Anatomy tricuspid valve DR NIKUNJ R SHEKHADA (MBBS,MS GEN SURG ,DNB CTS SR)

1. SURGICAL ANATOMY
TRICUSPID VALVE &PULMONARY VALVE & RVOT
BY DR NIKUNJ
(CTS RESIDENT STAR HOSPITAL)
(Coordinator:DR P.SATYENDRANATH PATHURI)
(9/7/18)

2. SURGICAL ANATOMY
TRICUSPID VALVE
• The tricuspid valve is part of a complex functional system that also includes the
right atrium, the right ventricle, and the pulmonary circulation.
• With the tricuspid valve exposed, the surgeon observes sequentially
• right atrial cavity,
• atrio-valvular junction,
• tricuspid leaflets, and
• subvalvular apparatus.

4. RIGHT ATRIAL CAVITY

5. RIGHT ATRIAL CAVITY
• The right atrium consists of a curved
posterior groove continuous with the
superior and inferior vena cavae, a flat
interatrial septum, a trabeculated dome,
and the tricuspid valve
• The posterior groove is a smooth wall
separated from the trabeculated dome by a
ridge of muscle, the crista terminalis (a),
that extends from the superior vena cava to
the inferior vena cava.
• The interatrial septum has a central shallow
depression, the fossa ovalis (b),
• and the orifice of the coronary sinus (c)
guarded by a valvelike fold, the thebesian
valve (d).
• Another valvelike fold, the Eustachian valve
(e), guards the anterior extremity of the
inferior vena cava.

6. • The tendon of Todaro (f) is a fibrous structure formed by an extension of both the
Eustachian and thebesian valves.
• This tendon in conjunction with the orifice of the coronary sinus and the base of
the septal leaflet of the tricuspid valve delineate the triangle of Koch.This triangle
helps the surgeon locate two important components of the conduction system:
• the atrioventricular node (g), at the base of the triangle, and
• the bundle of His (h), which extends towards the apex of the triangle.
• The bundle of His crosses the septal segment of the tri- cuspid annulus
approximately 5 mm from the anteroseptal commissure. At this point the bundle
pierces the membranous septum or bypasses it posteriorly to reach the crest of
the muscular septum, where it bifurcates into multiple branches

7. THE ATRIO-VALVULAR JUNCTION
• The junction between the right atrium and the tricuspid valve is usually well-
delineated by the change in color and structure at the junction.
• In pathological valves,
• The annulus fibrosus is not visible from an atrial view because it is deeper and 2
mm external to the hinge

8. ANNULUS FIBROSUS
• This characteristic has important surgical implications
• sutures passed only through the hinge would compromise the motion of the
leaflets and would not reach the resistant fibrous body of the annulus; on the
contrary, sutures placed 2 mm external to the hinge and oriented towards the
ventricle reach the fibrous body of the annulus and preserve the free motion of
the leaflets.

9. • The annulus is a heterogeneous, almost virtual, structure composed of intermixed
fibrotic and elastic fibers in continuity with the leaflet tissue, the atrium, and the
ventricle. The posteromedial fibrous trigone reinforces the tricuspid annulus in the
area of the anteroseptal commissure.

11. • From the anteroseptal commissure, four annular segments can be described in a clockwise
fashion.
• The aortic segment is defined as the portion of the annulus localized at the proximity of the
neighboring aortic root. This identification is critically important because inadvertent suture
placement in this area during annuloplasty may lead to aortic valve or sinus injury.
• The anterior segment corresponds to the right outflow tract. It attaches the remaining part
of the anterior leaflet and the anteroposterior commissural leaflet.
• The posteriorsegment attaches the posterior leaflet and the postero- septal commissural
leaflet.
• The septal segment corresponds to the septum and attaches the septal leaflet and the
adjacent anteroseptal commissural leaflet .

12. • The septal attachment of the tricuspid valve is at a lower level than the septal
attachment of the mitral valve .
• As a result, a portion of the interventricular septum, the membranous septum,
separates the left ventricle from the right atrium , a configuration that explains the left
ventricular to right atrial shunts seen in congenital malformations.

13. • The annulus has a “wave form” instead of a planar configuration because of the bulging of
the right outflow tract, the nonlinear anterior and septal segments, and the lower position
(towards the apex) of the attachment of the septal leaflet.
• The two lowest positions (apically located) of the wave form are the anteroseptal
commissure,
• where the anterior leaflet attachment overrides the attachment of the septal leaflet (a)
and the posteroseptal commissure (b).
• The highest position is the portion of the aortic segment that corresponds to the right
outflow tract (c).

14. ANNULUS
• The shape of the “annulus” varies throughout the cardiac cycle. During diastole, it
is grossly circular (a) with a transverse diameter barely larger than the anteroseptal
diameter. During systole, the atrio- valvular junction has an ovoid shape with the
transverse diameter significantly larger than the anteroseptal diameter (b)

15. • The concentric reduction of the tricuspid valve orifice during systole results from the
contraction of the right and the left ventricles and the bulging of the aortic root. The
contraction of the orifice is not uniform because of the following underlying structures: the
septum, the right ventricle, and the aorta.
• In addition to concentric deformation, the tricuspid annulus displays three-dimensional (3D)
deformation at the junction of its different segments as well as rotational movement with
anterior displacement of its anterior segment in relation to its septal segment (c).
• This results in a helicoidal shape with a 3- to 7-mm gap at the anteroseptal commissure.

17. THE LEAFLETS
• he tricuspid valve consists of three leaflets, which are the opening and closing
structures of the tricuspid orifice.
• The three leaflets of the tricuspid valve have different sizes and shapes. The
anterior leaflet is larger than the posterior leaflet, which is larger than the septal
leaflet

19. THE ANTERIOR LEAFLET
• The anterior leaflet has a
semicircular shape and is attached
to the right ventricle and the
posteromedial trigone.
• The free edge of the valve may
present an indentation.
• The height of the anterior leaflet
averages 25 mm.
• Two zones,
• The proximal zone, or atrial zone, is
regular, thin, and translucent.
• The distal zone, or zone of
coaptation, is slightly irregular and
thicker than the proximal zone

20. THE POSTERIOR LEAFLET
• The posterior leaflet, which has a
roughly trapezoidal shape,
• is slightly smaller than the anterior
leaflet. It is inserted on one third of
the circumference of the annulus.
• This leaflet is often subdivided into
two or three segments by one or
two indentations.
• These indentations, sup- ported by
numerous chordae, facilitate the
opening of the leaflet during
diastole,
• the posterior leaflet has both
proximal and coaptation zones.
•

21. THE SEPTAL LEAFLET
• The septal leaflet is slightly
smaller than the posterior
leaflet and roughly
semicircular.
• A slight angle is visible at the
midline of its attachment to
the septum, which causes a
helicoidal shape of the
annulus
• the septal leaflet consists of
proximal and distal zones.

22. THE COMMISSURES
• The commissures, which separate the anterior, posterior, and septal leaflets, have
two zones the atrial zone and the coaptation zone.
• The commissural leaflets consist of semilunar leaflet tissue inserted on the annulus
with a free edge attaching characteristic fanlike chordae. The commissural leaflets
establish continuity between the three main leaflets of the tricuspid valve and
ensure the competency of the tricuspid valve.
• Since the commissural area is occupied by commissural tissue, the separation
between the leaflets does not reach the tricuspid annulus, an anatomical feature
that must be kept in mind when performing a commissurotomy.
•

24. THE SUBVALVULAR APPARATUS
• The tricuspid valve is connected to the
ventricular cavity by a suspension system—the
subvalvular apparatus—that has the following
two functions:
• one function is to limit the extent of the
upward displacement of the leafletsduring
systole;
• the other is to facilitate the opening of these
leaflets during diastole.
• To achieve these two goals, the suspension
system consists of the following two structures
that have different physical characteristics:
• papillary muscles, with contractile properties,
and
• chordae tendineae, with elastic properties.

25. THE PAPILLARY MUSCLES
• The papillary muscles inserted on the ventricular wall.
• The anterior papillary muscle is usually dominant and implanted on the anterior wall of the
ventricle near the apex. Its attachment may present two or three separate muscular
formations. The morphology of the anterior papillary muscle is usually long and bulky with
single or multiple heads.
• The posterior papillary muscle is either a single or a double entity implanted on the
posterior ventricular wall.
• The septal group comprises several small papillary muscles implanted on the septum. One
of the muscles near the anteroseptal commissure is implanted on the conus.

26. • The chordae tendineae, the extend from the papillary muscles to the leaflets, similar to the
suspension system of a “parachute”.
• On average, 25 chordae insert into the tricuspid valve.
• Three types of chordae can be described depending upon their attachment on the leaflets
• Basal chordae, attached to the base
• Intermediary or secondary chordae, attached to the
ventricular side of the belly of the leaflets.
• Marginal chordae, attached to the free edge.

27. • The attachment of the intermediary chordae to the leaflets may be bifurcated or
trifurcated but the marginal chordae are usually single, originating from various
levels of the papillary muscles.
• The interval between two adjacent chordae at the free edge rarely measures more
than 3 mm. This distribution prevents the prolapse of the free edge during systole.
•

30. TRICUSPID VALVE FUNCTION

31. • Two anatomical structures
close to the annulus are at risk
during tricuspid valve surgery
• (1) the non–coronary sinus of
Valsalva, especially the
commis- sure between the
non–coronary and right
coronary leaf- lets of the aortic
valve (asterisk)
• (2) the bundle of His, which
crosses the septal leaflet
attachment 3 to 5 mm from
the anteroseptal commissure
and then either perfo- rates or
circumscribes the membranous
septum before it bifurcates
into two branches.

32. RVOT

34. RIGHT VENTRICLE
• INLET :the right ventricle has a large sinus portion that surrounds and supports a
tricuspid atrioventricular (AV) valve.
• APEX
• OUTLET:smaller infundibulum (outlet portion) that supports a semilunar valve.
• The inlet and outlet valves of the right ventricle are thus widely separated.
• The entire sinus portion of the right ventricle and most of the infundibulum (both
free wall and septum) are coarsely trabeculated.

35. • The septal surface of the right ventricle is divided into
• an inlet portion:The inlet portion of the ventricular septum surrounds and
supports the tricuspid valve.
• a trabecular portion (sometimes called the apical trabecular portion), that portion
with the coarse trabecular pattern typical of the right ventricle
• The outlet portion of the right ventricular aspect of the ventricular septum is
smooth but complex and has three components

36. THE OUTLET PORTION OF THE RIGHT VENTRICULAR ASPECT OF THE
VENTRICULAR SEPTUM
• A) infundibular (conal) septum :which separates the pulmonary from the aortic
and tricuspid valves. Only part of the infundibular septum is interventricular , and
in some malformations (e.g., double outlet right ventricle)
• It must be emphasized that the most distal cepha lad portion of the infundibular
septum is not, strictly speaking, part of the ventricular septum, because in the
normal heart, the pulmonary valve arises from the apex of a cone of muscle and
does not have a septal attachment.
•

37. • B)outlet portion of the septum is the anterior (superior) extension, or division, of
the trabecula septomarginalis (septal band).
• C) A third small, very anterior portion is a narrow extension superior to the
trabecular septum.

38. • Laterally to the right, the infundibular septum imperceptibly merges with the free right
ventricular wall imme-diately beyond its attachment to the membranous septum; at that
point, it can be called the parietal extension of the infundibular septum .
• The parietal band lies anterior to the right aortic sinus , partially overlying that portion of
the free wall of the right ventricle termed the ventriculoinfundibular fold. (crista
superventricularis)

39. • Medially and to the left, the infundibular septum merges with the trabecular
portion of the septum between the limbs of the particularly prominent smooth, Y-
shaped muscle bundle called the trabecula septomarginalis.
• The trabecula septomarginalis extends apically to become continuous with the
moderator band, a prominent trabeculation running from septum to free wall

40. • The papillary muscle arrangement supporting the three leaflets of the tricuspid
valve is different from that of the mitral valve in the left ventricle.
• In the case of the tricuspid valve, in addition to a single large anterior papillary
muscle attached to the anterior free wall that fuses with the moderator band,
there are multiple smaller posterior papillary muscles attached partly to the
posterior (inferior) free wall and partly to the septum,
• group of small septal papillary muscles.
• The lowermost of these small septal muscles attaches posterior to the trabecula
septomarginalis.
• uppermost, called the medial (conal) papillary muscle (muscle of Lancisi or muscle
of Luschka), to the posterior limb of the septal band.

41. PULMONARY VALVE
• Pulmonary valve structure is similar to that of the
aortic valve.
• The pulmonary valve normally has three cusps, with a
nodule at the midpoint of each free edge, and lunulae
and thin, crescent-shaped coaptive surfaces on both
sides of the nodules.
• The pocket behind each cusp is the sinus.
• Pulmonary valve cusps have been described by several
terminologies,
• usually named by their relationships to the aortic
valve: right, left, and anterior
• as suggested by Anderson, right facing, left facing,
and nonfacing) in relationship to the adjacent
commissure of each valve.

42. • Major differences from the aortic valve are
• (1) lighter construction of pulmonary valve cusps.
• (2) normal absence of coronary artery origins, and
• (3) normal lack of fibrous continuity with the anterior tricuspid valve leaflet.
Pulmonary valve cusps are supported entirely by freestanding musculature, having
no direct relationship with the ventricular septum. The pulmonary valve is lifted
away from the ventricular septum by the subpulmonary infundibulum

43. • The first septal branch of the left anterior descending coronary artery pierces
theventricular septum below the shortest part of the subpulmonary infundibulum.
The artery is protected by the subpulmonary infundibulum
•

44. THANK YOU