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F. C. Wells
the problem will vary from valve to valve and many lesions
will be concealed by echo drop out pre-operatively.
Therefore, these cases should be undertaken by experienced
mitral valve surgeons.
References
1. Lillehei CW, Levy MJ, Bonnabeau RC Jr. Mitral valve replacement
with preservation of the papillary muscles and chordae tendinae. J
Thorac Cardiovasc Surg. 1964;47:532–43.
2. Silaschi M, Chaubey S, Aldalati O, etal. Is mitral valve repair superior to mitral valve replacement in elderly patients? Comparison of
short- and long-term outcomes in a propensity matched cohort. J
Am Heart Assoc. 2016;5:e003605.
3. Carpentier A. Cardiac valve surgery: “the French correction”. J
Thorac Cardiovasc Surg. 1983;86:323–37.
4. McGoon DC.Repair of mitral insufciency due to ruptured chordae
tendineae. J Thorac Cardiovasc Surg. 1960;39:357–62.
5. Aleri O, etal. The double orice technique in mitral valve repair:
a simple solution for complex problems. J Thorac Cardiovasc Surg.
2001;122(4):674–81.
Surgery ofRheumatic Mitral Valve
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Disease
FrancisC.Wells
12
Rheumatic valve disease resulting from repeated episodes of
untreated streptococcus A pharyngitis can present both early
and late. Almost one third of cases are asymptomatic and
there is no history of such disease in the acute phase resulting
in late presentation of mitral stenosis. In the early stage of
the disease, there is an acute inammation of the valve leaflets and often an accompanying myocarditis. Associated
with the myocardial inammation is ventricular dilatation
and along with that atrioventricular annular dilatation. Thus,
in the acute phase, mitral regurgitation may predominate. In
addition, in the acute phase there may be a polyarthritis/
polyarthralgia. This may be accompanied by subcutaneous
nodules, erythema marginatum, and choreoathetosis.
As the myocardial and leaet inammation regresses, it is
replaced by brosis of the valve leaets and the sub-valvar
apparatus and ventricular myocardial brosis. It is in this
phase that progressive mitral stenosis will develop. The subvalve apparatus thickens and contracts drawing the leaets
downwards. At the same time the leaets thicken and retract.
The mural leaet may fuse with the posterior ventricular
wall. At surgery, this situation can result in posterior wall
ventricular rupture if great care is not taken in mobilising/
removing this leaet tissue.
Children with early-stage rheumatic disease that present
with mixed mitral valve disease but predominantly regurgitation can usually be repaired. In the adult population where
presentation is late after the acute episodes, repair is still feasible in some cases. This of course is desirable in young
women who may wish to have children. Techniques for these
scenarios will be described.
Patients with severe calcied late presentation rheumatic
mitral stenosis will be best treated with mitral valve replacement. Even here, however, it is quite possible to retain most
if not all of the sub-valve connections either with the native
F. C. Wells (*)
Royal Papworth Hospital, Cambridge University Group of
Hospitals, Cambridge, UK
e-mail: francis.wells@nhs.net
cords and papillary muscles or the use of Gore-Tex© to form
new cords. Dr. Lillehiei reported the importance of the preservation of these connections as early as 1964 [1].
Surgical Techniques
Mitral Valve Replacement withSub-Valve
Preservation
In more advanced cases where repair is not possible valve
replacement, or prosthetic valve insertion, as it is more accurately described, should be done.
As in all of cardiac surgery, optimal exposure and control
of cardiopulmonary bypass are paramount for success. As in
the culinary profession, a variety of “recipes” are available to
the surgeon for safe access and myocardial protection but
these are my personal preferences. My practice is to use cannulation of the ascending aorta at the distal ascending and
aortic arch junction for arterial return and cannulation of
both vena cava through the right atrium with the pipes
uncrossed. I use a left ventricular vent to assist drainage and
snare the cavae with narrow tape “snuggers” to ensure all
vena caval return passes through the cannulation pipes and
not around them. This ensures fullest drainage and prevents
the heart from warming. Gentle elevation of the tapes also
helps with exposure of the left atrium and hence the valve.
The systemic temperature is lowered to 32°C, and a continuous irrigation of the pericardium with cold saline at 4°C is
used to lower metabolic rate of the heart and the other organs.
The heart is arrested with antegrade cold cardioplegia
repeated at 20-min intervals throughout the procedure.
The left atrium is usually entered through the atrioventricular groove. A self-retaining retractor is then introduced
to expose the valve. A proline stitch through the inferior margin of the incised left atrial wall which incorporates a pump
sucker allows better vision.
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2023
F. C. Wells (ed.), Atlas of Cardiac Surgery, Springer Surgery Atlas Series, https://doi.org/10.1007/978-3-031-43195-1_12
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Fig. 12.1 Atrial retractor in place and the whole valve easily seen. (a) Barlowe’s valve. (b) Rheumatic mitral stenosis
This set up will give excellent exposure for the vast majority of cases. Properly accomplished each of these moves will
optimise the view (Fig.12.1).
F. C. Wells
Valve Replacement (Insertion)
As a result of the brotic distortion of the valve, a strong grip
on the valve can be obtained by passing a strong stitch
through the body of the aortic leaet. By pulling this towards
the operator, the junction between the leaet (often very
thick and sometimes calcied) and the aorto-mitral curtain
can be seen. The leaet is then incised with an 11-blade knife
at the apogee of the leaet and the incision extended for a
centimetre or so in each direction (Fig.12.2).
At this point, the first valve retention stitch is placed at
the centre of the incision from the ventricular side. The
incision is then extended a further centimetre or so in
each direction and further sutures placed. When whole of
the aortic leaflet has been mobilised in this fashion, the
aortic leaflet is divided in its centre between each of the
sets of cords rom each papillary muscle head. The excess
leaflet at the apices is resected, and the next sutures are
placed through the residual leaflet and then through the
annulus pinning the sub-valve apparatus to the underside
of the annulus (Fig.12.3).
Next the mural leaet is detached and divided in its middle between the two sets of cards as with the aortic leaet.
Any excess tissue is resected, and the remainder with the
cords attached pinned to the underside of the annulus with
the valve sutures. By doing this it can often allow a valve
one size bigger than would otherwise be possible. In less
brotic valves with very little leaet tissue, the leaet can
just be gathered up in the stitch without detaching it
(Figs.12.4 and 12.5).
Fig. 12.2 The suture in the aortic leaet is pulling the leaet down to
assist the rst incision at the annulus
Valve Orientation
With tissue valves it is important to prevent the stent posts
from lying in the left ventricular outow as this can produce
a high gradient across the aortic outow tract. To achieve
this, each strut should coincide with the trigones of the mitral
annulus.
Annular Decalcication
Frequently in more elderly patients with chronic rheumatic
mitral stenosis, the annulus and the leaets calcify, sometimes very extensively (Fig.12.6).
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Fig. 12.3 The triangular apices of the detached and divided aortic leaflet are resected
91
Left in situ this dense calcication can make valve insertion extremely difcult. However with some experience and
great care it can be excised allowing the insertion of a larger
prosthetic valve (Fig.12.7).
Once removed the atrioventricular connection should be
re-established with a generous pericardial patch sewn with
the lower ventricular margin well below the lower margin of
the resection with sutures placed into the pristine ventricular
muscle. The upper border is sewn to the atrial wall. There
should be no tension on the patch (Fig.12.8).
Once this has been done, the new valve can be sewn into
place. Along the mural junction, the sutures can safely be
passed through the pericardium.
Mitral Valve Reconstruction inRheumatic
Disease
In children and young women, the use of a mechanical valve
which would be the valve of choice over a tissue valve in this
cohort is to be avoided if at all possible. The reason for this
a
Fig. 12.4 (a, b) The sutures passed through the detached mural leaet
b
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Fig. 12.5 The sutures are passed through the valve sewing ring which
is then lowered into position and the sutures tied
F. C. Wells
Fig. 12.7 Showing sharp dissection and removal of an extensive bar of
calcium from the annuls. The yellow fat of the atrioventricular junction
can be seen
Mural leaflet
Fig. 12.6 Extensive annular calcication of the mitral valve
Calcified bar
Atrio
ventricular
fat
Detached mural
leaflet
Pericardium
Fig. 12.8 The mural leaet has been detached, the calcium removed
and the atrioventricular junction restored with a generous pericardial
patch
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Fig. 12.9 Insertion of
pericardial patch for mural
leaet extension
93
Mural leaflet
detached comm.
to comm.
Large native
pericardial patch
is that long-term warfarin therapy is extremely hazardous in
parts of the world where anticoagulant control is poor or
non-existent. In the relatively early stage of the disease in
children and young adults, reconstruction is often possible.
This consists of much more than simple commissurotomy
and the division of some restrictive cords.
If the aortic leaet is reasonably well preserved and the
majority of the pathology is in and around the mural leaet
and the mural annulus, reconstruction should always be
considered.
Tethering cords can be divided and/or replaced with
Gore-Tex sutures. A heavily retracted mural leaet can be
detached from the annulus and a generous pericardial patch
inserted to extend the leaet length. When done well, this
usually results in the leading edge with the cordal attachments becoming the coaptation surface extending down into
the ventricular cavity. The patch needs to be quadrangular in
shape and not oval and should extend from near commissure
to commissure. Similar extension of the aortic leaet can
also be achieved (Fig.12.9).
29 mm
Fused and shortened papillary muscle heads can be
incised and mobilised. The commissurotomy’s whilst being
generous should not extend to the annulus as this is likely to
leave new mitral valve regurgitant.
In many cases, the leaets have a brotic pannus over the
whole of their surface which can with care be peeled away
leaving a more exible leaet.
In all of these cases, stabilisation of the annular orice is
important and to achieve this a simple exible band extending from Trigone to Trigone excluding the aorto-mitral curtain region is sufcient. The band will be sized on the whole
surface area of the tensioned closed mitral valve and not
solely upon the anterior leaet.
Reference
1. Lillehei CW, Levy MJ, Bonnabeau RC Jr. Mitral valve replace-
ment with preservation of papillary muscles and chordae tendinae. J
Thorac Cardiovasc Surg. 1964;47:532–43.
Mitral Valve Infective Endocarditis
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NarainMoorjani
13
Mitral valve endocarditis represents an infection of one
or both mitral valve leaflets. Normal cardiac endothelium
is resistant to infection and even with transient bacteraemia, endogenous immune mechanisms, including thrombocidins (microbicidal proteins released by platelets),
help to prevent endocarditis. Patients with endothelial
disruption or non- laminar blood flow, such as those with
some degree of valve dysfunction (stenosis or regurgitation), however, are at risk of sterile platelet-fibrin thrombus formation. The Venturi effect usually causes the
thrombus to form on the low- pressure side of the turbulent blood flow, such as with mitral regurgitation on the
atrial side of the valve.
Subsequent bacteraemia allows colonisation of the preexisting thrombus, resulting in vegetation formation. The
bacteraemia can be induced by an invasive procedure, such
as dental extraction, endoscopy, or surgery in the presence
of infection. The organisms are able to multiply within the
platelet-brin thrombus and are ‘protected’ from the body’s
immune system. The most common organisms associated
with native valve endocarditis are bacteria, including
Streptococcus viridans, Staphylococcus aureus,
Staphylococcus epidermidis, and the enterococcus
Streptococcus faecalis. Amongst their properties, these
organisms are able to induce platelet aggregation, bind to
the surface of the brin-platelet thrombus, as they possess
bronectin receptors, and resist the bactericidal action of
complement and certain platelet proteins.
The pathological effects of infective endocarditis are
secondary to spread into the surrounding tissues causing
local tissue destruction, such as leaet perforation or periannular abscess formation. In addition, embolisation of the
vegetation can result in peripheral abscesses or infarcts,
such as cerebral, renal, or splenic. Peripheral effects of the
infective endocarditic process can also occur secondary to
immune complex deposition, such as vasculitis or
glomerulonephritis.
Echocardiographical Findings
Transthoracic echocardiographic images often reveal the
presence of a vegetation on the anterior or posterior mitral
valve leaets, associated with normal movement of both the
leaets, on both the apical and parasternal long- axis views
(Fig. 13.1), where the vegetation can be seen as a mobile
mass attached to the atrial surface of either leaet. Doppler
ow across the mitral valve may demonstrate a jet of mitral
regurgitation (MR), through a perforation in the one of the
leaets (Fig.13.1).
Trans-oesophageal echocardiographic images are often
used to conrm the presence of the vegetation on the leaets
and also demonstrate any extension of the infective process
into the surrounding structures, such as the mitral valve
annulus, aorto-mitral curtain, or aortic valve leaets
(Fig.13.2).
N. Moorjani (*)
Department of Cardiothoracic Surgery, Royal Papworth Hospital,
Cambridge, UK
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2023
F. C. Wells (ed.), Atlas of Cardiac Surgery, Springer Surgery Atlas Series, https://doi.org/10.1007/978-3-031-43195-1_13
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N. Moorjani
Fig. 13.1 Transthoracic echocardiographical images demonstrating a
0.7cm vegetation lying on the atrial side of the anterior mitral valve
leaet on apical (top left) and parasternal long-axis (top right) views,
associated with a jet of severe mitral regurgitation through the perforation on the corresponding parasternal long-axis colour ow Doppler
image (bottom)
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Fig. 13.2 Trans-oesophageal echocardiographical images demonstrating a 0.7cm vegetation on the atrial surface of the anterior mitral valve
leaet on mid-oesophageal long-axis (top left) and 4-chamber (top
right) views, associated with a jet of severe mitral regurgitation through
the perforation on the corresponding colour ow Doppler image (bot-
tom left), and a perforation visible in the body of the anterior leaet on
a 3D short-axis view (bottom right)
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N. Moorjani
Surgical Strategy
Although a proportion of patients with mitral valve infective
endocarditis can be treated medically with antibiotics, surgical intervention is often required and should be initiated
early to reduce the risk of on-going valve destruction or
embolisation. When operating on these patients, it is important to rst determine whether repair is feasible or replacement is necessary. Although mitral valve repair in this setting
may prolong the ischaemia time, there is evidence of both
short- and long-term advantages of repair over replacement,
including a lower incidence of recurrent endocarditis,
improved freedom from reoperation, and long-term survival
advantage in this patient cohort.
Indications forSurgery
1. Uncontrollable sepsis despite appropriate antibiotics for
an adequate time (7days)
2. Abscess formation in the annulus or leaets
3. Uncontrollable heart failure
4. Signicant embolisation from large vegetations on the
leading edge of the leaets
5. Any of the above in association with Staphylococcus
aureus infection
The timing of surgery needs to be carefully considered,
especially as early surgery in the presence of signicant ongoing infection runs the risk of recurrence of infection, particularly in the presence of an articial valve.
During the operation, it is important to avoid excessive
manipulation of the heart before the aortic cross-clamp has
been applied, to avoid systemic embolisation of infected tissue. The key principle in determining the feasibility of valve
repair in patients with mitral valve infective endocarditis is
to identify the lesions caused by the infective process and the
extent of tissue destruction. There are several patterns of
destruction encountered in these patients, including perforation of the anterior leaet, destruction of the posterior leaet,
commissural prolapse, and annular abscess. It is quite common to nd anterior leaet perforation in patients with concomitant endocarditis of the aortic valve, due to jet lesions
onto the aorto-mitral curtain and anterior leaet.
Leaet Reconstruction
In patients where the regurgitation is caused by leaet perforation, it is important to assess whether it is possible to
resect the infected tissue with a clear margin, whilst leaving enough native tissue to form a competent valve. The
mitral valve is assessed, using segmental analysis of the
leaets and the subvalvular apparatus, and correlated with
the trans- oesophageal echocardiographical ndings. Stay
sutures (5/0 prolene) are placed around the chordae tendineae attached on either side of the perforated area of the
affected leaet. Gentle traction on these stay sutures gives
better access and visualisation of the leaet. The vegetation and any residual infected leaet surrounding the perforation are excised and sent for microbiological analysis.
At this stage, it is important to assess the degree of destruction to the surrounding tissues and whether enough of the
valvular and subvalvular structures remained intact and
free from the infective process to produce a competent
valve by repair. If the valve is deemed repairable, all macroscopically infected and inamed tissue is excised to
ensure that the residual native tissue is free from infection,
with a 2mm margin. The residual tissue must be strong
enough to hold suture material.
Repair of a defect in the anterior leaet is usually possible, even if up to 50% of the leaet body is involved, so long
as the leading edge of the anterior leaet, along the coaptation line, is intact. The defect in the leaet body may be
repaired with fresh autologous pericardium, glutaraldehydetreated autologous pericardium, or bovine pericardium.
Bovine pericardium is used if autologous pericardium is not
available, such as in patients undergoing reoperation. Bovine
pericardium, as well as glutaraldehyde-treated autologous
pericardium, also has the advantage of being easier to handle
and are used for more complex reconstructions. Although
decellularised porcine intestinal submucosa (CorMatrix™)
has also been used for leaet patch augmentation, there have
been reports of patch dehiscence or tearing using this
material.
The pericardium is implanted using a continuous locking
5/0 prolene suture, to avoid purse-stringing the patch
(Figs.13.3 and 13.4). It is important to oversize the patch to
ensure that there is no tension on the leaet causing restricted
leaet motion. In some patients, additional Gore-Tex neochordae are required to support the free edge of the anterior
leaet.
Infective lesions of the posterior leaet can usually be
treated by resection, using the standard principles of triangular or quadrangular resection, with or without annular
plication and sliding plasty. In addition, some patients will
require patch augmentation or Gore-Tex neo-chordae to
support the leaet body and free edge, respectively
(Fig.13.5).
Infective destruction of the anterolateral or posteromedial
commissure, however, can be more difcult to treat.
Following resection of the infected adjacent segments, sliding plasty is often required to advance posterior leaet tissue
to reconstruct the commissure (Fig.13.6). Again additional
patch augmentation, Gore-Tex neo-chordae or annular plica-
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