U.S. patent application number 14/841749 was filed with the patent office on 2017-03-02 for stent assemblies including passages to provide blood flow to coronary arteries and methods of delivering and deploying such stent assemblies.
The applicant listed for this patent is Medtronic, Inc.. Invention is credited to Shishira Nagesh, Paul Rothstein.
Application Number | 20170056215 14/841749 |
Document ID | / |
Family ID | 56889241 |
Filed Date | 2017-03-02 |
United States Patent
Application |
20170056215 |
Kind Code |
A1 |
Nagesh; Shishira ; et
al. |
March 2, 2017 |
STENT ASSEMBLIES INCLUDING PASSAGES TO PROVIDE BLOOD FLOW TO
CORONARY ARTERIES AND METHODS OF DELIVERING AND DEPLOYING SUCH
STENT ASSEMBLIES
Abstract
An anchor stent assembly to be used with a valve component
includes a generally tubular frame having a first end and a second
end, the frame defining a central passage and a central axis. A
secondary passage is defined between n inner surface of the frame
and an outer surface of an inner rib disposed closer to the central
axis than the frame. An extension tube is disposed through the
secondary passage. The extension tube includes an extension tube
lumen having a first opening at a first end of the extension tube
and a second opening at a second end of the extension tube.
Inventors: |
Nagesh; Shishira; (San
Francisco, CA) ; Rothstein; Paul; (Elk River,
MN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Medtronic, Inc. |
Minneapolis |
MN |
US |
|
|
Family ID: |
56889241 |
Appl. No.: |
14/841749 |
Filed: |
September 1, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 2/966 20130101;
A61F 2002/91533 20130101; A61F 2250/0039 20130101; A61F 2220/0008
20130101; A61F 2002/8486 20130101; A61F 2230/0069 20130101; A61F
2002/91575 20130101; A61F 2002/826 20130101; A61F 2/915 20130101;
A61F 2230/005 20130101; A61F 2002/061 20130101; A61F 2002/91583
20130101; A61F 2002/828 20130101; A61F 2/2418 20130101; A61F 2/07
20130101; A61F 2/856 20130101; A61F 2250/006 20130101; A61F 2/2436
20130101 |
International
Class: |
A61F 2/856 20060101
A61F002/856 |
Claims
1. A stent assembly having a radially compressed delivery
configuration and a radially expanded deployed configuration, the
stent assembly comprising: a generally tubular frame having a first
end and a second end, the frame defining a central passage and a
central axis; a secondary passage, defined between an inner surface
of the frame and an outer surface of an inner rib closer to the
central axis than the frame; and an extension tube extending
through the secondary passage, the extension tube including an
extension tube lumen having a first opening at a first end of the
extension tube and a second opening at a second end of the
extension tube.
2. The stent assembly of claim 1, wherein the stent assembly is
configured to be deployed within an aorta adjacent to the aortic
sinuses.
3. The stent assembly of claim 2, wherein the secondary passage is
aligned parallel with the central axis of the frame.
4. The stent assembly of claim 2, wherein the secondary passage
comprises two passages, and the extension tube comprises two
extension tubes, with each extension tube extending through a
corresponding one of the secondary passages.
5. The stent assembly of claim 2, wherein the extension tube is
configured such that the extension tube aligns circumferentially
with, but does not obstruct, an ostium of a coronary artery.
6. The stent assembly of claim 2, wherein the extension tube is
configured to receive a coronary stent.
7. The stent assembly of claim 6, wherein the extension tube is
configured such that a first portion of the coronary stent is
disposed within the extension tube and a second portion of the
coronary stent extends into the coronary artery.
8. The stent assembly of claim 6, wherein when the stent assembly
and the coronary stent are in their second, radially expanded
deployed configuration, the extension tube is in fluid
communication with the coronary stent and the coronary stent is in
fluid communication with the coronary artery.
9. A method of implanting a stent assembly at a location in an
aorta comprising the steps of: advancing the stent assembly in a
radially compressed delivery configuration to the location in the
aorta, wherein the stent assembly comprises a generally tubular
frame having a first end and a second end, a central passage, a
central axis, a secondary passage formed between an inner surface
of the frame and an outer surface of an inner rib closer to the
central axis than the frame, and an extension tube extending
through the secondary passage, the extension tube being coupled to
the frame and having an extension tube lumen; rotationally
orienting the stent assembly such that the extension tube generally
circumferentially aligned with an ostium of a coronary artery;
deploying the stent assembly from the radially compressed delivery
configuration to a radially expanded deployed configuration at the
location within the aorta; advancing a coronary stent in a radially
compressed delivery configuration through the extension tube lumen
such that a first portion of the coronary stent resides within the
extension tube lumen and a second portion of the coronary stent
extends into the coronary artery; and deploying the coronary stent
assembly from the radially compressed delivery configuration to a
radially expanded deployed configuration.
10. The method of claim 9, further comprising the steps of:
delivering a valve component in a radially compressed delivery
configuration to a location within a native aortic valve; and
deploying the valve component such that the valve component expands
from the radially compressed delivery configuration to a radially
expanded configuration.
11. The method of claim 9, wherein the secondary passage of the
stent assembly comprises two secondary passages and the extension
tube comprises two extensions tubes disposed within a respective
one of the two secondary passages, wherein the step of rotationally
orienting the stent assembly comprises circumferentially aligning
one of the extension tubes with the ostium of the left coronary
artery and circumferentially aligning the other of the two
extension tubes with the right coronary artery.
12. A stent assembly having a radially compressed delivery
configuration and a radially expanded deployed configuration, the
stent assembly comprising: a generally tubular frame having a first
end and a second end, the frame defining a central passage and a
central axis; a secondary passage, defined between an inner surface
of the frame and an outer surface of an inner rib closer to the
central axis than the frame; a proximal alignment arm, wherein the
proximal alignment arm is coupled to the frame at the first end of
the frame; and a skirt coupled to the inner rib and the proximal
alignment arm such that a coronary channel is defined between an
outer surface of the skirt and the frame.
13. The stent assembly of claim 12, wherein the stent assembly is
configured to be deployed within an aorta with the proximal
alignment arm deployed in a sinus of an aortic valve.
14. The stent assembly of claim 13, wherein the secondary passage
is generally parallel with the central axis of the frame.
15. The stent assembly of claim 13, wherein the secondary passage
comprises two secondary passages.
16. The stent assembly of claim 13, wherein the proximal alignment
arm extends from a proximal end of the frame, the proximal
alignment arm configured to be deployed in an aortic sinus, the
proximal alignment arm further configured such that a proximal end
of the proximal alignment arm extends below an ostium of a coronary
artery.
17. The stent assembly of claim 13, wherein the proximal alignment
arm comprises two proximal alignment arms.
18. The stent assembly of claim 13, wherein the coronary channel is
configured to rotationally align with an ostium of the coronary
artery.
19. The stent assembly of claim 13, wherein with the stent assembly
deployed in the aorta, the proximal alignment arm encircles an
ostium of a coronary artery, and a coronary pocket is defined
between the outer surface of the skirt and the aortic sinus in
which the proximal alignment arm is disposed.
20. The stent assembly of claim 19, wherein when in the radially
expanded deployed configuration, the coronary channel is in fluid
communication with the coronary pocket and the coronary pocket is
in fluid communication with the coronary artery.
21. A method of implanting a stent assembly at a location of an
aorta comprising the steps of: advancing the stent assembly in a
radially compressed delivery configuration to the location of the
aorta, wherein the stent assembly includes a frame with a central
passage and a central axis, a secondary passage formed between an
inner surface of the frame and an outer surface of an inner rib
closer to the central passage, a proximal alignment arm extending
proximally from a proximal end of the frame, and a skirt coupled to
the inner rib and the proximal alignment arm; rotationally
orienting the stent assembly such that the secondary channel is
generally circumferentially aligned with an ostium of a coronary
artery; and deploying the stent assembly from the radially
compressed delivery configuration to a radially expanded deployed
configuration at the location within the aorta such that the
proximal alignment arm extends into an aortic sinus below the
ostium of the coronary artery and a coronary channel is formed
between an outer surface of the skirt at the inner ribs and an
inner surface of aorta, and a coronary pocket is formed between the
outer surface of the skirt at the proximal alignment arm and an
inner surface of the aortic sinus.
22. The method of claim 21, further comprising the steps of:
delivering a valve component in a radially compressed delivery
configuration to a location within a native aortic valve; and
deploying the valve component such that the valve component expands
from the radially compressed delivery configuration to a radially
expanded deployed configuration.
23. The method of claim 21, wherein the secondary passage comprises
two secondary passages, and wherein the step of rotationally
orienting the stent assembly comprises circumferentially aligning
one of the secondary passages with the ostium of the left coronary
artery and circumferentially aligning the other of the secondary
passages with the right coronary artery.
24. A valve assembly having a radially compressed delivery
configuration and a radially expanded deployed configuration, the
valve assembly comprising: a generally tubular frame having a first
end and a second end, the frame defining a central passage and a
central axis: a prosthetic valve coupled to the frame; a coronary
orifice extending between an inner surface and an outer surface of
the frame; and a coronary arm having a generally tubular structure,
the coronary arm defining a longitudinal passage with a
longitudinal axis, a first end of the coronary arm coupled to the
coronary orifice, the coronary arm having a longitudinally
collapsed delivery configuration wherein a second end of the
coronary arm is adjacent the first end, and a longitudinally
extended deployed configuration wherein the second end is spaced
from the first end.
25. The valve assembly of claim 24, wherein the valve assembly is
configured to be deployed at a native aortic valve.
26. The valve assembly of claim 25, wherein the longitudinal axis
of the coronary arm extends generally transverse to the central
axis of the frame.
27. The valve assembly of claim 25, wherein the coronary arm
comprises two coronary arms.
28. The valve assembly of claim 27, wherein the second end of each
coronary arm is configured to align with an ostium of a respective
coronary artery.
29. The valve assembly of claim 28, wherein the valve assembly is
configured such that when the valve assembly is in the radially
expanded deployed configuration and the coronary arms are in the
longitudinally expanded deployed configuration, the central passage
of the frame is in fluid communication with the longitudinal
passage of each of the coronary arms, and the longitudinal passage
of each of the coronary arms is in fluid communication with the
respective coronary artery.
30. A method of implanting a valve assembly at a location of a
native valve comprising the steps of: advancing the valve assembly
in a radially compressed delivery configuration to the location of
the native valve, wherein the valve assembly includes a generally
tubular frame having a first end and a second end, the frame
defining a central passage and a central axis, a prosthetic valve
coupled to the frame, a coronary orifice extending between an inner
surface and an outer surface of the frame, and a coronary arm
having a generally tubular structure, a first end of the coronary
arm coupled to the coronary orifice of the frame and a second end
of the coronary arm disposed adjacent to the first end with the
coronary arm in a longitudinally collapsed delivery configuration;
rotationally orienting the valve assembly such that the coronary
arm is aligned with an ostium of a coronary artery; deploying the
valve assembly such that the frame expands from the radially
compressed delivery configuration to a radially expanded deployed
configuration with the frame engaging an inner surface of the
native valve and the aortic sinuses; deploying the coronary arm
from the longitudinally compressed delivery configuration to a
longitudinally extended deployed configuration such that the second
end of the coronary arm is extended away from the first end and the
second end is disposed within the coronary artery.
31. The method of claim 30, wherein the valve assembly includes two
coronary arms, and wherein the step of rotationally orienting the
valve assembly comprises aligning one of the two coronary arms with
the left coronary artery and the other of the two coronary arms
with the right coronary artery.
Description
FIELD OF THE INVENTION
[0001] Embodiments hereof relate to heart valve prostheses and
methods for intraluminally deploying heart valve prostheses, and in
particular, to heart valve prostheses including coronary access and
methods of intraluminally delivering and deploying such heart valve
prostheses.
BACKGROUND OF THE INVENTION
[0002] Heart valves, such as the mitral, tricuspid, aortic, and
pulmonary valves, are sometimes damaged by disease or by aging,
resulting in problems with the proper functioning of the valve.
Heart valve problems generally take one of two forms: stenosis in
which a valve does not open completely or the opening is too small,
resulting in restricted blood flow; or insufficiency in which blood
leaks backward across a valve when it should be closed.
[0003] Heart valve replacement has become a routine surgical
procedure for patients suffering from valve regurgitation or
stenotic calcification of the leaflets. Conventionally, the vast
majority of valve replacements entail full sternotomy in placing
the patient on cardiopulmonary bypass. Traditional open surgery
inflicts significant patient trauma and discomfort, requires
extensive recuperation times, and may result in life-threatening
complications.
[0004] To address these concerns, efforts have been made to perform
cardiac valve replacements using minimally invasive techniques. In
these methods, laparoscopic instruments are employed to make small
openings through the patient's ribs to provide access to the heart.
While considerable effort has been devoted to such techniques,
widespread acceptance has been limited by the clinician's ability
to access only certain regions of the heart using laparoscopic
instruments.
[0005] Still other efforts have been focused upon percutaneous
transcatheter (or transluminal) delivery of replacement cardiac
valves to solve the problems presented by traditional open surgery
and minimally invasive surgical methods. In such methods, a valve
prosthesis is compacted for delivery in a catheter and then
advanced, for example through an opening in the femoral artery and
through the descending aorta to the heart, where the prosthesis is
then deployed in the valve annulus (e.g., the aortic valve
annulus).
[0006] Various types and configurations of prosthetic heart valves
are used in percutaneous valve procedures to replace diseased
natural human heart valves. The actual shape and configuration of
any particular prosthetic heart valve is dependent to some extent
upon the valve being replaced (i.e., mitral valve, tricuspid valve,
aortic valve, or pulmonary valve). In general, prosthetic heart
valve designs attempt to replicate the function of the valve being
replaced and thus will include valve leaflet-like structures used
with either bioprostheses or mechanical heart valve prostheses. If
bioprostheses are selected, the replacement valves may include a
valved vein segment or pericardial manufactured tissue valve that
is mounted in some manner within an expandable stent frame to make
a valved stent. In order to prepare such a valve for percutaneous
implantation, one type of valved stent can be initially provided in
an expanded or uncrimped condition, then crimped or compressed
around a balloon portion of a catheter until it is close to the
diameter of the catheter. In other percutaneous implantation
systems, the stent frame of the valved stent can be made of a
self-expanding material. With these systems, the valved stent is
crimped down to a desired size and held in that compressed state
within a sheath, for example. Retracting the sheath from this
valved stent allows the stent to expand to a larger diameter, such
as when the valved stent is in a desired position within a
patient.
[0007] While some problems of traditional open-heart surgery are
overcome by percutaneous transcatheter (transluminal) methods,
there are still risks associated with the method including post
implantation percutaneous coronary intervention, coronary
perfusion, and heart block.
[0008] Post implantation coronary access with traditional
transcatheter valve implantation (TAVI) may be limited by factors
such as implantation height, strut width and cell opening size.
Despite technical efforts to optimize valve prostheses placement,
these factors may limit future access to coronary arteries and
procedures to coronary arteries following transcatheter valve
implementation.
[0009] Coronary perfusion refers to the pressure gradient between
aortic pressure and left ventricle pressure. This gradient drives
blood flow into the coronary arteries. Implantation placement,
height, cell opening size, partial coronary obstruction, and stent
alignment may negatively impact blood flow to the coronary
arteries.
[0010] Heart block is an abnormal heart rhythm where the heart
beats too slowly, called bradycardia. With heart block, the
electrical signals that provide normal heart rhythm are either
partially or totally blocked between the upper and lower heart.
Improper placement of an aortic valve prosthesis is considered a
possible contributor to heart block.
[0011] There is a need for devices and methods that allow for
simultaneous creation of coronary access during transcatheter valve
implementation (TAVI) procedures. There is also a need for devices
and methods to deploy valve prostheses further from the aortic
annulus to minimize heart block in patients undergoing
transcatheter valve implantation (TAVI) procedures.
BRIEF SUMMARY OF THE INVENTION
[0012] Embodiments hereof are related to an anchor stent assembly
to be used with a valve component. The anchor stent assembly has a
radially compressed delivery configuration and a radially expanded
deployed configuration. The stent assembly includes a generally
tubular frame having a first end and a second end, the frame
defining a central passage and a central axis. A secondary passage
is defined between an inner surface of the frame and an outer
surface of an inner rib disposed closer to the central axis than
the frame. An extension tube is disposed through the secondary
passage. The extension tube includes an extension tube lumen having
a first opening at a first end of the extension tube and a second
opening at a second end of the extension tube. The anchor stent
assembly may include two secondary passages with two extension
tubes such that the anchor stent assembly may be deployed in the
aorta and the extension tubes may be circumferentially aligned with
respective ostia of the left and right coronary arteries.
[0013] Embodiments hereof are also directed to a method of
implanting a stent assembly at a location in an aorta. The method
includes advancing the stent assembly in a radially compressed
delivery configuration to the location in the aorta. The stent
assembly includes a generally tubular frame having a first end and
a second end, a central passage, a central axis, a secondary
passage formed between an inner surface of the frame and an outer
surface of an inner rib closer to the central axis than the frame,
and an extension tube extending through the secondary passage, the
extension tube being coupled to the frame and having an extension
tube lumen. The method further includes rotationally orienting the
stent assembly such that the extension tube is generally
circumferentially aligned with an ostium of a coronary artery. The
stent assembly is then deployed from the radially compressed
delivery configuration to a radially expanded deployed
configuration at the location within the aorta. With the stent
assembly in place, a coronary stent is advanced in a radially
compressed delivery configuration through the extension tube lumen
such that a first portion of the coronary stent resides within the
extension tube lumen and a second portion of the coronary stent
extends into the coronary artery. The coronary stent is then
deploying the coronary stent assembly from the radially compressed
delivery configuration to a radially expanded deployed
configuration. The method may further include delivering a valve
component in a radially compressed delivery configuration to a
location within a native aortic valve and deploying the valve
component such that the valve component expands from the radially
compressed delivery configuration to a radially expanded
configuration. The valve component may be situated such that a
portion of the valve component is disposed within the central
passage of the anchor stent assembly when both are deployed.
[0014] Embodiments hereof are also directed to an anchor stent
assembly for use with a valve component. The anchor stent assembly
includes a radially compressed delivery configuration and a
radially expanded deployed configuration. The stent assembly
includes a generally tubular frame having a proximal end and a
distal end and defining a central passage and a central axis. A
secondary passage is defined between an inner surface of the frame
and an outer surface of an inner rib closer to the central axis
than the frame. A proximal alignment arm is coupled to the frame at
the proximal end of the frame. A skirt is coupled to the inner rib
and the proximal alignment arm such that a coronary channel is
defined between an outer surface of the skirt and the frame. In an
embodiment, the secondary passage comprises two secondary passages,
and the stent assembly is configured to be rotationally oriented
such that one of the secondary passages is circumferentially
aligned with an ostium of the left coronary artery and the other of
the secondary passages is circumferentially aligned with an ostium
of the right coronary artery. The portion of the skirt attached to
the proximal alignment arm defines a coronary pocket between the
outer surface of the skirt and the aortic sinus in which the
proximal alignment arm is disposed.
[0015] Embodiments hereof are also directed to a method of
implanting an anchor stent assembly at a location within an aorta.
The anchor stent assembly includes a frame with a central passage
and a central axis, a secondary passage formed between an inner
surface of the frame and an outer surface of an inner rib closer to
the central passage, a proximal alignment arm extending proximally
from a proximal end of the frame, and a skirt coupled to the inner
rib and the proximal alignment arm. The anchor stent assembly is
advanced in a radially compressed delivery configuration to the
location in the aorta. The method includes rotationally orienting
the anchor stent assembly such that the secondary passage is
generally circumferentially aligned with an ostium of a coronary
artery. The method further includes deploying the anchor stent
assembly from the radially compressed delivery configuration to a
radially expanded deployed configuration at the location within the
aorta such that the proximal alignment arm extends into an aortic
sinus below the ostium of the coronary artery and a coronary
channel is formed between an outer surface of the skirt at the
inner rib and an inner surface of aorta, and a coronary pocket is
formed between the outer surface of the skirt at the proximal
alignment arm and an inner surface of the aortic sinus. The method
may further include delivering a valve component in a radially
compressed delivery configuration to a location within a native
aortic valve, and deploying the valve component such that the valve
component expands from the radially compressed delivery
configuration to a radially expanded deployed configuration.
[0016] Embodiments hereof are also directed to a valve assembly
including a generally tubular frame, a prosthetic valve coupled to
the frame, a coronary orifice extending between an inner surface
and an outer surface of the frame, and a coronary arm having a
first end coupled to the coronary orifice. The coronary arm has a
generally tubular structure and defines a longitudinal passage with
a longitudinal axis. The coronary arm includes a longitudinally
collapsed delivery configuration wherein a second end of the
coronary arm is adjacent the first end, and a longitudinally
extended deployed configuration wherein the second end is spaced
from the first end. The prosthetic valve may include two coronary
arms and is configured to be deployed at a native aortic valve such
that one of the coronary arms extends into the left coronary artery
and the other coronary arm extends into the right coronary
artery.
[0017] Embodiments hereof are also directed to a method of
implanting a valve assembly at a location of a native valve. The
valve assembly includes a generally tubular frame defining a
central passage and a central axis. A prosthetic valve is coupled
to the frame. A coronary orifice extends between an inner surface
and an outer surface of the frame. A coronary arm includes a first
end coupled to the coronary orifice of the frame. A second end of
the coronary arm is disposed adjacent to the first end with the
coronary arm in a longitudinally collapsed delivery configuration.
The method includes advancing the valve assembly in a radially
compressed delivery configuration with the coronary arm in the
longitudinally collapsed configuration to the location of the
native valve. The valve assembly is rotationally oriented such that
the coronary arm is aligned with an ostium of a coronary artery.
The valve assembly is deployed such that the frame expands from the
radially compressed delivery configuration to a radially expanded
deployed configuration with the frame engaging an inner surface of
the native valve and the aortic sinuses. The coronary arm is from
the longitudinally compressed delivery configuration to a
longitudinally extended deployed configuration such that the second
end of the coronary arm is extended away from the first end and the
second end is disposed within the coronary artery. The valve
assembly may include two coronary arms, and the method includes
rotationally orienting the valve assembly such that one of the two
coronary arms is aligned with the left coronary artery and the
other of the two coronary arms is aligned with the right coronary
artery.
BRIEF DESCRIPTION OF DRAWINGS
[0018] The foregoing and other features and advantages of the
invention will be apparent from the following description of
embodiments hereof as illustrated in the accompanying drawings. The
accompanying drawings, which are incorporated herein and form a
part of the specification, further serve to explain the principles
of the invention and to enable a person skilled in the pertinent
art to make and use the invention. The drawings are not to
scale.
[0019] FIG. 1 is a schematic illustration of a prior art stented
valve prosthesis.
[0020] FIG. 2 is a schematic illustration of the prior art stented
valve prosthesis of FIG. 1.
[0021] FIG. 3 is a schematic illustration of an anchor stent
assembly in accordance with an embodiment hereof.
[0022] FIGS. 4A and 4B are schematic illustrations of an anchor
stent assembly in accordance with another embodiment hereof.
[0023] FIGS. 5-13 are schematic illustrations of an embodiment of a
method for delivering and deploying a valve prosthesis at an aortic
valve with the anchor stent assembly of FIG. 3 deployed in the
aorta above the aortic sinuses.
[0024] FIGS. 14-19 are schematic illustrations of an embodiment of
a method for delivering and deploying a valve prosthesis at a
native aortic valve with the anchor stent assembly of FIG. 4B
deployed in the aorta above the aortic sinuses.
[0025] FIGS. 20A-20B are schematic illustrations of a valve
prosthesis in accordance with another embodiment hereof.
[0026] FIGS. 21-27 are schematic illustrations of an embodiment of
a method for delivering and deploying the valve prosthesis of FIGS.
20A-20B at an aortic valve.
DETAILED DESCRIPTION OF THE INVENTION
[0027] Specific embodiments of the present invention are now
described with reference to the figures, wherein like reference
numbers indicate identical or functionally similar elements. The
terms "distal" and "proximal" when used in the following
description to refer to a catheter or delivery system are with
respect to a position or direction relative to the treating
clinician. Thus, "distal" and "distally" refer to positions distant
from or in a direction away from the clinician and "proximal" and
"proximally" refer to positions near or in a direction toward the
clinician. When the terms "distal" and "proximal" are used in the
following description to refer to a device to be implanted into a
vessel, such as an anchor stent assembly or valve component, they
are used with reference to the direction of blood flow from the
heart. Thus, "distal" and "distally" refer to positions in a
downstream direction with respect to the direction of blood flow
and "proximal" and "proximally" refer to positions in an upstream
direction with respect to the direction of blood flow.
[0028] FIGS. 1 and 2 show an exemplary conventional valve
prosthesis similar to the Medtronic CoreValve.RTM. transcatheter
aortic valve replacement valve prosthesis and as described in U.S.
Patent Application Publication No. 2011/0172765 to Nguyen et al.
(hereinafter "the '765 publication"), which is incorporated by
reference herein in its entirety. As shown in FIGS. 1 and 2, valve
prosthesis 100 includes an expandable generally tubular frame 102
having a valve body 104 affixed to its interior surface, e.g., by
sutures. Frame 102 preferably comprises a self-expanding structure
formed by laser cutting or etching a metal alloy tube comprising,
for example, stainless steel or a shape memory material such as
nickel titanium. The frame has an expanded deployed configuration,
which is impressed upon the metal alloy tube using techniques known
in the art. Valve body 104 preferably comprises individual leaflets
assembled to a skirt, where all of the components are formed from a
natural or man-made material, including but not limited to,
mammalian tissue, such as porcine, equine or bovine pericardium, or
a synthetic or polymeric material.
[0029] Frame 102 in the exemplary embodiment includes an outflow
section 106, an inflow section 110, and a constriction region 108
between the inflow and outflow sections. Frame 102 may comprise a
plurality of cells having sizes that vary along the length of the
prosthesis. When configured as a replacement for an aortic valve,
inflow section 110 extends into and anchors within the aortic
annulus of a patient's left ventricle and outflow section 106 is
positioned in the patient's ascending aorta. Frame 102 also may
include eyelets 130 for use in loading the heart valve prosthesis
100 into a delivery catheter.
[0030] Valve body 104 may include a skirt 121 affixed to frame 102,
and leaflets 112, 114, 116. Leaflets 112, 114, 116 may be attached
along their bases to skirt 121, for example, using sutures or a
suitable biocompatible adhesive. Adjoining pairs of leaflets are
attached to one another at their lateral ends to form commissures
124, 126, 128, with free edges 118, 120, 122 of the leaflets
forming coaptation edges that meet in an area of coaptation, as
described in the '765 publication and shown in FIG. 2 hereof.
[0031] The following detailed description is merely exemplary in
nature and is not intended to limit the invention or the
application and uses of the invention. Although the description of
the invention is in the context of transcatheter aortic valve
implantation, the invention may also be used in any other body
passageways where it is deemed useful. Furthermore, there is no
intention to be bound by any expressed or implied theory presented
in the preceding technical field, background, brief summary or the
following detailed description.
[0032] FIG. 3 shows an embodiment of an anchor stent assembly 200
including an anchor stent 202 and extension tubes 270. Anchor stent
202 is sized and designed to deploy in the aorta above the aortic
sinuses of a heart, as described in more detail below. Anchor stent
assembly is configured to be used with a valve component, as will
be described in more detail below.
[0033] Anchor stent 202 includes a frame 206 having a first or
proximal end 212, and a second or distal end 210, as shown in FIG.
3. Frame 206 is a generally tubular configuration having a central
passage 208. Frame 206 is a stent structure as is known in the art
and may be self-expanding. Frame 206 includes a first, radially
compressed configuration for delivery and a second, radially
expanded or deployed configuration when deployed at the desired
site. In the radially expanded configuration, frame 206 may have a
diameter that is generally about 2-5 millimeters larger than the
diameter of the location in which the frame is to be installed, in
order to create opposing radial forces between the outward radial
force of the frame against an inward resisting force of the
vessel.
[0034] Frame 206 is constructed of a series of vertical struts or
stringers 220 arranged parallel to a central longitudinal axis LA1
of frame 206. Stringers 220 are spaced radially from the central
longitudinal axis LA1 and are spaced circumferentially from each
other around a circumference of the frame 206. Stringers 220 are
connected by a series of radially collapsible outer struts or ribs
224 that run circumferentially between adjacent stringers 220. The
outer surfaces of outer ribs 224 and the outer surfaces of stringer
220 form the outer surface of frame 206. While the embodiment of
FIG. 3 shows anchor stent 206 with ten (10) stringers 220 connected
by six (6) rows of outer ribs 224, it is not meant to limit the
design, and it is understood that more or fewer stringers 220 and
outer ribs 224 may be provided depending on the specific
requirements of the components, devices, and procedures being
utilized.
[0035] A first extension tube channel or secondary passage 221a is
formed between adjacent stringers 220a and 220b and between outer
ribs 224 and corresponding inner ribs 222 disposed between
stringers 220a and 220b. Inner ribs 222 are disposed closer to
central longitudinal axis LA1 than outer ribs 224 such that first
extension tube channel 221a is formed between outer ribs 224 and
inner ribs 222 and first extension tube channel 221a extends
longitudinally from first end 212 to second end 210 of frame 206.
Similarly, a second extension tube channel or secondary passage
221b is formed between adjacent stringers 220c and 220d and between
outer ribs 224 and corresponding inner ribs 222 disposed between
stringers 220c and 220d. Inner ribs 222 are disposed closer to
central longitudinal axis LA1 than outer ribs 224 such that second
extension tube channel 221b is formed between outer ribs 224 and
inner ribs 222 and second extension tube channel 221b extends from
first end 212 to second end 210 of frame 206. First and second
extension tube channels 221a/221b are spaced apart from each other
around the circumference of frame 206 such that they generally
align with circumferentially with a corresponding coronary artery
when deployed adjacent the aortic sinuses of an aortic valve. Thus,
first and second extension tube channels 221a/221b are generally
spaced circumferentially approximately 120 degrees apart.
[0036] Stringers 220, outer ribs 224 and inner ribs 222 are
collapsible structures and may be constructed of materials such as,
but not limited to, stainless steel, Nitinol, or other suitable
materials for the purposes disclosed herein. Outer ribs 224 and
inner ribs 222 may be connected to stringers 220 by methods such
as, but not limited to fusing, welding, or other methods suitable
for the purposes disclosed herein. Alternatively, frame 206,
including stringers 220, outer ribs 224, and inner ribs 222 may be
formed by cutting a pattern from a tube, such as by laser-cutting,
chemical etching, or other suitable methods. In other embodiments,
the pattern may be cut from a flat sheet of material and then
rolled to form frame 206. Although frame 206 has been described
with stringers 220, outer ribs 224, and inner ribs 222, other
structures may be used to form frame 206, such as, but not limited
to, rings formed from sinusoidally shaped struts, struts forming
cells (such as diamond shaped or hexagonally shaped cells), and
other structures. The details of such structures are not essential
provided that the frame includes a central passage and at least one
secondary passage as described herein.
[0037] Extension tubes 270 are disposed within respective extension
tube channels 221a/221b of frame 206. In the embodiment shown,
extension tubes 270 extend from first end 212 to second end 210 of
frame 206. However, in other embodiments, extension tubes need not
extend the entire length of frame 206. Extension tubes 270 include
a first end 272 adjacent first end 212 of frame 206, and a second
end 274 adjacent second end 210 of anchor frame 206. First end 272
of extension tube 270 may be flared as shown such that the diameter
of first end 272 is greater than the diameter of second end 274.
Each extension tube 270 forms a respective extension tube lumen
276. Extension tube 270 is constructed of materials such as, but
not limited to woven polyester, Dacron mesh, and PTFE (woven, mesh,
or elecrospun), or other materials suitable for the purposes
disclosed herein. Extension tube 270 may be connected to anchor
frame 206 at inner rib contact point 226 and outer rib contact
point 227 and may be attached by methods such as, but not limited
to sutures, adhesives, fusing, welding, or other methods suitable
for the purposes disclosed herein.
[0038] Although the embodiment of FIG. 3 has been shown with
extension tube channels 220a/220b with a respective extension tube
270 disposed therein, both the extension tube channels 220 and
extension tubes 270 are not required. For example, and not by way
of limitation, in another embodiment, extension tube channels 220
are eliminated and extension tubes are attached to an inner surface
of outer ribs 224, In such an embodiment, inner ribs 222 are
eliminated such that extension tube channels 220 are not formed. In
another example, extension tube channels 220 are formed, but
extension tubes 270 are not disposed therein. Instead, respective
coronary stents, as described in more detail below, may extend
through extension tube channels 220. In such an embodiment, it is
preferable that the coronary stents are covered stents or stent
grafts.
[0039] Another embodiment of an anchor stent assembly 300 is shown
in FIGS. 4A and 4B. Anchor stent assembly 300 includes an anchor
stent 302 including proximal alignment arms and a skirt to form
coronary pockets, as described in more detail below. Anchor stent
302 is sized and configured to be deployed within the aorta, above
the aortic sinuses of a heart, with the proximal alignment arms
extending into aortic sinuses, as described in more detail
below.
[0040] Anchor stent 302 includes a frame 306 having a first or
proximal end 312, and a second or distal end 310, as shown in FIGS.
4A and 4B. Frame 306 is a generally tubular configuration having a
central passage 308. Frame 306 is a stent structure as is known in
the art and may be self-expanding. Frame 306 includes a first,
radially compressed configuration for delivery and a second,
radially expanded or deployed configuration when deployed at the
desired site. Frame 306 may be constructed of materials such as,
but not limited to, stainless steel, Nitinol, or other suitable
materials for the purposes disclosed herein. In the radially
expanded configuration, frame 306 may have a diameter that is
generally about 2-5 millimeters larger than the diameter of the
location in which the frame is to be installed, in order to create
opposing radial forces between the outward radial force of the
frame against an inward resisting force of the vessel.
[0041] Frame 306 is constructed of a series of vertical struts or
stringers 320 360 arranged parallel to a central longitudinal axis
LA2 of frame 306. Stringers 320 are spaced radially from the
central longitudinal axis LA2 and are spaced circumferentially from
each other around the circumference of frame 306. Stringers 320 are
connected by a series of radially collapsible outer struts or ribs
324 that run circumferentially between adjacent stringers 320. The
outer surfaces of outer ribs 324 and the outer surfaces of
stringers 320 for the outer surface of frame 306. While the
embodiment of FIG. 4A shows anchor stent 302 with ten (10)
stringers 320 connected by six (6) rows of outer ribs 324, it is
not meant to limit the design, and it is understood that more or
fewer stringers 320 and outer ribs 324 may be provided depending on
the specific requirements of the components, devices, and
procedures being utilized.
[0042] A first extension channel or secondary passage 321a is
formed between adjacent stringers 320a and 320b and between outer
ribs 324 and corresponding inner ribs 322 disposed between
stringers 320a and 320b. Inner ribs 322 are disposed closer to
central longitudinal axis LA2 than outer ribs 324 such that first
extension channel 321a is formed between outer ribs 324 and inner
ribs 322 and first extension channel 321a extends longitudinally
from first end 310 to second end 312. Similarly, a second extension
channel or secondary passage 321b is formed between adjacent
stringers 320c and 320d and between outer ribs 324 and
corresponding inner ribs 322 disposed between stringers 320c and
320d. Inner ribs 322 are disposed closer to central longitudinal
axis LA1 than outer ribs 324 such that second extension channel
321b is formed between outer ribs 324 and inner ribs 322 and second
extension channel 321b extends from first end 312 to second end 310
of frame 306. First and second extension channels 321a/321b are
spaced apart from each other around the circumference of frame 306
such that they generally align circumferentially with a
corresponding coronary artery when deployed adjacent the aortic
sinuses of an aortic valve. Thus, first and second channels
321a/321b are generally spaced circumferentially approximately 120
degrees apart.
[0043] As described above, frame 306 is generally similar to frame
206 of FIG. 3. As explained with respect to frame 206, stringers
320, outer ribs 324 and inner ribs 322 of frame 306 are collapsible
structures such as wire and may be constructed of materials such
as, but not limited to, stainless steel, Nitinol, or other suitable
materials for the purposes disclosed herein. Outer ribs 324 and
inner ribs 322 may be connected to stringers 320 by methods such
as, but not limited to fusing, welding, or other methods suitable
for the purposes disclosed herein. Alternatively, frame 306,
including stringers 320, outer ribs 324, and inner ribs 322 may be
formed by cutting a pattern from a tube, such as by laser-cutting,
chemical etching, or other suitable methods. In other embodiments,
the pattern may be cut from a flat sheet of material and then
rolled to form frame 306. Although frame 306 has been described
with stringers 320, outer ribs 324, and inner ribs 322, other
structures may be used to form frame 306, such as, but not limited
to, rings formed from sinusoidally shaped struts, struts forming
cells (such as diamond shaped or hexagonally shaped cells), and
other structures. The details of such structures are not essential
provided that the frame includes a central passage and at least one
extension channel as described herein.
[0044] Anchor stent 302 further includes proximal alignment arms
362, 364, and 366 extending proximally from first end 312 of frame
306. In the embodiment shown in FIGS. 4A and 4B, each proximal
alignment arm 362, 364, and 366 is in the form of a wire loop with
first and second ends of the wire attached to frame 306. In
particular, first arm 362 includes first and second ends attached
to frame 306 at connections 361 and 363 respectively, as shown in
FIG. 4A. Similarly, second arm 364 includes first and second ends
attached to frame 306 at connections 365 and 367, respectively, and
third arm 366 includes first and second ends attached to frame 306
at connections 369 and 371, respectively. Connections 361, 363,
365, 367, 369, and 371 may be formed by the material of proximal
alignment arms 362, 364, and 366, and frame 306 being fused or
welded together. Alternatively, the connections may be mechanical
connections such as, but not limited to, sutures or otherwise tied,
a crimp connector to crimp ends of the arms to frame 306, or other
suitable connections. Proximal alignment arms 362, 364, and 366
include a radially compressed configuration for delivery to the
treatment site and a radially expanded or deployed configuration.
In the radially expanded configuration, proximal alignment arms
362, 364, and 366 have a combined diameter such that they fit into
the aortic sinuses. For example, and not by way of limitation, in
the radially expanded configuration, the combined diameter of
proximal alignment arms 362, 364, and 366 may be in the range of 29
mm-39 mm. As shown in FIGS. 4A and 4B, in the radially expanded
configuration, proximal alignment arms 362, 364, and 366 flare
outwardly from first end 312 of frame 306. Although FIG. 4A shows
three (3) proximal alignment arms with connections approximately
equally spaced around the circumference of frame 306, more or fewer
arms may be utilized, and the arms need not be equally spaced
around the circumference of frame 306. At least two of the proximal
alignment arms (364 and 366 in FIG. 4A) are configured such that
they encircle, but do not obstruct, the left and right ostia of the
coronary arteries, as described in more detail below.
[0045] Anchor stent assembly 300 further includes a skirt 380
attached to an inside surface thereof to separate central passage
308 from extension channels 321a and 321b, as shown in FIG. 4B. As
shown in FIG. 4B, skirt 380 has a second end 372 coupled to second
end 310 of anchor frame 306 and a first end 374 coupled to proximal
alignment arms 362, 364, and 366. An outer surface of skirt 380
forms a coronary pocket 382 at each of proximal alignments arms
362, 364, 366. The coronary pocket 382 formed with skirt 380 and
proximal alignment arm 364 is generally longitudinally aligned with
extension channel 321b. The coronary pocket 382 formed with skirt
380 and proximal alignment arm 366 (not shown in FIG. 4B) is
generally longitudinally aligned with extension channel 321a.
Coronary pockets 382 encircle the left and right coronary ostia
when anchor stent assembly 300 is in the radially expanded
configuration at the desired deployment site, as shown in more
detail below. Skirt 380 is a generally cylindrical tube constructed
of cloth or fabric material. The fabric may comprise any suitable
material including, but not limited to, woven polyester such as
polyethylene terephthalate, polytetrafluoroethylene (PTFE), or
other biocompatible materials. Skirt 380 is secured to frame 306
and the proximal alignment arms in a manner such as, but not
limited to, sutures, laser or ultrasonic welding, or other methods
suitable for the purposes disclosed herein. In another embodiment,
first end 374 of skirt 380 may be coupled to first end 312 of frame
306 such that skirt 380 does not extend proximally to the proximal
alignment arms. In such an embodiment, extension channels 321a,
321b are generally circumferentially aligned with the coronary
ostia, but disposed above the ostia, and the proximal alignment
arms 364, 366 encircle the ostia to assist in prevent blockage
thereof by a valve component, described in more detail below.
[0046] With anchor stent assembly deployed with frame 306 in the
aorta and proximal alignment arms 362, 364, 366 disposed within the
aortic sinuses, skirt 380 is configured such that the wall of the
aortic sinuses and skirt 380 attached to frame 306 and inner ribs
322 enclose extension channels 321 such that each extension channel
321 and corresponding coronary pocket 382 forms a coronary channel
376 for direct path for blood flow to the left or right coronary
ostia.
[0047] An embodiment of a method of delivering and deploying an
anchor stent assembly and a corresponding valve component is
schematically represented in FIGS. 5-13. FIGS. 5-13 describe the
method with respect to anchor stent assembly 200 of FIG. 3. FIGS.
5-13 are not drawn to scale regarding relative lengths of anchor
stent assembly 200 and the valve component. The valve component is
identified herein as valve component 240. Valve component 240 is
generally includes a prosthetic valve 250 attached to a frame 242
(shown schematically in FIG. 13). The combination of frame 242 and
prosthetic valve 250 can assume various configurations. For
example, and not by way of limitation, valve component 240 may be
similar to valve prosthesis 100 shown in FIGS. 1-2. Further, valve
component 240 may be similar to the valve component described in
U.S. Patent Application Publication No. 2015/0119974, including a
common inventor herewith and assigned to Medtronic, Inc., the
contents of which are incorporated by reference herein in their
entirety.
[0048] In the method, a guidewire 502 is advanced distally, i.e.,
away from the clinician, through the aorta 400, past the
sinotubular junction 414, and into the aortic sinuses 412 in the
region of the aortic valve 416 and annulus 418, as shown in FIG. 5.
Guidewire 502 may be introduced through an opening or arteriotomy
through the wall of femoral artery in the groin region of the
patient by methods known to those skilled in the art, such as, but
not limited to, the Seldinger technique. Guidewire 502 is advanced
into the descending (or abdominal) aorta (not shown), the aortic
arch (not shown), and the ascending aorta 402, as shown in FIG. 5.
FIG. 5 also shows two coronary arteries 420 and their corresponding
coronary ostia 422. Although FIGS. 5-13 show a retrograde
percutaneous femoral procedure, it is not meant to limit the method
of use and other procedural methods may be used. For example, and
not by way of limitation, retrograde percutaneous implantation via
subclavian/axillary routes, direct apical puncture, and the use of
direct aortic access via either ministernotomy or right anterior
thoracotomy may also be used.
[0049] FIG. 6 shows a delivery system 500 for delivering anchor
stent assembly 200 being advanced distally, i.e., away from the
clinician, over guidewire 502 to a location in ascending aorta 402
adjacent the aortic sinuses 412. Delivery system 500 may be any
suitable delivery system for delivering stents and/or stent grafts.
In the embodiment shown schematically, anchor stent assembly 200
includes a self-expanding anchor stent 202 and extension tubes 270.
Accordingly, delivery system 500 generally includes an inner or
guidewire shaft 508, which includes a guidewire lumen (not shown)
for receiving guidewire 502. A proximal end of guidewire 502 may be
back loaded into the guidewire lumen (not shown) of inner shaft 508
through a distal opening (not shown) in inner shaft 508. Delivery
system 500 may be an over-the-wire type catheter, or a rapid
exchange catheter, or other catheter devices. Delivery system 500
further generally may include a distal tip 501, an outer sheath 504
that maintains anchor stent assembly 200 in the radially compressed
or delivery configuration during intraluminal delivery through the
vasculature, as shown in FIG. 6, and may also include a pusher or
stopper 506, and other features. Delivery system 500 and/or anchor
stent assembly 200 may also include, for example, radiopaque
markers such that the clinician may determine when delivery system
500 and/or anchor stent assembly 200 is in the proper location and
alignment for deployment.
[0050] Once delivery system 500 has been advanced to the desired
location, such as when first end 212 of anchor stent 202 is
generally aligned with sinotubular junction 414, and extension
tubes 270 rotationally aligned with coronary ostia 422, outer
sheath 504 is retracted proximally, i.e., towards the clinician, as
shown in FIG. 7. As outer sheath 504 is retracted, frame 206 of
anchor stent 202 expands radially outward, engaging the inner wall
of the ascending aorta 402, as shown in FIG. 7.
[0051] Outer sheath 504 is further retracted proximally, i.e.,
towards the clinician, to complete deployment of anchor stent
assembly 200 from outer sheath 504. In other words, sheath 504 is
retracted such that anchor stent assembly 200 is no longer
constrained by sheath 504.
[0052] With anchor stent assembly 200 fully deployed, delivery
system 500 may be retracted proximally, i.e., towards the
clinician, and removed in a manner consistent with current
procedures known to those in the art. Anchor stent assembly 200
remains in the fully deployed configuration with extension tubes
270 generally rotationally aligned with, but not obstructing
coronary ostia 422, as shown in FIG. 8.
[0053] A steerable catheter 530 is advanced distally, i.e., away
from the clinician and into one of extension tubes 270, as shown in
FIG. 9. Steerable catheter 530 is guided into and through extension
tube 270 and into coronary ostium 422 and coronary artery 420.
Guidance may occur from one of several methods including, but not
limited to, x-ray fluoroscopy, ultrasound imaging, electromagnetic
tracking, radiopaque markers, or other methods suitable for the
purposes disclosed herein.
[0054] Once in place within extension tube 270 and coronary artery
420, a guidewire 502 is extended through catheter 530. With
guidewire 502 positioned through extension tube 270 and into
coronary artery 420, steerable catheter 530 is retracted
proximally, i.e., toward the clinician, and removed in a manner
consistent with current procedures known to those in the art.
Guidewire 502 remains disposed through extension tube 270 and into
coronary artery 420, as shown in FIG. 10.
[0055] A coronary stent delivery system 550 for delivering a
coronary stent 552 is advanced distally, i.e., away from the
clinician, over guidewire 502 to a location in the coronary artery
420 via coronary ostium 422, as shown in FIG. 11. Delivery system
550 may be any suitable delivery system for delivering coronary
stents and/or stent grafts as is known in the art. In the
embodiment shown schematically, coronary stent 552 is a
balloon-expandable stent including a graft (i.e., a
balloon-expandable stent graft), but other types of stents may be
used (e.g., self-expanding, uncovered, etc.). Accordingly, delivery
system 550 generally may include a guidewire shaft (not shown), a
distal tip (not shown), and a balloon (not shown) on which coronary
stent 552 is disposed in a radially compressed or delivery
configuration during intraluminal delivery, as shown in FIG. 11.
Coronary stent delivery system 550 may also include other features,
for example, radiopaque markers such that the clinician may
determine when delivery system 550 and/or coronary stent 552 is in
the proper location for deployment.
[0056] Once delivery system 550 has been advanced to the desired
location, the balloon is inflated, causing coronary stent 552 to
expand radially outward, engaging the inner wall of extension tube
270 and inner wall of coronary artery 420, as shown in FIG. 12.
Coronary stent delivery system 550 is retracted proximally, i.e.,
toward the clinician, and removed in a manner consistent with
procedures known to those in the art. The same method described
above is repeated for the other coronary artery 420 to deliver and
deploy a second coronary stent 552. Thus, in FIG. 12, two coronary
stents 552 are shown deployed partially within a respective
coronary artery 420 and partially within a respective extension
tube 270.
[0057] Valve component 240 may now be delivered and deployed at the
native aortic valve 416 using methods and procedures known in the
art. As shown in FIG. 13, valve component 240 may include a
prosthetic valve 250 disposed within valve a frame 242. As also
shown in FIG. 13, frame 242 of valve component 240 may overlap with
ostia 422 of the coronary arteries 420 without being concerned with
blocking flow to the coronary arteries. This is so because blood
flow to the coronary arteries flows through extension tubes 270 and
coronary stents 552 into coronary arteries 420. This also provides
an increased landing zone for the valve component. Any location
between the annulus and before which the native valve leaflets are
no longer captured by the valve frame is a valid landing zone for
the proximal (i.e., inflow) end of the valve frame. Thus, the valve
frame could be placed farther away from the annulus which may
result in less incidence of heart block. Further, a fully skirted
valve component may be used, which may result in less paravalvular
leakage (PVL), without blocking flow to the coronary arteries.
Further, if future procedures are required in a coronary artery
(balloon angioplasty, stent placement, etc.), access to the
coronary arteries may be achieved through the coronary stents 552.
Further, although not shown in FIG. 13, frame 242 of valve
component 240 may extend into the ascending aorta such that frame
242 is disposed within central passage 208 of frame 206 of anchor
stent 202, as explained in more detail in U.S. Patent Application
Publication No. 2015/0119974 assigned to Medtronic, Inc., the
contents of which are incorporated by reference herein in their
entirety.
[0058] FIGS. 14-19 show schematically a method of delivering and
deploying anchor stent assembly 300 of FIG. 4B and a valve
component. FIGS. 14-19 are not drawn to scale regarding relative
lengths of anchor stent assembly 300 and valve component 240.
[0059] Similar to the description above, guidewire 502 is advanced
distally, i.e., away from the clinician, through the aorta 400,
past the sinotubular junction 414, and into the aortic sinuses 412
in the region of the aortic valve 416 and annulus 418, as shown in
FIG. 14. Guidewire 502 may be introduced through an opening or
arteriotomy through the wall of femoral artery in the groin region
of the patient by methods known to those skilled in the art, such
as, but not limited to, the Seldinger technique. Guidewire 502 is
advanced into the descending (or abdominal) aorta (not shown), the
aortic arch (not shown), and the ascending aorta 402, as shown in
FIG. 14. Although FIGS. 14-19 show a retrograde percutaneous
femoral procedure, it is not meant to limit the method of use and
other procedural methods may be used. For example, and not by way
of limitation, retrograde percutaneous implantation via
subclavian/axillary routes, direct apical puncture, and the use of
direct aortic access via either ministernotomy or right anterior
thoracotomy may also be used.
[0060] A delivery system 500 for delivering anchor stent assembly
300 being advanced distally, i.e., away from the clinician, over
guidewire 502 to a location in the aortic sinuses 412, as shown in
FIG. 15. Delivery system 500 may be any suitable delivery system
for delivering stents and/or stent grafts. In the embodiment shown
schematically, anchor stent 302 of anchor stent assembly 300 is a
self-expanding stent. Accordingly, delivery system 500 generally
includes an inner or guidewire shaft 508, which includes a
guidewire passage (not shown) for receiving guidewire 502. A
proximal end of guidewire 502 may be back loaded into the guidewire
passage (not shown) of inner shaft 508 through a distal opening
(not shown) in inner shaft 508. Delivery system 500 may be an
over-the-wire type catheter, or a rapid exchange catheter, or other
catheter devices. Delivery system 500 further generally may include
a distal tip 501, an outer sheath 504 that maintains anchor stent
302 in the radially compressed or delivery configuration during
intraluminal delivery through the vasculature, as shown in FIG. 15,
and may also include a pusher or stopper 506, and other features.
Delivery system 500 and/or anchor stent assembly 300 may also
include, for example, radiopaque markers such that the clinician
may determine when delivery system 500 and/or anchor stent assembly
300 is in the proper location and alignment for deployment.
[0061] Once delivery system 500 has been advanced to the desired
location, such as when first end 312 of frame 306 of anchor stent
302 is generally aligned with sinotubular junction 414, and
proximal alignment arms 364 and 366 are rotationally aligned with
and encircle, but do not obstruct, coronary ostia 422, outer sheath
504 is retracted proximally, i.e., towards the clinician, as shown
in FIG. 16. As outer sheath 504 is retracted, proximal alignment
arms 362 (not shown), 364 (not shown), and 366 engage the inner
wall of the aortic sinuses 412, and frame 306 of anchor stent 302
expands radially outward, engaging the inner wall of ascending
aorta 402, as shown in FIG. 16.
[0062] Outer sheath 504 is further retracted proximally, i.e.,
towards the clinician, to complete deployment of anchor stent
assembly 300 from outer sheath 504. In other words, sheath 504 is
retracted such that anchor stent assembly 300 is no longer
constrained by sheath 504.
[0063] With anchor stent assembly 300 fully deployed, delivery
system 500 may be refracted proximally, i.e., towards the
clinician, and removed in a manner consistent with procedures known
to those in the art. Anchor stent assembly 300 remains in the fully
deployed configuration such that extension channels 321a/321b are
generally rotationally aligned with respective coronary ostia 422
and proximal arms 364 and 366 encircle, but do not obstruct
coronary ostia 422, as shown in FIG. 17 (with skirt removed for
clarity) and FIG. 18 (with skirt 380 in place). Skirt 380, when
anchor stent assembly 300 is in the expanded deployed
configuration, defines extension channels 321 and coronary pockets
382 between an outer surface of skirt 380 and the inner surface of
the wall of the ascending aorta/aortic sinuses, providing
unrestricted blood flow to coronary artery 420, as indicated by
coronary blood flow direction arrow 386 of FIG. 18. Because
coronary pockets 283 are relatively large, extension channels
321a/321b do not need to be perfectly rotationally aligned with the
corresponding coronary ostia 422 and blood will still funnel to the
coronary ostia 422 and into the coronary artery 420.
[0064] Valve component 240, as described above, may now be
delivered and deployed at the native aortic valve 416 using methods
and procedures known in the art. Once in place, prosthetic valve
350 resides within valve frame 342 at annulus 418 as shown in FIG.
19. As also shown in FIG. 13, frame 242 of valve component 240 may
overlap with ostia 422 of the coronary arteries 420 without being
concerned with blocking flow to the coronary arteries. This is so
because blood flow to the coronary arteries flows through extension
channels 321a/321b and coronary pockets 382 into coronary arteries
420. This also provides an increased landing zone for the valve
component. Any location between the annulus and before which the
native valve leaflets are no longer captured by the valve frame is
a valid landing zone for the proximal (i.e., inflow) end of the
valve frame. Thus, the valve frame could be placed farther away
from the annulus which may result in less incidence of heart block.
Further, a fully skirted valve component may be used, which may
result in less paravalvular leakage (PVL), without blocking flow to
the coronary arteries. Further, if future interventional procedures
are required in a coronary artery (balloon angioplasty, stent
placement, etc.), access to the coronary arteries may be achieved
through extension channels 321. Further, although not shown in FIG.
19, frame 242 of valve component 240 may extend into the ascending
aorta such that frame 242 is disposed within central passage 308 of
frame 306 of anchor stent 302, as explained in more detail in U.S.
Patent Application Publication No. 2015/0119974 assigned to
Medtronic, Inc., the contents of which are incorporated by
reference herein in their entirety.
[0065] FIGS. 20A and 20B show an embodiment of an integrated valve
assembly 600 including a frame 606, a prosthetic valve 620, and
coronary arms 650. Valve assembly 600 is sized and designed to
deploy within the aortic sinuses and annulus of a heart, as
described in more detail below.
[0066] Frame 606 includes a first end 612 and a second end 610, as
shown in FIGS. 20A and 20B. Frame 606 is a generally tubular
configuration having a central passage 608 and a central
longitudinal axis LA3. Frame 606 is a stent structure as is known
in the art and may be self-expanding. Frame 606 a coronary orifice
660 between an inner surface and an outer surface of frame 606.
Coronary orifice 660 is an opening through the wall of frame 606.
Coronary orifice 660 may be a separate opening or may be an opening
defined by cells in frame 606. Coronary orifice 660 is described in
more detail below in the description of coronary arms 650.
Generally, frame 606 includes a first, radially compressed
configuration for delivery and a second, radially expanded or
deployed configuration when deployed at the desired site. Frame 606
is a collapsible structure and may be constructed of materials such
as, but not limited to, stainless steel, Nitinol, cobalt-chromium
alloys, or other suitable materials for the purposes disclosed
herein.
[0067] Each coronary arm 650 is a generally tubular structure,
defining a longitudinal passage 658 with a longitudinal axis LA4.
Longitudinal axis LA4 is generally transverse to longitudinal axis
LA3. Although longitudinal axis LA4 has been defined with respect
to one of the coronary arms 650, those skilled in the art would
recognize that the coronary arms do not need to align with each
other. Instead, coronary arms 650 extend from frame 606 at
locations such that coronary arms 650 can extend into a respective
coronary artery, as described in more detail below. Thus, coronary
arms 650 may be longitudinally offset, if appropriate. Coronary
arms 650 may include struts 651 coupled to graft material 652,
similar to a stent-graft construction. Struts 651 may be any
suitable material generally used in stent, such as, but not limited
to, stainless steel or Nitinol. Struts 651 may be the same material
as frame 606. Graft material 652 may be any suitable material
generally used for a graft such as, but not limited to, woven
polyester such as polyethylene terephthalate,
polytetrafluoroethylene (PTFE), other polymers, or other
biocompatible materials. Graft material 652 and struts 651 may be
coupled by sutures, fusion, or other coupling methods known in the
art. Further, graft material 652 may be coupled to the outer
surface or inner surface of struts 651. Coronary arms 650 may be
coupled to frame 606 by fusion, laser or ultrasonic welding,
mechanical connections such as sutures, or other methods suitable
for the purposes disclosed herein. In another embodiment, struts
651 of coronary arms 650 may be constructed integrally with frame
606.
[0068] Coronary arms 650 have a first end 656 and a second end 654,
and a longitudinally collapsed delivery configuration and a
longitudinally extended deployed configuration. When in the
longitudinally collapsed delivery configuration, second end 654 is
adjacent to first end 656, as shown in FIG. 20B. When in the
longitudinally extended deployed configuration, second end 654 is
spaced from first end 656, as shown in FIG. 20A. Thus, as
described, coronary arms 650 telescope from the longitudinally
collapsed delivery configuration to the longitudinally extended
deployed configuration. Coronary arms 650 may be of any length
suitable for the purposes disclosed herein. For example, and not by
way of limitation, coronary arms 650 may have a length in the range
of 15 mm-300 mm.
[0069] Coronary arms 650 are configured such that the longitudinal
axis of each coronary arm 650 generally aligns with a corresponding
longitudinal axis of the coronary artery into which it is to be
inserted.
[0070] While the embodiment of FIGS. 20A-20B shows telescoping
coronary arms 650 as series of circular struts 651 coupled to graft
material 652 to form concentrically connected cylinders, it is not
meant to limit the design, and it is understood that other
materials and configurations may be employed such that depending on
the specific requirements of the components, devices, and
procedures.
[0071] Prosthetic valve 620 may be any prosthetic valve. For
example, and not by way of limitation, prosthetic valve 620 may be
similar to valve body 104 described above with respect to FIGS. 1
and 2, or as described in the '765 publication. Prosthetic valve
620 is coupled to and disposed within frame 606 of valve assembly
600.
[0072] A method of delivering and deploying valve assembly 600 in
accordance with an embodiment hereof is schematically represented
in FIGS. 21-27. As shown in FIG. 21, a guidewire 702 advanced
distally, i.e., away from the clinician, through the aorta 400,
past the sinotubular junction 414, and into the aortic sinuses 412
in the region of the aortic valve 416 and annulus 418. Guidewire
702 may be introduced through an opening or arteriotomy through the
wall of femoral artery in the groin region of the patient by
methods known to those skilled in the art, such as, but not limited
to, the Seldinger technique. Guidewire 702 is advanced into the
descending (or abdominal) aorta (not shown), the aortic arch (not
shown), and the ascending aorta 402, as shown in FIG. 21. Two
coronary arteries 420 and their corresponding coronary ostia 422
are also shown in FIG. 21. Although FIGS. 21-27 show a retrograde
percutaneous femoral procedure, it is not meant to limit the method
of use and other procedural methods may be used. For example, and
not by way of limitation, retrograde percutaneous implantation via
subclavian/axillary routes, direct apical puncture, and the use of
direct aortic access via either ministernotomy or right anterior
thoracotomy may also be used.
[0073] A delivery system 700 for delivering valve assembly 600 is
advanced distally, i.e., away from the clinician, over guidewire
702 to a location at the annulus 418 of the heart, as shown in FIG.
22. Delivery system 700 may be any suitable delivery system for
delivering stents and/or stent grafts. In the embodiment shown
schematically, valve assembly 600 is a self-expanding frame 606.
Accordingly, delivery system 700 generally includes an inner or
guidewire shaft 708, which includes a guidewire passage (not shown)
for receiving guidewire 702. A proximal end of guidewire 702 may be
back loaded into the guidewire passage (not shown) of inner shaft
708 through a distal opening (not shown) in inner shaft 708.
Delivery system 700 may be an over-the-wire type catheter, or a
rapid exchange catheter, or other catheter devices. Delivery system
700 further generally may include a distal tip 701, an outer sheath
704 that maintains valve assembly 600 in the radially compressed or
delivery configuration during intraluminal delivery through the
vasculature, as shown in FIG. 22 and may also include a pusher or
stopper 706, and other features. Delivery system 700 and/or valve
assembly 600 may also include, for example, radiopaque markers such
that the clinician may determine when delivery system 700 and/or
valve assembly 600 is in the proper location and alignment for
deployment.
[0074] Once delivery system 700 has been advanced to the desired
location such that each coronary arm 650 is generally rotationally
and longitudinally aligned with the corresponding coronary ostium
422 of the corresponding coronary artery 420, outer sheath 704 is
retracted proximally, i.e., towards the clinician, to deploy frame
606 of valve assembly 600, as shown in FIG. 23. As frame 606
expands radially outward, frame 606 separates the native leaflets
of aortic valve 416.
[0075] Outer sheath 704 is further retracted proximally, i.e.,
towards the clinician, to complete deployment of valve assembly 600
from outer sheath 704. Sheath 704 is retracted such that valve
assembly 600 is no longer constrained by sheath 704 and expands
radially outward, as shown in FIG. 24.
[0076] With valve assembly 600 fully deployed, delivery system 700
may be retracted proximally, i.e., towards the clinician, and
removed in a manner consistent with procedures known to those in
the art. Valve assembly 600 remains in the fully deployed
configuration with coronary arms 650 in the longitudinally
collapsed delivery configuration and aligned of the corresponding
coronary arteries 420, as shown in FIG. 24.
[0077] A steerable catheter or pushrod 730 is advanced distally,
i.e., away from the clinician and into one coronary arms 650, as
shown in FIG. 25. Pushrod 730 may be guided by x-ray fluoroscopy,
ultrasound imaging, electromagnetic tracking, radiopaque markers,
or other methods suitable for the purposes disclosed herein.
[0078] Once in place within telescoping coronary arm 650, pushrod
730 is advanced distally i.e., away from the clinician, such that
distal end 732 of pushrod 730 engages second end 654 of coronary
arm 650 and pushes second end 654 of coronary arm 650. Pushrod 730
continues to be advanced to extend second end 654 of coronary arm
650 into coronary artery 420, thereby deploying coronary arm 650
from its longitudinally collapsed delivery configuration to its
longitudinally extended deployed configuration, as shown in FIG.
26. In another embodiment, a pushrod may be part of delivery system
700 such that a separate pushrod is not needed.
[0079] Once coronary arm 650 is in its longitudinally extended
deployed configuration with second end 654 of coronary arm 650
disposed within coronary artery 420, steerable catheter 730 is
retracted proximally, i.e., toward the clinician, and removed in a
manner consistent with procedures known to those in the art. The
procedure is repeated for the other coronary arm 650.
[0080] In another embodiment, coronary arms 650 may be formed of
shape memory material such that they are self-extending.
Accordingly, the pre-formed shape of each coronary arm 650 is the
longitudinally extended deployed configuration. The coronary arms
650 are collapsed to the longitudinally collapsed delivery
configuration when loaded into outer sheath 704. When outer sheath
704 is retracted, as described above, coronary arms 650 return to
their pre-formed, longitudinally extended configuration without the
use of the pushrod 730 described above.
[0081] Valve assembly 600 is shown in a fully deployed
configuration shown in FIG. 27. Valve assembly 600 with coronary
arms 650 maintains blood flow to the coronary arteries. Further,
coronary arms 650 provide support for frame 606 when coronary arms
650 are deployed in the coronary arteries. Thus, frame 606 is not
required to provide as much radial force to maintain frame 606 at
the desired location as compared to prosthetic valve assemblies
without coronary arms 650. Further, coronary arms 650 provide
access to the coronary arteries for future interventional
procedures (e.g., balloon angioplasty, stent placement).
[0082] While various embodiments according to the present invention
have been described above, it should be understood that they have
been presented by way of illustration and example only, and not
limitation. It will be apparent to persons skilled in the relevant
art that various changes in form and detail can be made therein
without departing from the spirit and scope of the invention. Thus,
the breadth and scope of the present invention should not be
limited by any of the above-described exemplary embodiments, but
should be defined only in accordance with the appended claims and
their equivalents. It will also be understood that each feature of
each embodiment discussed herein, and of each reference cited
herein, can be used in combination with the features of any other
embodiment
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