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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_3740_Библиотеки_им_академика_М_И_Перельмана
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F. C. Wells
Fig. 11.7 The incision into the left atrium below the interatrial groove, exposing the inside of the atrium and the mitral valve. A sucker is secured
in the left atrium to aspirate any returning blood
The Annulus
Once the mitral valve is exposed, it is advisable to place
interrupted sutures around the annulus (annuloplasty
sutures), from Trigone to Trigone, as a rst step. This pulls
the valve into an even plane and enhances the view of the
valve rendering the components of the valve in anatomical
proportion. The placement of the annuloplasty sutures is
very important. The needle should be at right angles to the
tissue and pass vertically downwards into the ventricular
muscle followed by a rotation of the wrist to bring the suture
out of the tissue in an even curve so as not to convert the
penetrating needle hole into a linear tear (Fig.11.8).
There is a wide choice of annuloplasty devices. The principal choices are between rigid and exible complete rings
or partial bands. The reasons for implanting annular support
are rst to reduce the orice area of the valve to ensure optimal coaptation and second to stabilise the atrioventricular
junction into the future. During the procedure, the presence
of the sutures under the weight of the restraining clips
reduces the orice by as much as 10%. On completion of the
Fig. 11.8 Note the angle of the needle to the tissue. Its entry should be
at 90° to the tissue
structural repair and testing the result by lling the ventricle
under tension, the resulting coaptation height can be visualised by marking the atrial margin of coaptation with a sterile
marking pen (Fig.11.9).
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a
b
a
b
Fig. 11.9 (a, b) The line of coaptation marked with sterile blue ink.
The tensioned valve has been marked at the coaptation margin to reveal
the depth and evenness of coaptation throughout the length of the
commissure
The choice of annuloplasty band size can then be based
upon the full surface area of the closed and tensioned valve
and not just the aortic leaet as proposed by some (Fig.11.10).
Atrioventricular dilation occurs along the free left ventricular portion of the valve orice and not the aorto-mitral cur-
Fig. 11.10 (a, b) The valve is tensioned so that the ascending aorta
proximal to the aortic clamp is tense and the band size is chosen based
on the full surface area of the tensioned valve
tain portion which does not stretch. Hence there is no
rationale for a complete ring. In addition, the base of the ventricle is mobile throughout the cardiac cycle hence inherent
exibility in the chosen band can be argued to be an advantage. A partial band must extend from Trigone to Trigone and
not commissure to commissure to ensure long-lasting prevention of annular re-expansion (Fig.11.11).
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Fig. 11.11 (a) Placement of annuloplasty sutures from Trigone to Trigone. (b) Flexible annuloplasty band secured in position
F. C. Wells
Leaet Techniques
mitral stenosis may result. This may only be detectable on
exercise.
Quadrangular Resection ofMural Leaet
Sliding Annuloplasty
This technique, rst popularised by Professor Alain
Carpentier involves a reduction of the mural annular circumference to compensate for the excised tissue (Figs.11.12 and
11.13). Imaginary radial lines are drawn from the centre of
the aorto-mitral curtain, either side of the prolapse and that
segment is excised. Sutures (1–3) are placed across the
resected portion and pulled outwards to re-oppose the annular edges, thereby shortening the annulus (see Figs. 11.11
and 11.2).
The exible annuloplasty band is then inserted and the
fully repaired valve nally tested.
This long-established procedure for mural leaet prolapse, stabilised with an annuloplasty ring, has stood the test
of time and remains a mainstay of mitral reconstructive surgery. The limitation of the procedure is the reduction in valve
opening area which can be signicant and if not appreciated
If, during a quadrangular resection, a larger leaet resection
is required, then the tension on the reattached leaet edges
will be too great. To surmount this, the annulus can be shortened in the region by this technique. After the quadrangular
resection has been done, each side of the mural leaet is
detached from the annulus; in other words, undermining the
leaets for 1–2cm. on either side. This length of annulus can
then be longitudinally plicated reducing this part of the circumference bringing the cut edges of the leaets back
together. The leaets can then be reattached to the annulus
and to each other (Fig.11.14).
The annuloplasty band, if one is used, can be held by the
tied annuloplasty sutures already through the annulus. If the
length of leaet undermining is long, almost to each end of
the commissures, then a band may not be necessary.
d
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Fig. 11.12 (a) Lines of
intended resection. (b)
Quadrangle of leaet tissue
excised with the base wider
than the leading edge. (c)
Annulus fully retracted and
the annuloplasty sutures
ligated. The divided leaet
edges are sutured with
interrupted or running 4′0′
Proline™
a
b
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Imaginary radial
lines from topcentre to annulus.
Excised portion
Resected magins
Annulus retracted at reseded margin
c
Retracted annulus closed with 2’0’
with ethibond sutures
Annuloplasty
sutures
Leaflet re-approxe
with 4 ‘O’proline
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F. C. Wells
a
Fig. 11.13 (a, b) The annulus is retracted for the annuloplasty. The retracted annulus has been closed and the leaet re-apposed
Triangular Resection
b
Cords will still arise from the edge of the leaets within
these indentations giving proof of their congenital origin.
Where the prolapsing segment of leaet is voluminous, with
a surface area that is greater than the distance between the
non-prolapsing portion, an alternative approach is a triangular resection. Here the base of the triangular resection is at
the leaet edge. The depth of the resection into the leaet
will be determined by the breadth of the prolapsing segment
(Figs.11.15 and 11.16).
With a voluminous leaet, this technique can work well,
however, if too much leaet is resected, the sutured leaet
can draw the edges of the segment away from the leaet segments on either side giving rise to a leak through the clefts.
This may be compensated for by a smaller size annuloplasty
band, however if there is a suspicion that this may be the case
then alternative methods will be better employed.
If there is a paucity of cords at the margin of the reconstructed leaet, then a Gore-Tex neo cord may be placed at
the apex of the repaired leaet and drawn down to the appropriate height. This procedure is a development of the original
imbrication technique described by Dwight McGoon [4].
The outward growth of the neo-leaets may be variable as
well, with excessive growth frequently found in the P2
region, but also (although somewhat less frequently) in other
parts of the mural leaet (Fig.11.18).
These tall leaets—often unsupported on each side as
result of the deep clefts—are vulnerable to high stress loading in systole, which may result in leaet prolapse. As these
portions frequently have cords that are widely separated, it is
common to nd prolapse of these areas in the absence of
chordal rupture. The depth of these portions of the mural
leaet is frequently equal to that of the aortic leaet. If this is
not considered and dealt with at operation, the placement of
an annuloplasty ring will bring about early contact between
the leaets in early systole, and the reverse folding of the
aortic leaet into the outow tract of the left ventricle in midto late systole, causing outow tract obstruction and mitral
regurgitation. This is referred to as abnormal systolic motion
of the anterior leaet or S.A.M. for short. There are ways to
prevent this as long as the surgeon is aware of the potential
problem; these are (1) reduction of the mural leaet height,
and (2) the placement of extremely short neo-cords pulling
Leaet Height Reduction
the leaet almost to the ventricular wall and the use of a large
annuloplasty band so as not to reduce the orice area more
The mitral valve leaets arise from cushions of tissue at the
atrioventricular junction whilst the heart is a tube in the early
foetus. These cushions grow into projections that become the
leaets. The junctions of the cushions form the clefts in the
leaets. If growth is retarded at those sights, then deep clefts
are left, frequently reaching to the annulus (Fig.11.17).
than is needed to produce leaet coaptation of 0.8 cm.
Excessive traction of the mural leaet into the ventricular
cavity turns the valve into a mono-leaet valve. Whilst this
may be effective, it is anti-physiological and may lead to
unnecessary extra strain on the aortic leaet which may give
rise to aortic leaet prolapse at a future time. It is my prefer-
undercut
d
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Fig. 11.14 (a–c) Sliding
annuloplasty. The edges of the
incised leaets are
undermined on each side and
the corresponding annulus
shortened by tying each of the
annuloplasty sutures. The
leaets are then reattached to
the annulus and to themselves
Lines of
a
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A
A: Aortic leaflet
b
c
Stay Suture
Leaflets
underwined
• Leaflet edges
apposed
• Annuloplasty
sutures tied
• Leaflet reattached
to annulus
• Annuloplasty ban
about to slide in to
place.
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resection
sutured together
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F. C. Wells
abc
Tr iangular resection
Area for resection
Leaflet with
Leaflet edges
Fig. 11.15 (a–g) The excess tissue to be resected is marked out and then removed. The cut edges are then sewn together, either with continuous
or interrupted sutures
ab
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Fig. 11.16 (a–d) Another example of a triangular resection
Fig. 11.17 A deep cleft in the mural leaet extending to the
annulus
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F. C. Wells
c
d
Fig. 11.18 (a–c) Disproportionately and excessively tall mural leaets. (d) 3-D echo modelling of the prolapsing segments (three different valves)
ence to reduce the height of the mural leaet to restore the
normal height ratio of one third of the height of the aortic
leaet and then to place an appropriately sized annuloplasty
band to optimise coaptation and permanently stabilise the
repair (Figs. 11.19, 11.20, 11.21, 11.22, 11.23, 11.24 and
11.25).
The excised portion should take the form of a blunted
trapezoid and not an oval. If an oval is excised when the leaflet is drawn back to the annulus, it will tend to open up any
cleft with the leaet portion next to it and cause a leak
between the edges. The trapezoidal resection leaves more tissue to abut the leaet next to it (Fig.11.26).
With the leaet reconstructed, it may be necessary to add
neo-Gore Tex™ cords (see later section) (Fig. 11.27). The
appropriately sized band is then placed from Trigone to
Trigone sizing it on the whole surface area of both leaets
with the valve tensioned by a full ventricle.
Fig. 11.19 The base of the leaet is incised with a knife. The incision
can be completed with scissors
Mural leaflet detachment from annulus
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Incised margin
P
2
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Fig. 11.20 The base of the leaet is incised with a knife. The incision
can be completed with scissors
P
1
Atrioventricular fat
P
3
Fig. 11.23 Fat can often be seen in the atrioventricular junction after
detachment
Fig. 11.21 The base of the leaet is incised with a knife. The incision
can be completed with scissors
Fig. 11.22 Fat can often be seen in the atrioventricular junction after
detachment
Fig. 11.24 The suture line is begun
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