U.S. patent application number 14/791995 was filed with the patent office on 2016-01-07 for telescoping catheter delivery system for left heart endocardial device placement.
The applicant listed for this patent is Medtronic, Inc.. Invention is credited to Andrea J. Asleson, Laurie D. Foerster, Michael W. Kimmel, Kyle R. Marquard, Zhongping Yang.
Application Number | 20160000563 14/791995 |
Document ID | / |
Family ID | 44913440 |
Filed Date | 2016-01-07 |
United States Patent
Application |
20160000563 |
Kind Code |
A1 |
Asleson; Andrea J. ; et
al. |
January 7, 2016 |
TELESCOPING CATHETER DELIVERY SYSTEM FOR LEFT HEART ENDOCARDIAL
DEVICE PLACEMENT
Abstract
A transseptal catheter delivery system includes an elongate
first tubular member and an elongate second tubular member
receivable within the first tubular member. The first tubular
member includes an adjustable portion adjacent a distal end. The
second tubular member is adapted to receive an instrument to be
placed in the left ventricle, and includes a curved portion
adjacent its distal end in a relaxed state. The adjustable portion
is deflectable toward the atrial septum to guide a puncturing tool
and/or guide insertion of the second tubular member through a
septal puncture into the left atrium. Within the left atrium, the
curved portion is oriented toward the left ventricle to guide
insertion of a guide wire, and subsequently the second tubular
member, into the left ventricle. Methods of transvenously accessing
a left ventricle are also provided.
Inventors: |
Asleson; Andrea J.; (Maple
Grove, MN) ; Yang; Zhongping; (Woodbury, MN) ;
Kimmel; Michael W.; (Edina, MN) ; Marquard; Kyle
R.; (Lino Lakes, MN) ; Foerster; Laurie D.;
(Mound, MN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Medtronic, Inc. |
Minneapolis |
MN |
US |
|
|
Family ID: |
44913440 |
Appl. No.: |
14/791995 |
Filed: |
July 6, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12916345 |
Oct 29, 2010 |
9072872 |
|
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14791995 |
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Current U.S.
Class: |
623/2.11 |
Current CPC
Class: |
A61M 2025/0681 20130101;
A61M 25/0662 20130101; A61B 17/00234 20130101; A61M 25/09 20130101;
A61M 25/0133 20130101; A61N 1/056 20130101; A61F 2/2427 20130101;
A61M 2025/0175 20130101; A61B 18/1492 20130101; A61B 2018/00351
20130101; A61B 2017/00247 20130101; A61M 2210/125 20130101; A61M
25/0041 20130101; A61B 2018/00601 20130101; A61B 2017/00331
20130101; A61M 29/00 20130101; A61B 17/3468 20130101; A61B 2018/144
20130101 |
International
Class: |
A61F 2/24 20060101
A61F002/24; A61N 1/05 20060101 A61N001/05 |
Claims
1. A transseptal delivery system for a heart, comprising: an
elongate first tubular member defining a first lumen extending
between a proximal end and a distal end of the first tubular
member, the first tubular member having an adjustable portion
adjacent its distal end; and an elongate second tubular member
receivable within the first tubular member, the second tubular
member defining a lumen extending between a proximal end and a
distal end of the second tubular member, the lumen adapted to
receive a puncturing tool and an instrument to be placed in the
heart, the second tubular member having a curved portion adjacent
its distal end in a relaxed state; wherein, with the first tubular
member extending through a superior entry point into a right atrium
of the heart, the adjustable portion of the first tubular member is
deflectable toward an atrial septum of the heart thereby providing
an outlet at its distal end to i) guide the puncturing tool toward
the atrial septum for creating a septal puncture, and ii) guide
insertion of the second tubular member through the septal puncture
into a left atrium of the heart; wherein, with the first tubular
member remaining in the right atrium and with the second tubular
member extending through the septal puncture into the left atrium,
the curved portion of the second tubular member is oriented toward
a left ventricle of the heart thereby providing an outlet at its
distal end to guide insertion of a guide extending through the
first and the second tubular members into the left ventricle;
wherein, with the first tubular member remaining in the right
atrium, the outlet of the first tubular member supports advancement
of the second tubular member along the guide into the left
ventricle; and wherein, with the first tubular member remaining in
the right atrium and the second tubular member extending into the
left ventricle, the lumen of the second tubular member provides a
passage for advancing the instrument into the left ventricle.
2. The delivery system of claim 1, wherein the second tubular
member is rotatable within the first tubular member through an
angular range of motion.
3. The delivery system of claim 2, wherein the angular range of
motion is at least about 360 degrees.
4. The delivery system of claim 1, further comprising a dilator
receivable within the second tubular member for facilitating
advancement of the second tubular member through the septal
puncture.
5. The delivery system of claim 1, further comprising the
puncturing tool receivable within the second tubular member for
creating the septal puncture.
6. The delivery system of claim 5, wherein the puncturing tool is
an RF puncture tool or a mechanical puncture tool.
7. The delivery system of claim 1, wherein the instrument is an
electrical lead.
8. The delivery system of claim 1, wherein in a deflected state the
first tubular member includes an elongated generally straight
portion connected to the adjustable portion, the adjustable portion
in the deflected state comprising a curved portion having a first
curved segment connected to the generally straight portion, a
second curved segment connected to the first curved segment and a
third curved segment connected to the second curved segment, each
curved segment having a different radius of curvature.
9. The delivery system of claim 8, wherein the first curved segment
has a radius of curvature between about 3 and about 4 times greater
than the radii of curvature of the second and the third curved
segments.
10. The delivery system of claim 8, wherein the third curved
segment has a subtended angle between about 3 and about 7 times
greater than subtended angles of the first and the second curved
segments.
11. The delivery system of claim 8, wherein the first and the
second curved segments have subtended angles between about 10
degrees and about 20 degrees and the third curved segment has a
subtended angle between about 60 degrees and about 90 degrees.
12. The delivery system of claim 8, wherein the first curved
segment has a subtended angle of between about 12 degrees and about
13 degrees, the second curved segment has a subtended angle of
between about 14 degrees and 16 degrees, and the third curved
segment has a subtended angle between about 70 degrees and about 80
degrees.
13. The delivery system of claim 1, wherein the adjustable portion
of the first tubular member has a deflection angle of at least
about 135 degrees with respect to a line extending from the
generally straight portion.
14. The delivery system of claim 1, wherein the adjustable portion
of the first tubular member is adjustable through a two-dimensional
range of deflection.
15. The delivery system of claim 1, wherein the adjustable portion
of the first tubular member is adjustable through a
three-dimensional range of deflection.
16. The delivery system of claim 1, wherein the adjustable portion
comprises a curved portion in a relaxed state.
17. The delivery system of claim 16, wherein the curved portion
comprises an out-of-plane configuration.
18. The delivery system of claim 1, wherein in a relaxed state the
curved portion of the second tubular member has a first curved
segment connected to a generally straight portion of the tubular
member, a second curved segment connected to the first curved
segment and a third curved segment connected to the second curved
segment, each curved segment having a different radius of
curvature, wherein the radius of curvature of the first curved
segment is between about 7 inches and about 9 inches, the radius of
curvature of the second curved segment is between about 2 inches
and about 3 inches, and the radius of curvature of the third curved
segment is between about 1 inch and about 2 inches.
19. A transseptal lead delivery system for a heart, comprising: an
elongate first tubular member defining a first lumen extending
between a proximal end and a distal end of the first tubular
member, the first tubular member having an adjustable portion
adjacent its distal end; and an elongate second tubular member
receivable within the first tubular member, the second tubular
member defining a lumen extending between a proximal end and a
distal end of the second tubular member, the lumen adapted to
receive a lead, the second tubular member having a curved portion
adjacent its distal end; wherein, with the first tubular member
extending into a right atrium of the heart, the adjustable portion
of the first tubular member is deflectable toward an atrial septum
of the heart thereby providing an outlet at its distal end to guide
insertion of the second tubular member through a septal puncture
into a left atrium of the heart; wherein, with the first tubular
member remaining in the right atrium and the second tubular member
extending through the septal puncture into the left atrium, the
curved portion of the second tubular member is directed toward a
left ventricle of the heart thereby providing an outlet at its
distal end to guide insertion of a guide extending through the
first and the second tubular members into the left ventricle;
wherein, with the first tubular member remaining in the right
atrium, the outlet of the first tubular member supports advancement
of the second tubular member along the guide into the left
ventricle; and wherein, with the first tubular member remaining in
the right atrium and the second tubular member extending into the
left ventricle, the second tubular member is rotatable within the
first tubular member and the lumen of the second tubular member
provides a rotatable passage for placement of the lead at a
plurality of sites on an endocardial wall of the left
ventricle.
20. The delivery system of claim 19, wherein the lumen of the
second tubular member is further adapted to receive a puncturing
tool and wherein, with the adjustable portion of the first tubular
member deflected toward the atrial septum, the outlet at the distal
end of the first tubular member guides the puncturing tool toward
the atrial septum for creating the septal puncture.
21. The delivery system of claim 19, the second tubular member is
rotatable through an angular range of motion with respect to the
first tubular member of at least about 360 degrees.
22-25. (canceled)
Description
RELATED APPLICATION
[0001] This application is a divisional of U.S. patent application
Ser. No. 12/916,345, filed Oct. 29, 2010 entitled "TELESCOPING
CATHETER DELIVERY SYSTEM FOR LEFT HEART ENDOCARDIAL DEVICE
PLACEMENT", herein incorporated by reference in its entirety.
FIELD
[0002] Embodiments of the present invention generally relate to
systems for delivering medical devices to the heart, and more
particularly relate to catheter based delivery systems for left
heart device placement.
BACKGROUND
[0003] In some cases it can be desirable to deliver and position a
medical device in or near the left side of a patient's heart for
diagnosing and/or treating cardiovascular disease. As just one
example, patients with heart failure can in some cases be treated
with cardiac resynchronization therapy (CRT) delivered with a
collection of electrical leads, one of which is placed proximate
the left ventricle for bi-ventricular pacing. A traditional
placement for a left ventricular (LV) lead is a transvenous
placement into one of the tributaries of the coronary sinus (CS).
By some estimates, however, up to 40-50% of CRT patients do not
respond to CRT with a traditional CS lead placement. One
alternative to a traditional CS lead placement is a left
ventricular endocardial lead placement. An LV endocardial placement
may be useful for patients with poor CS lead access or stability or
those with failed CS implants. Accordingly, there is a growing
interest in LV endocardial lead placement.
[0004] Delivery catheters are often used to position electrical
leads (and other medical devices) at various cardiovascular sites
(e.g., such as a LV endocardical placement) within a patient via
minimally invasive techniques. These catheters are constructed
having a lumen, which provides a pathway to the implant site,
through which an implanting physician may pass the medical device
without encountering anatomical obstructions. Some delivery
catheters include mechanisms, such as pull-wire actuation, which
allow the implanting physician to actively change a curvature of
the catheter in order to direct a distal tip of the catheter to a
target implant site. Such catheters may be referred to as being
"steerable" or "deflectable." Other delivery catheters have
resilient, pre-formed curvatures tailored to position a distal tip
thereof at a particular anatomical site from a particular
percutaneous access site. Such "fixed-shape" catheters can thus
eliminate or reduce the need to actively control the curvature
during the implant procedure.
[0005] In some cases delivery systems may include combinations of
two or more steerable and/or fixed shape catheters. U.S. Patent
Application Publication 2003/0144657 discloses one example of a
catheter assembly employing an outer catheter with a pre-formed
distal end and an inner catheter with a pre-formed distal end.
Relative rotation and extension of the inner and outer catheters
provides adjustable shaping of the catheter assembly's distal tip
for improved locating and cannulating of, e.g., the coronary sinus
via the right atrium. Another example of a coronary sinus access
system is the ATTAIN SELECT.RTM. II 6248DEL delivery catheter
system available from Medtronic, Inc., which can be used with an
outer catheter such as the ATTAIN.RTM. 6227DEF deflectable catheter
delivery system, also available from Medtronic, Inc.
[0006] Another common approach for accessing the left side of the
heart is a transseptal access from the right atrium through the
intra-atrial septum to the left atrium. U.S. Pat. No. 7,678,081,
and U.S. Patent Application Publication 2007/0083168 provide
examples of catheter systems employing a right to left atrial
transseptal approach. U.S. Pat. No. 7,678,081 discloses, among
other things, a catheter system including a guiding catheter, an
access catheter, and a guide wire, which may be introduced to the
right atrium from an inferior or a superior route. The catheter
system includes a tissue penetration member carried by the access
catheter for penetrating the septal wall. U.S. Patent Application
Publication 2007/0083168 discloses another catheter system that
accesses the left atrium from the right atrium by penetrating the
intra-atrial septal wall. Among other things, the publication
discloses a system including a stabilizer sheath having a side
port, a shaped guiding catheter configured to exit the side port,
and a tissue penetration member disposed within the guide
catheter.
[0007] Methods of transvenously accessing the left ventricle are
also known in the art. For example, a left heart catheterization
can provide access to the left ventricle in a retrograde direction
across the aortic valve, or a transseptal cardiac catheterization
can access the left ventricle from the right atrium through the
intra-atrial septum and left atrium. U.S. Pat. No. 6,156,018
discloses at least one example of the latter approach using a right
femoral vein/inferior vena cava access. Another transseptal
approach to the left ventricle includes the use of a Medtronic
ATTAIN.RTM. 6227DEF deflectable catheter delivery system with a
right Judkins catheter. Berry M. van Gelder, PhD, et al.
Transseptal endocardial left ventricular pacing: An alternative
technique for coronary sinus lead placement in cardiac
resynchronization therapy. Heart Rhythm, Vol 4, No 4, April 2007,
454-460.
[0008] While a large number of catheter systems and delivery
methods are presently available for accessing the heart, there
remains a need for improved systems, especially for accessing the
left ventricle of the heart.
SUMMARY
[0009] Embodiments of the invention generally provide transseptal
delivery systems and methods for accessing a left ventricle of a
heart. According to one aspect of the invention, a transseptal
delivery system for a heart includes an elongate first tubular
member and an elongate second tubular member. The first tubular
member defines a first lumen extending between a proximal end and a
distal end of the first tubular member, and has an adjustable
portion adjacent its distal end. The second tubular member is
receivable within the first tubular member and defines a lumen
extending between a proximal end and a distal end of the second
tubular member. The lumen of the second tubular member is adapted
to receive a puncturing tool and an instrument to be placed in the
heart. The second tubular member also has a curved portion adjacent
its distal end in a relaxed state.
[0010] When deployed with the first tubular member extending
through a superior entry point into a right atrium of the heart,
the adjustable portion of the first tubular member is deflectable
toward an atrial septum of the heart thereby providing an outlet at
its distal end to i) guide the puncturing tool toward the atrial
septum for creating a septal puncture, and ii) guide insertion of
the second tubular member through the septal puncture into a left
atrium of the heart. After extending the second tubular member
through the septal puncture into the left atrium while maintaining
the first tubular member in the right atrium, the curved portion of
the second tubular member is oriented toward a left ventricle of
the heart. An outlet at its distal end can thus guide insertion of
a guide extending through the first and the second tubular members
into the left ventricle. Thereafter, the outlet of the first
tubular member, while remaining in the right atrium, supports
advancement of the second tubular member along the guide into the
left ventricle. With the first tubular member remaining in the
right atrium and the second tubular member extending into the left
ventricle, the lumen of the second tubular member provides a
passage for advancing the instrument into the left ventricle.
[0011] According to another aspect of the invention, a transseptal
delivery system for a heart includes an elongate first tubular
member defining a first lumen extending between a proximal end and
a distal end of the first tubular member. The system also includes
an elongate second tubular member receivable within the first
tubular member. The second tubular member defines a lumen extending
between a proximal end and a distal end of the second tubular
member adapted to receive a lead. The first tubular member includes
an adjustable portion adjacent its distal end and the second
tubular member includes a curved portion adjacent its distal end.
When the first tubular member is extending into a right atrium of
the heart, the adjustable portion of the first tubular member is
deflectable toward an atrial septum of the heart thereby providing
an outlet at its distal end to guide insertion of the second
tubular member through a septal puncture into a left atrium of the
heart. Thereafter, with the first tubular member remaining in the
right atrium and the second tubular member extending through the
septal puncture into the left atrium, the curved portion of the
second tubular member is directed toward a left ventricle of the
heart. The second tubular member includes an outlet at its distal
end that guides insertion of a guide extending through the first
and the second tubular members into the left ventricle. With the
first tubular member remaining in the right atrium, the outlet of
the first tubular member supports advancement of the second tubular
member along the guide into the left ventricle. The second tubular
member is rotatable within the first tubular member and the lumen
of the second tubular member provides a rotatable passage for
placement of the lead at a plurality of sites on an endocardial
wall of the left ventricle.
[0012] According to another aspect of the invention, a transseptal
delivery system includes a lead delivery catheter that is
telescopically received within a deflectable catheter. The
deflectable catheter includes a deflectable portion adjacent its
distal end that is adapted to approach the intra-atrial septum of a
heart when advanced through the superior vena cava into the right
atrium of the heart. The lead delivery catheter includes a
resilient curved portion adjacent its distal end that is adapted to
direct the delivery system into the left ventricle after having
been advanced through the atrial septum into the left atrium.
[0013] According to another aspect of the invention, a transseptal
delivery system or kit includes a deflectable catheter, a lead
delivery catheter, a dilator, and a septal puncturing tool and/or a
guide wire. When assembled and initially deployed, the components
are coaxially positioned in order from the innermost member: guide
wire and/or septal puncturing tool, dilator, lead delivery
catheter, and deflectable catheter. After accessing the left
ventricle and withdrawing the guide wire/puncturing tool and
dilator, the coaxial deflectable catheter and lead delivery
catheter provide a lead delivery passage from the patient exterior
to the atrial septum and the lead delivery catheter alone provides
a lead delivery passage from the atrial septum to the left
ventricle.
[0014] According to another aspect of the invention, a method for
transseptal delivery in a heart is provided. The method includes
advancing an elongate first tubular member through a superior vena
cava into a right atrium of the heart. The first tubular member
defines a first lumen extending between a proximal end and a distal
end of the first tubular member. The first tubular member also has
an adjustable portion adjacent its distal end. The method further
includes deflecting the adjustable portion of the first tubular
member within the right atrium toward an atrial septum of the heart
and advancing a stiffening member through the first tubular member
and through a septal puncture in the atrial septum into a left
atrium of the heart. The method also includes advancing an elongate
second tubular member through the first tubular member and through
the septal puncture into the left atrium over the stiffening member
while maintaining the first tubular member within the right atrium.
The second tubular member defines a lumen extending between a
proximal end and a distal end of the second tubular member. The
lumen receives the stiffening member. The second tubular member has
a normally curved portion adjacent its distal end that straightens
when advanced through the first tubular member and over the
stiffening member. The method further includes withdrawing the
stiffening member from at least a portion of the second tubular
member, thereby allowing the curved portion of the second tubular
member to regain its normally curved shape, thereby directing an
outlet at the distal end of the second tubular member toward a left
ventricle of the heart. The method also includes advancing a guide
through the second tubular member into the left ventricle,
advancing the second tubular member over the guide into the left
ventricle while maintaining the first tubular member within the
right atrium, and advancing an instrument through the second
tubular member into the left ventricle.
[0015] Embodiments of the present invention can optionally provide
one or more of the following features and/or advantages. In some
cases the second tubular member is rotatable within the first
tubular member to facilitate lead placement at a variety of
locations within the left ventricle. The second tubular member is
rotatable through an angular range of motion, which in some cases
is at least about 360 degrees. A system or kit at a minimum
preferably, though not necessarily, provides the first and the
second tubular members. In some cases, though, a system or kit may
optionally also include a dilator receivable within the second
tubular member for facilitating advancement of the second tubular
member through the septal puncture. The system/kit may also
optionally include a puncturing tool, such as an RF wire or a
transseptal needle that can be advanced through the second tubular
member for puncturing the septal wall. In some cases the system/kit
may also include other components.
[0016] While it is contemplated that embodiments will be useful for
placing electrical leads within the left ventricle, a number of
other advantageous uses are available with exemplary catheter
systems. For example, exemplary systems may be used for delivering
other therapies to the left side of the heart, including leaded or
leadless sensors, leadless pacers, and other items.
[0017] In addition, some exemplary catheter systems advantageously
provide a single, integrated system for transvenously accessing the
left heart from a superior access point. For example, a surgeon can
insert the entire delivery system into a patient's vasculature from
a superior location, such as the left or right subclavian vein. In
one embodiment an RF transseptal wire also acts as a guide wire and
is inserted through the patient's vasculature into the right
atrium. A deflectable catheter can then be tracked over the guide
wire into the right atrium and deflected back toward the atrial
septum to align the transseptal guide wire with a preferred
puncture point in the atrial septum (e.g., the fossa ovalis). After
puncturing the atrial septum, the guide wire, a dilator, and a lead
delivery catheter can be tracked into the left atrium, redirected
toward the mitral valve, and advanced into the left ventricle, thus
providing a lead delivery passage upon withdrawing the dilator and
guide wire. Accordingly, some embodiments of the invention can
avoid the use of multiple access points and multiple transvenous
passages, thus limiting trauma and speeding recovery time for the
patient.
[0018] These and various other features and advantages will be
apparent from a reading of the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The following drawings are illustrative of particular
embodiments of the present invention and therefore do not limit the
scope of the invention. The drawings are not to scale (unless so
stated) and are intended for use in conjunction with the
explanations in the following detailed description. Embodiments of
the present invention will hereinafter be described in conjunction
with the appended drawings, wherein like numerals denote like
elements.
[0020] FIG. 1 is a partial side view of a catheter delivery system
in accordance with an embodiment of the invention.
[0021] FIG. 2A is a side cross-sectional view of a deflectable
catheter in accordance with an embodiment of the invention.
[0022] FIGS. 2B and 2C are partial cross-sectional views of the
deflectable catheter of FIG. 2A.
[0023] FIG. 3A is a side cross-sectional view of a lead delivery
catheter in accordance with an embodiment of the invention.
[0024] FIG. 3B is a partial cross-sectional view of the lead
delivery catheter of FIG. 3A.
[0025] FIG. 4A is a side cross-sectional view of a lead delivery
catheter in accordance with an embodiment of the invention.
[0026] FIG. 4B is a partial cross-sectional view of the lead
delivery catheter of FIG. 4A.
[0027] FIGS. 5A-5F are cross-sectional views illustrating a
sequence of steps for accessing a left ventricle in accordance with
an embodiment of the invention.
[0028] FIGS. 6A-6B are perspective views of a curved portion of a
lead delivery catheter within a left atrium in accordance with an
embodiment of the invention.
[0029] FIG. 7 is a perspective view of a guide wire and lead
delivery catheter advanced through a mitral valve into a left
ventricle in accordance with an embodiment of the invention.
[0030] FIGS. 8A-8C are perspective views illustrating multiple
rotational positions of a lead delivery catheter within a left
ventricle in accordance with an embodiment of the invention.
[0031] FIG. 9 is a perspective view illustrating placement of an
electrical lead within a left ventricle in accordance with an
embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] The following detailed description is exemplary in nature
and is not intended to limit the scope, applicability, or
configuration of the invention in any way. Rather, the following
description provides some practical illustrations for implementing
exemplary embodiments of the present invention. Examples of
constructions, materials, dimensions, and manufacturing processes
are provided for selected elements, and all other elements employ
that which is known to those of ordinary skill in the field of the
invention. Those skilled in the art will recognize that many of the
noted examples have a variety of suitable alternatives.
[0033] FIG. 1 is a partial perspective view of a catheter delivery
system 100 in accordance with an embodiment of the invention. Among
other things, the delivery system 100 includes an outer deflectable
catheter 102, an inner delivery catheter 104, a dilator 106, and a
transseptal puncturing tool 108 in the from of a radio frequency
(RF) transseptal wire. Each of the outer deflectable catheter 102,
inner delivery catheter 104 and dilator 106 includes an inner
lumen, and as shown in FIG. 1, the components are received together
in a telescoping fashion with the puncturing tool 108 at the center
of the nested components. The delivery system 100 thus provides a
multi-functional system that integrates a steerable, configurable
delivery catheter system with transseptal puncturing capability.
Accordingly, the delivery system 100 provides a one-stop solution
for steering through vasculature to a septal wall, puncturing the
wall, and delivering a payload through the septal puncture, all
from a single entry point.
[0034] Returning to FIG. 1, the delivery system 100 also includes
valves 110 and associated side ports 112 positioned between the
components for limiting blood outflow while also providing access
to the inner lumens of the components. Also, although not shown in
FIG. 1, the catheter delivery system 100 may optionally be provided
with a percutaneous needle and a syringe for inserting the delivery
system 100 into a patient. The system may also include a catheter
slitter, a guide wire tip straightener, and/or any other desirable
components known in the art. In some cases a typical guide wire may
be used in place of or in addition to the RF wire 108 to advance
the delivery system 100 through the patient's vasculature. As just
one example, the delivery system 100 may be routed through a
preexisting septal puncture e.g., made by another device or
naturally occurring (e.g., patent foramen ovale).
[0035] The transseptal puncturing tool 108 can be provided in any
suitable form, and in some cases may comprise a transvenous needle
for mechanical puncturing or an RF wire as illustrated. For
example, in one embodiment the puncturing tool 108 is an RF
Transseptal Wire available from Baylis Medical. Preferably, the RF
transseptal wire (or optionally standard guide wire) includes a
small curve or "pig tail" on its distal end to avoid unwanted
perforation of other structures once through the septum when coming
from a superior approach. Similarly, the dilator 106 can be
provided in a number of formats and in one case is a Baylis Medical
Transseptal Dilator. Preferably the dilator 106 provides a
continuous, smooth transition between the puncturing tool/guide
wire and the delivery catheter 104 in order to avoid undesired
tearing or other tissue damage as the larger diameter delivery
catheter 104 is advanced through the septal puncture.
[0036] In some cases two or more components of the delivery system
100 may be packaged and sold together as a kit. For example, one
kit can include all of the components just described above. In some
embodiments, a delivery system and/or kit at a minimum includes the
deflectable catheter 102 and the delivery catheter 104 as they
provide complementary functionality that when combined provides a
more flexible and configurable delivery system. For example, in
some cases the delivery and deflectable catheters are adapted to
cooperatively provide a delivery passage to the left ventricle of a
human's heart. In some embodiments the deflectable and delivery
catheters 102, 104 are advantageously adapted to access the left
heart from a superior access point (e.g., a subclavian access
point) and a transseptal approach across the intra-atrial septum.
In some cases curves on the lead delivery catheter 104 are designed
to help direct the system 100 through the mitral valve and also
create sufficient access to multiple sites on the left ventricular
endocardium. The delivery system 100 is thus extremely useful for
delivering medical instruments such as leads, leaded or leadless
sensors and/or pacers, catheters, guide wires, and other
instruments to the left heart while minimizing patient trauma
normally associated with multiple entry points and multiple
transvenous pathways.
[0037] FIG. 2A is a side cross-sectional view of the deflectable
catheter 102 in accordance with an embodiment of the invention. In
general, the deflectable catheter 102 includes an elongate tubular
member 200 that defines a lumen extending between a proximal end
202 and a distal end 204 of the tubular member 200. The lumen is
adapted to telescopically receive the lead delivery catheter 104
shown in FIG. 1. The tubular member also has a generally straight
portion 205 and an adjustable portion 206 adjacent to the distal
end 204 of the member. The catheter 102 includes a hub 208 at the
proximal end of the tubular member and an adjustable catheter
handle 210 that can be manipulated, e.g., rotated, to deflect the
adjustable portion 206 of the catheter. The catheter 102 can be
manufactured from any suitable biocompatible material. In some
cases it is made from polyether block amide.
[0038] The adjustable portion 206 can be provided with one of a
variety of curved configurations in its relaxed and/or deflected
state. As shown in FIG. 2A, in an initial relaxed state R, the
adjustable portion 206 is a substantially straight continuation of
the generally straight portion 205. The adjustable portion 206 can
then be moved through a range of deflection 209 by turning the
handle 210. In an alternative embodiment, the adjustable portion
206 may be provided with a resilient, flexible curve in its initial
relaxed state that can also be deflected. Turning to FIG. 2C, in
some cases the adjustable portion 206 may deflect back toward the
catheter hub by an angle 207 of at least 135 degrees. The
deflection can be used to align the outlet at the distal end 204 of
the tubular member to i) guide a puncturing tool toward the atrial
septum for creating a septal puncture, and/or ii) guide insertion
of a second tubular member (i.e., delivery catheter 104) through
the septal puncture into a left atrium of the heart. Thus, a single
deflectable outer catheter can be designed, manufactured, and used
without the need for multiple outer catheters of varying
shapes.
[0039] Although not shown in the figures, according to some
embodiments the adjustable portion 206 (and optionally part of the
straight portion 205) is provided with an out-of-plane or
three-dimensional configuration. Referring to FIG. 2A, the handle
210 and the straight portion 205 of the tubular member can define a
reference plane. While is some cases the adjustable portion 206
remains within the reference plane (thus providing a
two-dimensional range of deflection), in at least one configuration
the distal end 204 of the adjustable portion 206 extends in to or
out from the reference plane. For example, the adjustable portion
206 may be preformed with a resilient curve such that the distal
end 204 extends transversely out from or in to the reference plane
by an amount ranging from 0-90 degrees. In some cases the
out-of-plane angle may range between 45-90 degrees. Thus, as the
adjustable portion 206 is swept through the range of deflection,
the distal end of the catheter moves outside the reference
plane.
[0040] In another configuration, the adjustable portion 206 is
within the reference plane in a relaxed state, but can be deflected
back toward the handle 210 along a three-dimensional path within
the reference plane or out from the reference plane. In this case
the range of deflection is not solely a planar range, but can
include a volumetric or three-dimensional range such as a portion
of a sphere. In some cases the range of deflection may extend out
from the reference plane between 0-90 degrees or between 45-90
degrees in either direction. Thus, the adjustable or deflectable
portion 206 of the catheter 102 advantageously lets the catheter
accommodate or compensate for variations in anatomy across classes
of patients.
[0041] FIG. 2B is a partial cross-sectional view illustrating the
adjustable portion 206 of the deflectable catheter 102 in one
possible deflection state. In some embodiments the deflectable
catheter 102 is adapted for being inserted into the right atrium
through the superior vena cava and then deflected to approach the
intra-atrial septum. In one case the catheter 102 is provided with
an inner diameter to accommodate passage of multiple catheters
and/or instruments therethrough, while also being equipped with a
curved section dimensioned to accommodate the typical anatomy of
the superior vasculature, the right atria, and the intra-atrial
septum. For example, according to some embodiments the first
tubular member 200 has an inner diameter between about 0.08-0.12
inches, between about 0.9-0.11 inches, or of about 0.1 inch. In
some embodiments, the adjustable portion 206 of the catheter 102
may have a reach 210 of between about 2-3 inches, between about
2.1-2.8 inches, or about 2.4 inches in a deflected state. In some
cases the adjustable portion 206 of the deflectable catheter 102
has a longitudinal length 212 of between about 0-4 inches, between
about 1-3 inches, or of about 2 inches or about 2.12 inches in one
preferred deflection state.
[0042] Continuing with reference to FIG. 2B, in one preferred
deflection state, the first tubular member's adjustable portion 206
includes a short, straight portion 220 (e.g., about 0.85 inches
long in some cases) adjacent the distal end 204 and a curved
portion 222 connected between the straight portion 220 and the
generally straight portion 205. In some cases the curved portion
222 comprises multiple curved segments forming a compound curve.
Referring to FIG. 2B, in some cases the curved portion 222 has a
first curved segment 230 connected to the generally straight
portion 205, a second curved segment 232 connected to the first
curved segment 230 and a third curved segment 234 connected to the
second curved segment 232.
[0043] According to an embodiment of the invention, each of the
multiple curved segments has a different radius of curvature
designed to adapt the adjustable portion 206 for use within the
right atrium. For example, in some cases the first curved segment
230 has a radius of curvature 240 between about 3 and about 4 times
greater than the radii of curvature 242, 244 of the second and the
third curved segments, respectively. In a specific example, the
radius of curvature 240 of the first curved segment is about 4.86
inches, the radius of curvature 242 of the second curved segment is
about 1.36 inches, and the radius of curvature 244 of the third
curved segment is about 1.17 inches.
[0044] According to another embodiment of the invention, each of
the multiple curved segments has a different subtended angle
designed to adapt the adjustable portion 206 for use within the
right atrium. For example, in some cases the third curved segment
234 has a subtended angle 254 between about 3 and about 7 times
greater than the subtended angles 250, 252 of the first and the
second curved segments, respectively. In one embodiment the first
subtended angle 250 and the second subtended angle 252 are each
between about 10 degrees and about 20 degrees, while the third
subtended angle 254 is between about 60 degrees and about 90
degrees. In another embodiment the first subtended angle 250 is
between about 12 and 13 degrees, the second subtended angle 252 is
between about 14 and about 16 degrees, and the third subtended
angle 254 is between about 70 and 80 degrees. Still more
specifically, in one embodiment the first subtended angle 250 is
about 12.7 degrees, the second subtended angle 252 is about 15
degrees, and the third subtended angle 254 is about 74.2
degrees.
[0045] Of course these are just a few examples of particular
designs for one deflection state of a deflectable catheter
according to embodiments of the invention. Other possible designs
for an outer catheter not shown here include an out-of-plane design
(as opposed to the two-dimensional design illustrated in the
figures), the use of a fixed-shape catheter instead of an
adjustable catheter, and/or a catheter designed for intra-atrial
access from the inferior vena cava. In the case of the latter, the
curved portion of the catheter would have a generally more open
angle to accommodate the particular anatomy encountered when
advancing through the inferior vena cava.
[0046] FIG. 3A is a side cross-sectional view of a lead delivery
catheter 300 in accordance with an embodiment of the invention. The
lead delivery catheter 300 generally includes an elongated second
tubular member 301 defining a lumen extending between a proximal
end 302 and a distal end 304 of the second tubular member 301. A
hub 308 is coupled to the lumen at the proximal end 302 of the
tubular member 301. In some embodiments the lumen is adapted to
receive one or more of the puncturing tool 108, the dilator 106,
and/or an instrument to be placed in the heart, such as an
electrical lead. The second tubular member 301 also includes a
generally straight portion 305 and, in a relaxed state, a curved
portion 306 adjacent its distal end 304.
[0047] The curved portion 306 of the delivery catheter 300 is a
resilient, flexible curve in the catheter body, the type of which
are well known in the art. Accordingly, the curved portion 306
straightens as the delivery catheter 300 is tracked over the
dilator 106, but reverts back to its normally relaxed, curved shape
when the dilator 106 is removed. According to an embodiment of the
invention, the delivery system 100 utilizes the resiliency of the
curved portion 306 to steer the delivery system 100 without use of
the deflectable catheter. For example, in some cases the
deflectable catheter is advanced up to the intra-atrial septal
wall, but not advanced through the septal puncture. The lead
delivery catheter is tracked over the dilator 106 and a guide
wire/transseptal wire into the left atrium. To reach the left
ventricle, at this point the dilator 106 is withdrawn and the
delivery catheter resumes its normally curved shape, thus directing
the guide wire toward the mitral valve and into the left ventricle.
Once stationed within the left ventricle, the guide wire can be
used to track the delivery catheter into the left ventricle while
the deflectable catheter remains in the right atrium. After
removing the guide wire, the lead delivery catheter provides a
passage for advancing an instrument (e.g., electrical lead) into
the left ventricle.
[0048] According to some embodiments, the second tubular member's
curved portion 306 includes a short, straight portion 320 (e.g.,
about 0.498 inches long in some cases) adjacent the distal end 304
and a curved portion 322 connected between the straight portion 320
and the generally straight portion 305. In some cases the curved
portion 322 comprises multiple curved segments forming a compound
curve. Referring to FIG. 3B, in some cases the curved portion 322
has a first curved segment 330 connected to the generally straight
portion 305, a second curved segment 332 connected to the first
curved segment 330 and a third curved segment 334 connected to the
second curved segment 332.
[0049] According to an embodiment of the invention, each of the
multiple curved segments has a different radius of curvature
designed to adapt the curved portion 306 for use within the left
atrium. For example, in some cases the first curved segment 330 has
a radius of curvature 340 between about 7 inches and about 9
inches, the radius of curvature 342 of the second curved segment
332 is between about 2 inches and about 3 inches, and the radius of
curvature 344 of the third curved segment 334 is between about 1
inch and about 2 inches. In a specific example, the radius of
curvature 340 of the first curved segment is about 7.96 inches, the
radius of curvature 342 of the second curved segment is about 2.230
inches, and the radius of curvature 344 of the third curved segment
is about 0.100 inches.
[0050] In some embodiments the curved portion 306 of the catheter
300 may have a relaxed reach 310 of between about 1-3 inches,
between about 1.5-2.5 inches, or about 2.1 inches. In some cases
the curved portion 306 of the delivery catheter 300 has a
longitudinal length 312 of between about 1-5 inches, between about
2-4 inches, or of about 2.931 inches.
[0051] Upon advancing into the left ventricle, the curved portion
306 of the delivery catheter 300 can be useful for placing a lead
or other item at one of a plurality of locations upon the LV
endocardial wall. In a typical operation, the delivery catheter 300
is rotatable within the deflectable catheter through an angular
range of motion that in some cases is at least about 360 degrees.
Thus, use of the deflectable catheter as a support or workstation
for the delivery catheter to rotate in, as well as the curved
portion of the delivery catheter, allow for lead placement at a
variety of locations on the LV wall.
[0052] Referring again to FIGS. 3A and 3B, the somewhat open curve
in this example can be useful for placing a lead or other
instrument near the left ventricular apex. FIGS. 4A and 4B
illustrate another example of a delivery catheter 400 that can be
useful for placing a lead underneath the cusp of the mitral valve.
The delivery catheter 400 is similar in many respects to the
catheter shown in FIGS. 3A-3B, and thus is only briefly described.
Of particular note is that the delivery catheter 400 includes a
curved portion 406 that includes a straight portion 420 (e.g.,
about 0.394 inches long in some cases) and a curved portion 422
that comprises a single curved segment 430. In some cases the
curved segment 430 has a radius of curvature 440 of between about 0
and about 1 inch, and in some cases about 0.5 inches. In some
embodiments the curved portion 406 of the catheter 400 may have a
relaxed reach 410 of between about 0.5-1.5 inches or about 1.184
inches. In some cases the curved portion 406 of the delivery
catheter 400 has a longitudinal length 412 of about 0.590
inches.
[0053] FIGS. 5A-5F are cross-sectional views illustrating a
sequence of steps for accessing a left ventricle in accordance with
an embodiment of the invention. Referring first to FIG. 5A, in this
embodiment a catheter delivery system 500, similar to the
embodiments described herein above, is advanced into the right
atrium 552 of the heart 550 via the left subclavian vein 554 and
the superior vena cava 556. The catheter delivery system 500
generally includes an elongate first tubular member 502 including
an adjustable portion adjacent its distal end of the same character
as the deflectable catheters described above. The system 500
further includes a second tubular member 504 including a normally
curved portion 505 adjacent its distal end that straightens when
advanced through the first tubular member 502 and over a stiffening
member 506 (e.g., a dilator). The system 500 also includes a
transseptal puncturing tool 508, such as a transseptal RF wire.
[0054] Continuing with reference to FIG. 5A, the method includes
advancing the transseptal puncturing tool 508 (or alternatively a
simple guide wire) into the right atrium 552, and then tracking the
dilator 506, the second tubular member 504, and the first tubular
member 502 over the guide 508 through the superior vena cava 556
into the right atrium 552 of the heart 550. Referring to FIGS. 5B
and 5C, the method further includes deflecting an adjustable
portion 520 of the first tubular member within the right atrium 552
toward the atrial septum 560 of the heart 550. In some embodiments
the method optionally includes tenting the atrial septum 560 at or
near the fossa ovalis with the second tubular member 504 and/or the
dilator 506, and puncturing the atrial septum 560 with the
puncturing tool 508. For example, a transseptal RF wire (e.g.,
Baylis Medical RF wire) can be energized (e.g., 25 W for 2 seconds)
to form a small puncture hole in the septum. In some cases, though,
an atrial puncture may already be present (from previous puncture,
or naturally) and a separate puncture tool is not necessary.
[0055] Turning to FIG. 5D, the method includes advancing the guide
wire or puncturing tool 508 through the atrial septum 560 into the
left atrium 562. The stiffening member or dilator 506 and the
second tubular member 504 are then tracked over the guide 508 into
the left atrium 562, while maintaining the first tubular member in
the right atrium 552. At this point, the method includes
withdrawing the stiffening member 506 from at least a portion of
the second tubular member 504, thereby allowing the curved portion
505 to regain its normally curved shape. Upon regaining its curved
shape, the outlet at the distal end of the second tubular member
504 is directed toward the mitral valve 564 and the left ventricle
566 of the heart 550. In some cases slight adjustment may be
desirable, and the distal end of the second tubular member 504 can
be rotated within the first tubular member 502 to more directly
align it with the mitral valve 564. FIGS. 6A and 6B provide
perspective views of before and after withdrawing the dilator 506
to allow the second tubular member 504 to regain its resting state
curve 505
[0056] Turning to FIGS. 5E and 7, after aligning the second tubular
member with the mitral valve 564, the method includes advancing the
guide 508 through the second tubular member 504 into the left
ventricle 566. Referring to FIGS. 5E, 5F, and 7, the second tubular
member 504 is then tracked over the guide 508 into the left
ventricle 566, while the first tubular member 502 is still
maintained in the right atrium 552.
[0057] Thus, the catheter delivery system 500 can provide a passage
from exterior the patient into the left ventricle 566 for placing
an instrument, such as a lead. FIGS. 8A-8C illustrate the second
tubular member having resumed its natural curved state, thus
providing an advantageous angled distal tip for sweeping about the
left ventricle 566 as the second tubular member 504 is rotated
within the first tubular member 502. Accordingly, an instrument,
such as the lead 540 shown in FIG. 8, can be placed at any one of a
plurality of locations on the endocardial wall 570 of the left
ventricle 566.
[0058] Thus, embodiments of the invention are disclosed. Although
the present invention has been described in considerable detail
with reference to certain disclosed embodiments, the disclosed
embodiments are presented for purposes of illustration and not
limitation and other embodiments of the invention are possible. One
skilled in the art will appreciate that various changes,
adaptations, and modifications may be made without departing from
the spirit of the invention and the scope of the appended
claims.
* * * * *