A condition where the number of heart contractions is measured from 90 and above beats per minute is called tachycardia. Heart palpitations as a result of fear, excitement or additional physical exertion is a normal physiological phenomenon. But there is still such a thing as pathological tachycardia. The reasons why this condition is considered harmful are as follows:
- the work of the heart becomes ineffective, as the blood supply to various organs and tissues of the body decreases due to lowering blood pressure due to incomplete filling of the ventricles with blood;
- due to the risk of developing a heart attack or coronary heart disease as a result of poor blood supply to the heart itself and a lack of oxygen while increasing the load on it.
This phenomenon is not considered a disease: it is known that with various diseases a symptom such as tachycardia manifests itself. The causes that are repeated more often are characterized by various forms of arrhythmia, disorders of the autonomous (otherwise, autonomic) nervous system, and hemodynamic disorders. They are explained by the structure and principle of the heart, which consists of four chambers: two upper chambers (atria) and two lower chambers (ventricles). The heart rhythm, as a rule, is controlled by the sinus node, which is located in the right atrium (more precisely, in its lateral wall), which is a natural pacemaker. The sinus node produces electrical impulses, usually starting with every heart beat. From the sinus node, electrical impulses pass through the atria, causing contractions of the muscles of the atria and the supply of blood to the ventricles. When electrical impulses reach the muscles of the ventricles, they are compressed, as a result of which the blood flows into the artery and flows to the lungs and other organs and tissues of the body.
The sinus node is excited with a frequency depending on the sympathetic (part of the autonomic nervous system, nerve nodes of which are located remotely from the innervated organs) and parasympathetic (part of the autonomic or autonomic nervous system, which works with the sympathetic nervous system) stimulation. In violation of the sympathetic or parasympathetic innervation, as well as in the pathology of the sinus node itself, sinus (or ventricular) tachycardia occurs . Its causes lie in the malfunction of the sinus node itself or in internal problems.
There are also external problems, for example, failures in the work of the autonomic nervous system. As a result of disorders in the sympathetic nervous system (increased stimulation), a rapid heartbeat appears , that is, tachycardia is observed. The reasons for the rapid heartbeat of healthy people are due to the use of caffeine. Disruptions in the endocrine system can be accompanied by an increase in adrenaline production and lead to tachycardia. External causes include the hemodynamic response when, with a decrease in blood pressure (due to loss of blood, a sharp change in body position or dehydration of the body), due to the feedback mechanism, the frequency of heart beats increases.
You can list the main causes of tachycardia.
- Damage to the heart muscle due to heart disease.
- Congenital anomalies of electrical impulses, as well as diseases and congenital anomalies of the heart itself.
- High pressure.
- Alcohol abuse, fever, smoking, drinking too many caffeinated drinks.
- A side effect of drugs.
- Abuse of recreational drugs such as cocaine.
- An imbalance of electrolytes, minerals necessary for conducting electrical impulses.
- Hyperthyroidism (hyperthyroidism). In some cases, the exact cause of tachycardia cannot be determined; it is called ideopathic.
How to cure tachycardia? The methods of treatment depend on the cause, age and health of the patient, as well as some other factors. The challenge is to slow the accelerated heartbeat, prevent subsequent episodes of tachycardia and reduce the risk of complications. Often it is enough to prescribe a treatment for hyperthyroidism. In other cases, when the cause is not found, the doctor will have to try other methods. To restore normal heart rate , antiarrhythmic injections (flecainide or propafenone) are administered. Exposure to the heart by electric shock (cardioversion in the heart affects electrical impulses and restores the normal rhythm) can be used in emergency care when other methods of treatment do not work. Implantation defibrillator - a cardioverter that controls the heartbeat and provides an electric current to restore the correct heart rate.