U.S. patent application number 10/714462 was filed with the patent office on 2004-05-27 for method and device for treatment of mitral insufficiency.
Invention is credited to Berger, Erwin, Kimblad, Per Ola, Schwager, Michael, Solem, Jan Otto.
Application Number | 20040102840 10/714462 |
Document ID | / |
Family ID | 25105151 |
Filed Date | 2004-05-27 |
United States Patent
Application |
20040102840 |
Kind Code |
A1 |
Solem, Jan Otto ; et
al. |
May 27, 2004 |
Method and device for treatment of mitral insufficiency
Abstract
A device for treatment of mitral annulus dilatation comprises an
elongate body having two states. IN a first of these states the
elongate body is insertable into the coronary sinus and has a shape
adapting to the shape of the coronary sinus. When positioned in the
coronary sinus, the elongate body is transferable to the second
state assuming a reduced radius of curvature, whereby the radius of
curvature of the coronary sinus and the radius of curvature as well
as the circumference of the mitral annulus is reduced.
Inventors: |
Solem, Jan Otto; (Stetten,
CH) ; Kimblad, Per Ola; (Lund, SE) ; Berger,
Erwin; (Stettfurt, CH) ; Schwager, Michael;
(Winterthur, CH) |
Correspondence
Address: |
CHRISTIE, PARKER & HALE, LLP
350 WEST COLORADO BOULEVARD
SUITE 500
PASADENA
CA
91105
US
|
Family ID: |
25105151 |
Appl. No.: |
10/714462 |
Filed: |
November 13, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10714462 |
Nov 13, 2003 |
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09775677 |
Feb 5, 2001 |
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09775677 |
Feb 5, 2001 |
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09345475 |
Jun 30, 1999 |
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6210432 |
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Current U.S.
Class: |
623/2.11 ;
623/2.36 |
Current CPC
Class: |
A61F 2/90 20130101; A61F
2/2451 20130101; A61F 2002/075 20130101; A61F 2/88 20130101; A61F
2230/0078 20130101; A61F 2220/0008 20130101; A61F 2/91
20130101 |
Class at
Publication: |
623/002.11 ;
623/002.36 |
International
Class: |
A61F 002/24 |
Claims
What is claimed is:
1. An assembly for effecting the condition of a mitral valve
annulus of a heart comprising: a guide wire configured to be
advanced to the coronary sinus of the heart; and a mitral valve
annulus device configured to be received on the guide wire and
advanced into the coronary sinus of the heart on the guide wire and
that reshapes the mitral valve annulus when in the coronary sinus
of the heart.
2. The assembly of claim 1 wherein the device is configured to be
slidingly received on the guide wire.
3. The assembly of claim 1 wherein the mitral valve annulus device
has opposed ends and includes a guide wire engaging structure at at
least one of the opposed ends.
4. The assembly of claim 3 wherein the guide wire engaging
structure includes a bore dimensioned to permit the guide wire to
pass therethrough.
5. The assembly of claim 4 wherein the device further includes a
guide wire confining channel extending between the opposed
ends.
6. The assembly of claim 4 wherein the bore of the guide wire
engaging structure is cylindrical in configuration.
7. The assembly of claim 6 wherein the device further includes a
guide wire confining channel extending between the opposed ends and
aligned with the bore.
8. The assembly of claim 1 wherein the guide wire is formed of a
material visible under X ray.
9. The assembly of claim 1 wherein at least a portion of the device
is visible under X ray.
10. The assembly of claim 1 wherein the device is visible under X
ray.
11. The assembly of claim 1 further including an elongated
introducer configured to be received on the guide wire proximal to
the device.
12. The assembly of claim 11 wherein the introducer is configured
to be slidingly received on the guide wire.
13. The assembly of claim 11 wherein the assembly further includes
a releasable locking mechanism configured to releasably lock the
device to the introducer.
14. The assembly of claim 11 further including a guide tube having
an inner lumen dimensioned for receiving the guide wire and the
device and introducer when the device and introducer are received
on the guide wire.
15. A method of deploying a mitral valve annulus constricting
device within the coronary sinus of a heart, the method including
the steps of: A. providing an elongated guide wire having a cross
sectional dimension; B. advancing the guide wire to the coronary
sinus of the heart; C. providing a guide tube having an inner
lumen, the inner lumen having a cross sectional dimension greater
than the cross sectional dimension of the guide wire; D. advancing
the guide tube to the coronary sinus of the heart on the guide wire
with the guide wire within the inner lumen of the guide tube; E.
providing a mitral valve annulus device configured to be received
on the guide wire and within the inner lumen of the guide tube, the
device including a proximal end; F. providing a flexible elongated
introducer configured to be received on the guide wire and within
the inner lumen of the guide tube, the introducer having a distal
end; G. placing the device onto the guide wire; H. placing the
introducer onto the guide wire; I. engaging the introducer with the
device; J. pushing the device with the introducer in a distal
direction along the guide wire and within the guide tube until the
device is at least partially encircling the mitral valve within the
coronary sinus of the heart; and K. withdrawing the introducer and
the guide tube from the heart.
16. The method of claim 15 wherein the engaging step includes the
step I(1) of releasably locking the device to the introducer.
17. The method of claim 16 including the further step J(1) of
releasing the device from the introducer prior to withdrawing the
introducer.
18. A method of deploying a mitral valve annulus reshaping device
within the coronary sinus of a heart, the method including the
steps of: advancing a guide wire to the coronary sinus of the
heart; advancing the elongated mitral valve annulus reshaping
device on the guide wire and into the coronary sinus into a
position such that the device at least partially encircles the
mitral valve of the heart.
19. The method of claim 18 wherein the advancing step further
includes the steps of mounting an elongated flexible introducer
onto the guide wire, engaging the introducer with the device, and
pushing the device distally into the coronary sinus with the
introducer.
20. The method of claim 19 including the further step of
withdrawing the introducer after deploying the device.
21. The method of claim 20 wherein the engaging step includes
releasably locking the device to the introducer.
22. The method of claim 21 including the further step of releasing
the device from the introducer prior to withdrawing the
introducer.
23. The method of claim 19 including the further steps of:
providing an elongated flexible guide tube having an inner lumen,
the inner lumen having a cross sectional dimension greater than the
cross sectional dimension of the guide wire; advancing the guide
tube to the coronary sinus of the heart over the guide wire with
the guide wire within the inner lumen of the guide tube; and
wherein the pushing step includes pushing the device along the
guide wire and within the guide tube.
24. The method of claim 23 wherein the engaging step includes
releasably locking the device to the introducer.
25. The method of claim 24 including the further steps of releasing
the device from the introducer and withdrawing the introducer and
the guide tube after deploying the device.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of U.S. patent
application Ser. No. 09/345,475 that was filed on Jun. 30,
1999.
BACKGROUND OF INVENTION
[0002] 1. Technical Field of the Invention
[0003] The present invention generally relates to a device and a
method for treatment of mitral insufficiency and, more
specifically, for treatment of dilatation of the mitral
annulus.
[0004] 2. Description of the Prior Art
[0005] Mitral insufficiency can result from several causes, such as
ischemic disease, degenerative disease of the mitral apparatus,
rheumatic fever, endocarditis, congenital heart disease and
cardiomyopathy. The four major structural components of the mitral
valve are the annulus, the two leaflets, the chordae and the
papillary muscles. Any one or all of these in different
combinations may be injured and create insufficiency. Annular
dilatation is a major component in the pathology of mitral
insufficiency regardless of cause. Moreover, many patients have a
mitral insufficiency primarily or only due to posterior annular
dilatation, since the annulus of the anterior leaflet does not
dilatate because it is anchored to the fibrous skeleton of the base
of the heart.
[0006] Studies of the natural history of mitral insufficiency have
found that totally asymptomatic patients with severe mitral
insufficiency usually progress to severe disability within five
years. At present the treatment consists of either mitral valve
replacements or repair, both methods requiring open heart surgery.
Replacement can be performed with either mechanical or biological
valves.
[0007] The mechanical valve carries the risk of thromboembolism and
requires anticoagulation, with all its potential hazards, whereas
biological prostheses suffer from limited durability. Another
hazard with replacement is the risk of endocarditis. These risks
and other valve related complications are greatly diminished with
valve repair.
[0008] Mitral valve repair is theoretically possible if an
essentially normal anterior leaflet is present. The basic four
techniques of repair include the use of an annuloplasty ring,
quadrangular segmental resection of diseased posterior leaflet,
shortening of elongated chordae, and transposition of posterior
leaflet chordae to the anterior leaflet.
[0009] Annuloplasty rings are needed to achieve a durable reduction
of the annular dilatation. All the common rings are sutured along
the posterior mitral leaflet adjacent to the mitral annulus in the
left atrium. The Duran ring encircles the valve completely, whereas
the others are open towards the anterior leaflet. The ring can
either be rigid, like the original Carpentier ring, or flexible but
non-elastic, like the Duran ring or the Cosgrove-Edwards ring.
[0010] Effective treatment of mitral insufficiency currently
requires open-heart surgery, by the use of total cardiopulmonary
by-pass, aortic cross-clamping and cardioplegic cardiac arrest.
[0011] To certain groups of patient, this is particular hazardous.
Elderly patients, patients with a poor left ventricular function,
renal disease, severe calcification of the aorta, previous cardiac
surgery or other concomitant diseases, would in particular most
likely benefit from a less invasive approach, even if repair is not
complete. The current trend towards less invasive coronary artery
surgery, without cardiopulmonary by-pass, as well as PTCA will also
call for a development of a less invasive method for repair of the
often concomitant mitral insufficiency.
SUMMARY OF THE INVENTION
[0012] Therefore, a first object of the present invention is to
provide a device and a method for treatment of mitral insufficiency
without the need for cardiopulmonary by-pass and without opening of
the chest and heart.
[0013] A second object of the invention is to provide reduction of
the mitral annulus using only catheter based technology.
[0014] According to the present invention, a device for treatment
of mitralis insufficiency comprises an elongate body having such
dimensions as to be insertable into the coronary sinus and having
two states, in a first state of which the elongate body has a shape
that is adaptable to the shape of the coronary sinus, and to the
second state of which the elongate body is transferable from the
said first state assuming a reduced radius of curvature, whereby
the radius of curvature of the coronary sinus is reduced as well as
the circumference of the mitral valve annulus, when the elongate
body is positioned in the coronary sinus. More precisely, the
elongate body comprises a distal stent section, a proximal stent
section and control wires for reducing the distance between the
distal and proximal stent sections.
[0015] Thus, means are provided for the transfer of the elongate
body to the second stat by shortening it from a larger radius of
curvature to a smaller radius of curvature.
[0016] The control wires may comprise a first wire and means for
guiding said first wire in a course extending two times between the
distal and proximal stent sections, when the distance therebetween
is at a maximum, and extending at least three times between the
distal and proximal stent sections, when the distance therebetween
is at a minimum.
[0017] To accomplish changes in the course, the guiding means
preferably comprises a first eyelet fixed to one of the distal and
proximal stent sections, a second eyelet fixed to the other of the
distal and proximal stent sections, and a third eyelet positioned
between the distal and proximal stent sections, said first wire
having a first end fixed to said one of the distal and proximal
stent section and extending therefrom via the third eyelet, the
first eyelet and the second eyelet back to the third eylet where a
second end of the first wire is fixed. By this structure the
maximum distance between the two stent sections will be about 1.5
times the minimum distance between the two stent sections.
[0018] A larger quotient may be obtained by extending the first
wire from the first eyelet at least once more via the third eyelet
and the first eyelet before finally extending the first wire via
the second eyelet back to the third eylet where the second end of
the first wire is fixed.
[0019] In order to reduce the distance beteween the distal stent
section and the proximal stent section, said first eyelet is
preferably fixed to the distal stent section and said control wires
comprise a second wire extending through the third eyelet and as a
double wire proximally therefrom out of the coronary sinus and out
of the human body. As an alternative to this second wire, a single
wire may be used having an end releasably fixed to the third eyelet
and extending as a single wire proximally therefrom out of the
coronary sinus and out of the human body. However, to be able to
also increase the distance between the distal stent section and the
proximal stent section, said control wires may comprise a third
wire extending through the third eyelet and as a double wire
distally to and through the first eyelet and then as a double wire
proximally therefrom out of the coronary sinus and out of the human
body.
[0020] Alternatively, the distance between the distal stent section
and the proximal stent section may be reduced by fixing the first
eyelet to the proximal stent section. Then, said control wires
should comprise a second wire extending through the third eyelet
and as a double wire distally to and through the first eyelet and
then as a double wire proximally therefrom out of the coronary
sinus and out of the human body. In order to be able to increase
the distance between the distal stent section and the proximal
stent section in this case, the control wires should comprise a
third wire extending through the third eyelet and as a double wire
proximally therefrom out of the coronary sinus and out of the human
body.
[0021] It should be noted that when the proximal and distal stent
sections have been fixed relative to the coronary sinus and the
distance between them thererafter has been finaly adjusted to a
desired value, the second and the third wires may in both the
described alternatives be withdrawn from the coronary sinus by
pulling one of their ends positioned outside of the coronary sinus
and outside of the human body.
[0022] In preferred embodiments of the device, a cover encloses the
wires in their courses between the distal and proximal stent
sections so as to eliminate the risk that the wires will injure the
coronary sinus by cutting into its internal surfaces.
[0023] The cover may comprise one or more plastic sheaths and may
also comprise one or more helical wires.
[0024] In an alternative embodiment, the device for treatment of
mitral annulus dilatation comprises an elongate body having such
dimensions as to be insertable into the coronary sinus and having
two states, in a first of which the elongate body has a shape that
is adaptable to the shape of the coronary sinus, and to the second
of which the elongate body is transferable from said first state
assuming a reduced radius of curvature, whereby the radius of
curvature of the coronary sinus is reduced as well as the
circumference of the mitral valve annulus, when the elongate body
is positioned in the coronary sinus, said elongate body comprising
at least one stent section at a distance from each end of the
elongate body, said stent section providing a reduction of its
length when expanded in situ in the coronary sinus, whereby the
elongate body is shortened and bent to a smaller radius of
curvature.
[0025] Preferably, the elongate body of this embodiment comprises a
proximal stent section, a distal stent section and a central stent
section, the distal and proximal stent sections being expandable
prior to the central stent section. Obviosly, this will result in a
reduction of the distance between the proximal and distal stent
sections. Further, the proximal and distal stent sections should be
expandable without substantial length reduction.
[0026] Thus, the present invention takes advantage of the position
of the coronary sinus being close to the mitral annulus. This makes
repair possible by the use of current catheter-guided
techniques.
[0027] The coronary veins drain blood from the myocardium to the
right atrium. The smaller veins drain blood directly into the
atrial cavity, and the larger veins accompany the major arteries
and run into the coronary sinus which substantially encircles the
mitral orifice and annulus. It runs in the posterior
atrioventricular groove, lying in the fatty tissue between the left
atrial wall and the ventricular myocardium, before draining into
the right atrium between the atrial septum and the post-Eustachian
sinus.
[0028] In an adult, the course of the coronary sinus may approach
within 5-15 mm of the medial attachment of the posterior leaflet of
the mitral valve. Preliminary measurements performed at autopsies
of adults of normal weight show similar results, with a distance of
5.3.+-.0.6 mm at the medial attachment and about 10 mm at the
lateral aspect of the posterior leaflet. The circumference of the
coronary sinus was 18.3.+-.2.9 mm at its ostium (giving a sinus
diameter of the septal aspect or the posterior leaflet of
5.8.+-.0.9 mm) and 9.7.+-.0.6 mm along the lateral aspect of the
posterior leaflet (corresponding to a sinus diameter of 3.1.+-.0.2
mm).
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] The invention will be better understood by the following
description of preferred embodiments referring to the appended
drawings, in which
[0030] FIG. 1 is a cross-sectional view of a part of a heart,
[0031] FIGS. 2 and 3 are schematic views of a first embodiment of a
device according to the present invention,
[0032] FIGS. 4-6 are schematic views illustrating an instrument,
which may be used when positioning the device shown in FIGS. 2 and
3 in the coronary sinus,
[0033] FIG. 7 is a partial, enlarged view of the first embodiment
shown in FIG. 2.
[0034] FIGS. 8 and 9 are schematic views illustrating the
positioning of the device of FIGS. 2 and 3 in the coronary
sinus,
[0035] FIGS. 10 and 11 are schematic views illustrating the
positioning of a second embodiment of the device according to the
present invention in the coronary sinus,
[0036] FIGS. 12 and 13 are schematic views illustrating the
positioning of a third embodiment of the device according to the
present invention in the coronary sinus.
[0037] FIG. 14 illustrates a fourth embodiment of the device
according to the present invention.
[0038] FIG. 15 is a schematic view illustrating a preferred
operation of the fourth embodiment.
[0039] FIG. 16 is a schematic view illustrating the operation of a
fifth embodiment of the device according to the present
invention.
[0040] FIG. 17 illustrates a sixth embodiment of the device
according to the present invention.
[0041] FIG. 18 illustrates a further modification of the
embodiments of FIGS. 14-17.
[0042] FIGS. 19 and 20 illustrate a seventh embodiment of the
device according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0043] FIG. 1 is a cross-sectional view through the heart area of
the posterior atrioventricular groove 1, which is filled with fatty
tissue. It shows the posterior leaflet of the mitral valve and the
adjoining parts 3, 4 of the atrial myocardium and the ventricular
myocardium. The coronary sinus 5 is shown close to the mitral
annulus 6 and behind the attachment 7 of the posterior leaflet 2.
Since the coronary sinus 5 substantially encircles the mitral
annulus 6, a reduction of the radius of curvature of the bent
coronary sinus 5 also will result in a diameter and circumference
reduction of the mitral 5 annulus 6.
[0044] The device of FIG. 2 comprises an elongate body 8 made of
memory metal, e.g. Nitinol, or other similar material which has a
memory of an original shape, illustrated in FIG. 3, and can be
temporary forced into another shape, illustrated in FIG. 2. This
elongate body 8 comprises one, two or more memory metal strings 9
of helical or other shape so as to fit together and be able of
permitting the movements described below. Along the elongate body 8
several hooks 10 are fastened so as to extend radially out
therefrom. These hooks 10 are covered by a cover sheath 11 in FIG.
2.
[0045] The elongate body 8 is forced into a stretched or extended
state by means of a stabilizing instrument 12 shown in FIG. 4. This
instrument 12 has two arms 13 at a distal end 14 of a rod 15 and a
locking means 16 at a proximal end of the rod 15. The distance
between the ends of the rod 15 corresponds to the desired length of
the elongate body 8 when being insert d into the coronary sinus
5.
[0046] The arms 13 are free to move between the position shown in
FIG. 4 and a position in alignment with the rod 15, as shown in
FIG. 6. The locking means 16 has two locking knobs 17, which are
pressed radially outwards from the rod 15 by two spring blades 18.
Thus, the elongated body 8 can be pushed over the rod 15 of the
stabilizing instrument 12, then stretched between the arms 13 and
the knobs 17, and finally locked in its stretched state on the
stabilizing instrument 12 between the arms 13 and the knobs 17, as
illustrated in FIG. 5.
[0047] The rod 15 may be a metal wire which is relatively stiff
between the distal end 14 and the locking means 16 but still so
bendable that it will follow the shape of the coronary sinus 5.
Proximally of the locking means 16 the metal wire of the
stabilizing instrument 11 is more pliable to be able to easily
follow the bends of the veins.
[0048] The above-described elongate body 8 is positioned in the
coronary sinus 5 in the following way:
[0049] An introduction sheath (not shown) of synthetic material may
be used to get access to the venous system. Having reached access
to the venous system, a long guiding wire (not shown) of metal is
advanced through the introduction sheath and via the venous system
to the coronary sinus 5. This guiding wire is provided with X-ray
distance markers so that the position of the guiding wire in the
coronary sinus 5 may be monitored.
[0050] The elongate body 8 is locked onto the stabilizing
instrument 12, as shown in FIG. 5, and introduced into the long
cover sheath 11 of synthetic material. This aggregate is then
pushed through the introduction sheath and the venous system to the
coronary sinus 5 riding on the guiding wire. After exact
positioning of the elongate body B in the coronary sinus 5, as
illustrated in FIG. 8 where the mitral valve 19 is shown having a
central gap 20, the cover sheath 11 is retracted exposing the
elongate body 8 within the coronary sinus 5. This maneuver allows
the hooks 10 on the elongate body 8 to dig into the walls of the
coronary sinus 5 and into the heart. The elongate body 8 is still
locked on to the stabilizing instrument 12 such that the hooks 10
engage the walls of the coronary sinus 5 in the stretched or
extended state of the elongate body 8.
[0051] A catheter 21, shown in FIG. 6, is pushed forward on the
guiding wire and the rod 15 for releasing the elongate body 8 from
the locking means 16 by pressing the spring blades 18 towards the
rod 15. This movement releases the knobs 17 as well as the arms 13
from engagement with the elongate body 8 which contracts as
illustrated in FIG. 9, thereby shortening the radius of curvature
of the coronary sinus. As a result, the mitral valve annulus 6
shrinks moving the posterior part thereof forward (shown by arrows
in FIG. 9). This movement reduces the circumference of the mitral
valve annulus 6 and thereby closes the central gap 20.
[0052] FIG. 7 illustrates a part of an arrangement of the wires 9
and the hooks 10 along a peripheral part of the elongate body 8,
whereby the elongate body 8 will be asymmetrically contracted
resulting in a bending thereof when interconnecting parts 22 of at
least some of the hooks 10 are shortened to an original shape.
[0053] FIGS. 10 and 11 illustrate an alternative embodiment of an
elongate body 8', which is a solid wire in the shape of an open
U-shaped ring that will engage the wall of the coronary sinus 5
most adjacent to the mitral valve annulus 6 when inserted into the
coronary sinus 5. The elongate body 8' consists of a memory metal
material which when reverting to its original shape will bend as
illustrated in FIG. 11. The return of the open ring 8' to its
original shape may be initiated in several ways, as is obvious to
the man skilled in the art.
[0054] The third embodiment of the elongate body 8", illustrated in
FIGS. 12 and 13, comprises three stent sections 23-25 positioned at
one end of the elongate body 8", at the middle thereof and at the
other end of the elongate body 8", respectively. These stent
sections 23-25 may be positioned in the coronary sinus 5 as
illustrated by conventional means, such that their positions are
fixed. They are connected by wires 26, 27, which may be maneuvered
from outside the vein system such that the distances between the
adjacent stent sections 23, 24 and 24, 25 are reduced. More
specifically, these distances are reduced asymmetrically, i.e. more
on the side of coronary sinus 5 most adjacent to the posterior part
of the mitral valve annulus 6. Thereby, the elongate body 8" is
bent, as illustrated in FIG. 13, and presses the coronary sinus 5
against the mitral valve annulus 6 closing the gap 20.
[0055] A fourth embodiment of the device is shown in FIG. 14 as
comprising two stent sections, more precisely a proximal stent
section 30 and a distal stent section 31. The fourth embodiment
further comprises a first eyelet 32, which is fixed to a preferably
proximal part of the the distal stent section 31, a second eyelet
33, which is fixed to a preferably distal part of the proximal
stent section 30, and a third eyelet 34, which is positioned
between the proximal and distal stent sections 30, 31. These
sections 30, 31 are joined by a wire 35, one end of which is fixed
to the the distal stent section 31. The wire 35 may be fixed to th
distal stent section 31 at a proximal point, as shown in FIG. 14,
or at a more distal point up to the distal end of the distal stent
section 31.
[0056] From the distal stent section 31 the wire 35 extends to and
through the third eyelet 34 and then back towards the distal stent
section 31 to and through the first eyelet 32. From the first
eyelet 32 the wire 35 then extends to and through the second eyelet
33 and then finally to the third eyelet 34, the other end of the
wire 35 being fixed to this third eyelet 34.
[0057] By moving the third eyelet 34 towards the proximal stent
section 30, the distance between the proximal and distal stent
sections 30, 31 will be reduced. On the contrary, by moving the
third eyelet 34 towards the distal stent section 31, the distance
between the proximal and distal stent sections may be increased.
However, such increase will require some means pushing the distal
stent section 31 in a distal direction away from the proximal stent
section 30 or pulling the proximal stent section in a proximal
direction away from the distal stent section 31.
[0058] The distance between the proximal and distal stent sections
30, 31 will reach a maximum when the third eyelet 34 is positioned
close to the distal stent section 31 and will reach a minimum when
the third eyelet 34 is positioned close to the proximal stent
section 30.
[0059] The third eyelet 34 may be moved towards the proximal stent
section 30 by means of a single wire 36, which has an end
releasably fixed to the third eyelet 34 and extends proximally
therefrom through the proximal stent section 30 and furter
proximally out of the coronary sinus 5, through the vein system and
out of the human body.
[0060] In a preferred embodiment schematically illustrated in FIG.
15, a second wire 37 extends through the third eyelet 34 and
further extends as a double wire proximally from the third eyelet
34, through the proximal stent section 30 and the coronary sinus 5
and then out of the body. The third eyelet 34 will be moved
proximally by simultaneous pulling both ends of the second wire 37
outside of the body. When the desired position of the third eyelet
34 is reached, the second wire 37 may easily be removed through the
vein system by pulling only one of its ends outside the body.
[0061] As illustrated in FIG. 15, a third wire 38 may be extended
through the third eyelet 34. Therefrom it extends as a double wire
distally to and through the first eyelet 32 and then this double
wire extends proximally from the first eyelet 32 (or a further
eyelet fixed to the proximal end of the distal stent) through the
proximal stent section 30 and finally the double wire 38 extends
proximally through the coronary sinus 5 and out of the human body.
By pulling both ends of this third wire 38 outside of the body, the
third eyelet 34 will allow a movement of the proximal and distal
stent sections 30, 31 away from each other. By means of the second
wire 37 and the third wire 38 the position of the third eyelet 34
may be adjusted repeatedly until a desired position is attained.
The third wire 38 may be removed in the same manner as the second
wire 37.
[0062] Obviously, the position of the third eyelet 34 may be used
to control the distance between the proximal and distal Stent
sections 30, 31, and this distance controls the radius of curvature
of the device and thus also the radius of curvature of the coronary
sinus 5.
[0063] The furter embodiment of the device illustrated in FIG. 16
corresponds to the embodiment illustrated in FIG. 15 except that
the first eyelet 32 is fixed to the proximal stent section 30 and
the second eyelet 33 is fixed to the distal stent section 31.
Therefore, a fourth wire 39 has the same extension as the third
wire 38 in FIG. 15 but has the function of the second wire 37 in
FIG. 15. A fifth wire 40 has the same extension as the second wire
37 in FIG. 15 but has the function of the third wire 38 of FIG.
15.
[0064] The quotient between the maximum distance and the minimum
distance between the proximal stent section 30 and the distal stent
section 31 in FIGS. 15 and 16 is about 1.5. A quotient of about 2.5
would be possible by letting the wire 35 extend once more via the
third eyelet 34 and the first eyelet 32 (or another eyelet fixed at
substantially the same position as the first eyelet) before finally
extending via the second eyelet 33 back to the third eyelet 34
where the second end of the wire 35 is fixed, as shown in FIG.
17.
[0065] According to FIG. 18, the wires 35-40 extending between the
proximal stent section 30 and the distal stent section 31 are
confined in a plastic sheath or a plastic wire spiral 41 which will
cover and protect the wires 35-40. By enclosing the wires 35-40,
the sheath or spiral 41 will also prohibit them from cutting
through the wall of the coronary sinus 5. Alternatively, more than
one sheath or spiral 41 may be used, all of which should be
compressible lengthwise so as to allow the reduction of the
distance between the proximal and distal stent sections 30, 31.
[0066] The embodiments illustrated in FIGS. 15-18 may be introduced
by conventional means into the coronary sinus 5 via the vein
system. Preferably, the distal stent section 31 first is adjusted
to a desired position, whereupon it is expanded so as to engage the
walls of the coronary sinus 5. Thereby, the position of the distal
stent section 31 is fixed in the coronary sinus 5. Then the
position of the proximal stent section 30 is adjusted considering
the required reduction of the distance between the the proximal and
distal stent sections 30, 31. Thereafter the proximal stent section
30 is expanded such that it is fixed relative the coronary sinus 5.
Finally, the distance between the proximal and distal stent
sections 30, 31 is reduced using one of the wires 37 and 39. If the
distance reduction is found too extensive, the distance between the
stent sections 30 and 31 may be increased by pulling one of the
wires 38 and 40. After achieving a perfect position, the used wires
37-40 may be removed by pulling in one of the double ends.
[0067] It should be noted that instead of eyelets having a single
opening, eyelets having multiple openings could be used such that
each one of the wires extends through an opening of its own.
[0068] Still one further embodiment of the device according to the
present invention is illustrated in FIGS. 19 and 20. Here, the
device comprises an elongate body having three stent sections, the
proximal stent section 30 and the distal stent section 31 being of
the same type as described above. A central stent section 42 is
such as to reduce its length when expanded radially.
[0069] When this device is positioned in the coronary sinus 5, the
proximal and distal sections 30, 31 are first expanded, as
illustrated in FIG. 19, and then the central stent section 42 is
expanded. As a consequence of its length reduction when expanded,
the central stent section 42 will reduce the distance between the
proximal and distal stent sections 30, 31 and thus reduce the
radius of curvature of the coronary sinus 5 as illustrated in FIG.
20.
[0070] Concludingly, the present invention provides a device placed
in the coronary sinus 5 and designed to reduce the dilatation of
the mitral annulus. This device is at a distance from the
attachment of the posterior leaflet that does not much exceed the
distance at which present annuloplasty rings are placed by open
surgery techniques, and the coronary sinus is along its entire
course large enough to hold such a device. The device could be
positioned by catheter technique or any other adequate technique
and offers a safer alternative to the current open surgery methods.
The device could be designed or heparincoated so as to avoid
thrombosis in the coronary sinus, thus reducing the need for
aspirin, ticlopedine or anticoagulant therapy.
[0071] It is to be understood that modifications of the
above-described device and method can be made by people skilled in
the art without departing from the spirit and scope of the
invention.
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