Any disorder that causes the heart rhythm to be abnormal is known as cardiac arrhythmia. The beats are produced as a result of electrical impulses that allow the chambers of the heart – the atria and ventricles – to contract properly, synchronously and rhythmically. An average heart rate is between 60 and 100 beats per minute.
However, the heart rate alone is not enough to diagnose an arrhythmia. In fact, for example, 50 beats per minute can be considered normal for a trained athlete. “Apart from the heart rate, there has to be a clinical context that is not normal,” says the expert.
Arrhythmias are a widespread heart problem. It is estimated that only the most frequent type, atrial fibrillation, affects more than 4% of people over 40 years of age.
The causes of arrhythmias are very diverse. These are some of the factors that explain its appearance:
Many arrhythmias are linked to ageing. “With ageing, the system that creates the heart’s impulses also ages and disorders occur that make it beat more slowly,” explains Jiménez Candil. With age, the frequency of rapid arrhythmias also increases, in which the heart beats faster than normal.
Cardiovascular risk factors
Classic cardiovascular risk factors influence the appearance of arrhythmias. For example, hypertension, sleep apnea, obesity and diabetes are some of the diseases most closely linked to heart rhythm disturbances.
Structural diseases of the heart
Certain diseases that affect the heart’s structure, such as myocardial infarction or valvular heart disease, can lead to a heart malfunction since arrhythmias are generated in certain cases.
Some are born with a genetic predisposition to have arrhythmias and are people with familial heart disease.
no known cause
When the cause cannot be identified, they are idiopathic arrhythmias.
The clinical manifestations depend on the type of arrhythmia. They can vary, ranging from arrhythmias without symptoms to others that cause important repercussions. The main symptoms are:
Under normal conditions, the heartbeat is not perceived. The perception that the heart beats is known as palpitations; palpitations do not always indicate a pathological situation or mean that there is tachycardia.
Some affected people may experience dizziness and even syncope. The relatively sudden loss of consciousness is known as syncope and is characterised by spontaneous recovery in a short period. Some syncopes may be due to slow arrhythmias ( bradycardias ) and others to fast arrhythmias or tachycardias.
- Fatigue or tiredness
Intolerance to exertion, tiredness, fatigue, choking sensation when walking, and chest pain is other possible manifestations of some arrhythmias.
- Sudden death
Sudden death is a cardiac arrest that occurs unexpectedly and suddenly. It is primarily triggered by cardiac arrhythmia, mainly ventricular fibrillation, but also ventricular tachycardia and, less commonly, bradycardia.
Among the measures that can be adopted to prevent the formation of arrhythmias, the following stand out:
- Reduce the consumption of sugars and fats to reduce hypercholesterolemia and diabetes.
- Play sports regularly.
- No smoking.
- Avoid alcohol.
- Control and reduce stress levels.
We can find the following types of arrhythmias:
- sinus bradycardia
This is a situation where the heartbeat originates and transmits normally, but the heart rate is slower than normal.
Sinus bradycardia can occur in different situations: it can be completely normal and physiological, as is the case with athletes; it may be due to certain medications; to the involvement of the sinus node itself and can be found in the context of an involvement known as bradycardia/tachycardia syndrome in which patients alternate episodes of significant bradycardia with gusts of tachycardia episodes (usually atrial fibrillation).
Isolated sinus bradycardia is usually a physiologic condition and does not require treatment. , Drugs can also cause it, and the possibility of withdrawing them must be assessed. If it is severe and symptomatic, the treatment is the implantation of a pacemaker.
- atrial fibrillation
It is the most common cardiac arrhythmia. It is generated because the atria are activated and contract in a disorganised, irregular and inefficient way, which causes the ventricle to beat irregularly.
It can be paroxysmal (occurs in short episodes lasting less than a week and usually comes and goes on its own), persistent (when episodes last more than a week and often do not go away without treatment), or permanent (occurs constantly).
There are several therapeutic options for patients who present with repeated AF crises.
- Drugs: Various antiarrhythmic drugs may be helpful. It should be noted, however, that no drug is effective in all patients and that they may have serious side effects or contraindications that limit their use.
- Radiofrequency ablation of the AV node and implantation of a pacemaker: This alternative consists of causing a heart block with radiofrequency and subsequently implanting a pacemaker. With this technique, the AF is not eliminated, but the patient stops noticing the vibrations, and their symptoms improve.
Direct radiofrequency ablation of AF: In some highly selected patients with specific types of AF, it may be considered to perform an ablation directed at the points where the AF begins, which could be curative.