Download Ventricular Septal Defect - Echo ED: Diagnostic Medical


The fetal heart
› Fetal echocardiography
› Fetal Circulation
The 4 chamber view
 Left ventricular outflow tract
 Right ventricular outflow tract
 Arterial Septal Defects
 Ventricular Septal Defects
 Hypoplastic Right Heart
 Hypoplastic Left Heart

Transportation of the Great Arteries
 Truncus Arteriosus
 Double Outlet Right Ventricle
 Ectopia Cordis
 Cardiac Tumors
 Endocardial Cushion Defects
 Tetrology of Fallot
 Ebsteins’s Anomaly
 Ventricular Hypertrophy
 Cardiac Arrhythmias
 Pericardial Effusion
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The fetal heart occupies approximately
one third of the thoracic cavity.
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Fetal Echocardiography should be performed
with the assessment of fetal arrhythmias.
Whenever congenital heart disease or
chromosomal abnormalities is suspected the
examination should be considered. If any of
these are present, the patient should be
referred for fetal echocardiography at 18 to 24
weeks of gestation.
Fetal Risk Factors: extra cardiac abnormality;
chromosomal abnormality; fetal cardiac
arrhythmia; non-immune Hydrops; question of
cardiac anomaly on prior sonograms;
intrauterine growth restriction.
Maternal Risk Factors: family history of CHD;
teratogenic exposure; maternal disorders;
maternal infection; familial syndromes.
› It can detect structural heart
abnormalities such as:
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Septal defects, disproportionate chambers
Transportation of the great vessels
Fetal arrhythmias
Coartation of the aorta
Cardiomegaly
Focal masses
Pericardial effusion
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Normal cardiac study checklist:
› 4 chamber view, right ventricle has
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moderator band, left atria: can visualize
pulmonary veins, and between the atria you
must see the space for the foramen ovale
which closes after birth
RVOT – RV to pulmonary artery and the
bifurcation. T
LVOT – LV to the aorta, must show with and
without valve
Aortic arch with the 3 branches (brachiocephalic, left CCA, and the left subclavian
artery)
Pulmonary artery (bifurcation)
Ductal arch(Pulmonic arch) looks like golf
club, whereas the aortic arch has more of a
candy cane shape)
Oxygenated blood enters the fetus through
the umbilical vein
 The ductus venosus partially bypasses the
lever to send oxygen – rich blood to the
right ventricle
 The foramen ovale shunts some of the right
atrial blood directly into the left atrium
 The ductus arteriosus allows oxygen-rich
blood from the pulmonary artery into the
aortic arch to circulate throughout the fetus
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Ductus Venosus: In the fetus, the ductus
venosus shunts approximately half of the
blood flow of the umbilical vein directly
to the inferior vena cava. Thus, it allows
oxygenated blood from the placenta to
bypass the liver. In conjunction with the
other fetal shunts, the foramen ovale
and ductus arteriosus, it plays a critical
role in shunting oxygenated blood to the
fetal brain
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Foramen Ovale: a shunt from the right
atrium into the left atrium

Ductus Arteriosus: a shunt connecting
the pulmonary artery to the aortic arch.
It allows most of the blood from the right
ventricle to bypass the fetus's fluid-filled
lungs
 Blood
flow through the heart is
proportioned as follows:
› 60% of right atrial blood passes through
the foramen ovale, into the left atrium,
and into the systemic circulation.
› 40% of right atrial blood enters the right
ventricle:
 92% of main pulmonary artery volume bypasses the
lungs via the ductus arteriosus and into the system
circulation
 8% of the ventricular blood reaches the lungs
In addition to creating two-dimensional
pictures of the cardiovascular system, a
fetal echocardiogram can also produce
accurate assessment of the velocity of
blood and cardiac tissue at any arbitrary
point using pulsed or continuous wave
Doppler ultrasound.
 This allows assessment of cardiac valve
areas and function, any abnormal
communications between the left and right
side of the heart, any leaking of blood
through the valves (valvular regurgitation).
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Fetal Echocardiography is used to
diagnose fetal cardiovascular diseases. It
can provide a wealth of helpful
information, including the size and shape
of the heart, its pumping capacity and
the location and extent of any damage
to its tissues.

Heart
› A 4 chamber view should be visualized
› Includes the RA, LA, RV, and LV
› The rt. & lt. pulmonary vein, descending aorta, and
lungs may also be visualized
› The 4cv is the single most important
image of the fetal heart.
› Normal features are:
 Apex of heart points 45 degrees to left anterior
chest wall
 Ventricles approx. the same size (right can be
larger than left in pregnancy)
 Flap of foramen of ovale opens into left atrium
 Prominent moderator bands present in apex of
right ventricle
 Valves separate both atria from ventricles
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Normal orientation of the 4 chamber
heart view within the fetal chest: the
heart should take up 1/3 of the chest
cavity with the apex pointing to the left
chest wall.
 Left
ventricular outflow tract view
(LVOT)
› ID origin of aorta from the left ventricle
› Sagittal section shows aortic arch and its
branches
› ID the origin of pulmonary trunk from the
right ventricle
› Correct orientation of pulmonary trunk is
draping anterior to the aorta when seen
in cross section.
› Diameter of the pulmonary artery is 9%
larger than that of the aorta
Atrial Septal Defect (ASD)
 Any abnormal opening between the atria is
referred to as an atrial septal defect. ASDs
are associated with a variety of cardiac
and chromosomal abnormalities. Diagnosis
is difficult because of the normal patent
foramen ovale.
Sonographic findings:
 Relies on demonstration of echo dropout at
the level of atrial septum
 Since foramen ovale is normally open,
prenatal diagnosis is unlikely.
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Because of the high pressure in the left
ventricle (needed to pump the blood
around the body), blood is forced
through the holes in the septum (central
heart wall) when the ventricle contracts,
thus increasing the pressure in the right
ventricle.
This
increased
pressure
(pulmonary hypertension) results in
excess blood flow to the lungs.
ASD- Atrial septal defect
Any abnormal opening between the atria is
an ASD.
Hard to diagnosis because of the normal
patent foramen ovale.
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Ranks first in frequency of all cardiac
anomalies. Caused by incomplete
closure of interventricular foramen and
failure of the membranous part of IV
septum. VSDs are the most teratogenassociated fetal defect, and are
associated with other cardiac anomalies
50% of the time.
Sonographic findings:
 Demonstration of an opening between
the ventricles on 4 chamber view
 Bidirectional flow demonstrated with
color Doppler
 Larger defects are easier to diagnosis.
A ventricular septal defect (VSD) is a
defect in the ventricular septum, the wall
dividing the left and right ventricles of
the heart.
 Congenital VSDs are collectively the
most common congenital heart defects.
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Ventricular septal defect (VSD)
› Ranks first in frequency of all cardiac
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anomalies
Opening between the two ventricles
Commonly caused by a teratogenassociated fetal defect.
Associated with other cardiac anomalies
50% of the time.
Seen by demonstrating an opening
between the ventricles on a 4 chamber view
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Generally occurs secondary to
pulmonary atresia, with an intact
interventricular septum.
Sonographic findings:
 Absent or markedly small right ventricle
on 4 chamber view
 Absent or small pulmonary artery
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Hypoplastic right heart syndrome
› Absent or markedly small right ventricle on 4
chamber view
› Absent or small pulmonary trunk
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A small left ventricle results from decreased
blood flow into or out of the left ventricle.
The primary abnormalities include aortic
atresia, aortic stenosis (coartation of the
aorta is present in 80% of cases), and mitral
valve atresia.
Sonographic findings:
 Absent or markedly small left ventricle on 4
chamber view
 Hypoplastic or aortic mitral valve and aorta.
Hypoplastic left heart syndrome (also
known as HLHS), is a rare congenital
heart defect in which the left side of the
heart is severely underdeveloped.
 While many authorities believe the cause
of HLHS is unknown, recent research
indicates that HLHS may be due to
genetic factors.
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In babies with HLHS, the aorta and left ventricle
are very small, and the aortic and mitral valves
are either too small to allow sufficient blood
flow or are closed altogether. As blood returns
from the lungs to the left atrium, it must pass
through an atrial septal defect to the right side
of the heart.
In a healthy human, the left side of the heart
receives oxygen-rich blood from the lungs and
pumps it out to the rest of the body; with these
structures underdeveloped, they cannot
circulate blood to other organs, and the right
ventricle must pump blood to both the lungs,
as it would normally, and to the rest of the
body, a situation which cannot be sustained
for long.
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In cases of HLHS, the right side of the
heart often must pump blood to the
body through a patent ductus arteriosus.
As the ductus arteriosus usually closes
within eleven days after birth, blood flow
is severely restricted and eventually cut
off,
leading
to
dangerously
low
circulation and eventually to shock.
Hypoplastic left heart syndrome
› Absent or markedly small left ventricle on a
4 chamber view.
› Hypoplastic mitral valve and aorta
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Homework: Submit an image of a Large
VSD
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Homework: Submit an image of a True
positive large ASD
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Homework: Submit an image of a
Hypoplastic Right heart
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Homework: Submit an image of a
Hypoplastic Left Heart.
TGA
 The origin of the great vessels are transposed
so that the aorta arises from the right ventricle
and the pulmonary trunk arises from the left
ventricle. A variety of other cardiac anomalies
are associated with TGA.
Sonographic findings
 Correct right-left orientation is a MUST
 Images
of
outflow
tracts
demonstrate
anomalous origin of great arteries
 Difficult sonographic diagnosis
Transportation of the Great Arteries (TGA)
Once again,
 The origin of the great vessels are
transposed so that the aorta arises from
the right ventricle (instead of the left
ventricle) and the pulmonary trunk arises
from the left ventricle ( instead of the
right ventricle)
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A single large vessel arises from the base
of the heart. A VSD is usually present,
and 48% of fetuses have other
noncardiac anomalies.
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Both the pulmonary artery and the aorta
arise from the right ventricle. This defect
is associated with other cardiac defects,
maternal
diabetes,
and
maternal
alcohol consumption.
In ectopia cordis, all or part of heart is
located outside of chest cavity. It is
frequently associated with intra-cardiac
anomalies
and
omphalocele
in
Pentalogy of Cantrell.
Sonographic Findings:
 Small thorax
 Extension of soft tissue outside thoracic
cavity in which cardiac activity is noted.
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Cardiac tumors are rare, and include
rhabdomyomas,
cardiac
fibromas,
myxomas and teratomas. 30-78% of
patients with cardiac rhabdomyomas
have tuberous sclerosis. Prognosis
depends on the size, number and
location of the tumor(s), as well as
associated arrhythmias and anomalies.
Some other conditions that can be diagnosed using
ultrasound:
Endocardial Cushion Defects
› Atrial and ventricular septal defects resulting from failure of
the common AV orifice to separate into mitral and
tricuspid valves. Associated with an increased risk of
Trisomy 21.
Tetralogy of Fallot
› Consists of four anatomic abnormalities: Large VSD,
overriding aorta, pulmonary infundibular stenosis, right
ventricular hypertrophy.
Ebstein’s Anomaly
 Downward displacement of the septal and posterior
leaflets of the tricuspid valve
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Endocardial cushion defect is also called
atrioventricular septal defect (AVSD).
AVSD involves problems with the
structure of the heart. The heart normally
has 2 upper chambers (atria) and 2
lower chambers (ventricles). A normal
heart also has 2 heart valves (the
tricuspid and mitral valves) that separate
the upper and lower chambers.

In AVSD, there may be a large hole in the
center of the heart where the wall (septum)
joins the upper and lower chambers of the
heart. The tricuspid and mitral valves may
not be separate. Instead, there can be one
large valve between the upper and lower
chambers
of
the
heart
(common
atrioventricular valve). The large opening
in the center of the heart allows the
oxygen-rich (red) and the oxygen-poor
(blue) blood to mix. The heart pumps blood
in a way that is not efficient and becomes
enlarged.
An AVSD is the most common congenital
heart defect found in children with Down's
Syndrome, accounting for 50% of the total.
 In its complete form there is a hole in the
wall between the top chambers (atria) and
a hole in the wall between the bottom
chambers (ventricles), and one common
valve between the two atria and the two
ventricles. In the partial forms there may not
be a hole between the bottom chambers
(ventricles) or the mitral and tricuspid valves
may not be joined together, but either or
both
may
leak,
known
as
valve
incompetence.

The tetralogy of Fallot (TOF) is a congenital
heart defect which classically has four
anatomical components. It is the most
common cyanotic heart defect and the
most common cause of blue baby
syndrome.
 It was described in 1672 by Niels Stensen
and in 1888 by the French physician Etienne
Fallot, for whom it is named.
 As classically described, tetralogy of Fallot
involves four heart malformations which
present together:
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1.A ventricular septal defect (VSD): a hole
between the two bottom chambers
(ventricles) of the heart. The defect is
centered around the 'outlet septum', the
most superior aspect of the septum, and
in the majority of cases is single and
large. In some cases septal hypertrophy
can narrow the margins of the defect
2.Pulmonic stenosis: Right ventricular outflow
tract obstruction, a narrowing at (valvular
stenosis) or just below (infundibular stenosis)
the pulmonary valve. The stenosis is the
major cause of the malformations, with the
other associated malformations acting as
compensatory
mechanisms
to
the
pulmonic stenosis. The degree of stenosis
varies between individuals with TOF, and is
the primary determinant of symptoms and
severity. This malformation is infrequently
described as sub-pulmonary stenosis or
subpulmonary obstruction.
3.Overriding aorta: An aortic valve with
biventricular connection, that is, it is
connected to the right ventricle as well
as the left ventricle. The degree to which
the aorta is attached to the right
ventricle is called "override." The aortic
root can be displaced anteriorly or it can
override the septal defect, but it is still to
the right of the root of the pulmonary
artery. The degree of override is quite
variable, with 5-95% of the valve being
connected to the right ventricle.
4.Right ventricular hypertrophy: The right
ventricle is more muscular than normal,
causing a characteristic boot-shaped
appearance as seen by chest X-ray. Due
to the misarrangement of the external
ventricular septum, the right ventricular
wall increases in size to deal with the
increased obstruction to the right outflow
tract. This feature is now generally
agreed to be a secondary anomaly, as
the level of hypertrophy generally
increases with age.
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There is anatomic variation between the hearts of
individuals with tetralogy of Fallot. The degree of right
ventricular outflow tract obstruction varies between
patients and generally determines clinical symptoms
and disease progression.
Tetralogy of Fallot occurs in approximately 3 to 6 per
10,000 births and represents 5-7% of congenital heart
defects. Its cause is thought to be due to
environmental or genetic factors or a combination. It
is associated with chromosome 22 It occurs slightly
more often in males than in females.
Tetralogy of Fallot results in low oxygenation of blood
due to mixing of oxygenated and deoxygenated
blood in the left ventricle through the VSD and
preferential flow of both oxygenated and
deoxygenated blood from the ventricles through the
aorta because of obstruction to flow through the
pulmonary valve. This is known as a right-to-left shunt.
Tetralogy of Fallot
4 anatomic abnormalities
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Large VSD
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Overriding aorta
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Pulmonary stenosis
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Right ventricular hypertrophy
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Ebstein's anomaly is a congenital heart defect
in which the opening of the tricuspid valve is
displaced towards the apex of the right
ventricle of the heart.
This causes the right atrium to be large and
the anatomic right ventricle to be small in size.
There may be an increased risk of this
abnormality in infants of women taking lithium
during the first trimester of pregnancy
While Ebstein's anomaly is defined as the
congenital displacement of the tricuspid valve
towards the apex of the right ventricle, it is
often associated with other abnormalities
Ventricular hypertrophy
› In utero - hypertrophy is most commonly
associated with cardiac outlet obstruction
but may be associated with maternal
diabetes.
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In the first trimester, cardiac rates vary
with gestational age. Prior to six weeks
the rate is relatively slow, typically
between 100-115 BPM. After six weeks,
cardiac rate increases rapidly, and by
eight weeks is between 144-159 BPM.
After nine weeks the rate plateaus at
137-144 BPM.
Premature atrial and ventricular
contractions
 Premature
contractions are entirely
benign arrhythmias in most cases. Most
disappear in utero or in early neonatal
period.
Tachycardia
 Fetal tachycardia is a heart rate greater
than 180 BPM. Most have a good
prognosis, and are treated in utero with
various pharmacological agents.

Tachycardia refers to rapid beating of
the heart. By convention it defined as a
heart rate greater than 100 beats per
minute in adults. Tachycardia may be
normal, such as in exercise and stress, or
abnormal,
such
as
in
cardiac
arrhythmias. However, depending on the
mechanism of the tachycardia and the
health status of the person, tachycardia
may be harmful and require medical
treatment.
In
extreme
cases,
tachycardia can be life threatening
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Tachycardia can be harmful in three ways.
First, if the heart is pumping too fast for an
extended period of time it will change the
balance of oxygen and carbon dioxide in
the hemoglobin in the blood; this is normal
during exercise but when resting this is quite
dangerous. Second, when the heart beats
too rapidly, it may pump blood less
efficiently as there is less time for the
myocardium
to
relax
between
contractions. Third, the faster the heart
beats, the more oxygen and nutrients the
heart requires. This may leave patients
feeling out of breath or cause angina in
those suffering from ischemic heart disease
Bradycardia
 Fetal bradycardia is a prolonged heart
rate of less than or equal to 100 BPM.
Transient bradycardia can be related to
an increase in intrauterine pressure.
Below 80 BPM, bradycardia may be
associated with fetal asphyxia. Persistent
bradycardia may warrant early delivery.
Bradycardia, as applied to adult
medicine, is defined as a resting heart
rate of under 60 beats per minute,
though it is seldom symptomatic until the
rate drops below 50 beat/min.
 The term relative bradycardia is used to
explain a heart rate that, while not
technically below 60 beats per minute, is
considered too slow for the individual's
current medical condition.
.
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“Fluid around the heart" is an abnormal
accumulation of fluid in the pericardial cavity.
Because of the limited amount of space in the
pericardial cavity, fluid accumulation will lead
to an increased intrapericardial pressure and
this can negatively affect heart function. When
there is a pericardial effusion with enough
pressure to adversely affect heart function, this
is called cardiac tamponade. Pericardial
effusion usually results from a disturbed
equilibrium between the production and reabsorption of pericardial fluid, or from a
structural abnormality that allows fluid to enter
the pericardial cavity.
What are the indications for a fetal
echocardiogram? Include the abnormal
findings and the risk factors.
 What are the normal findings associated
with a four-chamber view?
 List the normal orientation of the fourchamber view within the fetal chest.
 Draw a normal four-chamber view.
 List the checklist of a normal fetal
cardiac study.

Define Aortopulmonary transportation.
 Define pulmonary atresia
 What is the corrected transposition of the
great vessels?
 Regarding Fetal cardiac arrhythmias:
give the rates for normal, slow, and fast.

1. A four chamber view of the fetal hart
demonstrates some important anatomic
features. Name as may as you can.
2. What is the purpose of the left ventricular
outflow tract view?
3. What is the purpose of the right
ventricular outflow tract view?
4. True or False. The ductus venosus
bypasses some of the oxygenated fetal
blood from the liver to the inferior vena
cava
5.
True or False. A normal opening
between the right and left atria shunts
fetal blood from the right to left heart, in
order to bypass the lungs and direct it to
the systemic circulation.
6. True or false. The opening between the
two atria of the hart is called the ductus
arteriosus.
7. True of false. The foramen ovale cannot
be seen sonographically on a four
chamber view of the heart.
8. Why is an atrial septal defect difficult to
diagnosis sonographically?
9. Which cardiac defect is the most
teratogen-associated fetal defect?
10. What is hypoplastic right heart
syndrome? How does it appear
sonographically?
11. What is hypoplastic left heart
syndrome? How does it appear
sonographically?
12. True or False. Transposition of the great
arteries (TGA) can be diagnosed with a
good four chamber view of the heart.
13. Define transposition of the great
arteries (TGA)
14. What is ectopia Cordis?
15. With what is ectopia cordis associated?