The different types of arrhythmias
BRADYCARDIA
The frequency of heartbeats is usually between 60 and 100 beats per minute.
When the heart beats slower, below 60 beats per minute, the heart rate is in bradycardia.
Bradycardia can be physiological, especially in athletes, or iatrogenic when taking various medications including certain beta-blockers.
It can be asymptomatic, so regular medical monitoring is advised.
In the presence of symptoms, patients may experience dizziness, fainting, fatigue, shortness of breath...
What causes bradycardia?
It is an anomaly of the electrical circuit in the heart, which can be found at different levels, such as the sinus node or the atrioventricular node at the junction between the atria and the ventricles.
TACHYCARDIA
When the heart rate exceeds 100 beats per minute, the patient experiences tachycardia.
This acceleration of the heart rate can be physiological (during exertion), in response to an inflammatory, infectious, or metabolic condition such as hyperthyroidism, or pathological, related to an abnormality in the heart's electrical circuit.
Tachycardias originating from an abnormality in the electrical circuit can lead to the following arrhythmias:
1- Inappropriate Sinus Tachycardia: inappropriate acceleration of the heart rate at the sinus node.
2- Supraventricular Tachycardias: such as Bouveret's disease (intra-nodal re-entry) or tachycardias with an accessory pathway (Wolff-Parkinson-White).
3- Atrial Fibrillation: the most common arrhythmia worldwide, which begins in the left atrium and causes an irregular heart rate.
4- Common Flutter : a fast electrical circuit present in the right atrium.
5- Atrial Tachycardia: a fast electrical focus that can be located in the right or left atrium.
Ventricular tachycardias can originate from the right or left ventricle. They can be indicative of a structural abnormality of the heart muscle such as a history of myocardial infarction.
Wolff-Parkinson-White Syndrome:
Wolff-Parkinson-White syndrome is related to the presence of a Kent bundle: it is an accessory pathway associated with the presence of an additional muscular bundle. This additional bundle may cause palpitations.
The diagnosis of an accessory pathway is made on an electrocardiogram. This should be evaluated with potential planning for an endocavitary electrophysiological exploration performed by a electrophysiologist to assess its dangerousness.
Bouveret's disease:
Bouveret's disease or supraventricular tachycardia is a heart rhythm disorder characterized by an accelerated heart rate in the upper region of the ventricle. This can be increased during palpitation episodes, reaching over 180 beats per minute. Symptoms may include palpitations, discomfort, shortness of breath, nausea, loss of consciousness, and a feeling of impending death.
This condition is prevalent at any age.
The diagnosis can be made on an electrocardiogram performed during a palpitation episode and will be confirmed during a therapeutic endocavitary exploration.
Curative treatment is performed during endocavitary electrophysiological exploration with ablation of the arrhythmogenic substrate.
Atrial Fibrillation:
Atrial fibrillation or atrial fibrillation (AF) is the most common arrhythmia in the world. One in four people will be affected by this arrhythmia during their lifetime, starting at the age of 40. It is particularly prevalent from the age of 65 onwards and more common in men. Risk factors such as high blood pressure, diabetes, sleep apnea syndrome, etc., can increase the prevalence of this arrhythmia.
AF is a heart rhythm disorder in which the atria contract chaotically and irregularly, followed by a potentially rapid contraction of the ventricles. This reduces the efficiency and performance of the heart pump and increases the risk of stroke.
