What examinations are required?
To find out whether a chest pain is due to coronary artery disease, your doctor
may perform additional examinations.
The simplest examinations will check whether the ischaemia is apparent when
your heart has to cope with exertion.
An electrocardiogram (ECG)
If there has been no previous myocardial infarction, the ECG recorded outside
an angina episode is very often normal. It is only during the episode that
the cardiologist will note abnormalities indicating the presence of the ischaemia
and its location.
The ECG may show the scar of a previous infarction.
An exercise test
This consists in recording the ECG during exertion. It is performed on a so-called “ergometric” bicycle
(similar to an exercise bike) or on a treadmill whose speed and slope can be
adjusted.
The intensity of the exertion is increased progressively until your heart reaches
the maximum cardiac frequency (a theoretical value = 220 – age) or until
pain occurs or abnormalities appear on the ECG.
The exercise tolerance test is not always possible for very old people, or those
who have a motor handicap, or for certain patients for whom it is contraindicated.
An exercise test combined with a scintigraphy of the myocardium
To confirm the diagnosis, radioactive tracers that attach themselves to the healthy
cardiac muscle can be used in addition. In practice, an IV injection of the tracer
is performed at the end of the exercise test. You are then placed under a camera
which measures the radioactivity and produces an image of the myocardium, the
scintigraphy. A second image is taken a few hours later, at rest.
The areas that are poorly oxygenated as a result of stenosis or the constriction
of coronary arteries do not fix the tracer and appear as “holes” in
the image taken just after the exertion; in the image taken at rest, these holes
are visible if there has been an infarction, otherwise they disappear.
An echocardiography or stress echocardiography
An echocardiography is a method of ultrasound imaging. It shows the cavities
and walls of the heart and valves and their functioning during the cardiac cycle.
The scars of an infarction, i.e. areas which have lost their power of contraction,
can thus be seen.
However it does not show the coronary arteries directly.
The stress echocardiography consists in analysing the behaviour of the left ventricle
when the cardiac work is increased.
To do so, a drug is injected which accelerates the heartbeat. If the coronary
arteries are normal, the contraction of the ventricle becomes more vigorous and
uniform. If an artery is constricted, the corresponding area does not contract
normally. The “viability” of these areas, i.e. the possibility of
normal function being resumed, can also be identified by taking certain drugs.
A coronary angiography
A coronary angiography can confirm the coronary artery disease and determine its extent
and seriousness. It can also help select the most appropriate treatment for your
lesions: either by dilatation (coronary angioplasty) or an operation (bypass).
 Principles
To be able to see the arteries, the blood has to be made opaque to X-rays by
injecting a radio contrast medium. A film is then made showing the network of
arteries through which the “opacified” bloo
d flows. The stenoses
formed by the atheroma deposits are thus perfectly visible.
The disease is particularly serious when it affects several coronary arteries
and the stenoses are close to their starting-point.
Most often a ventriculography is practiced, which is an image of the inside of
the heart to assess the quality of its contraction.
Before the examination
Except in the case of an emergency (acute coronary syndrome), you will be hospitalised
for 24 to 48 hours. Sometimes, you will be able to leave the same evening.
You must not have had anything to eat or drink beforehand, indicate all the medicines
you are taking and whether you have already had a problem with X-rays (“allergy
to iodine”). A blood test will be made to check the functioning of your
kidneys. The nurse will also generally give you a drug for anxiety. The doctor
will explain how the examination is to be performed, its aim and risks, and will
have you sign an “informed consent” form (the patient consents after
being given clear and appropriate information by his doctor).
The examination room
The examination room can be quite overwhelming because of the equipment (X-ray
unit, monitoring…). The doctor is assisted by a nurse who supervises the
equipment and often by an X-ray operator who checks the quality of the images.
The examination itself
The nurse inserts a drip to be able to make injections if necessary and then
settles you on a narrow mobile table.
The cardiologist administers a local anaesthetic at the puncture site of the
artery (a simple pinprick), the application of an anaesthetising cream to the
side of the groin is also possible.
During the examination the X-ray unit will be moved around you since the arteries
are all around the heart and move with every contraction.
In the same way as for a normal X-ray, you will not be put to sleep and you will
sometimes be asked to hold your breath for few seconds. You will then be able
to see your coronary arteries on the screens and ask for explanations as the
examination proceeds. The examination can last from 20 minutes to over an hour
and is not painful. However, you should point out to the doctor any abnormal
sensation (pain...).
Technique
Preparation: The femoral artery is generally the injection point, located at
the side of the groin, where very thin tubes known as probes or catheters are
inserted. They are used to reach the coronary arteries located at the base of
the heart.
Coronary angiography: the probes are then linked up to a syringe used to inject
the radio contrast medium quickly. Generally several injections are made to be
able
to see all the branches of the coronary arteries. With each injection, you will
feel a painless hot flush lasting for 1 or 2 minutes.
 A ventriculography requires the injection of more radio contrast medium into
the left ventricle, which provokes a sensation of heat throughout the body lasting
a few seconds.
At the end of the examination, the probe is removed and the artery is compressed
for about fifteen minutes. If the puncture site is located in the groin, you
will remain lying down for a few hours, flat on your back, to allow the artery
to heal and avoid bleeding.
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