U.S. patent application number 12/776136 was filed with the patent office on 2010-08-26 for method for replacing native valve function of a diseased aortic valve.
This patent application is currently assigned to Medtronic Vascular, Inc.. Invention is credited to William E. Cohn, Todd F. Davenport, Gregory H. Lambrecht, John R. LIDDICOAT, Daniel C. Taylor, Steven B. Woolfson.
Application Number | 20100217384 12/776136 |
Document ID | / |
Family ID | 22802236 |
Filed Date | 2010-08-26 |
United States Patent
Application |
20100217384 |
Kind Code |
A1 |
LIDDICOAT; John R. ; et
al. |
August 26, 2010 |
Method For Replacing Native Valve Function Of A Diseased Aortic
Valve
Abstract
Methods for replacing native valve function of a diseased aortic
valve are disclosed. In an embodiment, a method for replacing
native valve function of a diseased aortic valve in a patient
includes: (a) receiving an artificial heart valve assembly mounted
about a first mounting position on a catheter system, (b) guiding
the artificial heart valve assembly through the vasculature of the
patient, (c) while the catheter system having the artificial heart
valve assembly mounted thereto is in the patient's vasculature,
mounting the artificial heart valve assembly about a second
mounting position on the catheter system, (d) delivering the
artificial heart valve assembly to the region of the diseased
aortic valve, (e) expanding the artificial heart valve assembly in
the region of the diseased aortic valve, and (f) withdrawing the
catheter system from the patient's vasculature.
Inventors: |
LIDDICOAT; John R.;
(Sewickley, PA) ; Lambrecht; Gregory H.; (Natick,
MA) ; Davenport; Todd F.; (Andover, MA) ;
Cohn; William E.; (Chestnut Hill, MA) ; Woolfson;
Steven B.; (Boston, MA) ; Taylor; Daniel C.;
(Brighton, MA) |
Correspondence
Address: |
Medtronic CardioVascular
Mounds View Facility South, 8200 Coral Sea Street N.E.
Mounds View
MN
55112
US
|
Assignee: |
Medtronic Vascular, Inc.
Santa Rosa
CA
|
Family ID: |
22802236 |
Appl. No.: |
12/776136 |
Filed: |
May 7, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10895272 |
Jul 20, 2004 |
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12776136 |
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|
09896259 |
Jun 29, 2001 |
6769434 |
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10895272 |
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60215245 |
Jun 30, 2000 |
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Current U.S.
Class: |
623/2.11 |
Current CPC
Class: |
A61F 2/2427 20130101;
Y10S 623/902 20130101 |
Class at
Publication: |
623/2.11 |
International
Class: |
A61F 2/24 20060101
A61F002/24 |
Claims
1. A method for replacing native valve function of a diseased
aortic valve in a patient, comprising: (a) receiving an artificial
heart valve assembly mounted about a first mounting position on a
catheter system; (b) guiding the artificial heart valve assembly
through the vasculature of the patient; (c) while the catheter
system having the artificial heart valve assembly mounted thereto
is in the patient's vasculature, mounting the artificial heart
valve assembly about a second mounting position on the catheter
system; (d) delivering the artificial heart valve assembly to the
region of the diseased aortic valve; (e) expanding the artificial
heart valve assembly in the region of the diseased aortic valve;
and (f) withdrawing the catheter system from the patient's
vasculature.
2. The method of claim 1, wherein the artificial heart valve
assembly is self-expandable.
3. The method of claim 1, wherein the artificial heart valve
assembly is balloon expandable.
4. The method of claim 1, wherein the artificial heart valve
assembly is delivered to and expanded in the native aortic valve
annulus.
5. The method of claim 4, wherein the native aortic valve is
excised before the artificial heart valve assembly is expanded in
the native aortic valve annulus.
6. The method of claim 1, wherein said expanding the artificial
heart valve assembly in the region of the diseased aortic valve
occurs while the patient's heart is beating.
7. The method of claim 1, wherein the artificial heart valve
assembly is a stented artificial heart valve assembly.
8. The method of claim 1, wherein the artificial heart valve
assembly comprises a biological valve.
9. The method of claim 1, wherein the artificial heart valve
assembly mounted about the first mounting position is press fit or
friction fit about the first mounting position.
10. The method of claim 1, wherein said mounting the artificial
heart valve assembly about the second mounting position includes
press fitting or friction fitting the artificial heart valve
assembly about the second mounting position.
11. The method of claim 1, wherein said guiding the catheter system
through the vasculature of the patient includes guiding the
catheter system through a peripheral artery of the patient.
12. A method for replacing native valve function of a diseased
aortic valve in a patient, comprising: (a) guiding a catheter
system having a balloon through the vasculature of the patient; (b)
guiding an artificial heart valve assembly through the vasculature
of the patient; (c) while the catheter system is in the patient's
vasculature, positioning the artificial heart valve assembly about
the balloon of the catheter system; (d) delivering the artificial
heart valve assembly to the region of the diseased aortic valve;
(e) expanding the artificial heart valve assembly in the region of
the diseased aortic valve; and (f) withdrawing the catheter system
from the patient's vasculature.
13. The method of claim 12, wherein the artificial heart valve
assembly was not previously coupled to the catheter system prior to
said positioning.
14. The method of claim 12, wherein the artificial heart valve
assembly is self-expandable.
15. The method of claim 12, wherein the artificial heart valve
assembly is balloon expandable.
16. The method of claim 12, wherein the artificial heart valve
assembly is delivered to and expanded in the native aortic valve
annulus.
17. The method of claim 16, wherein the native aortic valve is
excised before the artificial heart valve assembly is expanded in
the native aortic valve annulus.
18. The method of claim 12, wherein said expanding the artificial
heart valve assembly the region of the diseased aortic valve occurs
while the patient's heart is beating.
19. The method of claim 12, wherein the artificial heart valve
assembly is a stented artificial heart valve assembly.
20. The method of claim 12, wherein the artificial heart valve
assembly comprises a biological valve.
21. The method of claim 12, wherein said guiding the catheter
system through the vasculature of the patient includes guiding the
catheter system through a peripheral artery of the patient.
22. The method of claim 12, wherein said guiding the artificial
heart valve assembly through the vasculature of the patient
includes guiding the artificial heart valve assembly through a
peripheral artery of the patient.
23. A system for replacing native valve function of a diseased
aortic valve in a patient, comprising: (a) an artificial heart
valve assembly; (b) a first mount capable of engaging said
artificial heart valve assembly while said artificial heart valve
assembly is advanced through the patient's vasculature; (c) a
second mount capable of engaging said artificial heart valve
assembly while said artificial heart valve assembly is proximate to
the region of the diseased aortic valve; (d) a catheter system
capable of being manipulated a first time to transfer said
artificial heart valve assembly from said first mount to said
second mount, and capable of being manipulated a second time to
expand said artificial heart valve assembly into the region of the
diseased aortic valve.
24. The system of claim 23, wherein said first mount is not coupled
to said catheter system.
25. The system of claim 23, wherein said artificial heart valve
assembly is self-expandable.
26. The system of claim 23, wherein said artificial heart valve
assembly is balloon expandable.
27. The system of claim 23, wherein said second mount is a
balloon.
28. The system of claim 23, wherein the artificial heart valve
assembly is expanded into the native aortic valve annulus.
29. The system of claim 28, wherein the native aortic valve has
been excised.
30. The system of claim 23, wherein said catheter system is capable
of being manipulated to transfer and expand said artificial heart
valve assembly while the patient's heart is beating.
31. The system of claim 23, wherein said artificial heart valve
assembly is a stented artificial heart valve assembly.
32. The system of claim 23, wherein said artificial heart valve
assembly comprises a biological valve.
33. The system of claim 23, wherein said first mount is capable of
engaging said artificial heart valve assembly via a press fitting
or a friction fitting.
34. The system of claim 23, wherein said first mount is capable of
engaging said artificial heart valve assembly while said artificial
heart valve assembly is advanced through a peripheral artery of the
patient.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation of U.S. patent
application Ser. No. 10/895,272, filed Jul. 20, 2004, which is a
continuation of U.S. patent application Ser. No. 09/896,259, filed
Jun. 29, 2001, now U.S. Pat. No. 6,769,434, which claims priority
to U.S. Provisional Pat. App. No. 60/215,245, filed Jun. 30,
2000.
BACKGROUND OF THE INVENTION
[0002] Of all valvular heart lesions, aortic stenosis carries the
worst prognosis. Within one year of diagnosis, approximately half
of all patients with critical aortic stenosis have died, and by
three years, this figure rises to approximately 80%. Currently, the
most prominent and effective treatment for patients with aortic
stenosis is aortic valve replacement via open heart surgery.
Unfortunately, this procedure is a substantial and invasive
undertaking for the patient.
[0003] While there have been significant advances in heart valve
technology over the past 30 years, there has been little progress
in the development of safer and less invasive valve delivery
systems. Aortic valve replacement currently requires a sternotomy
or thoracotomy, use of cardiopulmonary bypass to arrest the heart
and lungs, and a large incision on the aorta. The native valve is
resected through this incision and then a prosthetic valve is
sutured to the inner surface of the aorta with a multitude of
sutures passing only partly into the wall of the aorta. Given the
current invasiveness of this procedure and the requirement to
utilize cardiopulmonary bypass, aortic valve replacement surgery is
associated with a high risk of morbidity and mortality. This is
especially true in elderly patients, and in those patients who
require concomitant coronary artery bypass grafting. Even when a
good surgical result is achieved, virtually all patients require
approximately 6 weeks to several months to fully recover from the
procedure. In order to decrease these associated risks of aortic
valve surgery, many have pursued novel approaches and
technologies.
[0004] Less invasive approaches to aortic valve surgery have
generally followed two paths.
[0005] In the 1980's, there was a flurry of interest in
percutaneous balloon valvotomy. In this procedure, a cardiologist
introduced a catheter through the femoral artery to dilate the
patient's aortic valve, thereby relieving the stenosis. Using the
technology available at that time, success was limited: the valve
area was increased only minimally, and nearly all patients had
restenosis within one year.
[0006] More recently, surgeons have approached the aortic valve via
smaller chest wall incisions. However, these approaches still
require cardiopulmonary bypass and cardiac arrest, which themselves
entail significant morbidity and a prolonged post-operative
recovery.
[0007] The ideal minimally invasive approach to the treatment of
aortic valve disease requires aortic valve replacement without
cardiopulmonary bypass and without cardiac arrest. Such an approach
would greatly reduce patient morbidity and mortality and hasten
recovery. Unfortunately, although there has been great progress in
the treatment of coronary artery disease without cardiopulmonary
bypass (e.g., angioplasty, with or without stenting, and "off-pump"
coronary artery bypass grafting), similar advances have not yet
been realized in heart valve surgery. With an aging population and
improved access to advanced diagnostic testing, the incidence and
accurate diagnosis of aortic stenosis will continue to increase.
The development of a system for "off-pump" aortic valve replacement
would be of significant benefit to this increasing patient
population.
[0008] There are three important challenges to replacing a diseased
aortic valve without cardiopulmonary bypass.
[0009] The first challenge is to remove the diseased valve without
causing stroke or other ischemic events that might result from the
liberation of particulate material while removing the diseased
valve.
[0010] The second challenge is to prevent cardiac failure during
removal of the diseased valve. In this respect it must be
appreciated that the aortic valve continues to serve a critical
function even when it is diseased. However, as the diseased valve
is removed, it becomes acutely and severely incompetent, causing
the patient to develop heart failure which results in death unless
the function of the valve is taken over by another means.
[0011] The third challenge is placing a prosthetic valve into the
vascular system and affixing it to the wall of the aorta. More
particularly, during cardiac rhythm, the aortic and arterial
pressures are substantially greater than atmospheric pressure.
Therefore, any sizable incision made to the aorta in order to
insert a standard valve prosthesis into the arterial system creates
the potential for uncontrollable bleeding from the incision site.
Furthermore, even if bleeding is successfully controlled, pressures
within the aorta may result in weakening of the aorta caused by
aortic wall dissection. In addition, large incisions on the aorta
also increase the potential for liberating plaque from the aortic
wall that can lead to embolic complications.
[0012] For these reasons, prior art valve prostheses potentially
suitable for off-pump implantation have relied upon relatively
flimsy expandable structures to support and secure the valve within
the aorta. More particularly, these prosthetic valves are
constructed so that they can be compressed to a relatively small
dimension suitable for insertion into the arterial system, advanced
to the site of the aortic valve, and then expanded against the
aortic wall. Unfortunately, however, none of these relatively
flimsy valve prostheses have proven adequate to endure the
repetitive stresses undergone by the aortic valve over the ten to
twenty years typically required.
[0013] In addition to the foregoing, the precise placement of such
expandable prosthetic valves in the correct sub-coronary position
can be extremely challenging, particularly in view of the high
pressure, pulsatile blood flow passing through the aorta.
Furthermore, expandable prosthetic valves would typically be
positioned from a remote artery, which would reduce the ability to
precisely control the placement and positioning of the device and
therefore would increases the risk of obstructing the coronary
arteries. The expandable prosthetic valves are held on the ends of
elongate, flexible catheters that are threaded into the aorta,
around the aortic arch and then expanded. The pulsatile flow during
cardiac rhythm induces a to-and-fro motion of the valve prosthesis
relative to the aorta that makes the timing of valve expansion
critical for proper placement of the expandable prosthetic valve
and hence the survival of the patient.
[0014] Finally, many of the challenges discussed in the foregoing
section pertaining to aortic valve replacement are also relevant to
other procedures in the aortic root such as aortic valve resection,
aortic valve decalcification, stent grafting for aortic
dissections, etc.
SUMMARY OF THE INVENTION
[0015] It is, therefore, one object of the present invention to
enable the passage of a device from the left atrium, through the
left ventricle, and into the arterial system.
[0016] Further, another object of the present invention is to
enable the implantation of a device in the arterial system without
cardiopulmonary bypass.
[0017] Further, another object of the present invention is to
enable the implantation of a prosthetic valve in the arterial
system without cardiopulmonary bypass.
[0018] Another object of the present invention is to allow the
insertion of such a valve while minimizing the risks to the patient
posed by large arterial incisions.
[0019] And another object of the present invention is to simplify
the precise placement of such a valve.
[0020] Further, another object of the present invention is to
enable the implantation of a device other than a valve, such as but
not limited to a valve resection tool, a decalcifying tool, an
aortic valve repair tool, or a stented aortic graft, in the
arterial system without cardiopulmonary bypass.
[0021] Another object of the present invention is to allow the
insertion of a device other than a valve, such as but not limited
to a valve resection tool, a decalcifying tool, an aortic valve
repair tool, or a stented aortic graft, while minimizing the risks
to the patient posed by large arterial incisions.
[0022] And another object of the present invention is to simplify
the precise placement of a device other than a valve, such as but
not limited to a valve resection tool, a decalcifying tool, an
aortic valve repair tool, or a stented aortic graft.
[0023] The present invention relates to a method and apparatus for
positioning a device in the arterial system. More specifically, the
present invention relates to a method and apparatus for positioning
an aortic valve prosthesis in the aorta or aortic outflow tract,
with or without cardiopulmonary bypass.
[0024] One aspect of the present invention is a method for
deploying an aortic valve prosthesis. This valve prosthesis may
include any of the known aortic valves including, but not limited
to, stented and unstented bioprosthetic valves, stented mechanical
valves, and expandable or self-expanding valves, whether biological
or artificial.
[0025] In one aspect of the invention, there is provided a method
of inserting a prosthesis or device from a lower pressure region
into a higher pressure region of the cardiovascular system
comprising the steps of: making an opening in a wall of a lower
pressure region of the cardiovascular system; advancing the
prosthesis or device through the opening and into the lower
pressure region; and advancing the prosthesis or device through a
natural barrier between the lower pressure region and the higher
pressure region.
[0026] In another aspect of the invention, there is provided a
method of inserting a prosthesis or device into a vessel within the
arterial system comprising the steps of: making an opening in a
wall of a low pressure region of the heart; advancing the
prosthesis or device through the opening and into the low pressure
region; advancing the prosthesis or device through a natural
barrier between the low pressure region and the left ventricle; and
advancing the prosthesis or device from the left ventricle into the
arterial system and the vessel.
[0027] And in another aspect of the invention, there is provided a
method of inserting a prosthesis or device into a vessel within the
arterial system comprising the steps of: making an opening in a
wall of the left atrium; advancing the prosthesis or device through
the opening and into the left atrium; advancing the prosthesis or
device through the mitral valve and into the left ventricle; and
advancing the prosthesis or device from the left ventricle into the
arterial system and the vessel.
[0028] And in another aspect of the present invention, there is
provided a method for positioning a device in the arterial system
comprising the steps of: making a first opening leading to the left
atrium; passing a valve prosthesis through the first opening and
into a cardiac chamber of the left side of the heart using a first
manipulation instrument; making a second opening in the arterial
system and advancing one end of a second manipulation instrument
through the second opening and into the aforementioned cardiac
chamber; securing the second manipulation instrument to the valve
prosthesis; and then using the second manipulation instrument to
retract at least some portion of the valve prosthesis out of the
aforementioned cardiac chamber.
[0029] An alternative method for positioning a device in the
arterial system comprises the steps of: making an opening leading
to the left atrium; passing a valve prosthesis through the opening
and into a cardiac chamber of the left side of the heart using an
articulating manipulation instrument; using the articulating
manipulation instrument to guide the valve prosthesis into the
arterial cardiac chamber; releasing the valve prosthesis into a
desired position: and then retracting at least a portion of the
articulating manipulation instrument out of the aforementioned
cardiac chamber and left atrium.
[0030] The pressure of blood flowing through the left atrium is
very low, peaking at a few inches of water during the cardiac
cycle. This pressure is a small fraction of that found within the
arterial system and thus permits insertion of a conventional valve
prosthesis through a relatively large opening formed in the wall of
the left atrium without the risk of uncontrollable bleeding. In
this respect it will be appreciated that various methods are known
to those skilled in the art for controlling bleeding from an
incision into the left atrium. The left atrium also rarely suffers
from atherosclerotic plaque formation or calcification, thus
minimizing the risk of embolic debris during such incision.
[0031] Another aspect of the present invention is the use of a
prosthesis holding apparatus for releasably holding the valve
prosthesis during manipulation to its implant site. The prosthesis
holding apparatus may be secured to the prosthetic valve at any
suitable location(s) through the use of any of a variety of
approaches including, but not limited to, suture loops, barbs,
hooks, grasping jaws, opposing magnetic poles, friction fits and
the like. The prosthesis holding apparatus is configured to
provides first and second manipulation mounts for engagement by the
aforementioned first and second manipulation instruments,
respectively, whereby the prosthetic valve can be delivered to its
implant site. This construction is highly advantageous in that it
permits the valve prosthesis to be passed easily and reliably from
the first manipulation instrument to the second manipulation
instrument within the vascular system.
[0032] In an alternative preferred embodiment, the prosthetic
holding apparatus is attached on the ventricular side of the
prosthesis. The aforementioned first manipulation instrument would
articulate at or near the prosthetic valve to facilitate
manipulation of the prosthesis holding apparatus (and hence the
prosthesis itself) through the smallest possible incision site,
then through the left atrium, the mitral valve and within the heart
to align and position the prosthesis within the aortic annulus or
left ventricular outflow track. In this alternative embodiment,
there is no need for the aforementioned second manipulation
instrument or the second manipulation mount.
[0033] In addition, if the prosthesis holding apparatus is attached
on the aortic side of the prosthesis, the manipulation instrument
may articulate and may be introduced into the arterial system,
brought across the mitral valve into the left atrium, out the left
atrium to pick up the prosthesis holding apparatus (and hence the
prosthesis) and then retracted back to position the prosthesis
directly into the aortic annulus without the need for another
manipulation instrument.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] These and other objects and features of the present
invention will be more fully disclosed or rendered obvious by the
following detailed description of the preferred embodiments of the
invention, which is to be considered together with the accompanying
drawings wherein like numbers refer to like elements and further
wherein:
[0035] FIG. 1 is a schematic side view showing the introduction of
a valve prosthesis and prosthesis holding apparatus into the left
atrium of the heart, through an atriotomy, using a first
manipulation instrument;
[0036] FIG. 2 is a schematic side view showing passage of the
apparatus of FIG. 1 from the left atrium, through the mitral valve,
and into the left ventricle;
[0037] FIG. 3 is a schematic side view showing the introduction of
a second manipulation instrument into the left ventricle through an
arteriotomy into the arterial system;
[0038] FIG. 4 is a schematic side view showing the second
manipulation instrument being attached to the prosthesis holding
apparatus while the first manipulation instrument remains secured
to the prosthesis holding apparatus;
[0039] FIG. 5 is a schematic side view similar to that of FIG. 4,
except showing the first manipulation instrument being removed from
the surgical site while the second manipulation instrument remains
secured to the prosthesis holding apparatus;
[0040] FIG. 6 is a schematic side view showing the second
manipulation instrument positioning the prosthetic valve within the
aorta prior to fixation;
[0041] FIG. 7 is a schematic side view showing the prosthetic valve
secured to the tissues of the aorta following removal of the second
manipulation instrument and prosthesis holding apparatus;
[0042] FIGS. 8, 9 and 10 are enlarged schematic views showing a
preferred construction for the valve holding apparatus, and for the
attachment to, and detachment from, the prosthetic valve; and
[0043] FIG. 11 is a schematic view showing a guide for guiding the
second manipulation instrument relative to the first manipulation
instrument such that the second manipulation instrument will be
aimed directly at the second manipulation mount when the first
manipulation mount is secured to the first manipulation
instrument.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0044] The present invention can be used to implant a variety of
prostheses into the arterial system or left side of the heart. The
prosthesis used in the preferred embodiment is an aortic valve
prosthesis. Alternatively, the prosthesis may comprise, but is not
limited to, a cylindrical arterial stent, an arterial prosthesis or
graft, a ventricular assist device, a device for the treatment of
heart failure such as an intraventricular counterpulsation balloon,
chordae tendinae prostheses, arterial filters suitable for acute or
chronic filtration of emboli from the blood stream, arterial
occlusion devices and the like.
[0045] For clarity of illustration, the present invention will
hereinafter be discussed in the context of implanting an aortic
valve prosthesis.
[0046] It should also be appreciated that the present invention may
be practiced either "on-pump" or "off-pump". In other words, the
present invention may be performed either with or without the
support of cardiopulmonary bypass. The present invention also may
be performed either with or without cardiac arrest.
[0047] Looking now at FIG. 1, there is shown an exemplary
embodiment of the present invention. A prothesis holding apparatus
100 is secured to a prosthetic valve 200 so as to form a temporary
prosthetic assembly 300. A first manipulation instrument 400 is
secured to a first manipulation mount 105 formed on prosthesis
holding apparatus 100, whereby temporary prosthetic assembly 300
may be moved about by first manipulation instrument 400. Temporary
prosthetic assembly 300 has been positioned in left atrium 5 by
passing first manipulation instrument 400 through atriotomy 10.
Alternatively, the temporary prosthetic assembly 300 could be
passed into the left atrium 5, using first manipulation instrument
400, through any of the pulmonary veins 15. And in another form of
the invention, temporary prosthesis assembly 300 could be passed
into the left atrium by first passing the assembly into the right
atrium via an atriotomy, and then into the left atrium through an
incision made in the interatrial septum.
[0048] Prosthetic valve 200 is preferably a conventional mechanical
aortic valve of the sort well known in the art, although other
forms of valve prostheses may also be used.
[0049] In one preferred form of the invention, first manipulation
instrument 400 functions by virtue of the relative motion of an
outer cannula 405 relative to an inner grasper 410. More
particularly, inner grasper 410 has an elastically deformable
distal gripper 415 which is open when the gripper is outside of
outer cannula 405. However, when deformable gripper 415 is pulled
at least partially into or against outer cannula 405, gripper 415
is elastically deformed into a closed position, whereby it may grip
an object, e.g., first manipulation mount 105 formed on prosthesis
holding apparatus 100. First manipulation instrument 400 is shown
in FIG. 1 in its closed position, wherein deformable gripper 415 is
closed about first manipulation mount 105, such that prosthesis
holding apparatus 100, and hence the entire temporary prosthetic
assembly 300, is held secured to the distal end of first
manipulation instrument 400.
[0050] The specific embodiment of first manipulation instrument 400
shown in FIG. 1 is presented as an illustrative example only, and
is not intended to limit the scope of the present invention. Many
other arrangements may be used for releasably gripping first
manipulation mount 105 formed on prosthesis holding apparatus 100.
Furthermore, first manipulation mount 105 may itself have many
potential shapes and properties to enable releasable attachment to
first manipulation instrument 400. Other possible configurations
for releasably securing first manipulation mount 105 to first
manipulation instrument 400 include, but are not limited to,
opposing magnet poles in the mount and instrument, adhesives, a
press fit between mount and instrument, threaded couplings, suture
loops, a balloon or balloons expanded within a mating cavity,
collapsible barbs, etc. For the purposes of the present invention,
the important point is that some arrangement be provided for
releasably securing the prosthesis holding apparatus (and hence the
prosthetic valve) to a manipulation instrument.
[0051] Still looking now at FIG. 1, first manipulation instrument
400 is shown as having a long axis that extends outside of the
heart, with first manipulation instrument 400 being straight along
that axis. However, it should also be appreciated that first
manipulation instrument 400 may, alternatively, be formed with a
curve at one or more location along this length. Furthermore, first
manipulation instrument 400 may be constructed so as to allow
articulation at the distal end, the proximal end, or both, or at
any point therebetween. In addition, first manipulation instrument
400 may be formed either entirely rigid or substantially flexible,
along all or part of its length.
[0052] First manipulation instrument 400 is also shown as having a
relatively small dimension perpendicular to its long axis. This
configuration allows atriotomy 10 to be reduced in size after the
passage of temporary prosthetic assembly 300 into left atrium 5.
This perpendicular dimension may be constant or varied along the
long axis of first manipulation instrument 400.
[0053] The specific embodiment of the prosthesis holding apparatus
100 shown in FIG. 1 is presented as an illustrative example only,
and is not intended to limit the scope of the present invention.
Many other arrangements may be used for releasably gripping
prosthetic valve 200 and for providing first manipulation mount
105, as well as providing a second manipulation mount 110 that will
be discussed below. In FIG. 1, first manipulation mount 105 and
second manipulation mount 110 are shown as spherical additions to
struts 115 extending away from prosthetic valve 200. These spheres
are intended to fit, respectively, within the deformable gripper
415 of first installation instrument 400 and the deformable gripper
515 of a second installation instrument 500 (discussed below).
First manipulation mount 105 and/or second manipulation mount 110
could, alternatively, be indentations within a portion of male or
female threaded extensions from, magnetized surfaces of, slots or
holes in or through, prosthesis holding apparatus 100, etc.
Furthermore, first manipulation mount 105 and/or second
manipulation mount 110 could be portions of the struts 115
extending away from prosthetic valve 200, where those portions may
be either reduced or enlarged in dimension relative to neighboring
portions of the struts. Many other constructions may also be used
to form first manipulation mount 105 and second manipulation mount
110. For the purposes of the present invention, the important point
is that some arrangement be provided for releasably securing the
prosthesis holding apparatus (and hence the prosthetic valve) to
manipulation instruments.
[0054] Still looking now at FIG. 1, it will be appreciated that the
native aortic valve has been removed. Removal of the native aortic
valve is not a necessary element of the present invention, but may
be incorporated into the preferred method. Removal of the native
aortic valve may be accomplished either before or after passage of
the temporary prosthetic assembly 300 into left atrium 5.
[0055] When the methods and devices of the present invention are
employed during an off-pump valve replacement procedure, it may be
beneficial to provide temporary valves and/or filters in the
arterial system, downstream of the site of the native aortic valve.
Thus, for example, in FIG. 2 there is shown a temporary valve 600
which may be used to support cardiac function during and following
removal of the diseased cardiac valve. Temporary valve 600 is shown
positioned in aorta 20. Alternatively, temporary valve 600 may be
positioned in the aortic arch or the descending aorta. In addition,
temporary valve 600 may incorporate a filter therein to mitigate
the risks of embolic complications. Alternatively, a separate
filter may be employed within the aorta and/or the branch arteries
extending therefrom.
[0056] FIG. 2 shows first manipulation instrument 400 being used to
manipulate temporary prosthetic assembly 300 (and hence prosthetic
valve 200) into left ventricle 25 through mitral valve 30. After
temporary prosthetic assembly 300 has passed into left ventrical
25, the first manipulation instrument 400 will continue to traverse
mitral valve 30; however, the reduced perpendicular cross-section
of first manipulation instrument 400 will cause only minimal
disruption of the function of mitral valve 30.
[0057] FIG. 3 shows the insertion of a second manipulation
instrument 500 through the arterial system and into left ventricle
25. Second manipulation instrument 500 is shown being inserted
through an incision 35 on aorta 20. Alternatively, second
manipulation instrument 500 could be inserted into a central or
peripheral artery and than advanced into left ventricle 25. Aortic
incision 35 is small relative to the atriotomy 10 formed in left
atrium 5.
[0058] Bleeding through incision 35 may be readily controlled
through a variety of means. These include, but are not limited to,
employing a valved or un-valved arterial cannula, a purse-string
suture placed around incision 35 and then pulled tight about second
manipulation instrument 500, a side-arm graft sewn to aorta 20 that
may be constricted about a region of second manipulation instrument
500, the use of a tight fit between a portion of second
manipulation instrument 500 and aortic incision 35, etc.
[0059] Second manipulation instrument 500 is shown in FIG. 3 as
being of the same form and function of first manipulation
instrument 400. Again, outer cannula 505 fits around inner grasper
510, and the relative motion between grasper 510 and cannula 505
can be used to deform gripper 515 between open and closed
positions. Alternatively, second manipulation instrument 500 may
have any of the variety of other forms and functions described
above with respect to first manipulation instrument 400.
Furthermore, second manipulation instrument 500 is preferably of a
smaller dimension perpendicular to its long axis than first
manipulation instrument 400 so as to reduce the risks posed by
arteriotomy 35.
[0060] FIG. 4 shows second manipulation instrument 500 being
secured to the second manipulation mount 110 formed on prosthesis
holding apparatus 100. This is done while first manipulation
instrument 400 is secured to first manipulation mount 105 formed on
prosthesis holding apparatus 100, in order that temporary
prosthetic assembly 300 will be under control at all times during
the "hand-off" between first manipulation instrument 400 and second
manipulation instrument 500.
[0061] It should be appreciated that the orientation of second
manipulation mount 110 is preferably such as to enable the long
axis of second manipulation instrument 500 to be substantially
perpendicular to the flow area of prosthetic valve 200. This
arrangement is particularly helpful when guiding prosthetic valve
200 into its final position within aorta 20 as shown hereafter in
FIGS. 6 and 7.
[0062] The use of two separate manipulation instruments, and the
method of passing valve prosthesis 200 from one to the other,
avoids the complex manipulations of valve prosthesis 200 that would
be required to position valve 200 within aorta 20 using only a
single manipulation instrument introduced through the left atrium.
In this respect it should be appreciated that such a "single
manipulation instrument" technique has been found to be possible,
however, and is best facilitated by using a manipulation instrument
capable of bending or articulating at or near the site of its
attachment to valve holding apparatus 100. In this respect it has
been found that it can be particularly advantageous to provide a
manipulation instrument capable of bending or articulating within
about 4 cm or so of the point of attachment to valve holding
apparatus 100. It has also been found that it can be particularly
advantageous for such an articulating instrument to be able to
deflect its distal tip by an angle of between about 90 to 180
degrees from the long axis of the first manipulation instrument 400
shown in FIG. 4.
[0063] The angular offset of first manipulation mount 105 and
second manipulation mount 110 is preferably set to facilitate
passage of temporary prosthetic assembly 300 from left atrium 5 to
aorta 20 using two substantially straight manipulation instruments,
e.g., first manipulation instrument 400 and second manipulation
instrument 500. This angle is preferably approximately 45 degrees.
However, this angle may also be varied so as to optimize passage of
different valve designs or other prostheses using curved, straight
or articulating manipulation instruments from various access sites
into the left atrium and arterial system. This angle may be fixed
or variable on a given prosthesis holding apparatus 100.
[0064] Once second manipulation instrument 500 is safely secured to
second manipulation mount 110, first manipulation instrument 400
may be released from first manipulation mount 105 and removed from
left ventricle 5, as shown in FIG. 5. Alternatively, first
manipulation instrument 400 may remain secured to prosthesis
holding apparatus 100 or prosthetic valve 200 by a flexible tether
so as to facilitate re-attachment of first manipulation instrument
400 to valve holding apparatus 100 if necessary.
[0065] FIG. 6 shows temporary prosthesis assembly 300 being
positioned by second manipulation instrument 500 at a preferred
fixation site. This fixation site is preferably upstream of or
proximal to the coronary arteries, although this position is not a
restrictive requirement of the present invention.
[0066] FIG. 7 shows valve prosthesis 200 secured to the walls of
aorta 30 and removal of second manipulation instrument 500 and
prosthesis holding apparatus 100. In this respect it should be
appreciated that prosthesis holding apparatus 100 is preferably
wholly or partially flexible, or otherwise collapsible, so as to
allow the prosthesis holding apparatus 100 to be collapsed radially
and then withdrawn through arteriotomy 35 after prosthesis holding
apparatus 100 has been released from prosthetic valve 200.
Alternatively, prosthesis holding apparatus 100 may be removed from
the vascular system, either partially or entirely, through
atriotomy 10 by first manipulation instrument 400, by a tether
leading therefrom, or a separate instrument. Of course, in the
situation where prosthesis holding apparatus 100 is to be removed
via atriotomy 10, the prosthesis holding apparatus 100 should be
appropriately mounted to prosthetic valve 200, i.e., prosthesis
holding apparatus 100 should be positioned on the atriotomy side of
the valve.
[0067] In FIG. 7, valve prosthesis 200 is shown secured to aorta 30
using barbs or staples 700. Barbs or staples 700 may be a component
of, and/or deployed from, prosthesis holding apparatus 100, and/or
valve prosthesis 200, and/or a separate fixation device.
Alternatively, barbs or staples 700 may be deployed by a separate
instrument inserted through the outer surface of aorta 30, from a
remote site in the arterial system, through atriotomy 10 or through
some other incision into a cardiac chamber or great vessel.
[0068] Looking next at FIGS. 8-10, there is shown one preferred
configuration for prosthesis holding apparatus 100. More
particularly, prosthesis holding apparatus 100 comprises a base 120
having a longitudinal opening 123 (FIG. 9) therein for slidably
receiving a rod 125 therethrough. Base 120 also comprises a
plurality of side slots 130. Each side slot 130 has a strut 115
pivotally connected thereto. Slots 130 are constructed so that each
strut 115 can pivot freely between (i) the position shown in FIGS.
8 and 9, and (ii) the position shown in FIG. 10. A body 135 is
mounted on rod 125. A plurality of wire fingers 140 are secured to
body 135. Wire fingers 140 extend through holes 145 formed in base
120 and extend around the cuff 205 of prosthetic valve 200. Second
manipulation mount 110 is secured to the proximal end of rod 125.
First manipulation mount 105 is secured to one of the struts 115.
Alternatively, as noted above, first manipulation mount 105 may be
formed by a strut 115 itself, provided that first manipulation
instrument 400 is appropriately adapted to engage the strut 15
directly.
[0069] In use, prosthesis holding apparatus 100 is fit about valve
prosthesis 200 so that wire fingers 140 hold valve cuff 205 to
struts 115. Prosthesis holding apparatus 100 is then engaged by
first manipulation instrument 400, using first manipulation mount
105, and moved into and through right atrium 5, through mitral
valve 30 and into left ventricle 25. Then second manipulation tool
500, comprising outer cannula 505 and inner grasper 510 having the
deformable gripper 515, engages second manipulation mount 110. The
distal tip 520 of outer cannula 505 is placed against edge 150 of
base 120 and gripper 515 is drawn proximally within outer cannula
505 until deformable gripper 515 engages shoulder 525, whereupon
prosthesis holding apparatus 100 (and hence prosthetic valve 200)
will be mounted to second manipulation tool 500. Second
manipulation tool 500 is then used to maneuver temporary prosthetic
assembly 300 into position, whereupon the valve's cuff 205 is
secured to the side wall of the aorta, e.g., with barbs, staples,
suture, etc. Then prosthesis holding apparatus 100 is detached from
prosthetic valve 200 by pulling inner grasper 510 proximally
relative to outer cannula 505 so that wire fingers 140 are pulled
past valve cuff 205 (FIG. 9), whereby to free prosthesis holding
apparatus 100 from the prosthetic valve 200. Then second
manipulation instrument 500 is withdrawn out aorta 20 and
arteriotomy 35, with struts 115 folding inwardly (FIG. 10) so as to
pass through the arteriotomy. Struts 115 can be adapted to fold
inwardly through engagement with the walls of the arteriotomy 35
or, alternatively, additional means (such as springs, cams, etc.)
can be provided to fold struts 115 inwardly.
[0070] In practice, it has been found that it can sometimes be
difficult to locate second manipulation mount 110 with second
manipulation instrument 500 so as to "hand off' temporary
prosthesis assembly 300 from first manipulation instrument 400 to
second manipulation instrument 500. This can be particularly true
where the procedure is to be conducted "off-pump", i.e., without
stopping the heart. To this end, and looking now at FIG. 11, there
is shown a guide 800 for guiding second manipulation instrument 500
relative to first manipulation instrument 400 such that second
manipulation instrument 500 will be aimed directly at second
manipulation mount 110 when first manipulation mount 105 is secured
to first manipulation instrument 400. More particularly, guide 800
comprises a first passageway 805 for slidably receiving first
manipulation instrument 400, and a second passageway 810 for
slidably receiving second manipulation instrument 500. Passageways
805 and 810 are oriented so that second manipulation instrument 500
will be aimed directly at second manipulation mount 110 when
temporary prosthesis assembly 300 is held by first manipulation
instrument 400 engaging first manipulation mount 105.
[0071] In accordance with the present invention, it is also
possible to enter the left atrium other than through an exterior
wall of the left atrium. Thus, for example, it is possible to
introduce the prosthetic valve through an opening in an exterior
wall of the right atrium, pass the prosthetic valve through an
incision in the interatrial septum and across to the left atrium,
and then advance the prosthetic valve to its implantation site via
the mitral valve and the left ventricle.
[0072] As noted above, the manipulation instrument(s) do not need
to take the form of the installation instrument 400 or 500. It is
also possible to deliver the prosthetic valve to its implant site
using a guidewire and a pusher tool riding on the guidewire.
[0073] Thus, for example, in an alternative preferred embodiment, a
wire, a catheter, a tube or any other filament can be placed from
the left atrium, through the ventricle and into the arterial
system, over (or through) which a prosthesis or device can be
advanced (pushed or pulled). As an example, a catheter with a
balloon can be placed through an incision in the left atrial wall.
The balloon can be inflated and this catheter can then be "floated"
along the flow of blood across the mitral valve, into the left
ventricle, and out into the arterial system. At that point the
catheter can be grasped by an instrument placed through a small
incision in the aorta or passed into the aorta by means of a remote
vessel such as the femoral artery. At this point, the prosthesis or
device can be mounted onto the catheter and either be pushed (or
pulled) over the catheter into position. This procedure can be
similarly performed by the use of a wire or other filament
structure. Also, a tube could be employed, with the prosthesis or
device being advanced within the tube.
* * * * *