimembranous VSD 6D, that is, in the
subaortic rim 404 area. If pressure is applied to the subaortic rim
404 containing the AV bundle, the AV electrical signal can be
slowed or disrupted, and cardiac arrhythmia can result. If an
occluder device for treating a perimembranous VSD 6D contacts the
subaortic rim 404, the pressure exerted on the AV bundle can result
in adverse effects such as cardiac arrhythmia.
[0133] Accordingly, to avoid such adverse effects, in some
embodiments it may not be practical or desirable to use a full 360
degree circular disc (a "full disc") on the left side of an
occlusion device, i.e., in the left ventricle 5. Rather, in some
embodiments, a portion of a full disc (a "partial disc") can be
advantageously used on the left side. For example, in some
embodiments, a partial disc having an arc of 180-240 degrees may be
desirable. In some embodiments, a partial disc comprising a
semi-circle of approximately 180 degrees is used on the left side.
In some embodiments, a partial disc comprising a circular sector
with an arc of less than 180 degrees is used. The partial disc can
be oriented in relation to the heart 400 to substantially avoid
contact with or applying pressure onto the subaortic rim 404. In
some embodiments, the partial disc comprises two or more portions,
or sub-discs, as described further below in reference to FIG.
26-28.
[0134] FIG. 24B is a schematic representation of a human heart 400,
and a schematic representation of an asymmetrical occlusion device
440 installed in the perimembranous VSD 6D of the heart 400. In
some embodiments, the asymmetrical occlusion device 440 is
well-suited for treating a perimembranous VSD 6D because the
asymmetrical occlusion device 440 does not make substantial contact
with the subaortic rim 404. In some embodiments, the asymmetrical
occlusion device 440 (shown in a side view) includes a full disc on
the right side, i.e. in the right ventricle 4. On the left side,
i.e., in the left ventricle 5, the asymmetrical occlusion device
440 includes a partial disc. In some embodiments, the partial disc
contacts portions of the ventricular septum 7 that are located
inferior to the subaortic rim 404 while avoiding substantial
contact with the subaortic rim 404 or with the aortic valve 402,
mitral valve 403, and tricuspid valve 405. An asymmetrical
occlusion device 440 having such a partial disc configuration on
the left side can occlude a perimembranous VSD 6D while avoiding
adverse interference with one or more of the aortic valve 402,
mitral valve 403, tricuspid valve 405, and/or the AV bundle of the
heart 400.
[0135] FIG. 25 is a side view of a schematic illustration of the
example asymmetrical occlusion device 440. In general, the
asymmetrical occlusion device 440 includes three regions: (i) an
occluder region 450, (ii) an attachment region 460, and (iii) a
securing region 470. The attachment region 460 can interconnect the
occluder region 450 to the securing region 470.
[0136] In some embodiments, the occluder region 450 includes a full
disc 454 (shown in side view). When the asymmetrical occlusion
device 440 is implanted in a heart to treat a perimembranous VSD,
the full disc 454 can be located in the right ventricle abutting
the ventricular septum (also refer to FIG. 24B). The full disc 454
may also be referred to as the proximal disc, because the full disc
454 can be proximal to a delivery catheter whereas the rest of the
asymmetrical device 440 can be distal to the delivery catheter. The
full disc 454 has a diameter 458 and a radius 478. In some
embodiments, the diameter 458 is in the range of about 20-26 mm,
about 16-30 mm, or about 10-36 mm. The diameter 458 is typically
selected in general accordance with the size of the heart and the
size of the VSD being treated. The full disc 454 defines at least
one disc plane 452. Because FIG. 25 shows a side view of the
asymmetrical occlusion device 440, the disc plane 452 is along the
line shown for disc plane 452 and 90 degrees to the surface of the
figure.
[0137] In some embodiments, the attachment region 460 of the
asymmetrical occlusion device 440 includes a waist 466. When the
asymmetrical occlusion device 440 is implanted in a heart, the
waist 466 can pass through the aperture of the perimembranous VSD.
In some embodiments, the waist 466 defines a transverse
cross-sectional shape that can be represented by a circle with a
diameter 468. In some embodiments, the waist diameter 468 is in the
range of about 12-18 mm, about 8-22 mm, or about 4-26 mm. The waist
diameter 468 can be selected in correlation with the size of the
aperture of the perimembranous VSD being treated. In some patients,
the aperture of the perimembranous VSD will be substantially
non-circular, such as elliptical. In cases when the aperture is
elliptical, in some embodiments the waist diameter 468 is selected
in correlation to the minor axis of the elliptical aperture. In
some embodiments, the waist 466 has an axial length 467. The axial
length 467 can be selected in correlation to the axial length of
the tunnel of the perimembranous VSD being treated. In some
embodiments, the axial length 467 of the occluder device is
adjustable by the clinician in situ during the implantation
procedure. The attachment region 460 can define a longitudinal axis
462.
[0138] In some embodiments, the securing region 470 includes a
partial disc 474. When the asymmetrical occlusion device 440 is
implanted in a heart to treat a perimembranous VSD, the partial
disc 474 can be located on the ventricular septum in the left
ventricle such that the partial disc 474 is generally inferior to
the aperture of the perimembranous VSD. The partial disc 474 may
also be referred to as the distal disc because, during implantation
of the asymmetrical device 440, the partial disc 474 can be distal
in relation to the delivery catheter, whereas the rest of the
asymmetrical device 440 can be proximal to the delivery catheter.
As described further below in reference to FIG. 26, in some
embodiments the partial disc 474 includes multiple portions or
securing members (e.g., 480, 482, and 484 of FIG. 26) each having a
major axis. In some embodiments, the major axes of the securing
members generally define a partial disc plane 472. In some
embodiments, the major axes of the securing members may not all
reside on a common plane (see e.g., FIG. 28). The partial disc 474
can have a length 476 that generally defines, for example, the
length of the securing members as measured from axis 462 to the
free-ends of the securing members. In some embodiments, the length
476 is approximately equal to the radius 478 of the full disc 454.
However, in some embodiments, the length 476 of the partial disc
474 is less than or greater than the radius 478 of the full disc
454. In some embodiments, the partial disc 474 has multiple
securing members with disparate lengths (see e.g., FIG. 27A).
[0139] The relative orientations of the occluder region 450,
attachment region 460, and securing region 470 with respect to each
other will now be described. While the asymmetrical occlusion
device 440 shown in FIG. 25 is used to explain the configuration of
the regions with respect to each other, the example asymmetrical
occlusion device 440 is merely one example embodiment of the
occlusion devices provided herein. Other embodiments having
regional configurations that are different than asymmetrical
occlusion device 440 are also envisioned within the scope of this
disclosure.
[0140] The angular relationship between the disc plane 452 and the
axis 462 of the attachment region 460 is represented by angle 456.
In the example asymmetrical occlusion device 440 embodiment shown,
the axis 462 of the attachment region 460 is generally
perpendicular to disc plane 452. That is, in this example, angle
456 is approximately 90 degrees. In some embodiments, the angle 456
is more than or less than 90 degrees (see e.g., FIG. 28). In
general, the selection of an asymmetrical occlusion device 440 with
a particular angle 456 can be made in accordance with the anatomy
of the patient. That is, in some patients the aperture of the
perimembranous VSD will be generally orthogonal to the nearby
surface of the ventricular septum in the right ventricle. In that
case, an asymmetrical occlusion device 440 with an angle 456 of
about 90 degrees would be appropriate to treat the VSD. In some
patients, the aperture of the perimembranous VSD may be at a
non-orthogonal angle in relation to the nearby surface of the
ventricular septum in the right ventricle. In such cases, an
asymmetrical occlusion device 440 with an angle 456 that
approximately matches the non-orthogonal angle of the aperture in
relation to the nearby surface of the ventricular septum can be
selected. In some embodiments, the angle 456 of the occluder device
is adjustable by the clinician either before the implantation
procedure or in situ during the implantation procedure.
[0141] The angular relationship between the disc plane 452 and the
partial disc plane 472 is represented by angle 464. In the example
asymmetrical occlusion device 440, the angle 464 is approximately
20 degrees. However, in some embodiments, the angle 464 is zero
degrees. That is, in some embodiments the disc plane 452 and the
partial disc plane 472 are substantially parallel to each other. In
some embodiments, the angle 464 is within a range of about 0-60
degrees, about 10-50 degrees, or about 20-40 degrees. The angle 464
can be selected in accordance with the anatomy of the patient. Some
patients may have the left and right surfaces of the ventricular
septum near the perimembranous VSD substantially parallel to each
other. In that case, an asymmetrical occlusion device 440 with an
angle 464 of zero degrees may be selected. However, in some
patients the left and right surfaces of the ventricular septum near
the perimembranous VSD may be at a non-zero angle in relation to
each other. In such cases, an asymmetrical occlusion device 440
with an angle 464 that is approximately equal to the angle between
the left and right surfaces of the ventricular septum near the
perimembranous VSD may be selected. In some embodiments, the angle
464 of the occluder device is adjustable by the clinician either
before the implantation procedure or in situ during the
implantation procedure.
[0142] It should be recognized that in some embodiments the force
exerted on the ventricular septum by the full disc 454 and the
partial disc 474 should be only a light pressure. A light amount of
pressure can help the asymmetrical occlusion device 440 maintain
proper position in relation to the anatomy of the patient's heart.
However, too much pressure from the asymmetrical occlusion device
440 may induce adverse effects, such as adverse effects to the
heart valves and AV bundle as described above.
[0143] FIG. 26 is a perspective view of an example asymmetrical
occlusion device 440. In general, the asymmetrical occlusion device
440 includes a full disc 454, a waist 466, a partial disc 474, and
a delivery attachment hub 30. The asymmetrical occlusion device 440
embodiment comprises two separate uniquely shaped memory wires 486
and 488. The wires 486 and 488 can be substantially similar to the
wires 12 and 14 described above. While the example asymmetrical
occlusion device 440 includes two wires 486 and 488, some
embodiments use one wire, three wires, or four wires or more to
form an asymmetrical occlusion device.
[0144] In some embodiments, the asymmetrical occlusion device 440
is self-centering. In some embodiments, the waist 466 is made of
four wire portions as shown. In some embodiments, the waist 466 is
made of more or fewer than four wire portions. In some embodiments,
the wire portions of waist 466 substantially conform to the size
and shape of the aperture of a perimembranous VSD. In some
embodiments, the wire portions of waist 466 exert enough radial
force to provide a self-centering feature, while not pressing
against the aperture edges in a manner that exacerbates the defect
or affects the functioning of the heart valves or AV bundle.
[0145] In some embodiments, the wire portions of the waist 466 are
more rigid than the wire portions of the full disc 454 and the
partial disc 474. In other words, in some embodiments, physical
conformance by the asymmetrical occlusion device 440 to the
landscape of the ventricular septum is primarily as a result of
deflection by the full disc 454 and/or partial disc 474 rather than
by deflection of the wire portions of the waist 466. In some such
embodiments, the waist 466 should not inhibit the abilities of the
full disc 454 and the partial disc 474 to conform to the topography
of the underlying tissue that the discs 454 and 474 make contact
with. In some embodiments, the asymmetrical occlusion device 440 is
fully repositionable and retrievable after deployment.
[0146] In some embodiments, the full disc 454 and the partial disc
474 have membranous coverings similar to those of other embodiments
described above (see e.g., FIGS. 6 and 7). In some embodiments,
neither the full disc 454 nor the partial disc 474 have membranous
coverings. In some embodiments, either the full disc 454 or the
partial disc 474 has a membranous covering, while the other does
not have a membranous covering. In some embodiments, the membranous
coverings can ensure more complete coverage and occlusion of the
aperture, and promote encapsulation and endothelialization of
tissue to encourage anatomical closure of the aperture. The
membranous coverings can be substantially as described above in
reference to coverings 24A and 24B. In some embodiments, the
encapsulation and endothelialization of tissue promoted by the
membranous coverings avoid a need for supplementary anchoring
devices, such as barbs and hooks. In some embodiments,
supplementary anchoring devices are included irrespective of the
presence of membranous coverings.
[0147] The partial disc 474 of example asymmetrical occlusion
device 440 includes three securing members 480, 482, and 484. In
some embodiments, each securing member 480, 482, and 484 is
individually flexible. As such, the securing members 480, 482, and
484 are individually conformable to the topography of the
ventricular septum tissue with which the securing members 480, 482,
and 484 make contact. This configuration can help prevent or
minimize device trauma to the ventricular septum, while
substantially securing the asymmetrical occlusion device 440 in the
desired location on the ventricular septum. Adverse effects, such
as aortic regurgitation and cardiac block, can thereby be minimized
or avoided altogether--despite the close proximity of the
perimembranous VSD to the heart valves and AV bundle.
[0148] In some embodiments, the three securing members 480, 482,
and 484 each include one or more visualization markers, such as
radiopaque markers 490, 492, and 494. The markers can assist a
clinician with radiographic visualization of the asymmetrical
occlusion device 440 so that the clinician can orient the device as
desired in relation to the anatomy of the patient. Radiopaque
markers can also be included on other locations on the asymmetrical
occlusion devices. In some embodiments, materials are added to the
frame elements to enhance visualization of the frame elements.
[0149] The transcatheter implantation procedure of an asymmetrical
occlusion device can be performed substantially as described in
reference to FIGS. 8-10 above. In some embodiments, restriction
wires are included to restrict the circumference of the waist 466,
as desired.
[0150] FIGS. 27A and 27B are schematic representations of two
embodiments of asymmetrical occlusion devices 500 and 550. These
example embodiments illustrate some of the different design
configurations that are possible by adjusting various features of
the asymmetrical occlusion devices provided herein. For example, by
altering certain features of the partial disc as described below,
multiple design configurations and combinations are possible.
[0151] FIG. 27A illustrates an asymmetrical occlusion device 500
having a full disc 454 and a partial disc 510. The partial disc 510
includes three securing members 512, 514, and 516. In this
embodiment, the side securing members 514 and 516 are mirror images
of each other. In some embodiments, each securing member has its
own unique design. In some embodiments, the partial disc 510 can be
asymmetrical such that none of the securing members mirror each
other.
[0152] The lengths and widths of the various securing members 512,
514, and 516 can be determined to provide the particular desired
features of the partial disc 510. For example, in the embodiment of
partial disc 510, the length 518 of the securing members 514 and
516 is less than the length 520 of the securing member 512. In some
embodiments, the lengths of the securing members are greater than
the radius of the full disc 454. In some embodiments, such as
asymmetrical occlusion device 500, the lengths of the securing
members are less than the radius of the full disc 454.
Additionally, the widths of the securing members can be
individually distinct, or the widths can be equivalent to the
widths of other securing members. For example, the width 520 of
securing members 514 and 516 are equal to each other and less than
the width 522 of the securing member 512. In some embodiments, each
securing member has an individually unique length and/or width. In
some embodiments, two or more of the securing members, (but not
all) have their lengths or widths in common. In some embodiments,
all securing members have their lengths and widths in common.
[0153] Additional partial disc design characteristics that can
provide particular desired features can include, for example, the
number of securing members and the angular positioning of the
securing members. For example, as the asymmetrical occlusion device
500 shows, in some embodiments three securing members 512, 514, and
516 are used. In some embodiments, more or fewer than three
securing members are used. For example, in some embodiments, a
single securing member is used as the partial disc. In some
embodiments, four or more securing members are used as the partial
disc.
[0154] The angular positions of the securing members can also be
established as desired. For example, angle 524 of asymmetrical
occlusion device 500 represents the angular position of the
securing members 514 and 516 in relation to a plane containing the
axis 504. In some embodiments, the angle 524 is approximately zero.
In some embodiments, the angle 524 is anywhere between 0-90
degrees. For example, the angular position of securing member 512
in relation to a plane containing the axis 504 is approximately 90
degrees. As depicted by asymmetrical occlusion device 550, in some
embodiments the angle 526 is approximately 45 degrees. As discussed
above in reference to FIG. 25, the relative angles of the planes
452, 472 defined by the full disc 454 and the partial disc 474 are
another design characteristic that can be selected in some
embodiments.
[0155] In some embodiments, an open space 534 is located between
adjacent securing members. In some embodiments, the securing
members abut one another such that there is substantially no space
between the edges of adjacent securing members. In some
embodiments, the edges of adjacent securing members overlap each
other.
[0156] In some embodiments, individual securing members are
asymmetrical. That is, rather than having shapes that are mirror
images of each other on opposite sides of its longitudinal axis,
the shapes on opposite sides of the longitudinal axis can be
different from each other. For example, in some embodiments, one
side of a securing member has a substantially straight edge, while
the other side of the same securing member has a curved edge.
[0157] FIG. 27B schematically depicts an asymmetrical occlusion
device 550 including a full disc 454 and a partial disc 560. The
partial disc 560 includes two securing members 528 and 530. In this
embodiment, the two securing members 528 and 530 are mirror images
of each other. However, in some embodiments, each securing member
has its own unique design. In some embodiments, at least one
securing member has a design unique from one or more of the other
securing members. The securing members 528 and 530 are depicted as
having an angular position of angle 526 in relation to the plane
containing the axis 554. In this embodiment, the angle 526 is
approximately 45 degrees. In some embodiments, angles of 0-90
degrees are possible.
[0158] Securing members 528 and 530 are depicted as having
relatively wide widths 532 (as compared to securing members 514 and
516, for example). In some embodiments, such wide securing members
may advantageously distribute the clamping forces exerted by the
securing members over a larger area of the ventricular septum. By
distributing the clamping force over a larger area, the pressure
exerted on the ventricular septum can be lowered while maintaining
a sufficient clamping force to substantially secure the occlusion
device in the desired location.
[0159] FIG. 28 is a side view of a schematic representation of
another embodiment of an asymmetrical occlusion device 600. This
embodiment includes a full disc 610 with a disc plane 612, a waist
620 with an axis 622, and a partial disc 630 with securing members
632 and 634 having axes 636 and 638 respectively.
[0160] The asymmetrical occlusion device 600 illustrates additional
design variations in regard to how the regions of an asymmetrical
occlusion device can be configured in relation to each other. For
example, the axis 622 of the waist 620 is at an acute angle 614 in
relation to the disc plane 612. Such a feature can be useful, for
example, with perimembranous VSD apertures that are at a
non-orthogonal angle in relation to the nearby surface of the
ventricular septum in the right ventricle. In addition, the
asymmetrical occlusion device 600 illustrates that individual
securing members can each be oriented at different angles in
relation to the full disc plane 612. For example, the axis 636 of
securing member 632 is at an acute angle 640 in relation to the
disc plane 612, while the axis 638 of securing member 634 is
approximately parallel to the disc plane 612. The ability to have
securing members at various angles in relation to the full disc
plane 612 can enable an asymmetrical occlusion device to be shaped
in correlation to the particular anatomy of the patient, and result
in less potential for disruption to the heart valves and AV
bundle.
[0161] Some embodiments may comprise any combinations of the
embodiments described herein and/or described in the drawings. It
is understood that the disclosure is not confined to the particular
construction and arrangement of parts herein illustrated and
described, but embraces such modified forms thereof as come within
the scope of the following claims. Additionally, it will be
appreciated that various embodiments may be freely combined
together, and/or that various features of different embodiments may
be freely combined together.
[0162] While at least one exemplary embodiment has been presented
in the foregoing detailed description, it should be appreciated
that a vast number of variations exist. It should also be
appreciated that the exemplary embodiment or exemplary embodiments
are only examples, and are not intended to limit the scope,
applicability, or configuration of the invention in any way.
Rather, the foregoing detailed description will provide those
skilled in the art with a convenient road map for implementing an
exemplary embodiment of the invention, it being understood that
various changes may be made in the function and arrangement of
elements described in an exemplary embodiment without departing
from the scope of the invention as set forth in the appended claims
and their legal equivalents.
* * * * *