The heart has its own electrical system. Its function is to synchronize the muscle contraction in an effective way.










The electrical system is coordinated at the top of the heart, near the right atrium. 

The sinoatrial node, a cluster of cells, is the natural pacemaker of the heart. It initiates all the heartbeats and determines their pace and frequency.



The electrical signal generated in the sinoatrial node is transmitted to the atria and the ventricles, pacing through the "custom" node and then using a fast conduction network, the Purkinje network.







We often hear the word “arrhythmia” when talking about heart rhythm problems.


Two types of problems

A problem with the rhythm, or arrhythmia, is a problem with the electric system that makes the heart beat.

There are two main categories of problems: stimulation disorders and conduction disorders.


Stimulation disorders

Stimulation disorders are alterations in the synchronisation of the heart beats.

When the heart beats too fast, we call this “tachyarrhythmia” and “bradyarrhythmia” when it is too slow.

Certain stimulation disorders are present at birth.  They are qualified as congenital, not to be confused with hereditary diseases that are transmitted through the genes. Other problems arise from heart diseases such as heart attacks.

In general, stimulation disorders can begin at any stage of life and they manifest themselves in many different forms.

They can be without symptoms or cause palpitations, and they can be harmless or life threatening.



Conduction disorders

In this type of disorders, the electric current is not conducted adequately to the heart and therefore, does not make the heart function normally. In this category, we notice electric blockages of the heart.

These blockages are found in different places of our electric system; let it be the sinoatrial node, the atrioventricular node or the Purkinje network.

The main causes of the conduction disorders are the effects of certain medications or simply aging.

These problems can be asymptomatic (no symptoms).

It is also possible that the conduction malfunctions cause the heart to stop beating for a few seconds. These pauses may lead to weakness, dizziness or even loss of consciousness also known as “syncope.”



Recording of electrical disorders

Arrhythmia is visible on ECGs and on Holter monitors prescribed by doctors. The heart rate (slow, normal, fast), the extra beats (extrasystoles), abnormal beats, conduction disorders… all this information helps determine the exact location of the problem and what actions (medication or treatments) are necessary to solve the problem.


​Normal ECG






​ECG with stimulation disorder -Tachyarrhythmia: 160 beats per minute






​ECG with a blocage in the Prukinje network. Peaks are widened





To be continued

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The heart has its own electrical system. Its function is to synchronize the muscle contraction in an effective way.

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