Electrocardiogram (ECG or EKG)

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  5. Electrocardiogram (ECG or EKG)

The heart has its own electrical system. Its role is to synchronize the work of the cardiac chambers (atria and ventricles) in an effective way.

A recording of the cardiac electricity

The electrocardiogram is the recording of the electricity generated by your heart.

The electricity of the heart can be recorded by the installation of small electrical sensors on the skin.

An ECG (or EKG) is specific to each person. It is like a fingerprint.

An easy test, done basically without preparation

It is an easy, painless test, not requiring any preparation.

Usually, it does not require an appointment.

And what can we see?

The ECG provides information on the heart rate, the beat regularity and the presence of anomalies in the cardiac muscle.

Of short duration

An ECG records the cardiac electrical cycle, beat by beat over a period of about 10 seconds.

Regularity and heart rate

Each “peak” on the ECG corresponds to a contraction of your heart. We can then see the “tempo” which is usually quite regular.

Apart from the tempo, we can also appreciate the speed of the heart (the heart rate).


“Bumps” and “spikes”

The bumps and spikes seen on an ECG recording represent the electricity going through the various parts of the heart.


The first “bump” represents the passage of the electrical wave through the atria.


The “spike” represents the passage of cardiac electricity in the “highway” of the Purkinge network in the ventricles.

The “customs officer”

The portion including the first bump and the spike is the time it takes to go from the atria through the electrical “customs officer”.

The “reset” of the ventricles

Finally, the last bump represents the electrical “reset” of the ventricles. After this period, they will be ready for another electrical passage.

Any obstacle leaves a mark

Any obstacle to the passage of electricity will cause modifications on the recording.

The absence of the atrial bump, the widening of the “spike” or the prolongation of the time required to go through the “customs officer” indicate rhythm disturbances or conduction disorders.

Anomalies in the cardiac muscle like a heart attack, a thickening of the heart muscle or a dilatation of the heart cavities will also cause specific electrical anomalies.