U.S. patent application number 10/401907 was filed with the patent office on 2003-12-11 for mitral valve annuloplasty ring.
This patent application is currently assigned to Cardiac Concepts, Inc.. Invention is credited to Cox, James L..
Application Number | 20030229395 10/401907 |
Document ID | / |
Family ID | 23579534 |
Filed Date | 2003-12-11 |
United States Patent
Application |
20030229395 |
Kind Code |
A1 |
Cox, James L. |
December 11, 2003 |
Mitral valve annuloplasty ring
Abstract
A mitral valve annuloplasty ring and method for implanting a
mitral valve annuloplasty ring to treat mitral insufficiency by
reestablishing the normal shape and contour of the mitral valve
annulus. The annuloplasty ring is flexible and can be readily
adjusted to different sizes and shapes. The method substantially
eliminates scarring subsequent to the annuloplasty procedure to
maintain flexibility of the ring and the annulus indefinitely.
Inventors: |
Cox, James L.; (McLean,
VA) |
Correspondence
Address: |
Boyd D. Cox, Attorney at Law
Suite 506
75 N. East Avenue
Fayetteville
AR
72701
US
|
Assignee: |
Cardiac Concepts, Inc.
3200 TCBY Tower
Little Rock
AR
72201
|
Family ID: |
23579534 |
Appl. No.: |
10/401907 |
Filed: |
March 28, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10401907 |
Mar 28, 2003 |
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09776124 |
Feb 2, 2001 |
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6565603 |
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09776124 |
Feb 2, 2001 |
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09399444 |
Sep 17, 1999 |
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6250308 |
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09399444 |
Sep 17, 1999 |
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09097763 |
Jun 16, 1998 |
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Current U.S.
Class: |
623/2.36 |
Current CPC
Class: |
Y10S 623/904 20130101;
A61F 2/2448 20130101 |
Class at
Publication: |
623/2.36 |
International
Class: |
A61F 002/24 |
Claims
1. An annuloplasty ring for repairing a valve in a patient's heart,
said annuloplasty ring comprising: (a) a first section for
implanting adjacent to the valve; and (b) a second flexible section
for implanting within a fat pad of an atrioventricular groove in
the heart.
2. The annuloplasty ring of claim 1, wherein said second flexible
section comprises a proximal end and a distal end and a means for
joining the distal end to a needle.
3. The annuloplasty ring of claim 2, further comprising a needle
having an attaching end with an outer diameter.
4. The annuloplasty ring of claim 3, wherein said means for joining
the distal end to the needle comprising a frictional
engagement.
5. The annuloplasty ring of claim 4, wherein said first section
further comprises a first and second end, said first and second
ends having an outer diameter; said annuloplasty ring further
comprising: (a) a first means for joining the distal end of the
second flexible section to the second end of the first section; and
(b) a second means for joining the proximal end of the second
flexible section to the first end of the first section.
6. The annuloplasty ring of claim 5, wherein said first means for
joining comprises a frictional engagement and said second means for
joining comprises a frictional engagement.
7. The annuloplasty ring of claim 6, wherein said outer diameters
of said first and second ends are approximately equal to said inner
diameter of said hollow inner portion, and said frictional
engagement of said first means for joining is between said inner
diameter of said hollow inner portion at said distal end and said
outer diameter of said second end, and said frictional engagement
of said second means for joining is between said inner diameter of
said hollow inner portion at said proximal end and said outer
diameter of said first end.
8. The annuloplasty ring of claim 5, further comprising: (a) an
open configuration wherein said first section is attached to said
second section by said second means for joining and said second end
of said first section and said distal end of said second flexible
section are unattached; (b) a closed configuration wherein said
first section is attached to said second section by said first and
second means for joining, thereby forming a loop; and (c) a
surgical configuration wherein said first section is attached to
said second section by said first means for joining and said second
flexible section is attached to the needle by said means for
joining said distal end of said second flexible section to said
needle.
9. The annuloplasty ring of claim 4, wherein the distal end of the
flexible section further comprises a hollow inner portion with an
inner diameter approximately equal to the outer diameter of the
attaching end of the needle and said frictional engagement is
between said inner diameter and said outer diameter of the
attaching end.
10. The annuloplasty ring of claim 1, wherein said first section is
rigid with first and second ends being substantially straight, said
first section further having a bow between the first and second
ends.
11. The annuloplasty ring of claim 1, further comprising a means
for sizing the ring.
12. A method for implanting an annuloplasty ring in a patient's
heart, comprising: implanting a flexible section of the
annuloplasty ring in the fat pad of the atrioventricular groove of
the heart; positioning a rigid section of the annuloplasty ring
adjacent to the valve annulus; and forming the annuloplasty ring
into a closed loop.
13. The method of claim 12, wherein the annuloplasty ring includes
a needle attached to the flexible section.
14. The method of claim 13, wherein the steps of implanting a
substantial portion of the annuloplasty ring in the fat pad of the
atrioventricular groove further comprises: inserting the tip of the
needle through the endocardium and the left atrial myocardial wall
from the endocardial aspect at the right fibrous trigone; passing
the needle and a portion of the annuloplasty ring through the
endocardium and the left atrial myocardial wall from the
endocardial aspect, at the right fibrous trigone; passing the
needle and a portion of the annuloplasty ring in a posterior
direction, external to and parallel to the mitral valve annulus;
and inserting the tip of the needle through left atrial myocardial
wall from the epicardial aspect and back through the endocardium at
the left fibrous trigone; passing the needle and a portion the
annuloplasty ring back through the left atrial myocardial wall from
the epicardial aspect and back through the endocardium at the left
fibrous trigone.
15. The method of claim 14, wherein positioning the rigid n further
comprises: positioning the flexible section in a substantial
parallel orientation with the posterior portion of the mitral valve
annulus, by pulling the needle; aligning the rigid section of the
annuloplasty ring along an anterior portion of the mitral valve
annulus; and positioning the bow of the rigid section to conform
with a contour of the mitral valve annulus adjacent the aortic
valve root.
16. The method of claim 13, further comprising: determining the
appropriate size of the annuloplasty ring after implanting and
positioning the ring and before forming the ring into a closed
loop; and cutting the annuloplasty ring to the appropriate
size.
17. The method of claim 16, further comprising: detaching the
needle from the annuloplasty ring after implanting and positioning
the ring and before determining the appropriate size.
18. The method of claim 16, wherein the step of forming the
annuloplasty ring into a closed loop further comprises: joining a
second end of the rigid section to a distal end of the flexible
section by inserting the second end of the rigid section into a
hollow inner portion of the distal end of the flexible section.
19. The method of claim 12, further comprising: suturing the
annuloplasty ring to the valve annulus at the left and right
fibrous trigones.
20. The method of claim 19, further comprising: suturing the
annuloplasty ring within the fat pad of the atrioventricular
groove.
21. A kit for an annuloplasty ring comprising: (a) a first section;
(b) a second flexible section having a proximal end and a distal
end; (c) a means for joining the distal end of the second flexible
section to a needle.
22. The kit for an annuloplasty ring in claim 21, further
comprising a needle having an attaching end with an outer
diameter.
23. The kit for an annuloplasty ring in claim 22, wherein said
means for joining the distal end to the needle comprising a
frictional engagement.
24. The kit for an annuloplasty ring in claim 23, wherein said
first section further comprises a first end and a second end, said
first and second ends having an outer diameter, and said
annuloplasty ring further comprising: (a) a first means for joining
the distal end of the second flexible section to the second end of
the first section; and (b) a second means for joining the proximal
end of the second flexible section to the first end of the first
section.
25. The kit for an annuloplasty ring in claim 24, wherein said
first means for joining comprises a frictional engagement and said
second means for joining comprises a frictional engagement, said
second flexible section includes a hollow inner portion at the
distal and proximal ends, said hollow inner portion having an inner
diameter approximately equal to the outer diameters of the first
and second ends of the first section, wherein said frictional
engagement of said first means for joining is between said inner
diameter of said hollow inner portion at said distal end and said
outer diameter of said second end, and said frictional engagement
of said second means for joining is between said inner diameter of
said hollow inner portion at said proximal end and said outer
diameter of said first end.
26. The kit for an annuloplasty ring of claim 23, wherein the
distal end of the second flexible section further comprises a
hollow inner portion with an inner diameter approximately equal to
the outer diameter of the attaching end of the needle and said
frictional engagement of said means for joining the distal end to a
needle is between said inner diameter and said outer diameter of
the attaching end.
27. The kit for an annuloplasty ring of claim 21, wherein said
second flexible section further comprising a means for sizing the
ring.
28. An annuloplasty ring for use in an annuloplasty surgical
procedure to correct mitral insufficiency in a patient by restoring
the mitral valve annulus to a normal shape and flexibility which is
determined by the movement of the left ventricle, the mitral valve
and the mitral valve annulus, wherein said annuloplasty ring
comprises: a first rigid section having a first end, a second end
and a length, said first and second ends having an outer diameter;
a second flexible section having a distal end, a proximal end, a
length, a means for sizing the ring, and at least one hollow inner
portion with an exterior opening at the proximal and distal ends
and an inner diameter; a round-tip needle having a tip and an
attaching end with an outer diameter; a first means for joining the
distal end of the second section to the second end of the first
section; a second means for joining the proximal end of the second
section to the first end of the first section; a third means for
joining the distal end of the second section to the needle; wherein
said outer diameters of the first section and the outer diameter of
the attaching end are approximately equal to the inner diameter of
the hollow inner portion and said length of said second flexible
section is greater than said length of said first rigid section;
said first means for joining comprising a frictional engagement
between the inner diameter of the hollow inner portion at the
distal end and the outer diameter of the second end; said second
means for joining comprising a frictional engagement between the
inner diameter of the hollow inner portion at the proximal end and
the outer diameter of the first end; and said third means for
joining comprising a frictional engagement between the inner
diameter of the hollow inner portion at the distal end and the
outer diameter of the attaching end of the needle; said means for
sizing the ring further comprising measurement indicia on the
distal end of the second section; said first rigid section is
substantially straight and further comprises a bow positioned
between the first and second ends; the annuloplasty ring further
comprising: (1) an open configuration defined by said first section
being joined to said second section by said second means for
joining, wherein the exterior opening and hollow inner portion at
the proximal end of the second section receive the first end of the
first section therein, the first end and the proximal end are held
together by said frictional engagement, and said second end and
said distal end being unattached; (2) a surgical configuration
defined by said first section being joined to said second section
and said needle by said second and third means for joining, wherein
said exterior opening and hollow inner portion at the proximal end
of the second section receive the first end of said first section
therein, the first end and proximal end are held together by said
frictional engagement of said second means for joining and said
distal end of said second section, and the exterior opening and
hollow inner portion at the distal end of the second section
receive the attaching end of the needle therein, the distal end and
the attaching end are held together by said frictional engagement
of the third means for joining; and (3) a closed configuration
defined by said first section being joined to said second section
by said first and second means for joining, wherein the exterior
opening and the hollow inner portion at the proximal end of said
second section receive the first end of said first section therein,
the proximal end and the first end are held by said frictional
engagement of said second means for joining, and said exterior
opening and the hollow inner portion at the distal end of the
second section receive the second end of the first section therein,
the distal end and the second end are held by said frictional
engagement of said first means for joining; wherein said first
rigid section for implantation adjacent to an anterior portion of
the mitral valve annulus and said second section for implantation
in the fat pad of the atrioventricular groove.
29. A method for implanting an annuloplasty ring in a patient's
heart to correct mitral insufficiency in which the mitral valve
annulus is restored to a normal shape and flexibility as determined
by the movement of the left ventricle, the mitral valve and the
mitral valve annulus, the steps comprising: (1) providing an
annuloplasty ring having an elongated flexible section attached at
one end to a rigid section with a bow and attached at an opposite
end to a round tipped-needle; (2) inserting the tip of the needle
through the endocardium and the left atrial myocardial wall of the
heart from the endocardial aspect, at the right fibrous trigone;
(3) passing the needle and a portion of the annuloplasty ring
through the endocardium and the left atrial myocardial wall of the
heart from the endocardial aspect, at the right fibrous trigone;
(4) passing the needle and a portion of the annuloplasty ring in a
posterior direction just external to and parallel to the mitral
valve annulus; (5) passing the needle and a portion of the
annuloplasty ring around the outside of the mitral valve annulus in
the fat pad of the atrioventricular groove in a clockwise direction
to the left fibrous trigone; (6) inserting the tip of the needle
back through the left atrial myocardial wall and the endocardium
from the epicardial aspect at the left fibrous trigone; (7) passing
the needle and a portion of the annuloplasty ring back through the
left atrial myocardial wall from the epicardial aspect and back
through the endocardium at the left fibrous trigone; (8)
positioning the flexible section substantially parallel to a
posterior portion of the mitral valve annulus; (9) aligning the
rigid section along an anterior portion of the mitral valve
annulus, (10) positioning the bow of the rigid section conforms to
a contour of the mitral valve annulus adjacent the aortic valve
root and further positioning the flexible section around a
posterior portion of the mitral vale annulus; (11) detaching the
needle from the flexible section; (12) determining the appropriate
size of the annuloplasty ring; (13) cutting the flexible section of
the annuloplasty to the appropriate size; (14) closing the
annuloplasty ring by affixing the distal end of the flexible
section to the second end of the rigid section by inserting the
rigid section into the inner hollow portion of the flexible
section; (15) suturing the annuloplasty ring to valve annulus which
at the left and right fibrous trigones; (16) suturing one point
along the posterior section of the mitral valve annulus to the
flexible section of the annuloplasty ring.
30. A kit for an annuloplasty ring to be used in an annuloplasty
surgical procedure to correct mitral insufficiency in a patient by
restoring the mitral valve annulus to a normal shape and
flexibility which is determined by the movement of the left
ventricle, the mitral valve and the mitral valve annulus, wherein
said annuloplasty ring comprises: a first rigid section having a
first end, a second end, a length and an outer diameter; a second
flexible section having a distal end, a proximal end, a length, a
means for sizing the ring, and at least one hollow inner portion
with an exterior opening at the distal and proximal ends and an
inner diameter; a round-tip needle having a tip and an attaching
end with an outer diameter; a first means for joining the distal
end of the second section to the second end of the first section; a
second means for joining the proximal end of the second section to
the first end of the first section; a third means for joining the
distal end of the second section to the needle; wherein said outer
diameter of the first section and the outer diameter of the
attaching end are approximately equal to the inner diameter of the
hollow inner portion; said first means for joining comprising a
frictional engagement between the inner diameter of the hollow
inner portion at the distal end and the outer diameter of the
second end when the two ends are joined; said second means for
joining comprising a frictional engagement between the inner
diameter of the hollow inner portion at the proximal end and the
outer diameter of the first end when the two ends are joined; and
said third means for joining comprising a frictional engagement
between the inner diameter of the hollow inner portion at the
distal end and the outer diameter of the attaching end of the
needle when the two ends are joined.
Description
BACKGROUND
[0001] The present invention is directed to a mitral valve
annuloplasty ring and a method for implanting a mitral valve
annuloplasty ring to treat mitral insufficiency in a patient.
Mitral insufficiency, also known as mitral regurgitation, is a
common cardiac abnormality wherein the heart's mitral valve does
not properly close.
[0002] In a normally functioning heart, oxygenated blood passes
from the left atrium through the opened mitral valve and into the
left ventricle when the left ventricle is in a relaxed state. When
the left ventricle contracts, the blood is pushed out of the left
ventricle thereby closing the mitral valve to prevent blood flowing
back or regurgitating into the left atrium. From the left
ventricle, the oxygenated blood is pumped out of the heart and
directed to the rest of the body.
[0003] With mitral insufficiency, the mitral valve does not fully
close and a portion of blood leaks back into the left atrium when
the left ventricle contracts. As a result, the heart has to work
harder by pumping not only its regular volume of blood, but also
the extra volume of blood that regurgitates back into the left
atrium. The added workload creates an undue strain on the left
ventricle. This strain can eventually wear out the heart and result
in death when the condition is prolonged and severe enough.
Consequently, a properly functioning mitral valve is critical to
the pumping efficiency of the heart.
[0004] Mitral valve annuloplasty is a well known approach for
treating mitral insufficiency, although other treatments are used
which include replacing the mitral valve, repairing the mitral
valve leaflets, and shortening or replacing the chordae tendinae.
Mitral valve annuloplasty is the reparation of the mitral valve
annulus which effects full closure of the leaflets by
reestablishing the size and shape of the normal mitral valve
annulus. Such an annuloplasty most commonly incorporates the use of
a mitral annuloplasty ring wherein the ring is implanted on the
mitral valve annulus.
[0005] There are three basic types of mitral annuloplasty rings
used in annuloplasty procedures. They include a rigid ring, a
flexible ring and a combined ring that has both a flexible
component and a rigid component.
[0006] Due to their inflexibility, the rigid rings dictate the
shape and contour of the mitral valve. The native mitral valve
annulus flexes in response to the movement of the heart. However,
with a rigid ring the annulus is not able to flex normally or move
freely with the pumping action of the heart. As a result of the
rigidity, the physiologic factors that normally shape the mitral
valve annulus are not allowed to take precedence in shaping the
valve.
[0007] Another drawback with rigid rings is that they can induce a
heart condition known as systolic anterior motion in patients
having a mitral valve posterior leaflet that is too "tall". During
ventricular contraction, the posterior leaflet pushes the anterior
leaflet in a direction opposite to the anterior leaflet's normal
movement, resulting in the obstruction of the left ventricle's
outflow tract.
[0008] Overall, rigid annuloplasty rings do not allow the mitral
valve annulus to reestablish its normal shape and form as dictated
by the action of the heart pumping. The shape and contour of the
annulus is established by the inflexible shape and form of the ring
itself.
[0009] Flexible rings made of Dacron cloth, unlike the rigid rings,
can allow the mitral valve annulus to move and flex as the heart
contracts and relaxes. However, several drawbacks still exist.
Proper shape and contour of the annulus is necessary in order for
the mitral valve leaflets to close effectively. One shortcoming of
the flexible ring is its predisposition to crimp during
implantation. Crimping can be detrimental to the valve annulus,
sometimes resulting in a mitral orifice that is too small. This can
lead to stenosis of the valve. Furthermore, neither the flexible
rings nor the combined rings will remain flexible indefinitely
after annuloplasty. Since the rings are secured in place by a line
of sutures attached directly to the annulus, scarring and resultant
stiffening of the annulus inevitably develops. This loss of
flexibility impedes the normal flexing and movement of the heart,
particularly the left ventricle and, therefore, the heart cannot
function optimally.
SUMMARY
[0010] The annuloplasty ring of the present invention is a combined
ring which comprises a first section that is substantially rigid
and a second flexible section. The ring can be readily adjusted to
fit the annulus of any particular patient. The method of implanting
the annuloplasty ring of the present invention comprises installing
a ring within the fat pad of the atrioventricular groove which
surrounds the mitral valve annulus. The method does not require a
series of sutures extending through the mitral valve annulus tissue
to hold the ring in place. Resultant scarring and stiffening of the
annulus is thereby substantially eliminated.
[0011] The ring of the present invention when combined with the
method of the present invention is positioned in the fat pad of the
atrioventricular groove adjacent to the mitral valve annulus. The
flexible section of the ring extends adjacent to the flexible
posterior portion of the annulus, while the rigid section of the
ring spans the substantially rigid inter-trigone section of the
annulus. Since the flexible section of the ring is held in the
atrioventricular groove of the posterior section of the annulus, it
is not necessary to suture the flexible section directly to the
mitral valve annulus. As a result, scarring of the annulus is
substantially eliminated, thereby allowing the ring and annulus to
remain flexible indefinitely. As in the normal heart, this
flexibility enables the mitral valve annulus to flex in several
planes during contraction and relaxation of the heart. The result
is better postoperative functioning of the mitral valve and better
postoperative functioning of the left ventricle, as well.
[0012] It is an object of the present invention to provide an
annuloplasty ring that reestablishes the normal shape and contour
of the mitral valve annulus.
[0013] It is a further object of the present invention to provide a
method for performing an annuloplasty that substantially eliminates
scarring of the mitral valve annulus tissue to preclude the loss of
flexibility following the annuloplasty.
[0014] It is a further object of the present invention to provide a
method for implanting the annuloplasty ring that allows the ring to
maintain flexibility indefinitely.
[0015] It is a further object of the invention to provide an
annuloplasty ring that is flexible enough to allow the mitral valve
and annulus to flex through different planes, yet positioned such
that the shape and contour of a normal mitral valve annulus is
reestablished.
[0016] It is a further object of the present invention to provide a
flexible annuloplasty ring that does not crimp during
implantation.
[0017] It is a further object of the present invention to provide
an annuloplasty ring that can be flexed in all manner that the
native mitral valve annulus flexes.
[0018] It is a further object of the present invention to provide
an annuloplasty ring and method of implanting the ring that
maintains flexibility of the ring and the mitral valve annulus
indefinitely.
[0019] It is a further object of the present invention to provide a
method for implanting the annuloplasty ring that minimizes scarring
of the mitral valve annulus and nearby tissue.
[0020] It is a further object of the present invention to provide
an annuloplasty ring that assumes the shape of the normal mitral
valve annulus to allow for effective functioning of the valve.
[0021] It is a further object of the present invention to provide
an annuloplasty ring and method of implanting the ring that result
in effective coaptation of the anterior and posterior leaflets of
the mitral valve.
[0022] It is a further object of the present invention to provide
an annuloplasty ring and method of implanting an annuloplasty ring
that do not impede the movement of the left ventricle's base when
the ventricle is contracting and relaxing, thereby allowing
effective functioning of the left ventricle.
[0023] It is a further object of the present invention to provide
an annuloplasty ring and a method of surgically implanting an
annuloplasty ring that allow the base of the left ventricle to
assume its full range of movement when contracting and relaxing to
allow effective functioning of the left ventricle.
[0024] It is a further object of the present invention to provide
an annuloplasty ring that allows the left ventricle to move
naturally as the heart pumps and allows the mitral valve annulus to
flex freely in response to the movement of the left ventricle.
[0025] It is a further object of the present invention to provide
an annuloplasty ring and a method of implanting the annuloplasty
ring that does not require a plurality of sutures along the
posterior portion of the mitral valve annulus to secure the ring in
place.
[0026] It is a further object of the present invention to provide
an annuloplasty ring that can be readily adjusted in size.
[0027] It is a further object of the present invention to provide
an annuloplasty ring that can be readily adjusted in shape by
adjusting the circumference of the ring.
[0028] It is a further object of the present invention to provide a
kit for an annuloplasty ring that reestablishes the normal shape to
and contour of the mitral valve annulus.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] FIGS. 1A-1F are cutaway views of the heart as seen from the
atrial position depicting a preferred method of implanting the
mitral valve annuloplasty ring in the atrioventricular groove.
[0030] FIG. 2A is a top view of a preferred embodiment of the
mitral valve annuloplasty ring of the present invention in a closed
configuration.
[0031] FIG. 2B is a side view of the mitral valve annuloplasty ring
in a closed configuration.
[0032] FIG. 3 is an exploded view of the mitral valve annuloplasty
ring with needle.
[0033] FIG. 4 is a schematic cross sectional side view of a portion
of the heart depicting the atrioventricular groove with the
annuloplasty ring implanted therein.
[0034] FIG. 5 is a view of the mitral valve annuloplasty ring in a
surgical configuration.
[0035] FIG. 6 is a view of the mitral valve annuloplasty ring in an
open configuration.
DETAILED DESCRIPTION
[0036] The left ventricle is the main pumping chamber of the heart.
Oxygenated blood from the lungs enters the left atrium and passes
into the left ventricle through the mitral valve. The blood is
pumped from the left ventricle to the rest of the body.
[0037] As shown in FIGS. 1A-1F, the mitral valve (30) is a one way
passive valve comprising a pair of leaflets, including a larger
anterior leaflet (32) and a smaller posterior leaflet (33). The
leaflets open and close in response to pressure differences in the
heart (5) on either side of the mitral valve (30). The base of each
anterior (32) and posterior (33) leaflet is attached to the mitral
valve annulus (34).
[0038] The contour of the mitral valve annulus (34) refers to the
outline or form of the annulus (34) when viewed in the general
plane of the annulus (34). The shape of the annulus (34) is that
shape viewed from the atrial side of the mitral valve (30),
"looking down" on the mitral valve annulus (34).
[0039] The mitral valve annulus (34) includes a posterior portion
(35) and an anterior portion (36). The anterior portion (36), also
known as the inter-trigone segment or section, is a generally
straight, substantially rigid segment. The posterior portion (35)
of the annulus (34) is a flexible, curvilinear segment that
encompasses a larger proportion of the annulus circumference than
the anterior portion (36). The right (37) and left (38) fibrous
trigones mark the ends of the generally straight segment and define
the intersection points between the posterior (35) and anterior
portions (36).
[0040] Referring to FIGS. 2A and 2B, there is shown a preferred
embodiment of the annuloplasty ring (10) comprising the present
invention. The ring (10) comprises a first section (11) and a
second section (15). The first section (11) has a first end (12)
and a second end (13), while the second section (15) includes a
proximal end (16) and a distal end (17). A means for sizing the
annuloplasty ring (10) includes measurement indicia (18) extending
inwardly from an outermost edge of the second section's distal end
(17). The annuloplasty ring (10) also includes a detachable needle
(20) having a tip (72) and an attaching end (73) as shown in FIG.
3.
[0041] The annuloplasty ring (10) comprises a first means for
joining the second end of the first section to the distal end of
the second section and a second means for joining the first end of
the first section to the proximal end of the second section. The
ring (10) also comprises a third means for joining the second end
of the second section to the needle.
[0042] In one preferred embodiment, the first means for joining the
second end of the first section to the distal end of the second
section, the second means for joining the first end of the first
section to the proximal end of the second section, and the third
means for joining the second end of the second section to the
needle comprise frictional engagements.
[0043] The frictional engagements include a hollow inner portion
(19) in the second section (15) having exterior openings (71) at
the proximal (16) and distal (17) ends. The hollow inner portion
(19) can extend the entire length of the second section (15) or
alternately, it can be limited to the ends (16, 17) of the second
section (15). The hollow portion (19) has an inner diameter that is
approximately equal to the outer diameter of the first (12) and
second (13) ends of the first section (11) and also that is
approximately equal to the outer diameter of the attaching end (73)
of the needle (20).
[0044] The exterior openings (71) of the hollow inner portion (19)
on the proximal end (16) of the second section (15) receives the
first end (12) therein, while the exterior opening (71) of the
hollow inner portion (19) on the distal end (17) receives the
second end (13) of the first section and, alternately, the
attaching end (73) of the needle (20). When the ends (12, 13) of
the first section (11) are inserted through the exterior openings
(71) into the hollow inner portion (19), a frictional engagement is
created between the respective inner and outer diameters which
secures the ends of the sections (11, 15) together. Likewise, when
the attaching end (73) of the needle (20) is inserted through the
exterior opening (71) into the hollow inner portion (19) of the
distal end (17), the needle (20) is held within the hollow inner
portion (19) by frictional engagement.
[0045] Although the first means for joining the second end of the
first section to the distal end of the second section, the second
means for joining the first end of the first section to the
proximal end of the second section, and the third means for joining
the second end of the second section to the needle comprise
frictional engagements, any suitable and separate types of means
could be used instead.
[0046] The first (11) and second (15) sections are elongated. In
one preferred embodiment, the first section (11) has a bow or bend
(70) in the center region. The bow (70) is offset approximately 1.0
mm from a reference plane in which the first (12) and second (13)
ends are located. In another preferred embodiment, the first
section of the ring is straight and does not have a bow.
[0047] The first section (11) is made from a substantially rigid
material. It is preferable that the material is able to maintain
its rigidity indefinitely and also preferable that it is inert or
compatible with body tissues. Examples of materials that could be
used for the first section (11) are titanium, stainless steel,
pyrolytic carbon and various plastics. Also, other suitable
materials of choice could be used, as well.
[0048] The material comprising the second section (15) is flexible
and is capability of being affixed to the first section.
Preferably, the material is inert or compatible with body tissues.
Examples of materials that could be used for the second section
include silastic, polyethylene, Dacron and Teflon. Also, other
suitable materials of choice could be used, as well.
[0049] The annuloplasty ring (10) of the present invention
reestablishes the normal shape and contour to the mitral valve
annulus (34). The first section (11) of the annuloplasty ring (10)
is adjacent to the inter-trigone section (36) after implantation,
as shown in FIGS. 1A-1F. The curvature of the bow (70) is oriented
to conform to the portion of the mitral valve annulus (34) that is
located adjacent to the aortic valve root. Both the first section
(11) and the inter-trigone section (36) are substantially rigid.
Since the inter-trigone section (36) does not normally bend in
response to the movements of the heart, it is, therefore, not
required for the first section (11) to bend or flex either.
[0050] The second section (15) is implanted adjacent to the
posterior portion (35) of the annulus. Both the posterior portion
(35) and the second section (15) are flexible and, as a result, can
flex and move with the natural movements of the heart, as the left
ventricle relaxes and contracts. Furthermore, the method of
implanting the annuloplasty ring within the fat pad (40) of the
atrioventricular groove (39), as shown in FIG. 4, ensures that the
annulus and the second section (15) of the ring (10) will remain
flexible indefinitely.
[0051] Referring again to FIGS. 1A-1F, the needle (20) acts as a
leader guide to implant the ring (10) in the proper location and
position in the atrioventricular groove (39) around the mitral
valve annulus (34). The tip (72) of the needle is preferably a
round-tip which is sharp enough to penetrate the tissue for
implantation, yet blunt enough to maneuver within the
atrioventricular groove without damaging critical areas.
[0052] The size and shape of the annuloplasty ring (10) can be
adjusted. Using the measurement indicia (18) on the second section
(15) as a guide, the appropriate length of the section is
established, then any unnecessary length on the second section (15)
can be removed by cutting, as shown in FIG. 1D. By changing the
length of the second section (15), the circumference of the
annuloplasty ring is also changed.
[0053] As shown in FIG. 2A, the second means for joining the first
end of the first section to the proximal end of the second section
and the first means for joining the second end of the first section
to the distal end of the second section secures the ends (12, 13)
of the first section (11) to the respective ends (16, 17) of the
second section (15) to form a closed loop. In one preferred
embodiment in which the first and second means for joining comprise
frictional engagements, the proximal (16) and distal (17) ends of
the second section are preferably disposed adjacent to each other
at a center region of the first section (11), thereby covering a
substantial portion of the first section (11). Alternately, the
second end (13) of the first section (11) can be free and
unattached while the distal end (17) of the second section (15) is
attached to the needle (20) for performing the annuloplasty as
shown in FIG. 5.
[0054] The length of the first section (11) is shorter than the
length of the second section (15). The length of first section (11)
can vary, but it is preferred that its length be no more than about
50-75% of the length of the inter-trigone section (36) of the
mitral valve annulus being repaired. The requisite proportion for a
particular annuloplasty ring will depend on the flexibility of the
second section (15). As for example, the more flexible the material
forming the second section (15), the longer the length of the first
section (11) should be relative to the length of the inter-trigone
section (36). Conversely, the less flexible the material of the
second section (15), the shorter the relative length of the first
section (11) should be relative to the length of the inter-trigone
portion (36).
[0055] The lengths of the two sections can be varied relative to
each other in order to achieve various shapes for the closed loop
of the annuloplasty ring (10). For example, by lengthening the
first section (11) relative to the length of the second section
(15), the annuloplasty ring will become "flatter" as characterized
by a smaller anterior to posterior distance.
[0056] In one preferred embodiment of the present invention, the
first section (11) has a length of approximately 1.5 cm and an
overall diameter of approximately 6 mm. The diameter can, however,
vary so long as it fits the mitral valve annulus under repair and
it precludes inadvertent deformation or breakage of the ring.
[0057] In one preferred embodiment, the indicia (18) are markings
spaced at intervals of about 1.0 mm. However, the intervals could
be spaced at any desired distance, extending for any desired length
along the second section (15).
[0058] An open configuration of the annuloplasty ring (10) is shown
in FIG. 6 wherein the first section (11) has its first end (12)
attached to the second section's proximal end (16). The second end
(13) of the first section (11) and the distal end (17) of the
second section (15) are unattached.
[0059] A closed configuration, shown in FIG. 2A, comprises the
first end (12) of the first section (11) being attached to the
proximal end (16) of the second section (15) and the second end
(13) of the first section (11) being attached to the distal end
(17) of the second section (15). In the closed configuration, the
annuloplasty ring (10) forms the closed loop. After the
annuloplasty procedure, the ring (10) is in its closed
configuration.
[0060] In FIG. 5, the annuloplasty ring (10) of the present
invention is shown in a surgical configuration in which the first
end (12) of the first section (11) is attached to the proximal end
(16) of the second section (15) and the needle (20) is attached to
the distal end (17) of the second section (15). The second end (13)
of the first section (11) is unattached. The surgical configuration
is designated primarily for use during the annuloplasty
procedure.
[0061] After the annuloplasty ring (10) is implanted as in FIG. 1E,
the first section (11) is in alignment with the inter-trigone
section (36) of the mitral valve annulus (34) such that the bow
(70) conforms to the contour of the annulus (34) adjacent to the
aortic valve root. The inter-trigone section (36) which extends
between the left (38) and right (37) fibrous trigones is
substantially rigid, as is the first section (11) of the ring. The
second section (15) is primarily implanted around the posterior
portion (35) of the annulus (34) and within the fat pad (40) of the
atrioventricular groove (39) as shown in FIG. 4. Along with the
posterior portion (35) of the annulus (34), the second section (15)
is allowed to move and flex freely with the movements of the
heart.
[0062] Referring to FIGS. 1A-1E, the annuloplasty ring (10) is
installed adjacent to the mitral valve annulus (34) and within the
fat pad (40) of the atrioventricular groove (39). After the ring
(10) is implanted, the second section (15) is cut to the
appropriate size for the patient. The distal end (17) of the second
section (15) is then attached to the first section (11).
Preferably, the ring (10) is sutured to the annulus at the left and
right fibrous trigones. However, this suturing may be avoided if
deemed not necessary.
[0063] To implant the annuloplasty ring in a patient, the needle
(20) is attached to the distal end (17) of the second section (15)
and the first end (12) of the first section (11) is attached to the
proximal end (16) of the second section (15), as shown in the
surgical configuration of FIG. 5. In one preferred embodiment, the
needle is attached by inserting its attaching end (73) into the
exterior opening (71) of the hollow inner portion (19) of the
second section (15).
[0064] The tip of the needle (20) is passed through the endocardium
(65) and the left atrial myocardial wall (46) from the endocardial
aspect at the right fibrous trigone (37), as shown in FIG. 1A,
simultaneously pulling the first (11) and second (15) sections of
the ring (10) behind it, such that a portion of the second section
(15) eventually passes through the left atrial myocardial wall (46)
as in FIG. 1B. The needle (20) is passed in a posterior direction
just external to and parallel to the mitral valve annulus (34). The
tip of the needle (20) is passed around the outside curvature of
the mitral valve annulus (34) and within the fat pad (40) of the
atrioventricular groove (39). The needle (20) is moved in a
clockwise direction towards the left fibrous trigone (38).
[0065] At the left fibrous trigone (38), the needle's tip (72) is
passed back through the left atrial myocardial wall (46) from the
epicardium (60) and back through the endocardium (65) at the left
fibrous trigone (38), thereby pulling the first section (11) into
position along the anterior portion (36) and pulling the second
section (15) into position within the atrioventricular groove (39)
such that the second section (15) is adjacent to the posterior
portion (35) of the mitral valve annulus (34), as shown in FIG.
1C.
[0066] Referring to FIG. 1D, the annuloplasty ring (10) is sized
using the measurement indicia (18) to determine the appropriate
length of the second section (15) and hence the appropriate
circumference for the annuloplasty ring (10). The distal end (17)
can be cut to size, if required, by severing the second section
(15) at a selected location on the second section (15). The needle
(10) can be removed prior to sizing and/or cutting of the second
section (15) or, alternately, it can remain attached to the ring
(10) during sizing and/or cutting.
[0067] The distal end (17) of the second section (15) is then
joined to the second end (13) of the first section (11). In one
preferred embodiment as shown in FIG. 1E, the second end (13) and
distal end (17) are joined by frictional engagement wherein the
second end (13) of the first section (11) is inserted into the
hollow inner portion (19) of the second section, until the distal
(17) and proximal (16) ends of the second section (15) approach one
another approximate a center point on the first section (11).
[0068] In another embodiment of the method for implanting the
annuloplasty ring, the procedure is reversed in direction, wherein
the tip (72) of the needle (20) is first passed through the
endocardium (65) and the left atrial myocardial wall (46) from the
endocardial aspect at the left fibrous trigone (38) and passed in a
posterior direction substantially parallel to the annulus (34). The
needle (20) is moved in a counterclockwise direction around the
annulus (34) to the right fibrous trigone (37). Here, at the right
fibrous trigone (37), the needle's tip (72) is passed back through
the left atrial myocardial wall (46) from epicardium (60) and back
through the endocardium (65). The procedure then continues as the
above procedure is performed in the opposite, counterclockwise
direction.
[0069] After the annuloplasty ring is in place sutures (80, 81)
shown in FIG. 1F can be added to secure the annuloplasty ring to
the annulus. A plurality of sutures (80) can be used to fix the
ring (10) to the inter-trigone section (36), preferably at the left
and right fibrous trigones. Since the inter-trigone section (36) is
substantially rigid in the native mitral valve annulus, any
scarring that may result from these sutures (80) would not
substantially interfere with the normal flexing of the rest of the
annulus and movement of the left ventricle.
[0070] In addition, at least one suture (81) may be used to fix the
second section (15) within the atrioventricular groove (39) as an
added precaution for guarding against possible slippage of the ring
(10) after it is implanted. This suture (81) would preferably be
located near the midpoint of the second section (15).
[0071] The preferred embodiments of the present invention allow the
mitral valve annulus to maintain its normal flexure, which in turn
enables the left ventricle to move in a normal manner as it
contracts and relaxes. Furthermore, the method of implanting allows
the annuloplasty ring and the annulus, as well, to maintain
flexibility indefinitely after the annuloplasty, since it is not
necessary to secure the ring in place with a line of sutures
through the mitral valve annulus tissue of the posterior
portion.
[0072] The ring further reestablishes the normal shape and contour
of the mitral valve annulus which allows for effective coaptation
of the anterior and posterior leaflets of the valve. Additionally,
the size and shape of the ring can be adjusted making it easily
adaptable to different patients.
[0073] In one example, the annuloplasty ring of the present
invention can be manufactured using a flexible material that is
also elastic to comprise the second section. The elasticity of the
ring would accommodate the expansion of the mitral annulus during
relaxation of the left ventricle and accommodate contraction of the
annulus during contraction of the left ventricle. In other words,
the annulus would expand and contract, in addition to flexing, with
the expansion and contraction of the left ventricle.
[0074] In another example, the first (11) and second (15) sections
are joined integrally at the respective first (12) and proximal
(16) ends, wherein the first section remains substantially rigid
and the second section (15) remains flexible. The integral joining
of the two sections can be done by coextrusion, molding or other
suitable manufacturing techniques of choice.
[0075] Although the present invention has been described in
considerable detail with reference to certain preferred versions
thereof, other versions are possible. Therefore, the spirit and
scope of the appended claims should not be limited to the
description of the preferred versions contained herein.
* * * * *