The causes of tachycardia
Tachycardia or palpitations are the colloquial descriptions of the so-called tachycardia, a condition defined as a pulse rate of at least 100 beats per minute. Normally, the heart beats about 60 times per minute in adults; if it is greatly accelerated, a person affected perceives this as tachycardia, which can be accompanied by other symptoms. Actually, tachycardia is only a symptom and not an illness.
Under certain circumstances it can occur briefly in healthy people, as a concomitant of one of many other diseases, independently for a variety of reasons or sometimes even without any apparent reason. In some cases, tachycardia is not a cause for concern. In small children, for example, it is normal for them to have an elevated heart rate, which often exceeds 100 beats per minute.
Furthermore, the body wants the heart to beat faster in stressful situations. This means that more blood is distributed throughout the body and oxygen is brought to the tissues. Increased blood flow to the muscles makes sense during sports activities, which can lead to tachycardia.
Psychological stress also leads to an accelerated heartbeat, as the hormone adrenaline is released. This is supposed to put the body on the alert and make a fight or an escape possible. This requires increased heart work.
Many extreme psychological situations are accompanied by palpitations, including high psychological stress due to stress, nervousness, fear or even joyful excitement. Heart palpitations due to stress are not uncommon. Another cause can be a lack of fluid in the body (dehydration), which the heart wants to compensate for by increasing the beat frequency in order to keep the blood pressure stable.
Some causes of palpitations are in the heart itself. A distinction is made between ventricular tachycardia (the problem lies in the ventricle, which is the worse form as it is harder for the heart to compensate) and supraventricular tachycardia (the problem lies in the atria). For example, there may be additional conduction pathways or other disturbances in the heart’s complex excitation conduction system that lead to increased ventricular excitation.
Coronary heart disease, diseases of the heart muscle (cardiomyopathies) or of the heart valves can also cause a tachycardia. These various underlying conditions of the heart lead to a circulatory disorder of the heart muscle, which ultimately causes the symptoms and, more rarely, can also be caused by infections, inflammations or tumors of the heart. In addition, there are various diseases that originally affect a different part of the body, but secondarily affect the heart and lead to an accelerated pulse.
First and foremost, there are diseases of the thyroid gland, which lead to its over-functioning. These include, for example, the autoimmune disease Graves’ disease. Less frequent are: Mental illnesses such as anxiety disorders also cause the heart to go into a tachycardic state from time to time.
In addition, tachycardia can also be triggered by external factors. Above all, the excessive consumption of caffeine-containing drinks (especially coffee and cola) leads to a temporary tachycardia in many people. Other stimulants such as nicotine, alcohol and some drugs can also trigger tachycardia.
Certain drugs can also cause a tachycardia as a side effect. Poisoning, for example with some types of mushrooms, should also not be ruled out as a cause. In the context of sunstroke or heat stroke, most people also feel their heart racing.
The moreover one there is the heart racing as unspecific symptom as reaction to states of emergency of the body like: It can also occur that no reason at all can be recognized for a racing heart. In this case, one speaks of idiopathic tachycardia, but this is an exclusionary diagnosis. Another special case is congenital tachycardia.
This is caused by a defect in the excitation conduction in the heart and requires an operation by which it can be completely cured.
- Anaemia (low blood pressure)
- A lowered blood sugar level
- A high blood pressure (hypertension), which is usually the result of arteriosclerosis.
- Chronic lung diseases
- Disorders of the electrolyte balance of the body
- Hormone-producing tumors (the pheochromocytoma produces uncontrolled adrenaline, which makes the heart beat faster practically “for no reason”), which are associated with the same symptoms.
- Fever
- Inflammations (especially often it is observed for example in appendicitis)
- Allergy or
- The menopause.
We, as mammals, naturally have mechanisms in our bodies to protect ourselves from dangerous situations. When we find ourselves in situations that the body perceives as threatening and we get scared, our body activates an independently working nervous system, the sympathetic system, and sends signals to our adrenal medulla, in which messenger substances are produced that prepare the rest of our body to escape from the dangerous situation, in primeval times: by running away.
These messenger substances are called adrenaline and noadrenaline in our body. They dock to so-called G-coupled receptors on various organs and thus ensure that our blood pressure rises, our muscles are better supplied with blood, that the sugar reserves from the storage sites of our body are mobilized into the blood and, above all, that the heart rate is increased. Unfortunately, our body cannot distinguish whether we are in a physically dangerous situation or whether our fear is psychologically caused, i.e. it only prevails in our head and we are not faced with any tangible danger that we have to physically escape.
However, we now live in a time in which we often cannot escape dangerous situations by running away, but are even exposed to these situations every day, for example when we have a stressful workday or an unstressed work environment. Of course, there are many other factors that make us feel stress and which influence how much we let it affect us. Especially at night, when we try to find peace and quiet, our thoughts wander to the things that worry us and that we fear. Through the increased activation of the sympathetic system and the resulting increased release of adrenaline and noadrenaline, our heart rate increases and our heart beats faster. You can find more information on this topic here: Tachycardia due to stress
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