2. • INTRODUCTION
• TIMING OF FETAL ECHOCARDIOGRAPHY
• EQUIPMENT
• LATERALITY OF FETAL BODY AND IMAGE
ORIENTATION
• VISCEROATRIAL ARRANGEMENT(SITUS)
• CARDIAC POSITION AND AXIS ORIENTATION
• SEGMENTAL ANALYSIS
• ECHOCARDIOGRAPHIC PROJECTIONS
fetal echocardiography
3. • Malformations of the heart and arterial trunks
are the most common form of congenital
anomalies found in humans.
fetal echocardiography
4. • Prevalence of CHD in live born
Indian child
Total CHD at birth 130-
270,000/year
Critical CHD (requiring
intervention in infancy):
80,000
Critical CHD receiving
treatment is only 3.04%
CHD mortality as a fraction
of infant mortality: 3-17%
*Based on available data of CHD prevalence at birth In developed
countries and present birth rates in India
fetal echocardiography
5. • Importance in developing world
Limited resources to treat complex heart problems.
Relatively few centres in public sector offering
treatment for complex CHD.
Very limited infrastructure for transporting sick
neonates with critical CHDs which are correctable.
Early diagnosis is a solution for this
Antenatal Cardiac Diagnosis
fetal echocardiography
6. • The incidence of CHD is much higher in the fetal
population.
• A good number of fetuses with complex cardiac
anomalies succumb in the first trimester itself,
even before the cardiac anomaly is suspected;
• some parents opt for termination of pregnancy
after the diagnosis is made in the mid-trimester;
and some cardiac anomalies are progressive and
end in intrauterine death.
• Thus, the incidence quoted above may be only
the tip of the iceberg.
fetal echocardiography
7. • Fetal echocardiography, or the use of
ultrasonic technologies to evaluate the fetal
cardiovascular system, enables diagnosis of
structural heart defects, and offers a way to
observe complex physiological processes prior
to birth
fetal echocardiography
11. Indications for converting a routine scan into
fetal echocardiography
1. Chamber asymmetry
2. Altered cardiac axis
3. Altered position of the fetal heart
4. Enlarged fetal heart
5. Arrhythmia
fetal echocardiography
12. TIMING OF FETAL
ECHOCARDIOGRAPHY
• Fetal echocardiography is best performed between 18 and
22 weeks of gestation.
• After 30 weeks gestation,
the shadowing effects of the fetal ribs,
ratio of fetal body mass-to-amniotic fluid increases
so acquisition of images more difficult.
• Early maternal transabdominal or trans-vaginal scan at 11
to 14 weeks of gestation, in pt with Increased nuchal
translucency.
• In the first trimester (11–14 weeks), cardiac details may not
be elicited well, but the presence of a pulsatile ductus
venosus or tricuspid regurgitation can be a very strong
marker for cardiac and chromosomal anomalies.
fetal echocardiography
13. Equipment &Technical aspects
• High frequency transducers probes for
resolution and details
• Phased array transducers with fundamental
frequencies between 4 and 12 MHz are
generally used.
• Curvilinear probe with wider near-field of
view.
• High frequency transducers with a narrower
footprint
fetal echocardiography
14. • Low frequency transducers and harmonic
imaging ---3rd trimester and
• axial resolution of 1 mm or less
this is particularly important given the
small size of critical fetal cardiac structures.
• Frames rates of 80 to 100 Hz are frequently
needed to view important events occurring at
heart rates in excess of 140 beats per minute
fetal echocardiography
15. • Tissue Doppler imaging is useful in the
assessment of fetal arrhythmia.
• decreased persistence, and increased
compression.
• The system should have the ability to zoom the
image without causing deterioration of image
quality.
• A higher pulse repetition frequency (PRF) is
required for colour Doppler in the fetus as
compared to the settings used for routine
obstetric colour Doppler.
fetal echocardiography
16. Determining the laterality of fetal body
and image orientation
• Most common used method for assesing laterality is proposed
by cordes et all.
• It is effective when fetus is in transverse position
Procedure:
• Obtaining sagittal view of fetal body. Align transducer in long
axis of fetus (spine)
• Orient the transducer so that fetal head is on the right side of
observer on the screen
• Rotate the transducer 90* clockwise to obtain a transverse
view of fetal body
• Tranverse section thus aquired is caudocranial axis
fetal echocardiography
23. Visceroatrial arrangement(situs)
• To assess morphological arrangement of atria
• Appendages are most constant component of
atria
• LA appendage is tubular and hook shaped
with narrow junction with venous portion of
atrium
• Vestibular aspect of LA is smooth
• Pectinate muscle is restricted to appendage
fetal echocardiography
24. • RA appendage is triangular with broad
junction with venous portion of the atrium
• Vestibular aspect of RA contain pectinate
muscle
• There is close relationship between
arrangement of atria and position of
descending aorta and great veins at level of
diaphagm
fetal echocardiography
25. • Situs solitus
descending aorta is left to midnline
IVC to the right of midline
stomach to the left
portal sinus curves to the right
predominant liver lobe to the right
fetal echocardiography
29. Cardiac position and Axis orientation
• Cardiac position and axis can be assessed in
four chamber view
• In this view by tracing sagital and coronal
planes through centre of thorax four
quadrants are identified
• Lv and most of RV and anterior part of LA lie
in left anterior quadrant
fetal echocardiography
32. Axis orientation
• Axis of heart refer to its long axis
• Axis orientation is expressed as the angle between a
line aalong the ventricular septum ,directed towards
the cardiac apex and midline sagittal plane of thorax
• The normal cardiac axis is 45± 15°
• . Altered axis is often associated with outflow tract
anomalies
• Types
levocardia
Mesocardia
dextrocardia
fetal echocardiography
36. • Atria
• LA appendage is tubular
• Vestibular aspect of LA is smooth
• RA appendage is triangular
• Vestibular aspect of RA contain pectinate
muscle
fetal echocardiography
41. • Arterial trunk
• Differentiated by branching pattern
• Aorta –
coronaries arise from sinuses
run superiorly to form aortic arch and gives
origin to brachiocephalic vessels,CIA
• Pulmonary artery runs anteroposteriorly and
bifurcates in right & left PA
• Main PA connects to descending aorta via ductus
arteriosus
fetal echocardiography
43. • Atrioventricular connection
• Concordant: atrial chamber connected with
appropriate ventricle
• Discordant: atrium is connected with
morphologically inappropriate ventricle
• In isomerism morphologic RV is determined
by right and left hand topology(palm on septal
surface and thumb in inlet and fingers in
outlet of ventricle)
fetal echocardiography
50. Four chamber view
• Obtained from transverse plane of upper abdo
men by tracing IVC to RA and then cranial
angulation give 4 chamber view
• RV is more anterior with blunted apex
• LV is posterior with ellipsoidal shape
• LA most posterior and close to spine and
descending aorta
fetal echocardiography
51. • Four chamber view:
Symmetry of chambers
Atrial Septum and PFO
Ventricular Septum
Atrioventricular Valves
Ventricular function
Rhythm abnormalities
fetal echocardiography
54. • Abnormalities of four-chamber anatomy may characterize
certain forms of congenital heart disease
• In many cases, the primary structural abnormality of the heart
may be apparent in the view of the central fibrous body. Such
defects may include
Complete atrioventricular septal (canal) defect,
Hypoplastic left heart syndrome,
Hypoplastic right heart syndrome,
Ebstein malformation of the tricuspid valve, and
Various forms of single ventricle
fetal echocardiography
56. • Dimensions of heart
• CT circumference ratio
normal– mean value of 0.45at 17 weeks and
0.50 at term
• CT area ratio
normal 0.25-0.35 throughout pregnancy
fetal echocardiography
58. • Measurement
• Fractionalshortening= (EDD-ESD)/EDD
Normal value 34%
• End systolic and diastolic transverse diameters
of ventricles
• Thickness of IVS,LV,RV
• LA volume
• Mitral & tricuspid annulus diameter
fetal echocardiography
63. • Normal Doppler flow profile of tricuspid and
mitral valve :
• Similar
• Diastolic pattern with 2 peaks E and A
• 2 peaks merge with each other when heart
rate > 160-170 beats/min
• No backflow into atria during systole
fetal echocardiography
64. • E wave is smaller than A wave due to reduced
fetal ventricular compliance so ventricular filling
depend on regular atrial contraction( loss of sinus
rhythm lead to fetal cardiac compromise)
• E wave increases throughout gestation with valu
of 25cm/s at 16wks to 45cm/s at term for mitral
valve and 30cm/s and 50cm/s for tricuspid valve
• A is relatively constant during gestation with
45cm/s for mitral and 50cm/s for tricuspid
• E/A ratio 0.5 at 16wks and 1 near term
fetal echocardiography
66. • Colour flow mapping in normal fetus in 4
chamber view show equal and nonaliased
flow through the atrioventricular valve in
diastole .
• In systole no evidence of regurgitation across
AV valves.
fetal echocardiography
68. • Colour flow mapping of pulmonary veins
reflects variation in pressure in LA
• Systolic peak slightly higher than diastolic
peak with small atrial reversal
fetal echocardiography
70. • Cardiac rhythm
• By M-mode and pulse wave doppler
• M-mode method: atrial and ventricular wall
moventment is recorded at same time
in sinus rhythm atrial contraction preced
ventricular contraction
By PW doppler: by inflow and outflow pulse
doppler of LV
fetal echocardiography
73. 5 chamber view
• With cranial angulation from 4 chamber view give
5 chamber view
Structures seen are
• Aortic valve and its root
• Inflow ,trabecular and outflow of LV
• LA and RA
• Trabecular part of RV
• Two pulmonary veins
• SVC
fetal echocardiography
78. 3 vessel view
• Obtained by sliding the scanning plane cephalad from
four chamber view towards fetal upper mediastinum
• Significant lesions in ventricular outflow tracts show
abnormal 3 vessel view
• Normally:
• Pulmonary trunk is largest and anterior and left
• SVC is smallest and posterior and right
• Aorta is in between two
• Show oblique axis of PA and short axis of aorta and SVC
fetal echocardiography
81. • Ascending aorta is defined as small if its
diameter is equal or smaller than SVC
diameter
• Pulmonary artery is defined as small if its
diameter is equal or smaller than aorta
diameter
fetal echocardiography
85. Arch sidedness based on position of descending aorta
in relation to spine
fetal echocardiography
86. Arterial duct and aortic arch
transverse view
• From transverse view of aortic arch slight
caudal angulation to the left ,visualise arterial
duct and aortic arch
Normal morphology
• Aortic and ductal arches merges together into
descending aorta
• Ductal arch larger than aortic isthmus and
both lie on left side
fetal echocardiography
89. Aortic arch long axis view
• This view is obtained by parasagital plane with
angulation from right of sternum to left
shoulder
Normal morphology
• Aortic arch in long axis(candy cane
appearence)
• Cross section of RPA
• Isthmus is aortic segment between left
subclavian and aortic end of arterial duct
fetal echocardiography
93. colour flow mapping across aortic arch
Flow in aortic arch changes direction by 180* so
different segments of aorta are represented in
opposite colours
Doppler spectrum is monophasic wave but with
a diastolic forward flow due to diastolic recoil
of aortic ach and low placental resistance
fetal echocardiography
96. Arterial duct long axis view
• This view is obtained by parasagital plane with
angulation from left of sternum to left
shoulder
Normal morphology
• The section show superiorly the main PA
which split into inferior branch (left PA) and
superior branch(arterial duct)
fetal echocardiography
98. • Arterial ductal flow assessment by pulse wave
doppler
• Systolic anterograde flow < 50cm/s at 6 wks to
130-160cm/s at end of pregnancy
• Diastolic peak velocity 0 at early pregnancy to
30-40cm/s near term
• Diastolic wave is due to rebound of energy
potentially stored by walls of main PA which
produces further flow from PA to aorta
fetal echocardiography
101. Bicaval view
• Obtained by orienting the scan plane along
the true sagittal plane of fetal body
immediately to right of midline
Normal morphology
• Longitudinal section of SVC and IVC
• RA and RAA
• Cross section of RPA
fetal echocardiography
104. • Caval flow
• S wave –due to atrial suction produced by
movement of tricuspid valve plane in an base to
apex direction during ventricular systole
• D wave—in early diastole ,correspond to
reduction in atrial pressure due to AV valve
opening
• A wave –retrograde wave in late diastole due to
atrial contraction
• ratio between peak s and peak d wave is constant
with value of 1.8 + 0.2 through out gestation
fetal echocardiography
107. RV outflow view
• Slight left side rotation from sagittal plane
(from right hypochondrium to left shoulder)
Normal morphology
• Structures of right heart and crossection of
aortic root
fetal echocardiography
112. LV long axis view
• Plane that runs from left hypochondrium to right
shoulder
• Obtained by rotating transducer 90* from apical
4 chamber view and tilting towards right shoulder
• Useful in assessing inlet and outlet portions of LV
• Subarterial and anterior muscular VSD can be
seen
• Aortic override can be assessed in subortic vsd
fetal echocardiography
116. Pitfalls
• Some lesions such as minor VSDs may be missed.
• Progressive defects, such as a bicuspid aortic
valve, may not be diagnosed at 18–20 weeks of
gestation.
• Outflow tract anomalies may be missed.
• Maternal habitus and fetal lie may be limitations.
• Visualization of details may not be possible
before 18 weeks.
fetal echocardiography
117. Conclusion
• It may be difficult or time consuming to
perform a dedicated fetal echocardiogram on
all patients.
• Four-chamber view, the outflow tracts, and
the three-vessel view would be sufficient to
diagnose 80–85% of cardiac anomalies.
fetal echocardiography
