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When a heart murmur is heard, a cardiac lesion is suspected. Some
tests must be done to detect and confirm the diagnosis. After the
diagnosis is confirmed, some lesions require interventions. The tests
done are:
1-Non-invasive tests
2-Invasive tests
Non-invasive:
Echocardiogram:
The echocardiogram, also called ultrasound of the heart, is the
mostly used test to confirm diagnosis. In this test, sound waves
are used to have a complete picture of the heart, its structure
as well as the movement of the blood in the heart. The child
should lie down on a bed and stay calm in order to have a clear
picture. Some gel is put on the child’s chest and the probe is
moved over the chest. This test is painless and has no side
effects. Parents can stay with their children during the test
which takes between 20 to 40 minutes.
Some children, especially the young ones, tend to be scared and
it is hard for them to stay calm. In this case, a sedation is
done using Chloral Hydrate. The child should be given the
sedation 30 minutes before the echocardiogram is done.
What to do before and after the sedation:
It is preferable for the child to be given the sedation on
an empty stomach. When the child has an appointment for an
echocardiogram, it would be recommended to stop breast milk
and/or infant formula 4 hours before, and to stop all kind of
food 3 hours before.
When the child sleeps, he will be ready to proceed with the
test. When the test is finished, the child and the parents must
stay until the child wakes up. The child should not be given any
food or drink immediately.
Fetal Echocardiogram:
A fetal echocardiogram is an ultrasound of the heart of the baby
while still in the womb. The test is done using the same machine and
the same technique as the regular echocardiogram. Sound waves are
used to give a picture of the structure of the heart and its blood
flow. To be able to have a clear picture of the baby’s heart the
gestational period should be at least 28 weeks, however, starting
from 18 weeks of gestation, a fetal echo can be done but the mother
will need to drink a lot of water before the test.
The test is done like a regular echocardiogram, some scanning gel
is used and the probe is passed on the mother' s abdomen. The test
may take some time to be able to locate the baby’s heart.
The test is safe, no side effects are associated to it and it
doesn’t produce radiation that could harm the baby or the mother.
EKG:
The EKG, also called ECG or electrocardiogram, is an essential
test done to study the heart. It studies the electrical activity of
the heart thus giving information about its rhythm. It can also
provide information about any enlargement of any of the four heart’s
chambers.
The test is done by placing some patches on the child’s chest
which are connected to the EKG machine. The machine will record the
heart rhythm. This test is painless and is done in few minutes.
There are no side effects. The child or the parent have nothing to
do to prepare for this test, it can be done at any moment.
Treadmill:
Some children might only encounter problems and symptoms upon
exercising. For this reason the exercise treadmill test is used. It
will see the ability of the heart to respond to exercise.
During this test, the child will be asked to walk on a treadmill.
All throughout the test, a machine will be monitoring the child’s
heart rate and blood pressure. The speed of the treadmill as well as
its inclination will start very small then will be increased every
three minutes to strengthen the activity level. After a certain
time, the child can run on the treadmill. The child will stop
whenever he is too tired or when any problem in the heart rate,
blood pressure or symptoms is noticed. However, the treadmill should
not be stopped completely at once. After the treadmill speed is
decreased, the child is asked to continue walking on the treadmill
for 10 minutes so that the heart rate and blood pressure can
normalize again.
The child should not eat a heavy meal before coming to the test
and should abstain from eating one hour prior to the test. The test
is painless.
Chest X Ray:
A Chest X – ray is a picture of the chest done by rays that are
emitted from a machine. In this picture we can have a clear view of
the heart, bones and blood vessels of the chest. The picture can be
taken either from the back to the front ( anteroposterior view) or
from one side to the other ( Lateral view).
The chest X-ray is important and used to determine the size of
the heart, to see whether heart has a normal size or is enlarged due
to increased blood flow and heart failure. The size of a chamber or
a blood vessel can also be known, whether there is enlargement or
not. A chest X-Ray can also give information about the blood flow to
the lungs. In some lesions the blood flow can be reduced whereas in
others it can be increased. By using a chest-X-ray we can determine
the blood flow.
The information given by a chest X-Ray is however less accurate
than the one given by an echocardiogram.
The chest X-Ray is painless and has no side effects.
Tilt test:
Some children have cases of fainting, also called syncope, that
can be due to non serious health problems like vasodepressor whereby
a sudden loss of pressure occurs when a person changes his or her
position and stands up, resulting in a low blood flow to the brain
and thus fainting. Sometimes, fainting occurs due to other more
serious and life-threatening reasons. The cause of the fainting and
thus the severity of the health problem should be studied.
The tilt test is used to determine the cause of fainting. For
this test, the child is lying on a bed and the bed is moved to an
upward position several times without any effort from the child. If
the child faints, the test is positive. A positive test means that
the reason for fainting is the change in position and not any other
serious problem.
It would be preferable for the child to stop eating at least 3 to
4 hours before the test.
Holter Monitor:
An electrocardiogram measures the heart’s electrical activity
of the child. However, it can only measure the activity during the
test, which only takes a few minutes. The problem in the rhythm of
the heart may occur at any time and may not appear during the test.
For that reason, a Holter monitor is used to measure the activity
over 24 hours. Patches attached to a tape recording the activity, is
placed on the chest of the child. During these 24 hours, the child
should behave normally and record all activities and symptoms if
any.
After 24 hours, the recorded EKG is checked by a doctor.
Oxygen Saturation:
In some children having symptoms like cyanosis, the amount of
oxygen in the blood can be low. An oxygen saturation test is used to
measure the blood’s oxygen level. This test is done by having a
sensor placed on the child’s finger. The machine gives then the
oxygen level and the pulse.
Anticoagulant monitoring:
Some children have an increased risk for blood clot formation.
These children usually have an artificial valve, a slow blood flow or
heart rhythm problems. They will need medicines to prevent the
formation of the blood clot. These medications will usually decrease
the viscosity of the blood making it less risky to form a blood clot.
The dose given should be monitored properly. If the dose is too
small, there is a risk for the child to form a blood clot but if the
dose is too high, there is a risk for the child to have an internal
bleeding.
The test done is called prothrombin test. It measures the time
needed for the blood to clot
When the child starts the medication, the prothrobin time should be
taken at least once a week until it stabilizes. Then once every two
weeks or even once every month is enough. According to the clotting
time, the dose may be increased or decreased.
Invasive:
Pacemaker placement:
Children and adults having some problems with the electrical
activity of the heart are advised to have a pacemaker placed.
The pacemaker is a battery connected to the heart with wires. The
heart takes the energy from this battery.
The problem with the pacemaker is that it can’t stay active for
a life time. It needs to be changed. It can last between 7 to 15
years.
The pacemaker can be placed in two different ways. The age of the
child can affect the method chosen. The child can either have the
pacemaker and the wires placed inside the chambers of the heart,
called transvenous, or can have the wires placed on the surface of
the heart called transthoracic.
The child has to stay for a few days in the hospital so that the
pacemaker and heart rhythm can be checked for proper function.
Heart catheterization:
The cardiac catheterization is used to open or close a blood
vessel like closure of an atrial septal defect. Interventional
cardiac catheterization can be done like balloon valvuloplasty and
angioplasty. Before deciding on a cardiac catheterization, the child
must have several tests done. These tests can include and EKG, chest
X-ray, stress test, and the most important one the echocardiogram.
During the catheterization, the child will be asleep. A catheter
will be used and will be placed into the heart. A contrast media
will be injected through the tube in the heart to take picture of
the heart. These pictures will help assess the need for the child of
an interventional catheterization. If a balloon is done, the child
may need to stay in the hospital for few days.
The cardiac catheterization is important because it can give us
information about the pressure of the blood inside the chambers and
blood vessels, as well as the oxygen saturation. In the presence of
a lesion or a hole, the oxygen-rich blood will mix with the
oxygen-poor blood.
The following are examples of heart catheterization:
1-Aortic Stenosis (AS)
2-Atrial Septal Defect (ASD)
3-Coarctation of the Aorta (COA)
4-Patent Ductus Arteriosis (PDA)
5-PDA Amplatz
6-Pulmonary Stenosis (PS)
7-Septostomy
Heart Surgery:
The heart surgery can be classified into two categories. The
open-heart and the closed-heart surgery. The closed – heart surgery
would include operations like banding and shunts. Open-hearts
surgeries would include all other interventions. The child has to stay
several days at the hospital and will be taken in charge by a team,
comprising a cardiology team and anesthesiology team.
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