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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_3654_Библиотеки_им_академика_М_И_Перельмана
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Fig. 5.19 Unicuspid acommissural aortic valve. View of the aortic root
from above: the aortic valve is unicuspid and there is no commissure
(acommissural valve). Three short raphes are recognizable remnants of
the aborted commissures. A small, central orice is present
C. Frescura and G. Thiene
with stenosis, high risk of endocarditis, aortopathy because
of wall degenerate with dilation of the ascending aorta, valve
incompetence, and aortic dissection at risk of sudden death
(Table5.3).
Aortic stenosis of bicuspid aortic valve is the consequence
of calcic degeneration of the cusps (Fig.5.30), similar to
senile calcic aortic stenosis. The onset of calcication in
bicuspid valve occurs earlier and more severely than in a normal tricuspid aortic valve. More than the 30% of patients
with aortic stenosis, requiring surgical replacement of the
aortic valve, shows a bicuspid valve.
The bicuspid aortic valve represents a well-known risk
factor for infective endocarditis (see chapter on endocarditis), and antibiotic prophylaxis is recommended also for
minimal surgical or invasive procedures. Infective endocarditis involves the cusps, with disruption and vegetations, and
the valvular annulus, accounting for abscesses and aneurysms in the Valsalva sinuses. The vegetations are composed
of platelets, brin, inammatory cells, and microorganisms.
abc
Fig. 5.20 Aortic valve stenosis with hypoplastic, broelastic left ventricle. (a) View of the left cardiac chambers: a diminutive mitral valve
connects the left atrium with the hypoplastic left ventricle. (b) View of
the left ventricular outow tract: a dysplastic aortic valve is present.
Note the remarkable endocardial broelastosis. (c) Closeup of the same
specimen: the aortic cusps show multiple nodular myxoid
excrescences
5 Congenital Anomalies oftheCardiac Valves
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With time, aortopathy develops in nearly 50% of patients
with bicuspid aortic valve. The sinusal and tubular ascending
aorta show an aneurismal dilatation due to disruption of elastic bers of the tunica media with loss of wall elasticity
(Figs. 5.31, 5.32 and 5.33). At histology, the degenerative
disease affects the tunica media with noninammatory loss
of smooth muscle cells (medionecrosis), fragmentation of
the elastic bers, and increased extracellular ground substance in the lamellar units (cystic medionecrosis) (Fig.5.32).
Fig. 5.21 Bicuspid aortic valve. View of the outow tract of the left
ventricle and ascending aorta. The aortic valve shows two intact cusps
without raphe. The colored triangle delimitates the area of the membranous septum
Fig. 5.23 Bicuspid aortic
valve. (a) Anatomical view
from the left ventricle
showing a bicuspid aortic
valve with latero-lateral
(side-by-side) arrangement of
the aortic cusps. The coronary
arteries take origin from the
opposite sinuses. (b) The
arrow indicates the raphe in
the left coronary sinus of
Valsalva. The colored triangle
identies the membranous
septum
ab
Fig. 5.22 Bicuspid aortic valve. Anatomical specimen with bicuspid
aortic valve: the cusps are in anteroposterior position, and both the
coronary arteries take origin from the anterior sinuses of Valsalva. A
brous raphe is present inside the anterior sinus of Valsalva (arrow).
The colored triangle indicates the membranous septum
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C. Frescura and G. Thiene
ab
Fig. 5.24 Bicuspid aortic valve and cusps arrangement. (a) Schematic
representation of bicuspid valve. The aortic leaets may be located in
anteroposterior or latero-lateral position. In the former situation, both
the coronary arteries take origin from the anterior sinus of Valsalva,
Fig. 5.25 Bicuspid aortic valve with anteroposterior position of the
cusps. (a) Left ventricular outow tract with a bicuspid aortic valve: the
membranous septum is transilluminated and delineated by a colored
triangle. Both the coronary arteries take origin from the anterior aortic
sinus. (b) Schematic representation of a bicuspid aortic valve with
anteroposterior position of the cusps: note the location of the membra-
whereas in the latter the coronary arteries take origin from opposite
sinuses. (b) Anatomical view from above: a bicuspid, dysplastic aortic
valve is present with cusps in anteroposterior position and with both
coronary arteries originating from the anterior sinus of Valsalva
nous septum (white area), the brous continuity of the posterior aortic
cusp with the anterior mitral leaet, and the origin of both the coronary
arteries (white spots) from the anterior sinus of Valsalva. The dotted
line indicates the aortic raphe in the anterior aortic sinus. A anterior
aortic cusp; AML anterior mitral leaet; P posterior aortic cusp
NC
RC
R
Fig. 5.26 Development of bicuspid aortic valve and origin of the coronary arteries. (a) The normal aortic valve shows three cusps and the
origin of the right coronary artery from the right anterior aortic sinus
and of the left coronary artery from the left anterior aortic sinus. L, left
cusp; LC, left coronary artery; NC, not coronary cusp; R, right cusp;
RC, right coronary artery. (b) In the bicuspid valve with anteroposte-
rior position of the cusps, both the coronary arteries originate from the
LC
L
RC RC
P
LC
A
anterior sinus. The valve is the result of the embryonic fusion of anterior right and left cushions. A, anterior cusp; LC, left coronary artery;
P, posterior cusp¸ RC, right coronary artery. (c) In the bicuspid valve
with latero-lateral position of the cusps, the coronary arteries originate
from opposite sinuses. The bicuspid valve derives from the fusion of
right and posterior embryological cushions. L, left cusp; LC, left coro-
nary artery; R, right cusp; RC, right coronary artery
LC
L
R
5 Congenital Anomalies oftheCardiac Valves
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a
Fig. 5.27 Bicuspid aortic valve with aortic isthmic coarctation. (a) A
bicuspid aortic valve with intact ventricular septum and severe aortic
isthmic coarctation. Note the presence of diffuse and severe atheromatosis of the ascending aorta and the subocclusion of the left atheroscle-
Fig. 5.28 Bicuspid aortic
valve with ventricular septal
defect and aortic isthmic
coarctation. (a) View of the
left ventricular outow and
aorta: a bicuspid aortic valve
is associated with a large
perimembranous ventricular
septal defect (arrow). (b)
Aortic arch and descending
aorta of the same specimen:
the arrow indicates the site of
severe aortic isthmic
coarctation
a
b
rotic coronary artery (arrow). The patient died by rupture of
postcoarctation mycotic aneurysm. (b) Closeup of the same specimen
showing a coarctation of the aorta in the isthmic region and mycotic
aneurysm
b
Fig. 5.29 Bicuspid aortic
valve, isthmic coarctation,
and aortic dissection. (a)
Bicuspid aortic valve with an
intimal tear. (b) Severe aortic
isthmic coarctation
ab
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C. Frescura and G. Thiene
Table 5.3 Bicuspid aortic valve: complication in the natural history
• Aortic stenosis
• Infective endocarditis
• Dilatation of the ascending aorta (aortopathy)
• Aortic valve incompetence
• Aortic dissection
Fig. 5.30 Stenotic bicuspid
aortic valve by dystrophic
calcication. (a) Schematic
representation of bicuspid
aortic valve with calcic
degeneration. (b) Anatomical
specimen of a bicuspid valve
with calcic degeneration.
The cusps of the valve are in
anteroposterior position. Note
the raphe within the anterior
sinus of Valsalva
ab
The consequences of the aortic wall degeneration are aortic valve incompetence (Fig.5.33) and even aortic dissection
(Figs.5.34 and 5.35) with risk of sudden death.
Rare is the occurrence of a quadricuspid aortic valve
(Fig.5.36) that usually is the cause of aortic regurgitation.
Fig. 5.31 Aortopathy with
bicuspid aortic valve. (a) The
sinus portion of ascending
aorta appears dilated. (a) At
histology, the aortic wall
shows loss of lamellar units
and elastic ber disruption
(Weigert-Van Gieson stain)
ab
5 Congenital Anomalies oftheCardiac Valves
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abc
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Fig. 5.32 Degenerative pathology of the aortic wall tunica media in
bicuspid aortic valve. (a) Noninammatory loss of smooth muscle cells
(medionecrosis) (hematoxylin-eosin stain). (b) Fragmentation of the
Fig. 5.33 Aortopathy and
bicuspid aortic valve
incompetence. (a) Anatomical
view of the left ventricle and
ascending aorta: note a dilated
aorta and aortic annulus, due
to degenerative disease of the
aortic tunica media. The
aortic valve is bicuspid and
incompetent. (b) Histology of
the wall of the ascending
aorta showing loss of the
elastic bers in the tunica
media (Weigert-Van Gieson
stain)
a b
elastic bers (Weigert-Van Gieson stain). (c) Pools of basophilic ground
substance (cystic medial necrosis) (Alcian PAS stain)
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Fig. 5.34 Bicuspid aortic
valve and aortic dissection.
(a) Aorta and outow tract of
the left ventricle with bicuspid
aortic valve and dissection of
the ascending aorta. The
patient died at rest due to
cardiac tamponade by aortic
rupture. (b) Histology of the
wall of the ascending aorta
with severe elastic loss
(Weigert-Van Gieson stain)
C. Frescura and G. Thiene
Fig. 5.35 Bicuspid aortic
valve and aortic dissection.
(a) Outow of the left
ventricle and aorta: a bicuspid
aortic valve is present. Note
the dilatation of the ascending
aorta and the intimal tear just
above the sinotubular
junction. (b, c) Histology of
the aortic wall showing the
dissecting hematoma and
elastic fragmentation of the
tunica media (Weigert-Van
Gieson stain)
ab
c
5 Congenital Anomalies oftheCardiac Valves
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Fig. 5.36 Quadricuspid aortic valve. (a) Drawing of a quadricuspid
aortic valve. (b) Anatomical specimen: the valve consists of four dysplastic cusps. Usually, the valve is incompetent. Under the aortic valve,
The quadricuspid aortic valve may be an isolated anomaly or
may be associated with other cardiac malformations, including ventricular septal defect, discrete subaortic stenosis, and
supravalvular aortic stenosis.
Pulmonary Valve
The pulmonary valve can be stenotic in the presence of unicuspid, bicuspid, or tricuspid valve (Table5.4).
The unicuspid valve (Fig.5.37) is the most severe and fre-
quent form of pulmonary stenosis and consists of a single
membrane and small central orice.
In the bicuspid and tricuspid pulmonary valves (Figs.5.38
and 5.39), the stenosis is due to the dysplasia of the cusps.
Pulmonary valve stenosis may be isolated or associated
with tetralogy of Fallot.
a brous endocardial thickening is also present, due to chronic aortic
regurgitation. (c) Closeup of the (b)
Table 5.4 Pulmonary valve morphology
• Unicuspid pulmonary valve
• Bicuspid pulmonary valve
• Tricuspid pulmonary valve
• Quadricuspid pulmonary valve
The quadricuspid pulmonary valve (Fig.5.40) is rare and
usually a benign anomaly without clinical symptoms. Only
sporadic cases of quadricuspid pulmonary valve stenosis or
insufciency are reported.
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C. Frescura and G. Thiene
Fig. 5.37 Unicuspid
congenital pulmonary valve
stenosis. It is the most
frequent and severe form of
valve stenosis. (a) Schematic
representation: the pulmonary
valve shows a single cusp,
formed by a brous
membrane with a small
central orice. (b) Anatomical
specimen: the unicuspid
pulmonary valve shows a
central orice and tiny raphes
which indicate the site of
aborted commissures
Fig. 5.38 Bicuspid
pulmonary valve. (a) Diagram
of a bicuspid pulmonary
valve. It may show normally
functioning or broticdysplastic leaets with
stenosis. (b) The pulmonary
valve, anterior and to the left
of the aortic valve, shows two
thickened cusps
ab
ab
Fig. 5.39 Tricuspid, stenotic
pulmonary valve. (a) Diagram
of a slightly stenotic tricuspid
pulmonary valve: the mild
valvular stenosis is due to
thickened cusps. (b) Outow
of the right ventricle showing
a tricuspid pulmonary valve
with thickened cusps. Note
the post-stenotic dilatation of
the pulmonary artery
ab
5 Congenital Anomalies oftheCardiac Valves
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Fig. 5.40 Quadricuspid
pulmonary valve. (a)
Schematic representation. (b)
Anatomical specimen with
quadricuspid pulmonary
valve: all the four cusps are
thickened. A subvalvular
pulmonary stenosis is also
present, due to hypertrophy of
the trabecula septo-marginalis
and crista supraventricularis
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Polyvalvular Disease
nodular myxoid thickening, and the semilunar valve may
present also abnormalities in the number of cusps.
Congenital polyvalvular disease is a severe cardiac malformation, characterized by maldevelopment and dysfunction
of multiple cardiac valves with congenitally dysplastic features (Fig.5.41). The anomaly affects not only leaets but
also commissures, chordae tendineae, and papillary muscles.
The atrioventricular valve leaets appear redundant with
This malformation can be observed in otherwise normal
hearts or be associated with other cardiac defects, like ventricular septal defect, and with extracardiac malformations.
Cases with chromosomal anomalies are reported. A high
incidence of congenital polyvalvular disease is present in
patients with trisomy 18.
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