U.S. patent application number 12/722287 was filed with the patent office on 2010-07-01 for systems and methods for closing a hole in cardiac tissue.
This patent application is currently assigned to CVDevices, LLC (a California limited liability company). Invention is credited to Ghassan S. Kassab, Jose A. Navia, SR..
Application Number | 20100168791 12/722287 |
Document ID | / |
Family ID | 38957265 |
Filed Date | 2010-07-01 |
United States Patent
Application |
20100168791 |
Kind Code |
A1 |
Kassab; Ghassan S. ; et
al. |
July 1, 2010 |
SYSTEMS AND METHODS FOR CLOSING A HOLE IN CARDIAC TISSUE
Abstract
Systems and methods for closing a hold in cardiac tissue. In at
least one embodiment of a system for closing a hole in cardiac
tissue, the system comprises an engagement catheter having a first
and second lumen extending therethrough, an elongated wire capable
of insertion into the second lumen of the engagement catheter, a
plug capable of insertion into the second lumen of the engagement
catheter; an elongated shaft capable of insertion into the second
lumen of the engagement catheter, wherein the elongated wire is
sized for slidable insertion through the lumen of the shaft and the
hole of the plug.
Inventors: |
Kassab; Ghassan S.;
(Zionsville, IN) ; Navia, SR.; Jose A.; (Buenos
Aires, AR) |
Correspondence
Address: |
ICE MILLER LLP
ONE AMERICAN SQUARE, SUITE 3100
INDIANAPOLIS
IN
46282-0200
US
|
Assignee: |
CVDevices, LLC (a California
limited liability company)
Zionsville
IN
|
Family ID: |
38957265 |
Appl. No.: |
12/722287 |
Filed: |
March 11, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12596964 |
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PCT/US2008/053061 |
Feb 5, 2008 |
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12722287 |
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PCT/US2007/015207 |
Jun 29, 2007 |
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12596964 |
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60914452 |
Apr 27, 2007 |
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60914452 |
Apr 27, 2007 |
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60817421 |
Jun 30, 2006 |
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Current U.S.
Class: |
606/213 ;
600/37 |
Current CPC
Class: |
A61B 17/00234 20130101;
A61B 17/00491 20130101; A61B 2017/00575 20130101; A61B 2017/0065
20130101; A61M 2025/0039 20130101; A61B 2017/00606 20130101; A61M
25/0662 20130101; A61M 2025/0004 20130101; A61B 17/30 20130101;
A61M 25/04 20130101; A61M 2210/125 20130101; A61M 25/0084 20130101;
A61B 2017/306 20130101; A61B 17/0057 20130101; A61M 5/14 20130101;
A61N 1/0592 20130101; A61B 2017/00292 20130101; A61B 2017/00243
20130101 |
Class at
Publication: |
606/213 ;
600/37 |
International
Class: |
A61B 17/03 20060101
A61B017/03; A61B 17/00 20060101 A61B017/00 |
Claims
1. A system for closing a hole in cardiac tissue, the system
comprising: an engagement catheter comprising a proximal end, a
distal end, first and second lumens extending between the proximal
end and the distal end, and a vacuum port operatively connected to
the first lumen of the engagement catheter at the proximal end of
the engagement catheter, the vacuum port being capable of operative
connection to a vacuum source, wherein the first lumen of the
engagement catheter includes a suction port located at or near the
distal end of the engagement catheter, the suction port configured
to removably attach to a targeted tissue on the interior of a wall
of the heart, such that the suction port is capable of forming a
reversible seal with the targeted tissue when a vacuum source is
operatively attached to the vacuum port; an elongated wire capable
of insertion into the second lumen of the engagement catheter; a
plug having a first end, a second end, and a hole extending from
the first end to the second end, the plug being capable of
insertion into the second lumen of the engagement catheter; and an
elongated shaft having a proximal end, a distal end, and a lumen
extending from the proximal end to the distal end, the elongated
shaft being capable of insertion into the second lumen of the
engagement catheter; wherein the elongated wire is sized for
slidable insertion through the lumen of the shaft and the hole of
the plug.
2. The system of claim 1, wherein: the first end of the plug is
radiopaque.
3. The system of claim 2, wherein: the first end of the plug has a
smaller diameter than the second end of the plug.
4. The system of claim 3, wherein: the plug comprises an external
surface that has a screw-shaped ridge.
5. The system of claim 1, wherein: the elongated wire comprises an
elongated guide wire; and the hole in the plug is self-sealing,
6. A system for closing a hole in cardiac tissue, the system
comprising: an engagement catheter comprising a proximal end, a
distal end, first and second lumens extending between the proximal
end and the distal end, and a vacuum port operatively connected to
the first lumen of the engagement catheter at the proximal end of
the engagement catheter, the vacuum port being capable of operative
connection to a vacuum source, wherein the first lumen of the
engagement catheter includes a suction port located at or near the
distal end of the engagement catheter, the suction port configured
to removably attach to a targeted tissue on the interior of a wall
of the heart, such that the suction port is capable of forming a
reversible seal with the targeted tissue when a vacuum source is
operatively attached to the vacuum port; a delivery catheter
comprising a proximal end, a distal end, and a hollow tube
extending between the proximal end and the distal end, the delivery
catheter configured such that the hollow tube is capable of
insertion into the second lumen of the engagement catheter; an
elongated delivery wire having a proximal end and a distal end, the
distal end of the delivery wire being, capable of insertion through
the hollow tube of the delivery catheter; and a closure member
having a first face and a second face, the closure member being
capable of transitioning from a folded configuration within the
hollow tube of the delivery catheter to an expanded configuration
outside of the hollow tube of the delivery catheter; wherein the
first face of the closure member is configured for reversible
attachment to the distal end of the delivery wire.
7. The system of claim 6, wherein: the closure member comprises an
external cover and an internal cover; the first face of the closure
member comprises an outside face of the internal cover; and the
second face of the closure member comprises an outside face of the
external cover.
8. The system of claim 7, wherein: the internal cover further
comprises a first inside face; the external cover further comprises
a second inside face; and at least one of the first inside face and
the second inside face of the external cover comprises a
magnet.
9. The system of claim 7, wherein: the internal cover further
comprises a first inside face; the external cover further comprises
a second inside face; and an adhesive is attached to the first
inside face and the second inside face.
10. The system of claim 9, wherein: the closure member comprises a
biodegradable substance.
11. The system of claim 7, wherein: the external cover is attached
to the internal cover.
12. The system of claim 11, wherein: the closure member comprises
nitinol.
13. A method for closing a hole in a targeted tissue of a heart,
the method comprising the steps of: contacting a targeted tissue in
the interior of a heart with a distal end of an elongated tube, the
elongated tube having a first lumen and a second lumen; aspirating
the targeted tissue such that the targeted tissue is retracted away
from a pericardial sac surrounding the heart and a pericardial
space between the pericardial sac and the targeted tissue is
enlarged; inserting through the first lumen of the elongated tube a
delivery catheter having a lumen; inserting an elongated delivery
wire through the lumen of the delivery catheter, the elongated
delivery wire having an external cover that is capable of
transitioning from a folded configuration within the lumen of the
delivery catheter to an expanded configuration outside of the lumen
of the delivery catheter, the external cover being reversibly
attached to a distal end of the delivery wire; delivering the
external cover through the hole in the targeted tissue into the
pericardial space; placing the external cover onto the targeted
tissue from the pericardial space; releasing the external cover
from the delivery wire; and withdrawing the delivery wire from the
targeted tissue.
14. The method of claim 13, further comprising the steps of:
reversibly attaching an internal cover to the distal end of the
delivery wire, the internal cover being capable of transitioning
from a folded configuration within the lumen of the delivery
catheter to an expanded configuration outside of the lumen of the
delivery catheter; delivering the internal cover to the targeted
tissue in the interior of the heart; placing the internal cover
onto the targeted tissue from the interior of the heart; releasing
the internal cover from the delivery wire; and withdrawing the
delivery wire from the interior of the heart.
15. A method for closing a hole in a targeted tissue of a heart,
the method comprising the steps of: inserting a wire through a
lumen of an elongated tube and through a hole in a targeted tissue,
the elongated tube having a proximal end and a distal end adjacent
to the targeted tissue; inserting into the lumen of the elongated
tube and over the wire a plug having a first end, a second end, and
a hole extending from the first end to the second end; inserting
into the lumen of the elongated tube and over the wire an elongated
shaft having a proximal end, a distal end, and a hole extending
from the proximal end to the distal end; sliding the elongated
shaft toward the distal end of the elongated tube until the plug
approaches the hole in the targeted tissue; inserting the plug into
the hole in the targeted tissue; and withdrawing the elongated
shaft from the elongated tube,
16. The method of claim 15, wherein: the first end of the plug has
a diameter that is smaller than the diameter of the second end of
the plug.
17. The method of claim 16, wherein: at least a portion of the
first end of the plug is radiopaque,
18. The method of claim 17, further comprising the step of:
confirming the location of the plug using radiographic imaging.
19. The method of claim 15, wherein: the wire comprises a guide
wire; and the hole of the plug closes after the guide wire is
withdrawn from the hole of the plug.
20. A system for closing a hole in a targeted tissue, comprising: a
closure member having a head and a plurality of arms extending from
the head, the closure member capable of transitioning between an
open position and a closed position; and a delivery catheter
comprising a proximal end, a distal end, and a hollow tube
extending between the proximal end and the distal end, the delivery
catheter configured such that the closure member is capable of
insertion into the hollow tube when the closure member is in the
open position.
21. The system of claim 20, further comprising: an engagement
catheter comprising a proximal end, a distal end, a first lumen
extending between the proximal end and the distal end, and a vacuum
port operatively connected to the first lumen of the engagement
catheter at the proximal end of the engagement catheter, the vacuum
port being capable of operative connection to a vacuum source,
wherein the first lumen of the engagement catheter includes a
suction port located at or near the distal end of the engagement
catheter, the suction port configured to removably attach to a
targeted tissue on the interior of a wall of the heart, such that
the suction port is capable of forming a reversible seal with the
targeted tissue when a vacuum source is operatively attached to the
vacuum port; wherein the delivery catheter is configured for
inserted into the first lumen of the engagement catheter.
22. The system of claim 21, wherein: the plurality of arms of the
closure member comprise nitinol.
23. The system of claim 22, wherein: the plurality of arms of the
closure member comprise four arms,
24. A method for closing a hole in a targeted tissue of a heart,
the method comprising the steps of: providing a closure member
having a head and a plurality of arms extending from the head, the
closure member capable of transitioning between an open position
and a closed position; delivering the closure member to a heart
through a delivery catheter comprising a proximal end, a distal
end, and a hollow tube extending between the proximal end and the
distal end, the delivery catheter configured such that the closure
member is capable of insertion into the hollow tube when the
closure member is in the open position; deploying the closure
member such that the closure member contacts a targeted tissue of
the heart and transitions to the closed position.
25. The method of claim 24, wherein: the plurality of arms comprise
four arms.
26. The method of claim 25, wherein: the step of delivery the
closure member to the heart comprises advancing the closure member
through the delivery catheter by pushing on the head of the closure
member using a rod inserted into the hollow tube.
Description
PRIORITY
[0001] This U.S. continuation patent application is related to, and
claims the priority benefit of, U.S. Nonprovisional patent
application Ser. No. 12/596,964, filed Oct. 21, 2009, which is
related to, claims the priority benefit of, and is a U.S. national
stage application of, International Patent Application No.
PCT/US2008/053061, filed on Feb. 5, 2008, which (i) claims priority
to U.S. Provisional Patent Application Ser. No. 60/914,452, filed
Apr. 27, 2007, and (ii) is related to, claims the priority benefit
of and in at least some designated countries should be considered a
continuation-in-part application of, International Patent
Application No. PCT/US2007/015207, filed Jun. 29, 2007, which is
related to, and claims the priority benefit of, U.S. Provisional
Patent Application Ser. No. 60/914,452, filed Apr. 27, 2007, and
U.S. Provisional Patent Application Ser. No. 60/817,421, filed Jun.
30, 2006. The contents of each of these applications are hereby
incorporated by reference in their entirety into this
disclosure.
BACKGROUND
[0002] Ischemic heart disease, or coronary heart disease, kills
more Americans per year than any other single cause. In 2004, one
in every five deaths in the United States resulted from ischemic
heart disease. Indeed, the disease has had a profound impact
worldwide. If left untreated, ischemic heart disease can lead to
chronic heart failure, which can be defined as a significant
decrease in the heart's ability to pump blood. Chronic heart
failure is often treated with drug therapy.
[0003] Ischemic heart disease is generally characterized by a
diminished flow of blood to the myocardium and is also often
treated using drug therapy. Although many of the available drugs
may be administered systemically, local drug delivery ("LDD")
directly to the heart can result in higher local drug
concentrations with fewer systemic side effects, thereby leading to
improved therapeutic outcomes.
[0004] Cardiac drugs may be delivered locally via catheter passing
through the blood vessels to the inside of the heart. However,
endoluminal drug delivery has several shortcomings, such as: (1)
inconsistent delivery, (2) low efficiency of localization, and (3)
relatively rapid washout into the circulation.
[0005] To overcome such shortcomings, drugs may be delivered
directly into the pericardial space, which surrounds the external
surface of the heart. The pericardial space is a cavity formed
between the heart and the relatively stiff pericardial sac that
encases the heart. Although the pericardial space is usually quite
small because the pericardial sac and the heart are in such close
contact, a catheter may be used to inject a drug into the
pericardial space for local administration to the myocardial and
coronary tissues. Drug delivery methods that supply the agent to
the heart via the pericardial space offer several advantages over
endoluminal delivery, including: (1) enhanced consistency and (2)
prolonged exposure of the drug to the cardiac tissue.
[0006] In current practice, drugs are delivered into the
pericardial space either by the percutaneous transventricular
method or by the transthoracic approach. The percutaneous
transventricular method involves the controlled penetration of a
catheter through the ventricular myocardium to the pericardial
space. The transthoracic approach involves accessing the
pericardial space from outside the heart using a sheathed needle
with a suction tip to grasp the pericardium, pulling it away from
the myocardium to enlarge the pericardial space, and injecting the
drug into the space with the needle.
[0007] For some patients with chronic heart failure, cardiac
resynchronization therapy ("CRT") can be used in addition to drug
therapy to improve heart function. Such patients generally have an
abnormality in conduction that causes the right and left ventricles
to beat (i.e., begin systole) at slightly different times, which
further decreases the heart's already-limited function. CRT helps
to correct this problem of dyssynchrony by resynchronizing the
ventricles, thereby leading to improved heart function. The therapy
involves the use of an implantable device that helps control the
pacing of at least one of the ventricles through the placement of
electrical leads onto specified areas of the heart. Small
electrical signals are then delivered to the heart through the
leads, causing the right and left ventricles to beat
simultaneously.
[0008] Like the local delivery of drugs to the heart, the placement
of CRT leads on the heart can be challenging, particularly when the
target placement site is the left ventricle. Leads can be placed
using a transvenous approach through the coronary sinus, by
surgical placement at the epicardium, or by using an endocardial
approach. Problems with these methods of lead placement can include
placement at an improper location (including inadvertent placement
at or near scar tissue, which does not respond to the electrical
signals), dissection or perforation of the coronary sinus or
cardiac vein during placement, extended fluoroscopic exposure (and
the associated radiation risks) during placement, dislodgement of
the lead after placement, and long and unpredictable times required
for placement (ranging from about 30 minutes to several hours).
[0009] Clinically, the only approved non-surgical means for
accessing the pericardial space include the subxiphoid and the
ultrasound-guided apical and parasternal needle catheter
techniques, and each methods involves a transthoracic approach. In
the subxiphoid method, a sheathed needle with a suction tip is
advanced from a subxiphoid position into the mediastinum under
fluoroscopic guidance. The catheter is positioned onto the anterior
outer surface of the pericardial sac, and the suction tip is used
to grasp the pericardium and pull it away from the heart tissue,
thereby creating additional clearance between the pericardial sac
and the heart. The additional clearance tends to decrease the
likelihood that the myocardium will be inadvertently punctured when
the pericardial sac is pierced.
[0010] Although this technique works well in the normal heart,
there are major limitations in diseased or dilated hearts--the very
hearts for which drug delivery and CRT lead placement are most
needed. When the heart is enlarged, the pericardial space is
significantly smaller and the risk of puncturing the right
ventricle or other cardiac structures is increased. Additionally,
because the pericardium is a very stiff membrane, the suction on
the pericardium provides little deformation of the pericardium and,
therefore, very little clearance of the pericardium from the
heart.
[0011] Thus, there is need for an efficient, easy to use, and
relatively inexpensive technique that can be used to access the
heart for local delivery of therapeutic and diagnostic substances,
as well as of CRT leads and other types of leads.
BRIEF SUMMARY
[0012] Disclosed herein are devices, systems, and methods for
accessing the internal and external tissues of the heart. At least
some of the disclosed embodiments provide access to the external
surface of the heart through the pericardial space for localized
delivery of leads to the heart tissue. In addition, various
disclosed embodiments provide devices, systems, and methods for
closing a hole or wound in cardiac tissue.
[0013] For example, disclosed herein is a system for use with a
vacuum source for placing a lead into a tissue of a heart,
comprising an engagement catheter comprising a proximal end, a
distal end, and first and second lumens extending between the
proximal end and the distal end; a delivery catheter comprising an
elongated tube having a wall and a first lumen, wherein the
delivery catheter is configured such that the delivery catheter is
capable of at least partial insertion into the second lumen of the
engagement catheter; a lead having a tip at a distal end, the lead
configured for at least partial insertion into the first lumen of
the delivery catheter; and a vacuum port located at the proximal
end of the engagement catheter, the vacuum port being operatively
connected to the first lumen of the engagement catheter and capable
of operative connection to the vacuum source; wherein the first
lumen of the engagement catheter includes a suction port located at
or near the distal end of the engagement catheter, the suction port
being configured to removably attach to a targeted tissue on the
interior of a wall of the heart, such that the suction port is
capable of forming a reversible seal with the targeted tissue when
the vacuum source is operatively attached to the vacuum port, and
wherein the system is capable of enlarging a pericardial space
between the targeted tissue and a pericardial sac that surrounds
the heart by retracting the targeted tissue away from the
pericardial sac. In at least some embodiments, the first lumen of
the delivery catheter extends from approximately the proximal end
of the tube to or near the distal end of the tube, the first lumen
of the delivery catheter having a bend, relative to the tube, at or
near the distal end of the tube and an outlet through the wall of
the tube at or near the distal end of the tube. In addition, the
bend of the first lumen of the delivery catheter may form an angle
that is approximately 90-degrees.
[0014] Certain disclosed embodiments of the delivery catheter
disclosed herein may further comprise a second lumen extending from
approximately the proximal end of the tube to or near the distal
end of the tube, the second lumen of the delivery catheter having a
bend, relative to the tube, at or near the distal end of the tube
and an outlet through the wall of the tube at or near the distal
end of the tube. The bend of the second lumen of the delivery
catheter may form an angle that is approximately 90-degrees.
[0015] In certain embodiments, the lead comprises a pacing lead,
and the tip of the pacing lead has a substantially screw-like
shape.
[0016] The delivery catheter may further comprise a steering
channel extending from a proximal end of the tube to a distal end
of the tube and a steering wire system at least partially located
in the steering channel. The steering wire system may comprise a
first steering wire, a second steering wire, and a controller, each
of the first and second steering wires being attached to the wall
of the tube within the steering channel and the controller being
attached to a proximal end of each of the first and second steering
wires. The controller of the steering wire system may comprise a
first handle attached to the proximal end of the first steering
wire and a second handle attached to the proximal end of the second
steering wire.
[0017] In at least some embodiments, the controller of the steering
wire system comprises a torque system having a first rotatable
spool capable of collecting and dispensing the first steering wire
and a second rotatable spool capable of collecting and dispensing
the second steering wire.
[0018] In some embodiments, the steering wire system further
comprises a third steering wire; the first steering wire is
attached to the wall of the tube within the steering channel at the
distal end of the tube, the attachment between the first steering
wire and the wall forming a first attachment point; the second
steering wire is attached to the wall of the tube within the
steering channel at the distal end of the tube, the attachment
between the second steering wire and the wall forming a second
attachment point; the third steering wire is attached to the wall
of the tube within the steering channel at the distal end of the
tube, the attachment between the third steering wire and the wall
forming a third attachment point; and the third attachment point is
closer to the proximal end of the tube than is the first attachment
point or the second attachment point.
[0019] In some embodiments, the delivery catheter further comprises
a handle at or near the proximal end of the tube; and the
controller of the steering wire system is attached to the
handle.
[0020] Also disclosed herein is a delivery catheter for use in
accessing a pericardial space surrounding the external surface of a
heart, comprising an elongated tube comprising a wall extending
from a proximal end of the tube to a distal end of the tube, a
first lumen, and a steering channel extending from a proximal end
of the tube to a distal end of the tube, the steering channel
forming an orifice at the distal end of the tube; and a steering
wire system at least partially located in the steering channel, the
steering wire system comprising at least two steering wires
attached to the wall of the tube within the steering channel and a
controller attached to a proximal end of each of the at least two
steering wires; wherein the first lumen extends from approximately
the proximal end of the tube to or near the distal end of the tube,
the first lumen having a bend, relative to the tube, at or near the
distal end of the tube and an outlet through the wall of the tube
at or near the distal end of the tube. In at least some
embodiments, the steering channel of the tube and the orifice of
the tube are sized for insertion over an elongated guide wire such
that the elongated guide wire is inserted through the orifice and
into the steering channel. Certain embodiments further comprise a
pacing lead sized for delivery through the outlet of the first
lumen.
[0021] In certain embodiments, the at least two steering wires
comprise a first steering wire and a second steering wire; and the
controller of the steering wire system comprises a first handle
attached to the proximal end of the first steering wire and a
second handle attached to the proximal end of the second steering
wire. The controller of the steering wire system may comprise a
torque system having a first rotatable spool capable of collecting
and dispensing the first steering wire and a second rotatable spool
capable of collecting and dispensing the second steering wire. The
first rotatable spool may be attached to a first rotatable dial
such that rotation of the first rotatable dial causes rotation of
the first rotatable spool; and the second rotatable spool may be
attached to a second rotatable dial such that rotation of the
second rotatable dial causes rotation of the second rotatable
spool. In some embodiments, each of the at least two steering wires
is attached to the wall of the tube within the steering channel at
the distal end of the tube.
[0022] In certain embodiments, the at least two steering wires
comprise a first steering wire, a second steering wire, and a third
steering wire; and the first steering wire is attached to the wall
of the tube within the steering channel at the distal end of the
tube, the attachment between the first steering wire and the wall
forming a first attachment point; the second steering wire is
attached to the wall of the tube within the steering channel at the
distal end of the tube, the attachment between the second steering
wire and the wall forming a second attachment point; the third
steering wire is attached to the wall of the tube within the
steering channel at the distal end of the tube, the attachment
between the third steering wire and the wall forming a third
attachment point; and the third attachment point is closer to the
proximal end of the tube than is the first attachment point or the
second attachment point.
[0023] Some embodiments further comprise a sensing lead positioned
at least partially within the first lumen, and some embodiments
further comprise a micro-camera system positioned at least
partially within the second lumen. Further, a laser Doppler tip may
be positioned at least partially within the second lumen.
[0024] At least some embodiments disclosed herein include a method
of placing a lead in a tissue of a heart, the method comprising:
extending into a blood vessel an elongated tube having a proximal
end, a distal end, and a first lumen, such that the distal end of
the tube is in contact with a targeted tissue on the interior of a
wall of the heart; aspirating the targeted tissue such that the
wall of the heart is retracted away from a pericardial sac
surrounding the heart to enlarge a pericardial space between the
pericardial sac and the wall of the heart; accessing the
pericardial space through the targeted tissue; inserting at least
the distal end of an elongated guide wire into the pericardial
space; inserting into the first lumen of the elongated tube and
over the elongated guide wire a delivery catheter comprising a
first lumen, wherein the first lumen of the delivery catheter has a
bend at or near the distal end of the delivery catheter and an
outlet at or near the distal end of the delivery catheter;
advancing at least the distal end of the delivery catheter through
the targeted tissue into the pericardial space; directing the
delivery catheter such that the outlet of the first lumen of the
delivery catheter is adjacent to the tissue of the heart; extending
a lead through the first lumen of the delivery catheter into the
tissue of the heart; withdrawing the delivery catheter from the
pericardial space; and withdrawing the guide wire from the
pericardial space. In some embodiments, the delivery catheter
further comprises a steering channel and a steering wire system
located at least partially within the steering channel; and the
step of directing the delivery catheter such that the outlet of the
first lumen of the delivery catheter is adjacent to the tissue of
the heart comprises directing the delivery catheter with the
steering wire system. Certain embodiments may further comprise the
step of extending a laser Doppler tip through a second lumen of the
delivery catheter to the pericardial space.
[0025] In some embodiments, the lead is a pacing lead; and the
steering wire system further comprises at least two steering wires
attached to the delivery catheter inside the steering channel and a
controller attached to the proximal ends of the at least two
steering wires, the controller being capable of collecting and
dispensing at least one of the at least two steering wires.
[0026] In certain embodiments, the step of directing the delivery
catheter using the steering wire system comprises using the
controller to tighten at least one of the at least two steering
wires.
[0027] Certain embodiments may further comprise inserting into the
targeted tissue over the guide wire a plug having a first end, a
second end, and a hole extending from the first end to the second
end. In some embodiments, the hole of the plug is self-sealing
after removal of the guide wire.
[0028] Other embodiments disclosed herein include a system for
closing a hole in cardiac tissue, the system comprising an
engagement catheter comprising a proximal end, a distal end, first
and second lumens extending between the proximal end and the distal
end, and a vacuum port operatively connected to the first lumen of
the engagement catheter at the proximal end of the engagement
catheter, the vacuum port being capable of operative connection to
a vacuum source, wherein the first lumen of the engagement catheter
includes a suction port located at or near the distal end of the
engagement catheter, the suction port configured to removably
attach to a targeted tissue on the interior of a wall of the heart,
such that the suction port is capable of forming a reversible seal
with the targeted tissue when a vacuum source is operatively
attached to the vacuum port; an elongated wire capable of insertion
into the second lumen of the engagement catheter; a plug having a
first end, a second end, and a hole extending from the first end to
the second end, the plug being capable of insertion into the second
lumen of the engagement catheter; and an elongated shaft having a
proximal end, a distal end, and a lumen extending from the proximal
end to the distal end, the elongated shaft being capable of
insertion into the second lumen of the engagement catheter; wherein
the elongated wire is sized for slidable insertion through the
lumen of the shaft and the hole of the plug. The first end of the
plug may be radiopaque. In some embodiments, the first end of the
plug has a smaller diameter than the second end of the plug.
Certain embodiments may include a plug having an external surface
that has a screw-shaped ridge.
[0029] In some embodiments, the elongated wire comprises a lead,
while in other embodiments the elongated wire comprises an
elongated guide wire.
[0030] At least some disclosed embodiments include a system for
closing a hole in cardiac tissue, the system comprising: an
engagement catheter comprising a proximal end, a distal end, first
and second lumens extending between the proximal end and the distal
end, and a vacuum port operatively connected to the first lumen of
the engagement catheter at the proximal end of the engagement
catheter, the vacuum port being capable of operative connection to
a vacuum source, wherein the first lumen of the engagement catheter
includes a suction port located at or near the distal end of the
engagement catheter, the suction port configured to removably
attach to a targeted tissue on the interior of a wall of the heart,
such that the suction port is capable of forming a reversible seal
with the targeted tissue when a vacuum source is operatively
attached to the vacuum port; a delivery catheter comprising a
proximal end, a distal end, and a hollow tube extending between the
proximal end and the distal end, the delivery catheter configured
such that the hollow tube is capable of insertion into the second
lumen of the engagement catheter; an elongated delivery wire having
a proximal end and a distal end, the distal end of the delivery
wire being capable of insertion through the hollow tube of the
delivery catheter; and a closure member having a first face and a
second face, the closure member being capable of transitioning from
a folded configuration within the hollow tube of the delivery
catheter to an expanded configuration outside of the hollow tube of
the delivery catheter; wherein the first face of the closure member
is configured for reversible attachment to the distal end of the
delivery wire. In at least some embodiments, the closure member
comprises an external cover and an internal cover; the first face
of the closure member comprises an outside face of the internal
cover; and the second face of the closure member comprises an
outside face of the external cover. Further, the internal cover may
further comprise an inside face; the external cover may further
comprise an inside face; and at least one of the inside face of the
internal cover and the inside face of the external cover may
comprise a magnet.
[0031] In at least some embodiments, the external cover is attached
to the internal cover. In some embodiments, the internal cover
further comprises an inside face; the external cover further
comprises an inside face; and an adhesive is attached to the inside
face of the internal cover and the inside face of the external
cover.
[0032] The closure member may comprise a biodegradable substance.
In some embodiments, the closure member comprises nitinol.
[0033] Also disclosed herein are embodiments including a method for
closing a hole in a targeted tissue of a heart, the method
comprising: contacting the targeted tissue in the interior of the
heart with a distal end of an elongated tube, the elongated tube
having a first lumen and a second lumen; aspirating the targeted
tissue such that the targeted tissue is retracted away from a
pericardial sac surrounding the heart and a pericardial space
between the pericardial sac and the targeted tissue is enlarged;
inserting through the first lumen of the elongated tube a delivery
catheter having a lumen; inserting an elongated delivery wire
through the lumen of the delivery catheter, the elongated delivery
wire having an external cover that is capable of transitioning from
a folded configuration within the lumen of the delivery catheter to
an expanded configuration outside of the lumen of the delivery
catheter, the external cover being reversibly attached to a distal
end of the delivery wire; delivering the external cover through the
hole in the targeted tissue into the pericardial space; placing the
external cover onto the targeted tissue from the pericardial space;
releasing the external cover from the delivery wire; and
withdrawing the delivery wire from the targeted tissue. In some
embodiments, the method further comprises the steps of: reversibly
attaching an internal cover to the distal end of the delivery wire,
the internal cover being capable of transitioning from a folded
configuration within the lumen of the delivery catheter to an
expanded configuration outside of the lumen of the delivery
catheter; delivering the internal cover to the targeted tissue in
the interior of the heart; placing the internal cover onto the
targeted tissue from the interior of the heart; releasing the
internal cover from the delivery wire; and withdrawing the delivery
wire from the interior of the heart.
[0034] At least some embodiments include a method for closing a
hole in a targeted tissue of a heart, the method comprising:
providing access to the hole in the targeted tissue by inserting a
wire through a lumen of an elongated tube and through the hole in
the targeted tissue, the elongated tube having a proximal end and a
distal end adjacent to the targeted tissue; inserting into the
lumen of the elongated tube and over the wire a plug having a first
end, a second end, and a hole extending from the first end to the
second end; inserting into the lumen of the elongated tube and over
the wire an elongated shaft having a proximal end, a distal end,
and a hole extending from the proximal end to the distal end;
sliding the elongated shaft toward the distal end of the elongated
tube until the plug approaches the hole in the targeted tissue;
inserting the plug into the hole in the targeted tissue; and
withdrawing the elongated shaft from the elongated tube. In some
embodiments, the first end of the plug has a diameter that is
smaller than the diameter of the second end of the plug, and the
first end of the plug may be radiopaque. The embodiment may further
comprise the step of confirming the location of the plug using
radiographic imaging.
[0035] In at least some embodiments, the wire comprises a guide
wire, and the hole of the plug closes after the guide wire is
withdrawn from the hole of the plug.
[0036] Certain embodiments include a delivery catheter for use in
accessing a pericardial space surrounding the external surface of a
heart, comprising: an elongated tube comprising a wall extending
from a proximal end of the tube to a distal end of the tube, a
first lumen, and a second lumen; wherein the first lumen extends
from approximately the proximal end of the tube to or near the
distal end of the tube, the first lumen having a bend, relative to
the tube, at or near the distal end of the tube and an outlet
through the wall of the tube at or near the distal end of the tube;
and wherein the second lumen extends from approximately the
proximal end of the tube to or near the distal end of the tube, the
second lumen having a bend, relative to the tube, at or near the
distal end of the tube and an outlet through the wall of the tube
at or near the distal end of the tube. The bend of the first lumen
may form an angle that is approximately 90-degrees, and the bend of
the second lumen may form an angle that is approximately
90-degrees.
[0037] At least some embodiments further comprise a laser Doppler
tip positioned at least partially within the second lumen. A needle
may be positioned at least partially within the first lumen.
[0038] Disclosed herein are embodiments including a method of
injecting a substance into a cardiac tissue from the pericardial
space surrounding the external surface of a heart, the method
comprising: extending into a blood vessel an elongated tube having
a proximal end, a distal end, and a first lumen, such that the
distal end of the tube is in contact with a targeted tissue on the
interior of a wall of the heart; aspirating the targeted tissue
such that the wall of the heart is retracted away from a
pericardial sac surrounding the heart to enlarge a pericardial
space between the pericardial sac and the wall of the heart;
accessing the pericardial space through the targeted tissue;
inserting at least the distal end of an elongated guide wire into
the pericardial space; inserting into the first lumen of the
elongated tube and over the elongated guide wire a delivery
catheter comprising a first lumen, wherein the first lumen of the
delivery catheter has a bend at or near the distal end of the
delivery catheter and an outlet at or near the distal end of the
delivery catheter; advancing at least the distal end of the
delivery catheter through the targeted tissue into the pericardial
space; directing the delivery catheter such that the outlet of the
first lumen of the delivery catheter is adjacent to the external
surface of the heart; extending a needle through the first lumen of
the delivery catheter into the cardiac tissue; injecting the
substance into the cardiac tissue; and withdrawing the delivery
catheter from the pericardial space. The substance may comprise
gene cells, growth factors, and/or a biodegradable synthetic
polymer. The biodegradable synthetic polymer may be selected from
the group consisting of polylactides, polyglycolides,
polycaprolactones, polyanhydrides, polyamides, and polyurethanes.
In certain embodiments, the substance comprises a tissue inhibitor,
such as a metalloproteinase. In at least certain embodiments, the
substance comprises RGD-liposome biologic glue.
[0039] In at least some embodiments, the delivery catheter further
comprises a second lumen, wherein the second lumen of the delivery
catheter has a bend at or near the distal end of the delivery
catheter and an outlet at or near the distal end of the delivery
catheter. The delivery catheter may further comprise a laser
Doppler tip. In some embodiments, the method further comprises the
step of measuring the thickness of the cardiac tissue using the
laser Doppler tip.
[0040] Certain embodiments include a system for closing a hole in a
targeted tissue, comprising: a closure member having a head and a
plurality of arms extending from the head, the closure member
capable of transitioning between an open position and a closed
position; and a delivery catheter comprising a proximal end, a
distal end, and a hollow tube extending between the proximal end
and the distal end, the delivery catheter configured such that the
closure member is capable of insertion into the hollow tube when
the closure member is in the open position. In at least some
embodiments, the system further comprises an engagement catheter
comprising a proximal end, a distal end, a first lumen extending
between the proximal end and the distal end, and a vacuum port
operatively connected to the first lumen of the engagement catheter
at the proximal end of the engagement catheter, the vacuum port
being capable of operative connection to a vacuum source, wherein
the first lumen of the engagement catheter includes a suction port
located at or near the distal end of the engagement catheter, the
suction port configured to removably attach to a targeted tissue on
the interior of a wall of the heart, such that the suction port is
capable of forming a reversible seal with the targeted tissue when
a vacuum source is operatively attached to the vacuum port; wherein
the delivery catheter is configured for inserted into the first
lumen of the engagement catheter.
[0041] The plurality of arms of the closure member may comprise
nitinol. In some embodiments, the plurality of arms of the closure
member comprise four arms.
[0042] In at least certain embodiments, a method for closing a hole
in a targeted tissue of a heart, the method comprises: providing a
closure member having a head and a plurality of arms extending from
the head, the closure member capable of transitioning between an
open position and a closed position; delivering the closure member
to the heart through a delivery catheter comprising a proximal end,
a distal end, and a hollow tube extending between the proximal end
and the distal end, the delivery catheter configured such that the
closure member is capable of insertion into the hollow tube when
the closure member is in the open position; deploying the closure
member such that the closure member contacts the targeted tissue
and transitions to the closed position. The step of delivery the
closure member to the heart may comprise advancing the closure
member through the delivery catheter by pushing on the head of the
closure member using a rod inserted into the hollow tube.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] FIG. 1A shows an embodiment of an engagement catheter and an
embodiment of a delivery catheter as disclosed herein;
[0044] FIG. 1B shows a percutaneous intravascular pericardial
delivery using another embodiment of an engagement catheter and
another embodiment of a delivery catheter as disclosed herein;
[0045] FIG. 2A shows a percutaneous intravascular technique for
accessing the pericardial space through a right atrial wall or
atrial appendage using the engagement and delivery catheters shown
in FIG. 1A;
[0046] FIG. 2B shows the embodiment of an engagement catheter shown
in FIG. 2A;
[0047] FIG. 2C shows another view of the distal end of the
engagement catheter embodiment shown in FIGS. 2A and 2B;
[0048] FIG. 3A shows removal of an embodiment of a catheter as
disclosed herein;
[0049] FIG. 3B shows the resealing of a puncture according to an
embodiment as disclosed herein;
[0050] FIG. 4A to 4C show a closure of a hole in the atrial wall
using an embodiment as disclosed herein;
[0051] FIG. 4D shows another closure of a hole in cardiac tissue
using another embodiment as disclosed herein;
[0052] FIG. 4E shows yet another closure of a hole in cardiac
tissue using another embodiment as disclosed herein;
[0053] FIG. 4F shows still another closure of a hole in cardiac
tissue using another embodiment as disclosed herein;
[0054] FIG. 5A shows an embodiment of an engagement catheter as
disclosed herein;
[0055] FIG. 5B shows a cross-sectional view of the proximal end of
the engagement catheter shown in FIG. 5A;
[0056] FIG. 5C shows a cross-sectional view of the distal end of
the engagement catheter shown in FIG. 5A;
[0057] FIG. 5D shows the engagement catheter shown in FIG. 5A
approaching a heart wall from inside of the heart;
[0058] FIG. 6A shows an embodiment of a delivery catheter as
disclosed herein;
[0059] FIG. 6B shows a close-up view of the needle shown in FIG.
6A;
[0060] FIG. 6C shows a cross-sectional view of the needle shown in
FIGS. 6A and 6B;
[0061] FIG. 7 shows an embodiment of a delivery catheter as
disclosed herein;
[0062] FIG. 8 shows an embodiment of a steering wire system within
a steering channel;
[0063] FIG. 9A shows another embodiment of a steering wire system
as disclosed herein, the embodiment being deflected in one
location;
[0064] FIG. 9B shows the steering wire system shown in FIG. 9A,
wherein the steering wire system is deflected at two locations;
[0065] FIG. 9C shows the steering wire system shown in FIGS. 9A and
9B in its original position;
[0066] FIG. 10 shows a portion of another embodiment of a steering
wire system;
[0067] FIG. 11 shows a cross-sectional view of another embodiment
of a delivery catheter as disclosed herein;
[0068] FIG. 12A shows an embodiment of a system for closing a hole
in cardiac tissue, as disclosed herein;
[0069] FIG. 12B shows another embodiment of a system for closing a
hole in cardiac tissue, as disclosed herein;
[0070] FIG. 12C shows another embodiment of a system for closing a
hole in cardiac tissue, as disclosed herein;
[0071] FIG. 13 shows another embodiment of a system for closing a
hole in cardiac tissue, as disclosed herein;
[0072] FIG. 14 shows another embodiment of a system for closing a
hole in cardiac tissue, as disclosed herein;
[0073] FIG. 15A shows another embodiment of a system for closing a
hole in cardiac tissue, as disclosed herein;
[0074] FIG. 15B shows the embodiment of FIG. 15A approaching
cardiac tissue; and
[0075] FIG. 15C shows the embodiment of FIGS. 15A-15C deployed on
the cardiac tissue.
DETAILED DESCRIPTION
[0076] For the purposes of promoting an understanding of the
principles of the present disclosure, reference will now be made to
the embodiments illustrated in the drawings, and specific language
will be used to describe the same. It will nevertheless be
understood that no limitation of the scope of this disclosure is
thereby intended.
[0077] The disclosed embodiments include devices, systems, and
methods useful for accessing various tissues of the heart from
inside the heart. For example, various embodiments provide for
percutaneous, intravascular access into the pericardial space
through an atrial wall or the wall of an atrial appendage. In at
least some embodiments, the heart wall is aspirated and retracted
from the pericardial sac to increase the pericardial space between
the heart and the sac and thereby facilitate access into the
space.
[0078] Unlike the relatively stiff pericardial sac, the atrial wall
and atrial appendage are rather soft and deformable. Hence, suction
of the atrial wall or atrial appendage can provide significantly
more clearance of the cardiac structure from the pericardium as
compared to suction of the pericardium. Furthermore, navigation
from the intravascular region (inside of the heart) provides more
certainty of position of vital cardiac structures than does
intrathoracic access (outside of the heart).
[0079] Access to the pericardial space may be used for
identification of diagnostic markers in the pericardial fluid; for
pericardiocentesis; and for administration of therapeutic factors
with angiogenic, myogenic, and antiarrhythmic potential. In
addition, as explained in more detail below, epicardial pacing
leads may be delivered via the pericardial space, and an ablation
catheter may be used on the epicardial tissue from the pericardial
space.
[0080] In the embodiment of the catheter system shown in FIG. 1A,
catheter system 10 includes an engagement catheter 20, a delivery
catheter 30, and a needle 40. Although each of engagement catheter
20, delivery catheter 30, and needle 40 has a proximal end and a
distal end, FIG. 1A shows only the distal end. Engagement catheter
20 has a lumen through which delivery catheter 30 has been
inserted, and delivery catheter 30 has a lumen through which needle
40 has been inserted. Delivery catheter 30 also has a number of
openings 50 that can be used to transmit fluid from the lumen of
the catheter to the heart tissue in close proximity to the distal
end of the catheter.
[0081] As shown in more detail in FIGS. 2A, 2B, 2C, engagement
catheter 20 includes a vacuum channel 60 used for suction of a
targeted tissue 65 in the heart and an injection channel 70 used
for infusion of substances to targeted tissue 65, including, for
example, a biological or non-biological degradable adhesive. As is
shown in FIGS. 2B and 2C, injection channel 70 is ring-shaped,
which tends to provide relatively even dispersal of the infused
substance over the targeted tissue, but other shapes of injection
channels may be suitable. A syringe 80 is attached to injection
channel 70 for delivery of the appropriate substances to injection
channel 70, and a syringe 90 is attached to vacuum channel 60
through a vacuum port (not shown) at the proximal end of engagement
catheter 20 to provide appropriate suction through vacuum channel
60. At the distal end of engagement catheter 20, a suction port 95
is attached to vacuum channel 60 for contacting targeted tissue 65,
such that suction port 95 surrounds targeted tissue 65, which is
thereby encompassed within the circumference of suction port 95.
Although syringe 90 is shown in FIG. 2B as the vacuum source
providing suction for engagement catheter 20, other types of vacuum
sources may be used, such as a controlled vacuum system providing
specific suction pressures. Similarly, syringe 80 serves as the
external fluid source in the embodiment shown in FIG. 2B, but other
external fluid sources may be used.
[0082] A route of entry for use of various embodiments disclosed
herein is through the jugular or femoral vein to the superior or
inferior vena cavae, respectively, to the right atrial wall or
atrial appendage (percutaneously) to the pericardial sac (through
puncture).
[0083] Referring now to FIG. 1B, an engagement catheter 100 is
placed via standard approach into the jugular or femoral vein. The
catheter, which may be 4 or 5 Fr., is positioned under fluoroscopic
or echocardiographic guidance into the right atrial appendage 110.
Suction is initiated to aspirate a portion of atrial appendage 110
away from the pericardial sac 120 that surrounds the heart. As
explained herein, aspiration of the heart tissue is evidenced when
no blood can be pulled back through engagement catheter 100 and, if
suction pressure is being measured, when the suction pressure
gradually increases. A delivery catheter 130 is then inserted
through a lumen of engagement catheter 100. A small perforation can
be made in the aspirated atrial appendage 110 with a needle such as
needle 40, as shown in FIGS. 1A and 2A. A guide wire (not shown)
can then be advanced through delivery catheter 130 into the
pericardial space to secure the point of entry 125 through the
atrial appendage and guide further insertion of delivery catheter
130 or another catheter. Flouroscopy or echocardiogram can be used
to confirm the position of the catheter in the pericardial space.
Alternatively, a pressure tip needle can sense the pressure and
measure the pressure change from the atrium (about 10 mmHg) to the
pericardial space (about 2 mmHg). This is particularly helpful for
transeptal access where puncture of arterial structures (e.g., the
aorta) can be diagnosed and sealed with an adhesive, as described
in more detail below.
[0084] Although aspiration of the atrial wall or the atrial
appendage retracts the wall or appendage from the pericardial sac
to create additional pericardial space, CO2 gas can be delivered
through a catheter, such as delivery catheter 130, into the
pericardial space to create additional space between the
pericardial sac and the heart surface.
[0085] Referring now to FIG. 3A, the catheter system shown in FIG.
1B is retrieved by pull back through the route of entry. However,
the puncture of the targeted tissue in the heart (e.g., the right
atrial appendage as shown in FIG, 3A) may be sealed upon withdrawal
of the catheter, which prevents bleeding into the pericardial
space. The retrieval of the catheter may be combined with a sealing
of the tissue in one of several ways: (1) release of a tissue
adhesive or polymer 75 via injection channel 70 to seal off the
puncture hole, as shown in FIG. 3B; (2) release of an inner clip or
mechanical stitch to close off the hole from the inside of the
cavity or the heart, as discussed herein; or (3) mechanical closure
of the heart with a sandwich type mechanical device that approaches
the hole from both sides of the wall (see FIGS. 4A, 4B, and 4C). In
other words, closure may be accomplished by using, for example, a
biodegradable adhesive material (e.g., fibrin glue or
cyanomethacrylate), a magnetic system, or an umbrella-shaped
nitinol stent. An example of the closure of a hole in the atrium is
shown in FIG. 3B. Engagement catheter 20 is attached to targeted
tissue 95 using suction through suction port 60. Tissue adhesive 75
is injected through injection channel 70 to coat and seal the
puncture wound in targeted tissue 95. Engagement catheter 20 is
then withdrawn, leaving a plug of tissue adhesive 75 attached to
the atrial wall or atrial appendage.
[0086] Other examples for sealing the puncture wound in the atrial
wall or appendage are shown in FIGS. 4A-4F. Referring now to FIGS.
4A-4C, a sandwich-type closure member, having an external cover 610
and an internal cover 620, is inserted through the lumen of
engagement catheter 600, which is attached to the targeted tissue
of an atrial wall 630. Each of external and internal covers 610 and
620 is similar to an umbrella in that it can be inserted through a
catheter in its folded configuration and expanded to an expanded
configuration once it is outside of the catheter. As shown in FIG.
4A, external cover 610 is deployed (in its expanded configuration)
on the outside of the atrial wall to seal a puncture wound in the
targeted tissue, having already been delivered through the puncture
wound into the pericardial space. Internal cover 620 is delivered
through engagement catheter 600 (in its folded configuration), as
shown in FIGS, 4A and 4B, by an elongated delivery wire 615, to
which internal cover 620 is reversibly attached (for example, by a
screw-like mechanism). Once internal cover 620 is in position on
the inside of atrial wall 630 at the targeted tissue, internal
cover 620 is deployed to help seal the puncture wound in the
targeted tissue (see FIG. 4C).
[0087] Internal cover 620 and external cover 610 may be made from a
number of materials, including a shape-memory alloy such as
nitinol. Such embodiments are capable of existing in a catheter in
a folded configuration and then expanding to an expanded
configuration when deployed into the body. Such a change in
configuration can result from a change in temperature, for example.
Other embodiments of internal and external covers may be made from
other biocompatible materials and deployed mechanically.
[0088] After internal cover 620 is deployed, engagement catheter
600 releases its grip on the targeted tissue and is withdrawn,
leaving the sandwich-type closure to seal the puncture wound, as
shown in FIG. 4C. External cover 610 and internal cover 620 may be
held in place using a biocompatible adhesive. Similarly, external
cover 610 and internal cover 620 may be held in place using
magnetic forces, such as, for example, by the inside face (not
shown) of external cover 610 comprising a magnet, by the inside
face (not shown) of internal cover 620 comprising a magnet, or both
inside faces of external cover 610 or internal cover 620 comprising
magnets.
[0089] In the embodiment shown in FIGS. 4A, 4B, and 4C, the closure
member comprises external cover 610 and internal cover 620.
However, in at least certain other embodiments, the closure member
need not have two covers. For example, as shown in FIG. 4D, closure
member 632 is made of only one cover 634. Cover 634 has a first
face 636 and a second face 638, and first face 636 is configured
for reversible attachment to distal end 642 of delivery wire 640.
Closure member 632 may be made of any suitable material, including
nitinol, which is capable of transitioning from a folded
configuration to an expanded configuration.
[0090] In the embodiment shown in FIG. 4E, a closure member 1500
comprises an external cover 1510 and an internal cover 1520 within
a delivery catheter 1530. External cover 1510 and internal cover
1520 are attached at a joint 1540, which may be formed, for
example, by a mechanical attachment or by a magnetic attachment. In
embodiments having a magnetic attachment, each of the external
cover and the internal cover may have a ferromagnetic component
that is capable of magnetically engaging the other ferromagnetic
component.
[0091] Delivery catheter 1530 is shown after insertion through hole
1555 of atrial wall 1550. Closure member 1500 may be advanced
through delivery catheter 1530 to approach atrial wall 1550 by
pushing rod 1560. Rod 1560 may be reversibly attached to internal
cover 1520 so that rod 1560 may be disconnected from internal cover
1520 after closure member 1500 is properly deployed. For example,
rod 1560 may engage internal cover 1520 with a screw-like tip such
that rod 1560 may be easily unscrewed from closure member 1500
after deployment is complete. Alternatively, rod 1560 may simply
engage internal cover 1520 such that internal cover 1520 may be
pushed along the inside of delivery catheter 1530 without
attachment between internal cover 1520 and rod 1560.
[0092] Closure member 1500 is advanced through delivery catheter
1530 until external cover 1510 reaches a portion of delivery
catheter 1530 adjacent to atrial wall 1550; external cover 1510 is
then pushed slowly out of delivery catheter 1530 into the
pericardial space. External cover 1510 then expands and is
positioned on the outer surface of atrial wall 1550. When external
cover 1510 is properly positioned on atrial wall 1550, joint 1540
is approximately even with atrial wall 1550 within hole 1555.
Delivery catheter 1530 is then withdrawn slowly, causing hole 1555
to close slightly around joint 1540. As delivery catheter 1530
continues to be withdrawn, internal cover 1520 deploys from
delivery catheter 1530, thereby opening into its expanded
formation. Consequently, atrial wall 1550 is pinched between
internal cover 1520 and external cover 1510, and hole 1555 is
closed to prevent leakage of blood from the heart.
[0093] FIG. 4F shows the occlusion of a hole (not shown) in atrial
wall 1600 due to the sandwiching of atrial wall 1600 between an
external cover 1610 and an internal cover 1620. External cover 1610
is shown deployed on the outside surface of atrial wall 1600, while
internal cover 1620 is deployed on the inside surface of atrial
wall 1600. As shown, rod 1640 is engaged with internal cover 1620,
and delivery catheter 1630 is in the process of being withdrawn,
which allows internal cover 1620 to fully deploy. Rod 1640 is then
withdrawn through delivery catheter 1630. An engagement catheter
(not shown) may surround delivery catheter 1650, as explained more
fully herein.
[0094] Other examples for sealing a puncture wound in the cardiac
tissue are shown in FIGS. 12-15. Referring now to FIG. 12A, there
is shown a plug 650 having a first end 652, a second end 654, and a
hole 656 extending from first end 652 to second end 654. Plug 650
may be made from any suitable material, including casein,
polyurethane, silicone, and polytetrafluoroethylene. Wire 660 has
been slidably inserted into hole 656 of plug 650. Wire 660 may be,
for example, a guide wire or a pacing lead, so long as it extends
through the hole in the cardiac tissue (not shown). As shown in
FIG. 12A, first end 652 is covered with a radiopaque material, such
as barium sulfate, and is therefore radiopaque. This enables the
clinician to view the placement of the plug in the body using
radiographic imaging. For example, the clinician can confirm the
location of the plug during the procedure, enabling a safer and
more effective procedure for the patient.
[0095] As shown in FIG. 12A, first end 652 of plug 650 has a
smaller diameter than second end 654 of plug 650. Indeed, plug 680
shown FIG. 12B and plug 684 shown in FIGS. 13 and 14 have first
ends that are smaller in diameter than their respective second
ends. However, not all embodiments of plug have a first end that is
smaller in diameter than the second end. For example, plug 682
shown in FIG. 12C has a first end with a diameter that is not
smaller than the diameter of the second end. Both types of plug can
be used to close holes in cardiac tissue.
[0096] Referring again to FIG. 12A, elongated shaft 670 has a
proximal end (not shown), a distal end 672, and a lumen 674
extending from the proximal end to distal end 672. Although no
catheter is shown in FIG. 12A, plug 650, wire 660, and shaft 670
are configured for insertion into a lumen of a catheter (see FIG.
14), such as an embodiment of an engagement catheter disclosed
herein. Plug 650 and shaft 670 are also configured to be inserted
over wire 660 and can slide along wire 660 because each of lumen
656 of plug 650 and lumen 674 of shaft 670 is slightly larger in
circumference than wire 660.
[0097] As shown in FIGS. 13 and 14, shaft 672 is used to push plug
684 along wire 674 within elongated tube 676 to and into the hole
in the targeted cardiac tissue 678. Distal end 677 of elongated
tube 676 is shown attached to cardiac tissue 678, but distal end
677 need not be attached to cardiac tissue 678 so long as distal
end 677 is adjacent to cardiac tissue 678. Once plug 684 is
inserted into the hole, wire 674 may be withdrawn from the hole in
plug 684 and the interior of the heart (not shown) and shaft 672 is
withdrawn from elongated tube 676. In some embodiments, the plug is
self-sealing, meaning that the hole of the plug closes after the
wire is withdrawn. For example, the plug may be made from a
dehydrated protein matrix, such as casein or ameroid, which swells
after soaking up fluid. After shaft 672 is withdrawn, elongated
tube 676 can be withdrawn from the heart.
[0098] It should be noted that, in some embodiments, the wire is
not withdrawn from the hole of the plug. For example, where the
wire is a pacing lead, the wire may be left within the plug so that
it operatively connects to the CRT device.
[0099] Referring now to FIG. 12B, there is shown a plug 680 that is
similar to plug 684. However, plug 680 comprises external surface
681 having a ridge 683 that surrounds plug 680 in a helical or
screw-like shape. Ridge 683 helps to anchor plug 680 into the hole
of the targeted tissue (not shown). Other embodiments of plug may
include an external surface having a multiplicity of ridges
surrounding the plug, for example, in a circular fashion.
[0100] FIGS. 15A-15C show yet another embodiment of a closure
member for closing a hole in a tissue. Spider clip 1700 is shown
within catheter 1702 and comprises a head 1705 and a plurality of
arms 1710, 1720, 1730, and 1740. Each of arms 1710, 1720, 1730, and
1740 is attached at its proximal end to head 1705. Although spider
clip 1700 has four arms, other embodiments of spider clip include
fewer than, or more than, four arms. For example, some embodiments
of spider clip have three arms, while others have five or more
arms.
[0101] Referring again to FIGS. 15A-15C, arms 1710, 1720, 1730, and
1740 may be made from any flexible biocompatible metal that can
transition between two shapes, such as a shape-memory alloy (e.g.,
nitinol) or stainless steel. Spider clip 1700 is capable of
transitioning between an open position (see FIG. 15A), in which the
distal ends of its arms 1710, 1720, 1730, and 1740 are spaced
apart, and a closed position (see FIG. 15C), in which the distal
ends of arms 1710, 1720, 1730, and 1740 are gathered together. For
embodiments made from a shape-memory alloy, the clip can be
configured to transition from the open position to the closed
position when the metal is warmed to approximately body
temperature, such as when the clip is placed into the cardiac
tissue. For embodiments made from other types of metal, such as
stainless steel, the clip is configured in its closed position, but
may be transitioned into an open position when pressure is exerted
on the head of the clip. Such pressure causes the arms to bulge
outward, thereby causing the distal ends of the arms to
separate.
[0102] In this way, spider clip 1700 may be used to seal a wound or
hole in a tissue, such as a hole through the atrial wall. For
example, FIG. 15B shows spider clip 1700 engaged by rod 1750 within
engagement catheter 1760. As shown, engagement catheter 1760 has a
bell-shaped suction port 1765, which, as disclosed herein, has
aspirated cardiac tissue 1770. Cardiac tissue 1770 includes a hole
1775 therethrough, and suction port 1765 fits over hole 1775 so as
to expose hole 1775 to spider clip 1700.
[0103] Rod 1750 pushes spider clip 1700 through engagement catheter
1760 to advance spider clip 1700 toward cardiac tissue 1770. Rod
1750 simply engages head 1705 by pushing against it, but in other
embodiments, the rod may be reversibly attached to the head using a
screw-type system. In such embodiments, the rod may be attached and
detached from the head simply by screwing the rod into, or
unscrewing the rod out of the head, respectively.
[0104] In at least some embodiments, the spider clip is held in its
open position during advancement through the engagement catheter by
the pressure exerted on the head of the clip by the rod. This
pressure may be opposed by the biasing of the legs against the
engagement catheter during advancement.
[0105] Referring to FIG, 15C, spider clip 1700 approaches cardiac
tissue 1770 and eventually engages cardiac tissue 1770 such that
the distal end of each of arms 1710, 1720, 1730, and 1740 contacts
cardiac tissue 1770. Rod 1750 is disengaged from spider clip 1700,
and spider clip 1700 transitions to its closed position, thereby
drawing the distal ends of arms 1710, 1720, 1730, and 1740
together. As the distal ends of the arms are drawn together, the
distal ends grip portions of cardiac tissue 1770, thereby
collapsing the tissue between arms 1710, 1720, 1730, and 1740 such
that hole 1775 is effectively closed.
[0106] Rod 1750 is then withdrawn, and engagement catheter 1760 is
disengaged from cardiac tissue 1770. The constriction of cardiac
tissue 1770 holds hole 1775 closed so that blood does not leak
through hole 1775 after engagement catheter 1760 is removed. After
a relatively short time, the body's natural healing processes
permanently close hole 1775. Spider clip 1700 may remain in the
body indefinitely.
[0107] Referring now to FIGS. 5A, 5B, 5C, and 5D, there is shown
another embodiment of an engagement catheter as disclosed herein.
Engagement catheter 700 is an elongated tube having a proximal end
710 and a distal end 720, as well as two lumens 730, 740 extending
between proximal end 710 and distal end 720. Lumens 730, 740 are
formed by concentric inner wall 750 and outer wall 760, as
particularly shown in FIGS. 5B and 5C. At proximal end 710,
engagement catheter 700 includes a vacuum port 770, which is
attached to lumen 730 so that a vacuum source can be attached to
vacuum port 770 to create suction in lumen 730, thereby forming a
suction channel. At distal end 720 of catheter 700, a suction port
780 is attached to lumen 730 so that suction port 780 can be placed
in contact with heart tissue 775 (see FIG. 5D) for aspirating the
tissue, thereby forming a vacuum seal between suction port 780 and
tissue 775 when the vacuum source is attached and engaged. The
vacuum seal enables suction port 780 to grip, stabilize, and
retract tissue 775. For example, attaching a suction port to an
interior atrial wall using a vacuum source enables the suction port
to retract the atrial wall from the pericardial sac surrounding the
heart, which enlarges the pericardial space between the atrial wall
and the pericardial sac.
[0108] As shown in FIG. 5C, two internal lumen supports 810, 820
are located within lumen 730 and are attached to inner wall 750 and
outer wall 760 to provide support to the walls. These lumen
supports divide lumen 730 into two suction channels. Although
internal lumen supports 810, 820 extend from distal end 720 of
catheter 700 along a substantial portion of the length of catheter
700, internal lumen supports 810, 820 may or may not span the
entire length of catheter 700. Indeed, as shown in FIGS. 5A, 5B,
and 5C, internal lumen supports 810, 820 do not extend to proximal
end 710 to ensure that the suction from the external vacuum source
is distributed relatively evenly around the circumference of
catheter 700. Although the embodiment shown in FIG. 5C includes two
internal lumen supports, other embodiments may have just one
internal support or even three or more such supports.
[0109] FIG. 5D shows engagement catheter 700 approaching heart
tissue 775 for attachment thereto. It is important for the
clinician performing the procedure to know when the suction port
has engaged the tissue of the atrial wall or the atrial appendage.
For example, in reference to FIG. 5D, it is clear that suction port
780 has not fully engaged tissue 775 such that a seal is formed.
However, because suction port 780 is not usually seen during the
procedure, the clinician may determine when the proper vacuum seal
between the atrial tissue and the suction port has been made by
monitoring the amount of blood that is aspirated, by monitoring the
suction pressure with a pressure sensor/regulator, or both. For
example, as engagement catheter 700 approaches the atrial wall
tissue (such as tissue 775) and is approximately in position, the
suction can be activated through lumen 730. A certain level of
suction (e.g., 10 mmHg) can be imposed and measured with a pressure
sensor/regulator. As long as catheter 700 does not engage the wall,
some blood will be aspirated into the catheter and the suction
pressure will remain the same. However, when catheter 700 engages
or attaches to the wall of the heart (depicted as tissue 775 in
FIG. 5D), minimal blood is aspirated and the suction pressure will
start to gradually increase. Each of these signs can alert the
clinician (through alarm or other means) as an indication of
engagement. The pressure regulator is then able to maintain the
suction pressure at a preset value to prevent over-suction of the
tissue.
[0110] An engagement catheter, such as engagement catheter 700, may
be configured to deliver a fluid or other substance to tissue on
the inside of a wall of the heart, including an atrial wall or a
ventricle wall. For example, lumen 740 shown in FIGS. 5A and 5C
includes an injection channel 790 at distal end 720. Injection
channel 790 dispenses to the targeted tissue a substance flowing
through lumen 740. As shown in FIG. 5D, injection channel 790 is
the distal end of lumen 740. However, in other embodiments, the
injection channel may be ring-shaped (see FIG. 2C) or have some
other suitable configuration.
[0111] Substances that can be locally administered with an
engagement catheter include preparations for gene or cell therapy,
drugs, and adhesives that are safe for use in the heart. The
proximal end of lumen 740 has a fluid port 800, which is capable of
attachment to an external fluid source for supply of the fluid to
be delivered to the targeted tissue. Indeed, after withdrawal of a
needle from the targeted tissue, as discussed herein, an adhesive
may be administered to the targeted tissue by the engagement
catheter for sealing the puncture wound left by the needle
withdrawn from the targeted tissue.
[0112] Referring now to FIGS. 6A, 6B, and 6C, there is shown a
delivery catheter 850 comprising an elongated hollow tube 880
having a proximal end 860, a distal end 870, and a lumen 885 along
the length of the catheter. Extending from distal end 870 is a
hollow needle 890 in communication with lumen 885. Needle 890 is
attached to distal end 870 in the embodiment of FIGS. 6A, 6B, and
6C, but, in other embodiments, the needle may be removably attached
to, or otherwise located at, the distal end of the catheter (see
FIG, 1A). In the embodiment shown in FIGS. 6A, 6B, and 6C, as in
certain other embodiments having an attached needle, the junction
(i.e., site of attachment) between hollow tube 880 and needle 890
forms a security notch 910 circumferentially around needle 890 to
prevent needle 890 from over-perforation. Thus, when a clinician
inserts needle 890 through an atrial wall to gain access to the
pericardial space, the clinician will not, under normal conditions,
unintentionally perforate the pericardial sac with needle 890
because the larger diameter of hollow tube 880 (as compared to that
of needle 890) at security notch 910 hinders further needle
insertion. Although security notch 910 is formed by the junction of
hollow tube 880 and needle 890 in the embodiment shown in FIGS, 6A,
6B, and 6C, other embodiments may have a security notch that is
configured differently. For example, a security notch may include a
band, ring, or similar device that is attached to the needle a
suitable distance from the tip of the needle. Like security notch
910, other security notch embodiments hinder insertion of the
needle past the notch itself by presenting a larger profile than
the profile of the needle such that the notch does not easily enter
the hole in the tissue caused by entry of the needle.
[0113] It is useful for the clinician performing the procedure to
know when the needle has punctured the atrial tissue. This can be
done in several ways. For example, the delivery catheter can be
connected to a pressure transducer to measure pressure at the tip
of the needle. Because the pressure is lower and much less
pulsatile in the pericardial space than in the atrium, the
clinician can recognize immediately when the needle passes through
the atrial tissue into the pericardial space.
[0114] Alternatively, as shown in FIG. 6B, needle 890 may be
connected to a strain gauge 915 as part of the catheter assembly.
When needle 890 contacts tissue (not shown), needle 890 will be
deformed. The deformation will be transmitted to strain gauge 915
and an electrical signal will reflect the deformation (through a
classical wheatstone bridge), thereby alerting the clinician. Such
confirmation of the puncture of the wall can prevent over-puncture
and can provide additional control of the procedure.
[0115] In some embodiments, a delivery catheter, such as catheter
850 shown in FIGS. 6A, 6B, and 6C, is used with an engagement
catheter, such as catheter 700 shown in FIGS. 5A, 5B, 5C, and 5D,
to gain access to the pericardial space between the heart wall and
the pericardial sac. For example, engagement catheter 700 may be
inserted into the vascular system and advanced such that the distal
end of the engagement catheter is within the atrium. The engagement
catheter may be attached to the targeted tissue on the interior of
a wall of the atrium using a suction port as disclosed herein. A
standard guide wire may be inserted through the lumen of the
delivery catheter as the delivery catheter is inserted through the
inner lumen of the engagement catheter, such as lumen 740 shown in
FIGS. 5B and 5C. Use of the guide wire enables more effective
navigation of the delivery catheter 850 and prevents the needle 890
from damaging the inner wall 750 of the engagement catheter 700.
When the tip of the delivery catheter with the protruding guide
wire reaches the atrium, the wire is pulled back, and the needle is
pushed forward to perforate the targeted tissue. The guide wire is
then advanced through the perforation into the pericardial space,
providing access to the pericardial space through the atrial
wall.
[0116] Referring again to FIGS, 6A, 6B, and 6C, lumen 885 of
delivery catheter 850 may be used for delivering fluid into the
pericardial space after needle 890 is inserted through the atrial
wall or the atrial appendage. After puncture of the wall or
appendage, a guide wire (not shown) may be inserted through needle
lumen 900 into the pericardial space to maintain access through the
atrial wall or appendage. Fluid may then be introduced to the
pericardial space in a number of ways. For example, after the
needle punctures the atrial wall or appendage, the needle is
generally withdrawn. If the needle is permanently attached to the
delivery catheter, as in the embodiment shown in FIGS. 6A and 6B,
then delivery catheter 850 would be withdrawn and another delivery
catheter (without an attached needle) would be introduced over the
guide wire into the pericardial space. Fluid may then be introduced
into the pericardial space through the lumen of the second delivery
catheter,
[0117] In some embodiments, however, only a single delivery
catheter is used. In such embodiments, the needle is not attached
to the delivery catheter, but instead may be a needle wire (see
FIG. 1A). In such embodiments, the needle is withdrawn through the
lumen of the delivery catheter, and the delivery catheter may be
inserted over the guide wire into the pericardial space. Fluid is
then introduced into the pericardial space through the lumen of the
delivery catheter.
[0118] The various embodiments disclosed herein may be used by
clinicians, for example: (1) to deliver genes, cells, drugs, etc.;
(2) to provide catheter access for epicardial stimulation; (3) to
evacuate fluids acutely (e.g., in cases of pericardial tampondae)
or chronically (e.g., to alleviate effusion caused by chronic renal
disease, cancer, etc.); (4) to perform transeptal puncture and
delivery of a catheter through the left atrial appendage for
electrophysiological therapy, biopsy, etc.; (5) to deliver a
magnetic glue or ring through the right atrial appendage to the
aortic root to hold a percutaneous aortic valve in place; (6) to
deliver a catheter for tissue ablation, e.g., to the pulmonary
veins, or right atrial and epicardial surface of the heart for
atrial and ventricular arrythmias; (7) to deliver and place
epicardial, right atrial, and right and left ventricle pacing leads
(as discussed herein); (8) to occlude the left atrial appendage
through percutaneous approach; and (9) to visualize the pericardial
space with endo-camera or scope to navigate the epicardial surface
of the heart for therapeutic delivery, diagnosis, lead placement,
mapping, etc. Many other applications, not explicitly listed here,
are also possible and within the scope of the present
disclosure.
[0119] Referring now to FIG. 7, there is shown a delivery catheter
1000. Delivery catheter 1000 includes an elongated tube 1010 having
a wall 1020 extending from a proximal end (not shown) of tube 1010
to a distal end 1025 of tube 1010. Tube 1010 includes two lumens,
but other embodiments of delivery catheters may have fewer than, or
more than, two lumens, depending on the intended use of the
delivery catheter. Tube 1010 also includes a steering channel 1030,
in which a portion of steering wire system 1040 is located.
Steering channel 1030 forms orifice 1044 at distal end 1025 of tube
1010 and is sized to fit over a guide wire 1050.
[0120] FIG. 8 shows in more detail steering wire system 1040 within
steering channel 1030 (which is shown cut away from the remainder
of the delivery catheter). Steering wire system 1040 is partially
located in steering channel 1030 and comprises two steering wires
1060 and 1070 and a controller 1080, which, in the embodiment shown
in FIG. 8, comprises a first handle 1090 and a second handle 1094.
First handle 1090 is attached to proximal end 1064 of steering wire
1060, and second handle 1094 is attached to proximal end 1074 of
steering wire 1070. Distal end 1066 of steering wire 1060 is
attached to the wall of the tube of the delivery catheter within
steering channel 1030 at attachment 1100, and distal end 1076 of
steering wire 1070 is attached to the wall of the tube of the
delivery catheter within steering channel 1030 at attachment 1110.
As shown in FIG. 7, attachment 1100 and attachment 1110 are located
on opposing sides of steering channel 1030 near distal tip 1120 of
delivery catheter 1000.
[0121] In the embodiment of FIG. 8, steering wires 1060 and 1070
are threaded as a group through steering channel 1030. However, the
steering wire systems of other embodiments may include steering
wires that are individually threaded through smaller lumens within
the steering channel. For example, FIG. 11 shows a cross-sectional
view of a delivery catheter 1260 having an elongated tube 1264
comprising a wall 1266, a steering channel 1290, a first lumen
1270, and a second lumen 1280. Delivery catheter 1260 further
includes a steering wire 1292 within a steering wire lumen 1293, a
steering wire 1294 within a steering wire lumen 1295, and a
steering wire 1296 within a steering wire lumen 1297. Each of
steering wire lumens 1293, 1295, and 1297 is located within
steering channel 1290 and is formed from wall 1266. Each of
steering wires 1292, 1294, and 1296 is attached to wall 1266 within
steering channel 1290. As will be explained, the attachment of each
steering wire to the wall may be located near the distal tip of the
delivery catheter, or may be located closer to the middle of the
delivery catheter.
[0122] Referring now to FIGS. 7 and 8, steering wire system 1040
can be used to control distal tip 1120 of delivery catheter 1000.
For example, when first handle 1090 is pulled, steering wire 1060
pulls distal tip 1120, which bends delivery catheter 1000, causing
tip deflection in a first direction. Similarly, when second handle
1094 is pulled, steering wire 1070 pulls distal tip 1120 in the
opposite direction, which bends delivery catheter 1000, causing tip
deflection in the opposite direction. Thus, delivery catheter 1000
can be directed (i.e., steered) through the body using steering
wire system 1040.
[0123] Although steering wire system 1040 has only two steering
wires, other embodiments of steering wire systems may have more
than two steering wires. For example, some embodiments of steering
wire systems may have three steering wires (see FIG. 11), each of
which is attached to the steering channel at a different
attachment. Other embodiments of steering wire systems may have
four steering wires. Generally, more steering wires give the
clinician more control for directing the delivery catheter because
each additional steering wire enables the user to deflect the tip
of the delivery catheter in an additional direction. For example,
four steering wires could be used to direct the delivery catheter
in four different directions (e.g., up, down, right, and left).
[0124] If a steering wire system includes more than two steering
wires, the delivery catheter may be deflected at different points
in the same direction. For instance, a delivery catheter with three
steering wires may include two steering wires for deflection in a
certain direction and a third steering wire for reverse deflection
(i.e., deflection in the opposite direction). In such an
embodiment, the two steering wires for deflection are attached at
different locations along the length of the delivery catheter.
Referring now to FIGS. 9A-9C, there is shown a steering wire system
1350 within steering channel 1360 (which is shown cut away from the
remainder of the delivery catheter) in different states of
deflection. Steering wire system 1350 is partially located in
steering channel 1360 and comprises three steering wires 1370,
1380, and 1390 and a controller 1400, which, in the embodiment
shown in FIGS. 9A-9C, comprises a handle 1405. Handle 1405 is
attached to proximal end 1374 of steering wire 1370, proximal end
1384 of steering wire 1380, and proximal end 1394 of steering wire
1390. Distal end 1376 of steering wire 1370 is attached to the wall
of the tube of the delivery catheter within steering channel 1360
at attachment 1378, which is near the distal tip of the delivery
catheter (not shown). Distal end 1386 of steering wire 1380 is
attached to the wall of the tube of the delivery catheter within
steering channel 1360 at attachment 1388, which is near the distal
tip of the delivery catheter (not shown). Attachment 1378 and
attachment 1388 are located on opposing sides of steering channel
1360 such that steering wires 1370 and 1380, when tightened (as
explained below), would tend to deflect the delivery catheter in
opposite directions. Distal end 1396 of steering wire 1390 is
attached to the wall of the tube of the delivery catheter within
steering channel 1360 at attachment 1398, which is located on the
delivery catheter at a point closer to the proximal end of the
delivery catheter than attachments 1378 and 1388. Attachment 1398
is located on the same side of steering channel 1360 as attachment
1388, such that steering wires 1380 and 1390, when tightened (as
explained below), would tend to deflect the delivery catheter in
the same direction. However, because attachment 1398 is closer to
the proximal end of the delivery catheter than is attachment 1388,
the tightening of steering wire 1390 tends to deflect the delivery
catheter at a point closer to the proximal end of the delivery
catheter than does the tightening of steering wire 1380. Thus, as
shown in FIG. 9A, the tightening of steering wire 1390 causes a
deflection in the delivery catheter approximately at point 1410.
The tightening of steering wire 1380 at the same time causes a
further deflection in the delivery catheter approximately at point
1420, as shown in FIG. 9B. The tightening of steering wire 1370,
therefore, causes a reverse deflection, returning the delivery
catheter to its original position (see FIG. 9C).
[0125] Referring again to FIG. 7, elongated tube 1010 further
includes lumen 1130 and lumen 1140. Lumen 1130 extends from
approximately the proximal end (not shown) of tube 1010 to or near
distal end 1025 of tube 1010. Lumen 1130 has a bend 1134, relative
to tube 1010, at or near distal end 1025 of tube 1010 and an outlet
1136 through wall 1020 of tube 1010 at or near distal end 1025 of
tube 1010. Similarly, lumen 1140 has a bend 1144, relative to tube
1010, at or near distal end 1025 of tube 1010 and an outlet 1146
through wall 1020 of tube 1010 at or near distal end 1025 of tube
1010. In the embodiment shown in FIG. 7, lumen 1130 is configured
as a laser Doppler tip, and lumen 1140 is sized to accept a
retractable sensing lead 1150 and a pacing lead 1160 having a tip
at the distal end of the lead. The fiberoptic laser Doppler tip
detects and measures blood flow (by measuring the change in
wavelength of light emitted by the tip), which helps the clinician
to identify--and then avoid--blood vessels during lead placement.
Sensing lead 1150 is designed to detect electrical signals in the
heart tissue so that the clinician can avoid placing a pacing lead
into electrically nonresponsive tissue, such as scar tissue. Pacing
lead 1160 is a screw-type lead for placement onto the cardiac
tissue, and its tip, which is an electrode, has a substantially
screw-like shape. Pacing lead 1160 is capable of operative
attachment to a CRT device (not shown) for heart pacing. Although
lead 1160 is used for cardiac pacing, any suitable types of leads
may be used with the delivery catheters described herein, including
sensing leads.
[0126] Each of bend 1134 of lumen 1130 and bend 1144 of lumen 1140
forms an approximately 90-degree angle, which allows respective
outlets 1136 and 1146 to face the external surface of the heart as
the catheter is maneuvered in the pericardial space. However, other
embodiments may have bends forming other angles, smaller or larger
than 90-degrees, so long as the lumen provides proper access to the
external surface of the heart from the pericardial space. Such
angles may range, for example, from about 25-degrees to about
155-degrees. In addition to delivering leads and Doppler tips,
lumen 1130 and lumen 1140 may be configured to allow, for example,
the taking of a cardiac biopsy, the delivery of gene cell treatment
or pharmacological agents, the delivery of biological glue for
ventricular reinforcement, implementation of ventricular epicardial
suction in the acute myocardial infarction and border zone area,
the removal of fluid in treatment of pericardial effusion or
cardiac tamponade, or the ablation of cardiac tissue in treatment
of atrial fibrillation.
[0127] For example, lumen 1130 could be used to deliver a catheter
needle for intramyocardial injection of gene cells, stems,
biomaterials, growth factors (such as cytokinase, fibroblast growth
factor, or vascular endothelial growth factor) and/or biodegradable
synthetic polymers, ROD-liposome biologic glue, or any other
suitable drug or substance for treatment or diagnosis. For example,
suitable biodegradable synthetic polymer may include polylactides,
polyglycolides, polycaprolactones, polyanhydrides, polyamides, and
polyurethanes. In certain embodiments, the substance comprises a
tissue inhibitor, such as a metalloproteinase (e.g.,
metalloproteinase 1),
[0128] The injection of certain substances (such as biopolymers and
RGD-liposome biologic glue) is useful in the treatment of chronic
heart failure to reinforce and strengthen the left ventricular
wall. Thus, using the embodiments disclosed herein, the injection
of such substances into the cardiac tissue from the pericardial
space alleviates the problems and risks associated with delivery
via the transthoracic approach. For instance, once the distal end
of the delivery catheter is advanced to the pericardial space, as
disclosed herein, a needle is extended through a lumen of the
delivery catheter into the cardiac tissue and the substance is
injected through the needle into the cardiac tissue.
[0129] The delivery of substances into the cardiac tissue from the
pericardial space can be facilitated using a laser Doppler tip. For
example, when treating ventricular wall thinning, the laser Doppler
tip located in lumen 1140 of the embodiment shown in FIG. 7 can be
used to measure the thickness of the left ventricular wall during
the procedure (in real time) to determine the appropriate target
area for injection.
[0130] Referring again to FIG. 8, although controller 1080
comprises first handle 1090 and second handle 1094, other
embodiments of the controller may include different configurations.
For example, instead of using handles, a controller may include any
suitable torque system for controlling the steering wires of the
steering wire system. Referring now to FIG. 10, there is shown a
portion of a steering wire system 1170 having steering wire 1180,
steering wire 1190, and controller 1200. Controller 1200 comprises
a torque system 1210 having a first rotatable spool 1220, which is
capable of collecting and dispensing steering wire 1180 upon
rotation. For example, when first rotatable spool 1220 rotates in a
certain direction, steering wire 1180 is collected onto spool 1220,
thereby tightening steering wire 1180. When spool 1220 rotates in
the opposite direction, steering wire 1180 is dispensed from spool
1220, thereby loosening steering wire 1180. Torque system 1210 also
has a second rotatable spool 1230, which is capable of collecting
and dispensing steering wire 1190 upon rotation, as described
above.
[0131] Torque system 1210 further includes a first rotatable dial
1240 and a second rotatable dial 1250. First rotatable dial 1240 is
attached to first rotatable spool 1220 such that rotation of first
rotatable dial 1240 causes rotation of first rotatable spool 1220.
Similarly, second rotatable dial 1250 is attached to second
rotatable spool 1230 such that rotation of second rotatable dial
1250 causes rotation of second rotatable spool 1230. For ease of
manipulation of the catheter, torque system 1210, and specifically
first and second rotatable dials 1240 and 1250, may optionally be
positioned on a catheter handle (not shown) at the proximal end of
tube 1010.
[0132] Steering wire system 1170 can be used to direct a delivery
catheter through the body in a similar fashion as steering wire
system 1140. Thus, for example, when first rotatable dial 1240 is
rotated in a first direction (e,g., clockwise), steering wire 1180
is tightened and the delivery catheter is deflected in a certain
direction. When first rotatable dial 1240 is rotated in the other
direction (e.g., counterclockwise), steering wire 1180 is loosened
and the delivery catheter straightens to its original position.
When second rotatable dial 1250 is rotated in one direction (e.g.,
counterclockwise), steering wire 1190 is tightened and the delivery
catheter is deflected in a direction opposite of the first
deflection. When second rotatable dial 1250 is rotated in the other
direction (e.g., clockwise), steering wire 1190 is loosened and the
delivery catheter is straightened to its original position.
[0133] Certain other embodiments of steering wire system may
comprise other types of torque system, so long as the torque system
permits the clinician to reliably tighten and loosen the various
steering wires. The magnitude of tightening and loosening of each
steering wire should be controllable by the torque system,
[0134] Referring again to FIG. 11, there is shown a cross-sectional
view of delivery catheter 1260. Delivery catheter 1260 includes
tube 1265, a first lumen 1270, a second lumen 1280, and a steering
channel 1290. Steering wires 1292, 1294, and 1296 are shown within
steering channel 1290. First lumen 1270 has outlet 1275, which can
be used to deliver a micro-camera system (not shown) or a laser
Doppler tip 1278. Second lumen 1280 is sized to deliver a pacing
lead 1300, as well as a sensing lead (not shown).
[0135] A pacing lead may be placed on the external surface of the
heart using an engagement catheter and a delivery catheter as
disclosed herein. For example, an elongated tube of an engagement
catheter is extended into a blood vessel so that the distal end of
the tube is in contact with a targeted tissue on the interior of a
wall of the heart. As explained above, the targeted tissue may be
on the interior of the atrial wall or the atrial appendage. Suction
is initiated to aspirate a portion of the targeted tissue to
retract the cardiac wall away from the pericardial sac that
surrounds the heart, thereby enlarging a pericardial space between
the pericardial sac and the cardiac wall. A needle is then inserted
through a lumen of the tube and advanced to the heart. The needle
is inserted into the targeted tissue, causing a perforation of the
targeted tissue. The distal end of a guide wire is inserted through
the needle into the pericardial space to secure the point of entry
through the cardiac wall. The needle is then withdrawn from the
targeted tissue.
[0136] A delivery catheter, as described herein, is inserted into
the lumen of the tube of the engagement catheter and over the guide
wire. The delivery catheter may be a 14 Fr. radiopaque steering
catheter. The distal end of the delivery catheter is advanced over
the guide wire through the targeted tissue into the pericardial
space. Once in the pericardial space, the delivery catheter is
directed using a steering wire system as disclosed herein. In
addition, a micro-camera system may be extended through the lumen
of the delivery catheter to assist in the direction of the delivery
catheter to the desired location in the pericardial space.
Micro-camera systems suitable for use with the delivery catheter
are well-known in the art. Further, a laser Doppler system may be
extended through the lumen of the delivery catheter to assist in
the direction of the delivery catheter. The delivery catheter is
positioned such that the outlet of one of the lumens of the
delivery catheter is adjacent to the external surface of the heart
(e.g., the external surface of an atrium or a ventricle). A pacing
lead is extended through the lumen of the delivery catheter onto
the external surface of the heart. The pacing lead may be attached
to the external surface of the heart, for example, by screwing the
lead into the cardiac tissue. In addition, the pacing lead may be
placed deeper into the cardiac tissue, for example in the
subendocardial tissue, by screwing the lead further into the
tissue. After the lead is placed in the proper position, the
delivery catheter is withdrawn from the pericardial space and the
body. The guide wire is withdrawn from the pericardial space and
the body, and the engagement catheter is withdrawn from the
body.
[0137] The disclosed embodiments can be used for subendocardial, as
well as epicardial, pacing. While the placement of the leads is
epicardial, the leads can be configured to have a long screw-like
tip that reaches near the subendocardial wall. The tip of the lead
can be made to be conducting and stimulatory to provide the pacing
to the subendocardial region. In general, the lead length can be
selected to pace transmurally at any site through the thickness of
the heart wall. Those of skill in the art can decide whether
epicardial, subendocardial, or some transmural location stimulation
of the muscle is best for the patient in question.
[0138] While various embodiments of systems and methods for closing
a hole in cardiac tissue have been described in considerable detail
herein, the embodiments are merely offered by way of non-limiting
examples of the disclosure described herein. It will therefore be
understood that various changes and modifications may be made, and
equivalents may be substituted for elements thereof, without
departing from the scope of the disclosure. Indeed, this disclosure
is not intended to be exhaustive or to limit the scope of the
disclosure.
[0139] Further, in describing representative embodiments, the
disclosure may have presented a method and/or process as a
particular sequence of steps. However, to the extent that the
method or process does not rely on the particular order of steps
set forth herein, the method or process should not be limited to
the particular sequence of steps described. Other sequences of
steps may be possible. Therefore, the particular order of the steps
disclosed herein should not be construed as limitations of the
present disclosure. In addition, disclosure directed to a method
and/or process should not be limited to the performance of their
steps in the order written. Such sequences may be varied and still
remain within the scope of the present disclosure,
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