Arrhythmias
Epidemiology
We distinguish :
- Familial forms: rare with, for the most frequent, a prevalence of 1/2500-5000 births
- Acquired forms, which are very common, in particular atrial fibrillation which affects 1.5-2% of the population and more than 12% of those over 80 years old.
Number of deaths
First cause of sudden death, especially before the age of 35
An important cause of decompensation of heart disease, that is to say heart failure which is one of the leading causes of death in Europe.
Average age
Overall, women are affected as much as men even if, for certain arrhythmias, there may be a gender effect.
Distribution man / woman
We distinguish :
- Familial forms: rare with, for the most frequent, a prevalence of 1/2500-5000 births
- Acquired forms, which are very common, in particular atrial fibrillation which affects 1.5-2% of the population and more than 12% of those over 80 years old.
Symptoms / Severity
Most often, arrhythmias are responsible for a feeling of abnormal heartbeat, palpitation, irregular heartbeat, “missing.” But they can be asymptomatic, diagnosed during a recording of the electrocardiogram or after a syncope, an attack of heart failure, or sometimes, on the occasion of a sudden death.
Extrasystoles, premature beats felt like a miss, which can be auricular or ventricular, are most often benign and fairly commonplace; but they can be the harbingers of a more serious arrhythmia, this is one of the circumstances that lead to investigating the risk of arrhythmia occurring.
Causes / Risk factors
The main risk factor for arrhythmias is the presence of heart disease, cardiopathy, linked for example to myocardial infarction, valvulopathy or the impact of arterial hypertension. In this case there is a modification of the heart muscle, the myocardium, with in particular the appearance of fibrosis (replacement of the muscle by an inert supporting tissue) which alters the electrical activity of the heart and promotes the onset of a rhythm disorder .
Other causes of arrhythmia are genetic abnormalities. This ranges from rare mutations affecting a gene, as in the case of familial long QT syndrome, to frequent mutations, called polymorphisms, certain combinations of which create a favorable ground for the occurrence of an arrhythmia, as we speak today. polygenic risk factor.
Evolution / Consequences
Arrhythmias can progress to a paroxysmal mode with acute episodes, or, as is the case for atrial fibrillation, to a persistent then permanent form.
In addition to acute complications related to paroxysmal episodes, sudden death syncope, the repetition of episodes of arrhythmias or their persistence leads to a less efficient functioning of the heart pump with a risk of developing heart failure.
A major complication of the most frequent arrhythmia, atrial fibrillation, is arterial embolic accident, particularly cerebral stroke.
How is it treated?
Three main types of treatment:
- Drugs: Antiarrhythmic drugs that target the proteins responsible for the electrical activity of the heart. Beta blockers, which inhibit the effects of adrenaline on the heart, are today the first treatment for arrhythmias.
- Ablation of the arrhythmogenic zone using probes introduced inside the heart by venous or arterial route under local anesthesia
- Implantation of a defibrillator pacemaker to prevent sudden death
Is there any research on this pathology?
This is one of the most active fields of cardiovascular research, from the molecular bases of cardiac excitability and arrhythmias, in particular the identification of genes, to the development of new probes for the ablation of imaging of arrhythmogenic areas.
It is also one of the most active sectors of telemedicine.
ICAN's response
The IHU ICAN teams are major players in this field
- They are international leaders in the field of research on atrial fibrillation, they coordinate a vast European network in this field. Their work has also contributed to a better understanding of the cellular and molecular bases of cardiac excitability.
- They have contributed to a better understanding of familial forms of arrhythmias, in particular to the description of arrhythmogenic dysplasia, to the discovery of new genes (long QT, dysplasia, Brugada).
- The cardiology institute is one of the first centers in France, the first in Paris, for the management of these arrhythmias and a reference center for family forms.
