tricuspid valve evaluation in pregnancy
TRANSCRIPT
DOPPLER EVALUATION OF BLOOD FLOW
THROUGH ANATOMICALLY NORMAL TRICUSPID
VALVE OF THE FETUS
• Tricuspid valve connects the right atrium and the right ventricle.
• It consists of 3 cusps; anterior, posterior and septal leaflets.
• The anterior, also called the infundibular or anterosuperior, leaflet is typically the largest.
• The posterior leaflet is also referred to as the inferior or marginal leaflet and the septal leaflet is also referred to as the medial leaflet.
• Terminating on the ventricular side of the tricuspid valve leaflets, the chordae tendinae are connected to three papillary muscles in the right ventricle. The anterior papillary muscle is usually the most prominent, with the moderator band terminating at its head.
ANATOMY AND DEVELOPEMENT
• The tricuspid valve is formed in
weeks 5-6 of embryonic
development.
• After the atrioventricular (AV)
endocardial cushions fuse, each
atrioventricular orifice is
surrounded by local proliferations
of mesenchymal tissue, from
which the AV valves form and are
attached to the ventricular wall
by muscular cords.
• Finally, muscular tissue in the
cords degenerates and is
replaced by dense connective
tissue.
1. Screening for aneuploidies
in the at 11-14 weeks.
2. Cases with intra-uterine
growth restriction.
3. During fetal
echocardiogram.
INDICATIONS FOR TRICUSPID VALVE
ASSESSMENT
NORMAL FLOW PATTERN IN THE TRICUSPID
VALVE
• It is viewed in the 4 chamber
view of the heart.
• This view is obtained by placing
the probe just above the
diaphragm.
• The heart is viewed at the level
of the crux , If imaging just below
this level, the coronary sinus is
seen, if imaging just above the
crux, the left ventricular outflow
tract comes into view.
• The most anterior chamber is the
right ventricle, connected by the
tricuspid valve to the right atrium.
• Unidirectional.
• Biphasic
1. E- Wave.
2. A-Wave.
• E wave corresponds to early diastole flow of blood by pressure gradient from right atrium to right ventricle.
• A wave corresponds to atrial contraction in late diastole to actively push blood from the atrium to the ventricle.
• As the fetus ages, the E wave
form increases in height,
representing an increase in
speed as blood enters the
ventricular chambers during the
early filling phase of diastole.
• The A wave form does not
increase in speed as the fetus
ages. This suggests that the
speed of blood resulting from
atrial contraction remains
unchanged, irrespective of the
age of the fetus.
CHANGES IN E AND A WAVES THROUGHOUT
GESTATION
TEMPORAL RELATIONSHIP OF FLOW IN
TRICUSPID VALVE AND DUCTUS VENOSUS
ASSESSMENT OF ANEUPLOIDY
DURING FIRST TRIMESTER SCAN
• The gestational period must
be 11 to 13+6 weeks
• A four-chamber view of the
fetal heart should be
obtained
• A pulsed-wave Doppler
sample volume of 2.0 to 3.0
mm should be positioned
across the tricuspid valve
PROTOCOL FOR THE ASSESSMENT OF FETAL
TRICUSPID FLOW
• It should be kept in
mind that not all of the
leaflets of the TCV are
necessarily
incompetent. Therefore,
at least three Doppler
evaluations should be
obtained.
POINTS TO REMEMBER
• Tricuspid regurgitation
is diagnosed if it is
found during at least
half of the systole and
with a velocity of over
60 cm/s, since aortic or
pulmonary arterial
blood flow at this
gestation can produce a
maximum velocity of 50
cm/s.
A] Doppler flow profile in the
tricuspid valve with no
regurgitation during systole
B]Regurgitation during
approximately half of systole and
with a velocity more than 60 cm/s
C] The short reverse generated
by closure of the valve cusp
D] Jet produced by aortic or
pulmonary arterial blood flow,
which at this gestation can
produce a maximum velocity of
50 cm/s
11-14 week scan:
• 55% of cases of trisomy 21
• 30% of cases of trisomy 18
• 30% in cases of trisomy 13.
• 38% in cases of monosmy X
Other ultrasonographic markers
must also be evaluated for complete
risk assessment.
SIGNIFICANCE OF TRICUSPID VALVE REGURGE
AT 11-14 WEEKS
REGURGITATION IN ANATOMICALLY NORMAL
HEART WITH NO OTHER MARKERS OF
ANEUPOLIDY
1. increased preload [e.g. congestive
heart failure]
2. Increased afterload [e.g. pre-
eclampsia or indomethacin exposure]
3. Myocardial impairment
4. Dysrhythmia.
In the majority of cases (92%) the
possible cause may be established. In
other cases (8%) there may be "idiopathic"
tricuspid valve regurgitation.
CAUSES
ASSESSMENT OF TRICUSPID VALVE IN CASES
OF INTRAUTERINE GROWTH RESTRICTION
• E/A ratio is higher than normal fetuses of similar gestational age.
• This is due to preload impairment [not enough blood supply reaches the fetal circulation] without impairment in fetal myocardial diastolic function.
•
THANK YOU