Extrasystole is the most common heart rhythm disorder. This condition often occurs in absolutely healthy people and in some cases does not bring unpleasant sensations. But at the same time, extrasystolic arrhythmia can be a sign of diseases of the heart, spine, nervous system and other human organs. This type of arrhythmia is considered relatively harmless, and in certain cases is considered a variant of the norm. Nevertheless, there is a danger of passing into other, more dangerous forms of arrhythmia, which means that this condition can not be ignored. Let’s find out what are the causes of premature beats, its types, symptoms and possible consequences for the human body.
The work of the heart. Cardiac cycle
In order to understand how arrhythmias occur, it is necessary to recall the anatomy and physiology of the heart.
Our heart consists of four chambers – two atria and two ventricles. These chambers are a reservoir for blood. The main task of the heart is to constantly pump blood into the arteries. This happens due to rhythmic contractions. The cardiac cycle includes two phases-systole (contraction) and diastole (relaxation). On average, a cardiac cycle lasts 1 second, and normally 60-80 such cycles occur at rest.
Rhythmic contractions of the heart occur due to electrical impulses that occur in the heart itself. In the right atrium there is a group of special muscle cells that are able to generate an impulse. This structure is called the sinus node, or the pacemaker. pacemaker-sets the rhythm). Along the pathways, the pulse spreads to the atria, causing them to contract. Then it passes into the atrioventricular node, where it slows down for a fraction of a second. At this time, the ventricles of the heart are filled with blood. After that, the pulse propagates to another structure – the legs of the Gis beam, and then to the Purkinje fibers. This is accompanied by a contraction of the ventricles and the expulsion of blood from the heart into the blood vessels.
Ordered contractions of the heart are called automatism. This unique feature allows the heart to contract without external stimuli.
With the well-coordinated work of all the conducting structures of the heart, it works rhythmically and imperceptibly for us. In the event of a malfunction in this vital system, heart rhythm disturbances – arrhythmias-occur.
Causes of extrasystole
Extrasystolic arrhythmia – extraordinary contractions that are perceived by the patient as a sinking of the heart or its push, but may not be felt at all. This type of arrhythmia is also found in absolutely healthy people, usually against the background of stress and experiences. At the same time, the ECG can record up to 100 extraordinary contractions during the day.
Extraordinary contractions of the heart occur for two reasons:
- The presence of scars (after a heart attack or surgery) or ischemic areas of the heart. The electrical impulse, falling on these obstacles, returns back, causing an extraordinary contraction.
- Formation of an additional (ectopic) focus of pulse generation in the heart muscle. In this case, the heart contracts under the influence of natural impulses, and a secondary impulse will cause additional contractions.
The formation of an ectopic focus is the most common cause of extrasystolic arrhythmia. As a rule, this is the result of a lack of any resources, in which the normal work of the heart is not enough and the body is looking for additional options to stimulate its activity. Various provoking factors are possible:
- Stress, emotional experiences;
- Vegetative-vascular dystonia;
- Osteochondrosis of the cervical or thoracic spine;
- Problems with the thyroid and adrenal glands;
- Violation of water-salt metabolism – changes in the level of potassium, calcium, sodium and magnesium in the blood;
- Pregnancy or menopause;
- Violation of sleep and wakefulness, lack of proper rest;
- Heart diseases – heart failure, cardiosclerosis, ischemic disease, heart valve failure, endocarditis and myocarditis;
- Alcohol abuse and smoking;
- Increased body temperature in infectious diseases;
Symptoms of extrasystole
As we have already said, extrasystoles can occur unnoticed by a person. This type of arrhythmia is more difficult for people suffering from vegetative-vascular dystonia and having a labile nervous system. But patients with heart diseases, on the contrary, in some cases, tolerate extrasystoles easier.
Extrasystolic arrhythmias are characterized by the following symptoms:
- A feeling of fading or tremors in the heart, an uneven heartbeat
- Nervousness, anxiety, and irritation
- The feeling of lack of air, shortness of breath
- Dizziness, headache, weakness, sweating
- Pallor of the skin
Classification of extrasystoles
Extrasystoles are distinguished by:
– at the place of formation of the ectopic focus-ventricular, atrioventricular and atrial.
– by the number of ectopic foci – monotopic (1 focus) and polytopic (several foci)
– according to the frequency of extraordinary heart contractions – rare (up to 5 per minute), medium (6-15 per minute) and frequent (more than 15 per minute).
There are also paired extrasystoles – 2 in a row and group-several heart contractions following one after the other.
About 60% of extrasystolic arrhythmias are ventricular. In this form of arrhythmia, a secondary impulse occurs in the ventricular myocardium, which leads to their premature contraction.
In addition to the classic symptoms characteristic of arrhythmias, ventricular extrasystole can be manifested by pulsation of the cervical veins and a lack of pulse.
Ventricular arrhythmia in most cases is not a dangerous disease and has a favorable prognosis. But there is also a malignant course of ventricular arrhythmia, in which violations of the function of the heart are determined, threatening the health and even life of a person.
To simplify the diagnosis, ventricular extrasystoles are divided into classes:
Obviously, the higher the class of arrhythmia, the more dangerous it is and requires appropriate treatment.
Atrioventricular (supraventricular or atrioventricular) extrasystole is diagnosed less frequently than ventricular. Its cause is the appearance of pathological impulses in the border zone between the ventricles and atria or in the atrioventricular junction. In this case, there may be extraordinary contractions of the atria, or ventricles and atria at the same time. Atrioventricular extrasystole can disrupt the sequence of contractions of the ventricles and atria, and can keep it normal.
Atrial extrasystole can be manifested by extraordinary contractions of the atria, and sometimes the atria together with the ventricles. This form of arrhythmia is usually characterized by a prolonged diastolic pause, which is felt as a sinking heart.
Diagnosis of extrasystole
When making a diagnosis, it is important to determine the factors that led to extrasystole. To do this, the doctor conducts a survey and studies the history of concomitant diseases, if any. Then proceed to the diagnosis:
- Electrocardiogram (ECG) – records even those extraordinary contractions that are not felt by the patient. Extrasystole is manifested by an extraordinary (abnormal) QRS wave followed by a pause:
There are cases when extraordinary contractions of the heart occur only during physical exertion. In this case, the doctor can conduct a so – called stress test-ask the patient to work out on the simulator, and then study the work of the heart with the help of an ECG.
Unfortunately, an ECG is not always informative, since the moment of measuring the electrical impulses of the heart in the doctor’s office may not coincide with the appearance of additional contractions.
- Daily ECG monitoring (Holter monitoring) allows you to track the work of the heart for a long time and catch even rare single extrasystoles during the day. To do this, special sensors are connected to the patient, and the ECG measurement device itself can be synchronized with a computer. A special program will record and process the result.
- Electrophysiological examination of the heart (EFI) is an additional research method that allows you to record extraordinary contractions in the heart itself. To do this, a special catheter is inserted into the blood vessel of the inguinal region, arm or neck, which is promoted to the heart. This study is quite accurate, but brings the patient a certain discomfort.
The consequences of the arrhythmia
Frequent extrasystoles (more than 6 in 1 minute) lead to circulatory disorders. The fact is that with an extraordinary contraction, the heart expels a certain amount of blood. This means that during normal blood contraction, less blood will be released, and therefore the minute volume of blood will decrease. This can lead to the development of more dangerous forms of arrhythmia and complication of existing diseases of the heart and other organs. With malignant extrasystole, the anatomical structure of the heart is disturbed, and hemodynamics suffers. Extrasystole can transform into fibrillation, which is a life-threatening condition. The most dangerous outcome of an extrasystole is cardiac arrest.
Treatment of extrasystolic arrhythmia
First of all, they exclude the cause of extrasystole – they cancel provoking drugs, adjust the lifestyle, treat concomitant diseases. For single monomorphic extrasystoles, this may be sufficient. If the cause of the heart failure was stress and emotional stress, then sedatives may be prescribed.
In more serious cases, the doctor recommends beta blockers. They are also effective for high blood pressure and tachycardia.
Antiarrhythmic drugs are recommended for severe clinical signs, which are accompanied by obvious symptoms and are confirmed on an ECG. Some representatives of this group may, on the contrary, worsen the course of the disease. Therefore, the appointment of antiarrhythmic drugs requires a responsible approach.
At the first symptoms of arrhythmia, consult a doctor and take care of your heart!