The supply of oxygen to all tissues and organs occurs thanks to the heart, which creates pressure and pumps blood. In this case, the heart muscle should contract about 55 to 80 times in 60 seconds. The whole body depends on the rhythm of the heartbeat.

If the intervals between contractions are equal, then the cells regularly and continuously receive the required amount of oxygen and all processes in the body remain normal, but due to the slightest disruption in the work of the cardiovascular system, tissue hypoxia occurs, which turns into more problematic pathologies. Very often, a heart block becomes the cause of a lack of oxygen in the brain and other organs.

How does pathology appear and what is it?

The origin of the impulse occurs due to the sinus node, which sets the rhythm. The impulse moves to the atria and, as a result of their contractions, is transmitted to the bundles and nodes of the system. After that, the wave moves along the smallest channels of the body and Purkinje fibers.

Interruption of this process leads to a delay in the impulse in certain areas and leads to various diseases. Blockages are called pathologies that relate to heart rhythm disturbances - to arrhythmias.

Sometimes, myocardial conduction is completely isolated by the blockade. And also blockades can be combined with different types of arrhythmias or be combined with other blockades. Most often, blockages develop in older people, less at a young age.

The main danger of a blockade is a delay in myocardial contractions, which can vary from a tenth of a second to a whole minute or more. Subsequently, the person may have oxygen starvation, fainting and clinical death.

Heart block symptoms and treatment - it all depends on the individual organism. The deterioration of the condition will also depend on the cause of the blockade and the place of appearance in the conducting system. Pulse blocking can occur both in the atrium and in one of the ventricles.

Types of blockades

An important indicator in the diagnosis and treatment of the disease is the severity of the violation of the passage of excitability. For this factor, pathology is divided into the following types:

• blockade of 1 degree - poor passage, but an excitation pulse is carried out;
• blockade of the 2nd degree - the complete cessation of the passage of the impulse to the ventricles, which is very dangerous and often leads to death.

Pathology is distinguished by the place of education:

• sinotrial block - affects the sinus node;
• atrial block - impaired impulse in the atrium;
• interatrial - interruption of the impulse on the way to the left atrium from the sinoatrial node;
• transverse or atrioventricular - a violation during the transition of the impulse to the ventricles from the atrium;
• intraventricular - blockade of the lower part of the left or right leg of His.

In turn, intraventricular pathology is divided into the following types:

• interventricular - the pathways of the ventricular septum are affected;
• right ventricular block - interruption of the impulse in the anterior or posterior branch of the left leg of His;
• left ventricular block - interruption of the impulse anywhere in the left leg of His;
• left ventricular block.

Types of pathology by time of appearance:

• transitional;
• continuous;
• progressive;
• intermittent.

Factors in the appearance of blockades

A partial blockage can occur in a healthy person without causing any harm. For example, small heart anomalies can lead to the appearance of a partial blockade of the right branch of the His, which does not develop further and does not change its position.

Blockade of the first degree can appear in young people due to intense sports activities or strenuous physical work. In some cases, heart block may be congenital.

Such a pathology appears in violation of intrauterine development. In this case, a defect of the heart valve and other disorders of the cardiovascular system are observed, which are found in a child immediately after his birth.

Causes of blockades

There are a number of main causes of pathology:

• autoimmune disease;
• thyrotoxicosis;
• diphtheria;
• myocarditis;
• vasculitis;
• acquired heart disease;
• tumor or metastasis of the myocardium;
• myxedema;
• sarcoidosis;
• amyloidosis;
• heart attack;
• fibrosis;
• hypertension;
• violation of metabolic processes;

And there is also the likelihood of blockages from taking glycosides, antiarrhythmic drugs, beta-blockers. Pathology can appear after surgery, as well as complicate various types of operations. Myocardial conduction is impaired from drug use and alcohol overdose.

Symptoms of the manifestation of pathology

In most cases, mild degrees of the disease do not cause any discomfort in a person.

Partial blockages are only detected with a cardiogram, routine health check-up or routine check-up.

However, incomplete heart block presents a risk of possible complications. Sinoauricular blockade, when the impulse stops or slows down, the patient feels pain in the chest area, suffers from shortness of breath, weakness, decreased performance and dizziness.

And in such cases, when the impulse often slows down, stops, with a complete blockage of the heart, the person has a feeling of cardiac arrest, frequent dizziness, accompanied by tinnitus and passing into a fainting spell.

Pronounced symptoms appear with a complete blockade of the heart of the AV node. Such blockages are manifested by arrhythmia and bradycardia, and can also show signs of an underlying heart disease.

There are cases when, when a person feels normal, he suddenly has arrhythmia. If the deterioration in the body lasts a long time, then the person adapts and feels good.

The patient may have seizures against the background of blockades. They are distinguished by the level of the patient's condition:

• mild form - a person does not lose consciousness, but suffers from dizziness, feels tinnitus, limbs go numb;
• moderate severity - the patient may lose consciousness, while there are no seizures, urination does not occur;
• severe form - a mild and medium form of an attack is combined. Without action, it can be fatal.

Such seizures often occur in people with atrioventricular block. The attack can be repeated, and the frequency of repetitions and the gap between them depends on the organism.

Indicators of serious conduction disturbances

When the heartbeat slows down to 50 beats per minute, the person complains of dizziness. And there are also other symptoms of blockages:

• the person gets tired quickly;
• physical activity is felt in a greater equivalent;
• unpleasant sensation in the chest area;
• playing sports brings pain in the chest;
• pain in a calm state;
• short-term cardiac arrest;
• darkening in the eyes;
• sudden weakness and dizziness;
• nausea;
• feeling of noise and ringing in the ears;
• headache, mostly in the occiput.

If a child is born with a pulse of less than 80 beats per minute, then he is given a cardiogram. The pulse rate in children should be higher than that of adults. In this case, the complete blockade is confirmed or refuted. This pathology is sometimes found in utero.

With atrioventricular block, the child is pale, with a slow heartbeat and is lagging behind in development. And also may refuse to feed. Subsequently, insufficient blood circulation in the baby often faints, convulsions and seizures. With a prolonged attack, breath holding and cardiac arrest are possible. Congenital blockage can be the cause of the death of a child in the early stages of life.

Blockade diagnostics

When symptoms of the disease appear, the doctor can learn about violations when decoding analyzes and examining a patient. By listening to the work of the heart, the doctor can determine irregularities in the heartbeat, as well as heart failure characteristic of some. Most often, the disease is diagnosed by means of electrocardiograms, thanks to which it is possible to accurately determine the type of disease.

To determine the blockade, a one-time electrocardiogram is not enough, the procedure may be ineffective. To obtain more accurate results, it is recommended to conduct a Holter examination.

Such a procedure is performed within 24 hours, and the result of the procedure is information about transient blockages, heart rhythm problems. In patients, heart block is often checked on an ECG with stress, which allows you to establish the level of permissible physical activity and the class of heart failure. Other methods of examination are also used to detect the causes of pathology:

• holter monitoring;
• radiography of the lungs;
• coronary angiography;

Various laboratory tests and other studies may be required to obtain accurate information.

Treatment with medication

With the help of medications, heart block can be treated and the heart rhythm restored. In this case, an effect on the pathology itself occurs. With a partial block, most often the patient only needs observation and a healthy regimen.

If the pathology began as a result of an overdose or prolonged use of drugs, they must be canceled immediately. Sometimes, for myocardium caused by an autoimmune disease, antibiotics, NSAIDs, glucocorticosteroids and statins may be required.

Drug therapy includes taking such drugs:

• beta blockers - Betalok;
• beta adrenostimulants - Isoprenaline or Orciprenaline;
• diuretic - Furosemide;
• vasodilator - Amlodipine;
• antiarrhythmic drugs - Quinidine;
• calcium channel blocker - Corinfar and Nifedipine;
• antihypertensive substance - Perindopril and Enalapril.

Surgical intervention for blockages

Unfortunately, in contrast to partial blockages, some types of blockages cannot be cured with medication. In such cases, the only way out with positive results is surgery.

When a patient has heart attacks, pacemakers are most often installed. There are also some factors that require continuous use of a pacemaker:

• a big difference in the decrease in heart rate;
• a combination of a complete blockade with ectopic arrhythmia, heart failure and other heart diseases;
• impaired conductivity and hemodynamics at the same time;
• asystole that lasts up to 2 seconds.

For heart attack or other serious complications, a temporary pacemaker may be inserted.

Power mode during blockages

The diet and products consumed by the patient are of great importance for any type of blockade related to the passage of the impulse. It is recommended to eat foods that contain potassium, calcium, magnesium and other minerals that nourish the myocardium. The patient's condition is positively influenced by the use of products with useful minerals:

• baked potato;
• sunflower seeds;
• banana;
• dried apricots;
• black currant;
• dried fruits;
• spinach;
• beans;
• cucumbers;
• avocado;
• seafood;
• pumpkin seeds.

In the patient's diet, it is necessary to include more plant products in which there are more vitamins, as well as limit the consumption of salty, fatty and sweet foods.

Prevention of pathology

Most often, first-degree heart block becomes a complication of the underlying heart disease. Therefore, preventive measures are to treat heart failure immediately after the detection of symptoms of pathology. In this case, it is necessary to monitor the dosage of the medication taken to prevent overdose, as well as to stop using harmful substances.

Assisting with the blockade

Blockages can develop and proceed with complications. At the same time, the occurrence of seizures predisposes to knowledge of first aid and further actions. The patient should be placed on a flat surface with a small pillow under his head. An Isadrin tablet is placed under the patient's tongue, and in case of loss of consciousness, take action and bring the patient to life.

In the absence of pulse and respiratory arrest, perform indirect myocardial massage and artificial respiration. Providing such assistance before an ambulance arrives can save a person's life.

With an elevated cholesterol level and a tendency to be overweight, it is necessary to take measures to lose weight, since the load on the heart also depends on the weight of the human body.

With blockages of any type, smoking and alcohol abuse are prohibited. You need to lead a healthy lifestyle. Your life schedule needs to be replenished with moderate exercise. Children with congenital or acquired complete blockages cannot live like their peers.

They cannot serve in the army and perform heavy physical activity, attend sports sections and clubs. Pregnancy with blockages needs to be planned, while doctors will decide on an individual basis whether carrying is possible.

In some cases, AV block is not accompanied by any symptoms or impairment of the general condition.

Types of atrioventricular block:

Features of 1-degree transient AV block

A transient, or acute, atrioventricular block can last only a few seconds. During this time, a sharp drop in pressure leads to a stop in the conduction of an electrical impulse caused by a malfunction of the ANS (autonomic nervous system).

Transient AV block can lead to tachycardia, ventricular ectopia, or fibrillation. It is possible to prevent complete transient blockade by prescribing atropine.

In the absence of damage and changes in the AV node, transistor blockade has a vagal character, which occurs when the pressure drops sharply during stress, blood transfusion or severe vomiting. It can also disturb with a sharp transition from a prone position to a sitting position.

In older people with an increased tone of the vagal nerve, there is a strong slowdown in sinus rhythm and the manifestation of blockade in stage 1, which is eliminated by atropine.

Etiology of impulse conduction disorders

• Increased tone of the vagus (vagus nerve).
• Electrolytic disturbances with violent vomiting.
• Drug overdose.
• Stress and overwork.

Treatment

Stage 1 transistor atrioventricular block is considered the norm for young active people and does not require treatment.

Therapeutic measures are carried out upon detection of concomitant problems in the work of the heart muscle and heart as a whole, they are aimed at eliminating the cause of conduction disturbances in the AV node.

If a blockade is suspected, the patient is referred for diagnostic measures:

Stage 1 blockade can be caused by taking medications:

• cardiac glycosides;
• antiarrhythmic drugs;
• beta-blockers.

In such cases, these drugs are canceled, if it is impossible to cancel, the dose is adjusted.

Violation of conduction in the AV node in children

Transistor AV block of 1 degree in childhood is a common occurrence. It can be caused by a pathological pregnancy of the mother, a negative environment, and unbearable physical activity.

In newborns, the heart rate ranges from 140 beats to 170, a decrease in the rate to 100 is considered bradycardia and requires additional diagnostics to identify the problem.

If the first degree is violated, the clinical manifestations may not bother the child, but parents need to pay attention to the appearance of such signs:

• Bluish or very pale skin.
• Highlighted nasolabial triangle.
• The baby does not breastfeed or suckles very weakly.
• The baby sweats profusely.

If the violation is of a functional nature, then the prognosis is usually favorable, in the future the problem is not aggravated, and relapses are not observed.

To prevent blockade of the first degree, cardiologists prescribe regular monitoring of the condition of children, at least twice a year.

First aid for an attack

The blockade attack requires immediate action. It is necessary to call an ambulance team, but even before the arrival of doctors, the patient is given first aid.

The person is laid on his back, a pillow is placed under his head. To relieve the condition, you can give izadrin, one tablet under the tongue. If the patient has lost consciousness, artificial respiration and chest compressions will help bring him back to his senses.

The ambulance team will take the following measures:

• Intravenous administration of epinephrine and norepinephrine.
• Atropine is injected subcutaneously.
• A blockade of the cardio-aortic plexus with novocaine is performed.
• Defibrillator in use.

The patient is urgently hospitalized in the intensive care unit.

Diet food

After diagnosing a patient with a transient blockade of 1 degree, cardiologists recommend changing the diet.

To improve the conductivity in the AV node, it is necessary that the foods consumed have enough potassium, magnesium and calcium.

Products that improve the conductivity of the AV node:

Salty and smoked products, confectionery sweets, artificial fats are excluded from the diet. With obesity, you need to lose those extra pounds that put stress on the heart.

Transient AV block: what you can't eat:

• lard, meat with fat;
• animal fats, butter;
• strong broths;
• canned food and marinades;
• sour cabbage;
• seasonings and sauces with hot peppers;
• chocolate;
• coffee;
• cocoa;
• black tea;
• alcoholic drinks;
• carbonated water.

On the table of a patient with cardiological disease should be vegetables, preferably fresh or stewed in olive oil, cereals, boiled, lean meat, dairy products.

With high cholesterol, the number of eggs is limited, it is advisable not to serve them as a whole, but to add them to dishes according to the recipe. Fresh bread made from white flour is being replaced by bread made from wholemeal flour, yesterday's baked goods.

Transient heart block. Lifestyle

In addition to a diet aimed at strengthening the body and restoring conduction, patients should give up bad habits, alcohol, cigarettes, and drugs.

Correctly organized daily routine, physical activity contribute to the rapid restoration of a healthy state.

Patients with impaired transient conduction are prohibited from physical overload, work associated with stress.

With an increase in health problems, cardiologists recommend that people who have undergone a transient blockade undergo a full examination, since the blockade, which has grown into a severe degree, can be fatal.

Transient AV block. Treatment with folk remedies

Traditional medicine recommends rose hips to recover from seizures. Five tablespoons of rose hips are boiled in water (500 ml), the boiled fruits are ground with honey. The broth is drunk before eating, half a glass.

To restore the passage of an electrical impulse in the AV block, valerian root is used. A decoction of the root soothes, restores the work of the heart muscles and the AV block.

Horsetail preparations restores the work of blood vessels and the heart as a whole. To prepare the product, two teaspoons of raw materials are poured with a glass of boiling water, after which they insist for fifteen minutes. Horsetail is taken every two hours, two teaspoons.

Hawthorn helps to normalize blood circulation, pressure and relieve the excitability of the central nervous system. To prepare the product, ten grams of dry raw materials and 100 ml of vodka are used.

The drug is infused for ten days. The finished, strained drug is taken three times a day, ten drops per water, before meals.

Lemon balm infusion has a sedative effect and restores the nervous system. To prepare the infusion, you need to take one tablespoon of dry herb and pour a glass of water. The drug is taken four times a day for a quarter of a glass.

Taking folk remedies, it must be remembered that no decoction can replace the consultation of a cardiologist, therefore, regular examinations for people with cardiac problems are a necessity to help prolong life, and often save it.

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AV block

Depending on the severity of the AV block (atrioventricular block), it can be grade 1, 2, and 3 (complete).

1st degree AV block is an extension of the PQ interval of more than 0.20 s. It is found in 0.5% of young people without signs of heart disease. In the elderly, 1st degree AV block is most often the result of an isolated disease of the conducting system (Lenegra's disease).

With 2nd degree AV block, some of the atrial impulses do not reach the ventricles. The blockade can develop at the level of the AV node and the Hisa-Purkinje system.

2nd degree AV block with 3: 1 conduction.

• If during AV block (for example, with conduction 4: 3 or 3: 2) the PQ intervals are not the same and the Wenckebach period is observed, they talk about AV block of the 2nd degree of the Mobitz I type.

• In Mobitz I type 2 AV block, QRS complexes are usually narrow because the block occurs above the bundle of His at the level of the AV node.

• Even if a bundle-branch block is observed with Mobitz I AV block, the level of AV block is most likely at the level of the AV node. Nevertheless, in this case, an electrogram of the His bundle is required to confirm the level of blockade.

Advanced AV block (3: 1, 4: 1 and higher) refers to the 2nd degree AV block of the Mobitz II type. In this case, QRS complexes are usually wide (a blockade of the right or left bundle branch is characteristic), and the level of blockade is below the AV node. Mobitz II AV block usually occurs at or below the His-Purkinje system. It often develops into a complete AV block.

Grade 3 AV block, or complete AV block, can be acquired and congenital.

total systemic lupus erythematosus.

Clinical picture

Grade 1 AV block is usually asymptomatic.

• With the lengthening of the PQ I interval, the heart tone becomes quieter, therefore, a quiet I tone is characteristic of 1st degree AV blockade, with Mobitz I type II AV block, the volume of the I tone decreases from cycle to cycle, and with complete AV block it is different all the time.

• With complete AV block, a functional mesosystolic murmur may occur.

Etiology

The reasons for AV block are given in the table. The most common cause is an isolated disease of the conducting system (Lenegra's disease). In addition, AV block can occur in myocardial infarction, usually in the first 24 hours. It occurs in patients with inferior myocardial infarction and in 2% of patients with anterior infarction.

• Digoxin
• Beta-blockers
• Some calcium antagonists
• Antiarrhythmics with quinidine-like action

• Infective endocarditis
• Myocarditis (Chagas disease, Lyme disease, rheumatism, tuberculosis, measles, mumps)

• Primary adrenal insufficiency

• Heart surgery
• Radiation of the mediastinum
• Cardiac catheterization
• Catheter destruction

• Carotid sinus syndrome
• Vasovagal reactions

Diagnostics

1st degree AV block

This diagnosis is made with a PQ interval of more than 0.20 s in adults and more than 0.18 s in children. Each P wave is followed by a QRS complex, the shape of the P wave and QRS complex is normal.

2nd degree AV block

Mobitz I type 2 AV block is placed if the following symptoms are present:

• The PQ interval gradually lengthens, and then after the next P wave, the QRS complex falls out.

• The PQ interval gradually lengthens, but with each cycle by an ever smaller amount, so that the RR interval from cycle to cycle becomes shorter until the next ventricular complex falls out.

• The pause at the end of the Wenckebach period is less than any two consecutive RR intervals.

• The PQ interval after the pause is less than the PQ interval before the pause.

• QRS complexes form groups called Wenckebach periods.

Mobitz II type 2 AV block is less common than Mobitz I. It is characterized by the following symptoms:

• The PQ interval is the same all the time, but some of the atrial impulses are not delivered. In this case, in contrast to blocked atrial extrasystoles, the PP interval is constant.

• With advanced AV block, there is more than one P wave for each QRS complex (this is called AV block with conduction 3: 1, 4: 1, etc.). The QRS complexes are often wide (in contrast to the Mobitz I blockade, which is characterized by narrow complexes).

Complete AV block

AV-dissociation is characteristic, that is, the complete absence of time dependence between the P waves and QRS complexes. The P waves can be used to calculate the frequency of the atrial rhythm.

Treatment

No treatment is required for Grade 1 and Grade 2 AV block. For 2 nd degree AV block like Mobitz II and complete AV block, permanent pacemaker is usually indicated.

• Atropine can reduce AV block if it is due to an increase in parasympathetic tone, but not ischemia.

• Atropine is more effective in AV block with lower than with anterior myocardial infarction.

• Atropine does not affect conductivity in the Hisa-Purkinje system and therefore is ineffective for complete AV blockade, as well as for 2nd degree AV block caused by blockade at the level of the Hisa-Purkinje system.

• Atropine does not affect the transplanted heart.

• For Mobitz II-degree AV block, atropine should be used with caution because it may decrease the ventricular rate. Thus, AV block with 2: 1 conduction at an atrial rate of 80 beats per minute can turn into a 3: 1 AV block at an atrial rate of 90 beats per minute, as a result of which the ventricular rate will drop from 40 to 30 beats per minute.

Antidigoxin (Fab fragments of antibodies to digoxin) is used for hemodynamically significant AV block caused by digoxin. The dose is calculated as follows:

Number of vials \u003d Weight (kg) × Serum digoxin concentration (ng / ml) ⁄ 100

Complete AV block in inferior myocardial infarction is often transient, so a temporary pacemaker is usually sufficient.

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1 degree atrioventricular (AV) block - what it is and how to treat it

1st degree atrioventricular block is a pathological (less often physiological) symptom, which is determined on an electrocardiogram, reflecting a violation of the conduction of a nerve impulse through the conducting system of the heart.

To understand what this condition is and how to treat 1st degree AV block, it is necessary to explain that the heart has a conducting system with a clear hierarchy. The AV node (Ashoff-Tavara node) is located in the interatrial septum and is responsible for carrying the signal to contraction from the atria to the ventricles.

Epidemiology

Grade 1 AV block is quite common. The incidence increases in direct proportion to age, since over time the risk of developing heart disease (especially coronary heart disease) increases significantly.

There is evidence that AV block of the 1st degree is observed in 5% of people with cardiac disorders. As for children, their frequency of occurrence varies from 0.6 to 8%.

Classification

By the frequency and frequency of development:

• persistent - is identified and retained in the future;
• transient (transient) - was discovered once, but later disappeared;
• intermittent - passed after definition, but then reappeared.

According to the localization of the block for conducting AV blockade, they are divided into:

• proximal (violation in the part of the node closest to the atria);
• distal (the part close to the ventricles is affected);
• Combined blockades are encountered.

By predictive value

• Relatively favorable: functional grade 1 proximal AV block;
• Favorable: complete acute blockade, with QRS expansion (distal block).

Causes of AV block

The causes of the disease can be divided into organic and functional.

There are also a number of syndromes in which isolated AV node and His bundle degeneration is noted.

1) At the first, there is a partial anatomical (structural) lesion of the conducting system. This is observed, for example, when the node is involved in fibrosis after myocardial injury, with myocarditis, coronary artery disease, Lyme disease. Congenital ab-blockade is rare (children suffer from mothers with SSTD). Often the AV node is involved in inferior myocardial infarction.

2) With functional blockade, the morphology of the node is not disturbed, only the function suffers, which, of course, is better amenable to correction.

This condition occurs with the predominance of the tone of the parasympathetic nervous system, the use of antiarrhythmics (beta-blockers - bisoprolol, atenolol; calcium channel blockers - verapamil, diltiazem; glycosides - korglikon, strophanthin), electrolyte disturbances (hyper- / hypokalemia).

It should also be said that normally grade i AV block can also occur, and treatment is not required. This happens, for example, with professional athletes, young people.

3) Degenerative changes in the AV node in genetic pathology.

They develop with mutations of the gene encoding the synthesis of proteins of sodium channels of cardiomyocytes.

The following syndromes are specific: Leva, Lenegra, idiopathic calcification of the node.

Manifestations

What is heart block? In this case, the diagnostic ECG criterion for this condition is the lengthening of the PQ interval by more than 0.2 seconds, while the P waves are normal, the QRS complexes do not fall out.

Clinically, this state does not manifest itself in any way, since the heart contracts correctly, although less often than normal.

Therefore, this finding on the ECG does not indicate the need for treatment, rather, monitoring of the condition is necessary.

Symptoms may appear when triggered - physical. load. When syncope attacks (fainting), dizziness appear, one should suspect the transition of the blockade to the second degree (the next stage).

Patient monitoring program

In order to notice the progression of an incomplete blockade in time and start correcting it in time, the following is shown:

• repeated ECG - studies (the frequency is determined by the doctor);
• daily (Holter) ECG monitoring.

Of course, the ECG provides comprehensive information about rhythm disturbances, which is the 1st degree AV block. But in order to identify the causes, additional studies, for example, echocardiography, will be useful. Determination of the concentration of taken medications in the blood, the study of the ionic composition of blood can be diagnostically important.

Treatment

Grade 1 AV block does not require medical treatment. The dynamic control over the state of such people is shown. However, if the cause is identified and can be eliminated, it must be done.

With the development of pathology as a result of taking drugs - reduce the dose or cancel the drug with the selection of another, in the case of electrolyte disturbances - correction of the electrolyte balance. Summing up, we can say that functional AV block of the 1st degree can and should be influenced; in case of organic lesion of the node, a wait-and-see tactic should be chosen.

With a proven blockade of the functional type, the tone of the autonomic innervation can be carefully adjusted. Used drugs such as belloid, teopek.

Features in children

Violations of impulse conduction through the heart in children are quite common. This is due to the pathology of pregnancy that arose as a result of maternal diseases (diabetes mellitus, SLE), the effects of environmental factors, etc.

Heart rate is assessed differently in infants than in adults: heart rate is 100 bpm. is already considered bradycardia and requires attention. Therefore, first-degree AV block is noticeable at birth.

The following symptoms are noted: pallor or cyanosis, lethargy, weakness, breast refusal, increased sweating. At the same time, there may not be any clinical manifestations at grade 1.

Forecast

With functional disorders - favorable, with organic, probably a progressive course of pathology. Distal atrioventricular blocks are much more dangerous in terms of the risk of complications than proximal ones.

Prevention

There are no specific preventive measures for first-degree AV block.

As a measure of secondary prevention (prevention of progression), monitoring of the condition, implantation of a pacemaker (in case of deterioration) can be distinguished.

Atrioventricular block

Atrioventricular (atrioventricular) block (AV block) is a violation of conduction function, which is expressed in slowing down or stopping the passage of an electrical impulse between the atria and ventricles and leading to a disorder of the heart rhythm and hemodynamics. AV block may be asymptomatic or accompanied by bradycardia, weakness, dizziness, angina attacks, and loss of consciousness. Atrioventricular block is confirmed by electrocardiography, Holter ECG monitoring, and EFI. Treatment of atrioventricular blockade can be medication or cardiac surgery (implantation of a pacemaker).

Atrioventricular block

Atrioventricular blockade is based on a slowdown or complete cessation of the passage of an impulse from the atria to the ventricles due to damage to the AV node itself, the bundle of His or the legs of the bundle of His. Moreover, the lower the lesion level, the more severe the blockade manifestations and the more unsatisfactory the prognosis. The prevalence of atrioventricular block is higher among patients with concomitant cardiopathology. Among people with heart disease, grade I AV block occurs in 5% of cases, grade II - in 2% of cases, grade III AV block usually develops in patients over 70 years of age. Sudden cardiac death, according to statistics, occurs in 17% of patients with complete AV block.

The atrioventricular node (AV node) is part of the cardiac conduction system, which ensures consistent contraction of the atria and ventricles. The movement of electrical impulses coming from the sinus node slows down in the AV node, allowing the atria to contract and pump blood into the ventricles. After a short delay, impulses spread along the bundle of His and its legs to the right and left ventricles, contributing to their excitation and contraction. This mechanism provides alternate contraction of the atrial and ventricular myocardium and maintains stable hemodynamics.

Classification of AV blocks

Depending on the level at which the violation of the electrical impulse conduction develops, proximal, distal and combined atrioventricular blocks are distinguished. In case of proximal AV block, impulse conduction may be impaired at the level of the atria, AV node, bundle branch; with distal - at the level of the branches of the His bundle; with combined - there are multilevel conduction disturbances.

Taking into account the duration of the development of atrioventricular blockade, it is distinguished acute (with myocardial infarction, drug overdose, etc.), intermittent (intermittent - with coronary artery disease, accompanied by transient coronary insufficiency) and chronic forms. According to electrocardiographic criteria (deceleration, frequency or complete absence of impulse conduction to the ventricles), three degrees of atrioventricular block are distinguished:

• I degree - atrioventricular conduction through the AV node is slowed down, but all impulses from the atria reach the ventricles. Not clinically recognized; on the ECG, the P-Q interval is extended\u003e 0.20 seconds.
• II degree - incomplete atrioventriular block; not all atrial impulses reach the ventricles. ECG shows periodic prolapse of ventricular complexes. There are three types of Mobitz II degree AV block:

1. Type I Mobitz - the delay of each subsequent impulse in the AV node leads to a complete delay of one of them and the loss of the ventricular complex (Samoilov-Wenckebach period).
1. Mobitz type II - a critical impulse delay develops suddenly, without a previous lengthening of the delay period. In this case, the absence of every second (2: 1) or third (3: 1) impulse is noted.

• III degree - (complete atrioventricular block) - complete cessation of the passage of impulses from the atria to the ventricles. The atria contract under the influence of the sinus node, the ventricles - in their own rhythm, at least 40 times per minute, which is not enough to ensure adequate blood circulation.

Atrioventricular blockade I and II degrees are partial (incomplete), block III degree - complete.

Reasons for the development of AV blocks

By etiology, functional and organic atrioventricular blocks are distinguished. Functional AV blocks are caused by an increase in the tone of the parasympathetic part of the nervous system. Atrioventricular block I and II degrees in isolated cases is observed in young physically healthy individuals, trained athletes, pilots. It usually develops during sleep and disappears during physical activity, which is explained by the increased activity of the vagus nerve and is considered a variant of the norm.

AV blockade of organic (cardiac) genesis develops as a result of idiopathic fibrosis and sclerosis of the cardiac conduction system in various diseases. The causes of cardiac AV blockade can be rheumatic processes in the myocardium, cardiosclerosis, syphilitic heart disease, interventricular septal infarction, heart defects, cardiomyopathy, myxedema, diffuse connective tissue diseases, myocarditis of various origins (autoimmune, diphtheria, thyroid-toxic, hemoarcoidosis), , heart tumors, etc. With cardiac AV block, a partial block may initially be observed, however, as the cardiopathology progresses, a III degree block develops.

Various surgical procedures can lead to the development of atrioventricular blockades: aortic valve replacement, plastic surgery of congenital heart defects, atrioventricular RFA of the heart, catheterization of the right heart, etc.

A congenital form of atrioventricular block (1: newborns) is quite rare in cardiology. In the case of congenital AV blocks, there is a lack of sections of the conducting system (between the atria and the AV node, between the AV node and the ventricles or both legs of the bundle of His) with the development of the corresponding level of blockade. In a quarter of newborns, atrioventricular block is combined with other cardiac anomalies of a congenital nature.

Among the reasons for the development of atrioventricular blockades, intoxication with drugs is often found: cardiac glycosides (digitalis), β-blockers, calcium channel blockers (verapamil, diltiazem, less often corinfar), antiarrhythmics (quinidine), lithium salts, and some other drugs.

Symptoms of AV block

The nature of the clinical manifestations of atrioventricular blockade depends on the level of conduction disturbance, the degree of blockade, etiology and severity of concomitant heart disease. Blockades that have developed at the level of the atrioventricular node and do not cause bradycardia do not manifest themselves clinically. The clinic of AV blockade with this topography of disorders develops in cases of severe bradycardia. Due to a low heart rate and a drop in the cardiac output of blood under conditions of physical exertion, such patients have weakness, shortness of breath, and sometimes angina attacks. Dizziness, transient confusion, and fainting may occur due to decreased cerebral blood flow.

With atrioventricular block II degree, patients feel the loss of the pulse wave as interruptions in the heart. With AV block of type III, attacks of Morgagni-Adams-Stokes occur: a decrease in the pulse rate to 40 or less beats per minute, dizziness, weakness, darkening in the eyes, short-term loss of consciousness, pain in the heart, cyanosis of the face, possibly convulsions. Congenital AV block in pediatric and adolescent patients may be asymptomatic.

Complications of AV block

Complications in atrioventricular blockages are mainly due to a pronounced slowdown in the rhythm that develops against the background of organic damage to the heart. Most often, the course of AV block is accompanied by the appearance or aggravation of chronic heart failure and the development of ectopic arrhythmias, including ventricular tachycardia.

The course of complete atrioventricular block may be complicated by the development of Morgagni-Adams-Stokes attacks associated with brain hypoxia as a result of bradycardia. The onset of an attack may be preceded by a feeling of heat in the head, bouts of weakness and dizziness; during an attack, the patient turns pale, then cyanosis and loss of consciousness develops. At this point, the patient may require chest compressions and mechanical ventilation, since prolonged asystole or the addition of ventricular arrhythmias increases the likelihood of sudden cardiac death.

Multiple episodes of loss of consciousness in elderly patients can lead to the development or aggravation of intellectual and mnestic disorders. Less commonly, with AV block, arrhythmogenic cardiogenic shock may develop, more often in patients with myocardial infarction.

In conditions of insufficient blood supply in AV block, the phenomena of cardiovascular failure (collapse, fainting), exacerbation of ischemic heart disease, and kidney disease are sometimes observed.

Diagnostics of AV blockade

When assessing the patient's history, in case of suspicion of atrioventricular blockade, they find out the fact of past myocardial infarction, myocarditis, other cardiopathologies, taking drugs that violate atrioventricular conduction (digitalis, β-blockers, calcium channel blockers, etc.).

With auscultation of the heart rhythm, the correct rhythm is heard, interrupted by long pauses, indicating a loss of ventricular contractions, bradycardia, the appearance of the cannon I tone of Strazhesko. An increase in the pulsation of the cervical veins compared with the carotid and radial arteries is determined.

On the ECG, grade I AV block is manifested by lengthening the P-Q interval\u003e 0.20 sec; II degree - sinus rhythm with pauses, as a result of prolapse of ventricular complexes after the P wave, the appearance of Samoilov-Wenckebach complexes; III degree - a decrease in the number of ventricular complexes by 2-3 times compared with atrial complexes (from 20 to 50 per minute).

Daily Holter ECG monitoring in case of AV block allows comparing the patient's subjective sensations with electrocardiographic changes (for example, fainting with severe bradycardia), assessing the degree of bradycardia and blockade, the relationship with the patient's activity, taking medications, determining the presence of indications for implantation of a pacemaker, etc.

With the help of electrophysiological examination of the heart (EPI), the topography of the AV block is clarified and the indications for its surgical correction are determined. In the presence of concomitant cardiopathology and to identify it with AV block, echocardiography, MSCT or MRI of the heart are performed.

Additional laboratory tests for AV block are indicated in the presence of concomitant conditions and diseases (determination of the level of electrolytes in the blood during hyperkalemia, the content of antiarrhythmics during their overdose, enzyme activity during myocardial infarction).

AV block treatment

With atrioventricular block of the 1st degree, proceeding without clinical manifestations, only dynamic observation is possible. If the AV block is caused by taking medications (cardiac glycosides, antiarrhythmic drugs, β-blockers), dose adjustment or their complete cancellation is necessary.

In case of AV blockade of cardiac origin (with myocardial infarction, myocarditis, cardiosclerosis, etc.), a course of treatment with β-adrenostimulants (isoprenaline, orciprenaline) is carried out, further implantation of a pacemaker is indicated.

First aid drugs for the relief of Morgagni-Adams-Stokes attacks are isoprenaline (sublingual), atropine (intravenous or subcutaneous). With symptoms of congestive heart failure, diuretics, cardiac glycosides (with caution), vasodilators are prescribed. As symptomatic therapy for chronic AV blockade, treatment with theophylline, belladonna extract, nifedipine is carried out.

A radical method of treating AV blockade is the installation of a pacemaker (pacemaker), which restores the normal rhythm and heart rate. The indications for the implantation of an endocardial pacemaker are a history of Morgagni-Adams-Stokes attacks (even a single one); ventricular rate less than 40 per minute and periods of asystole 3 or more seconds; AV block II degree (type II according to Mobitz) or III degree; complete AV block, accompanied by angina pectoris, congestive heart failure, high arterial hypertension, etc. Consultation of a cardiac surgeon is required to resolve the issue of surgery.

Prediction and prevention of AV blockade

The influence of the developed atrioventricular blockade on the future life and work ability of the patient is determined by a number of factors and, first of all, by the level and degree of blockade, the underlying disease. The most serious prognosis for grade III AV block: patients are disabled, the development of heart failure is noted.

The prognosis is complicated by the development of distal AV blockages due to the threat of complete blockade and a rare ventricular rhythm, as well as their occurrence against the background of acute myocardial infarction. Early implantation of a pacemaker can increase the life expectancy of patients with AV block and improve their quality of life. Complete congenital atrioventricular blocks are prognostically more favorable than acquired ones.

As a rule, atrioventricular block is caused by the underlying disease or pathological condition, therefore, its prevention is the elimination of etiological factors (treatment of cardiac pathology, exclusion of uncontrolled intake of drugs that affect the conduction of impulses, etc.). To prevent the worsening of the degree of AV blockade, implantation of a pacemaker is indicated.

Atrioventricular block - treatment in Moscow

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Heart block treatment

The supply of oxygen to all tissues and organs occurs thanks to the heart, which creates pressure and pumps blood. In this case, the heart muscle should contract about 55 to 80 times in 60 seconds. The whole body depends on the rhythm of the heartbeat.

If the intervals between contractions are equal, then the cells regularly and continuously receive the required amount of oxygen and all processes in the body remain normal, but due to the slightest disruption in the work of the cardiovascular system, tissue hypoxia occurs, which turns into more problematic pathologies. Very often, a heart block becomes the cause of a lack of oxygen in the brain and other organs.

How does pathology appear and what is it?

The origin of the impulse occurs due to the sinus node, which sets the rhythm. The impulse moves to the atria and, as a result of their contractions, is transmitted to the bundles and nodes of the system. After that, the wave moves along the smallest channels of the body and Purkinje fibers.

Interruption of this process leads to a delay in the impulse in certain areas and leads to various diseases. Blockages are called pathologies that relate to heart rhythm disturbances - to arrhythmias.

Sometimes, myocardial conduction is completely isolated by the blockade. And also blockades can be combined with different types of arrhythmias or be combined with other blockades. Most often, blockages develop in older people, less at a young age.

The main danger of a blockade is a delay in myocardial contractions, which can vary from a tenth of a second to a whole minute or more. Subsequently, the person may have oxygen starvation, fainting and clinical death.

Heart block symptoms and treatment - it all depends on the individual organism. The deterioration of the condition will also depend on the cause of the blockade and the place of appearance in the conducting system. Pulse blocking can occur both in the atrium and in one of the ventricles.

Types of blockades

An important indicator in the diagnosis and treatment of the disease is the severity of the violation of the passage of excitability. For this factor, pathology is divided into the following types:

• blockade of 1 degree - poor passage, but an excitation pulse is carried out;
• blockade of the 2nd degree - the complete cessation of the passage of the impulse to the ventricles, which is very dangerous and often leads to death.

Pathology is distinguished by the place of education:

• sinotrial block - affects the sinus node;
• atrial block - impaired impulse in the atrium;
• interatrial - interruption of the impulse on the way to the left atrium from the sinoatrial node;
• transverse or atrioventricular - a violation during the transition of the impulse to the ventricles from the atrium;
• intraventricular - blockade of the lower part of the left or right leg of His.

In turn, intraventricular pathology is divided into the following types:

• interventricular - the pathways of the ventricular septum are affected;
• right ventricular block - interruption of the impulse in the anterior or posterior branch of the left leg of His;
• left ventricular block - interruption of the impulse anywhere in the left leg of His;
• left ventricular block.

Types of pathology by time of appearance:

Factors in the appearance of blockades

A partial blockage can occur in a healthy person without causing any harm. For example, small heart anomalies can lead to the appearance of a partial blockade of the right branch of the His, which does not develop further and does not change its position.

Blockade of the first degree can appear in young people due to intense sports activities or strenuous physical work. In some cases, heart block may be congenital.

Such a pathology appears in violation of intrauterine development. In this case, a defect of the heart valve and other disorders of the cardiovascular system are observed, which are found in a child immediately after his birth.

Causes of blockades

There are a number of main causes of pathology:

• autoimmune disease;
• thyrotoxicosis;
• diphtheria;
• myocarditis;
• vasculitis;
• acquired heart disease;
• tumor or metastasis of the myocardium;
• myxedema;
• sarcoidosis;
• amyloidosis;
• heart attack;
• fibrosis;
• hypertension;
• violation of metabolic processes;

And there is also the likelihood of blockages from taking glycosides, antiarrhythmic drugs, beta-blockers. Pathology can appear after surgery, as well as complicate various types of operations. Myocardial conduction is impaired from drug use and alcohol overdose.

Symptoms of the manifestation of pathology

In most cases, mild degrees of the disease do not cause any discomfort in a person.

Partial blockages are only detected with a cardiogram, routine health check-up or routine check-up.

However, incomplete heart block presents a risk of possible complications. Sinoauricular blockade, when the impulse stops or slows down, the patient feels pain in the chest area, suffers from shortness of breath, weakness, decreased performance and dizziness.

And in such cases, when the impulse often slows down, stops, with a complete blockage of the heart, the person has a feeling of cardiac arrest, frequent dizziness, accompanied by tinnitus and passing into a fainting spell.

Pronounced symptoms appear with a complete blockade of the heart of the AV node. Such blockages are manifested by arrhythmia and bradycardia, and can also show signs of an underlying heart disease.

There are cases when, when a person feels normal, he suddenly has arrhythmia. If the deterioration in the body lasts a long time, then the person adapts and feels good.

The patient may have seizures against the background of blockades. They are distinguished by the level of the patient's condition:

• mild form - a person does not lose consciousness, but suffers from dizziness, feels tinnitus, limbs go numb;
• moderate severity - the patient may lose consciousness, while there are no seizures, urination does not occur;
• severe form - a mild and medium form of an attack is combined. Without action, it can be fatal.

Such seizures often occur in people with atrioventricular block. The attack can be repeated, and the frequency of repetitions and the gap between them depends on the organism.

Indicators of serious conduction disturbances

When the heartbeat slows down to 50 beats per minute, the person complains of dizziness. And there are also other symptoms of blockages:

• the person gets tired quickly;
• physical activity is felt in a greater equivalent;
• unpleasant sensation in the chest area;
• playing sports brings pain in the chest;
• pain in a calm state;
• short-term cardiac arrest;
• darkening in the eyes;
• sudden weakness and dizziness;
• nausea;
• feeling of noise and ringing in the ears;
• headache, mostly in the occiput.

If a child is born with a pulse of less than 80 beats per minute, then he is given a cardiogram. The pulse rate in children should be higher than that of adults. In this case, the complete blockade is confirmed or refuted. This pathology is sometimes found in utero.

With atrioventricular block, the child is pale, with a slow heartbeat and is lagging behind in development. And also may refuse to feed. Subsequently, insufficient blood circulation in the baby often faints, convulsions and seizures. With a prolonged attack, breath holding and cardiac arrest are possible. Congenital blockage can be the cause of the death of a child in the early stages of life.

Blockade diagnostics

When symptoms of the disease appear, the doctor can learn about violations when decoding analyzes and examining a patient. By listening to the work of the heart, the doctor can determine irregularities in the heartbeat, as well as heart failure characteristic of some. Most often, the disease is diagnosed by means of electrocardiograms, thanks to which it is possible to accurately determine the type of disease.

To determine the blockade, a one-time electrocardiogram is not enough, the procedure may be ineffective. To obtain more accurate results, it is recommended to conduct a Holter examination.

Such a procedure is performed within 24 hours, and the result of the procedure is information about transient blockages, heart rhythm problems. In patients, heart block is often checked on an ECG with stress, which allows you to establish the level of permissible physical activity and the class of heart failure. Other methods of examination are also used to detect the causes of pathology:

Various laboratory tests and other studies may be required to obtain accurate information.

Treatment with medication

With the help of medications, heart block can be treated and the heart rhythm restored. In this case, an effect on the pathology itself occurs. With a partial block, most often the patient only needs observation and a healthy regimen.

If the pathology began as a result of an overdose or prolonged use of drugs, they must be canceled immediately. Sometimes, for myocardium caused by an autoimmune disease, antibiotics, NSAIDs, glucocorticosteroids and statins may be required.

Drug therapy includes taking such drugs:

• beta blockers - Betalok;
• beta adrenostimulants - Isoprenaline or Orciprenaline;
• diuretic - Furosemide;
• vasodilator - Amlodipine;
• antiarrhythmic drugs - Quinidine;
• calcium channel blocker - Corinfar and Nifedipine;
• antihypertensive substance - Perindopril and Enalapril.

Surgical intervention for blockages

Unfortunately, in contrast to partial blockages, some types of blockages cannot be cured with medication. In such cases, the only way out with positive results is surgery.

When a patient has heart attacks, pacemakers are most often installed. There are also some factors that require continuous use of a pacemaker:

• a big difference in the decrease in heart rate;
• a combination of a complete blockade with ectopic arrhythmia, heart failure and other heart diseases;
• impaired conductivity and hemodynamics at the same time;
• asystole that lasts up to 2 seconds.

For heart attack or other serious complications, a temporary pacemaker may be inserted.

Power mode during blockages

The diet and products consumed by the patient are of great importance for any type of blockade related to the passage of the impulse. It is recommended to eat foods that contain potassium, calcium, magnesium and other minerals that nourish the myocardium. The patient's condition is positively influenced by the use of products with useful minerals:

In the patient's diet, it is necessary to include more plant products in which there are more vitamins, as well as limit the consumption of salty, fatty and sweet foods.

Prevention of pathology

Most often, first-degree heart block becomes a complication of the underlying heart disease. Therefore, preventive measures are to treat heart failure immediately after the detection of symptoms of pathology. In this case, it is necessary to monitor the dosage of the medication taken to prevent overdose, as well as to stop using harmful substances.

Assisting with the blockade

Blockages can develop and proceed with complications. At the same time, the occurrence of seizures predisposes to knowledge of first aid and further actions. The patient should be placed on a flat surface with a small pillow under his head. An Isadrin tablet is placed under the patient's tongue, and in case of loss of consciousness, take action and bring the patient to life.

In the absence of pulse and respiratory arrest, perform indirect myocardial massage and artificial respiration. Providing such assistance before an ambulance arrives can save a person's life.

With an elevated cholesterol level and a tendency to be overweight, it is necessary to take measures to lose weight, since the load on the heart also depends on the weight of the human body.

With blockages of any type, smoking and alcohol abuse are prohibited. You need to lead a healthy lifestyle. Your life schedule needs to be replenished with moderate exercise. Children with congenital or acquired complete blockages cannot live like their peers.

They cannot serve in the army and perform heavy physical activity, attend sports sections and clubs. Pregnancy with blockages needs to be planned, while doctors will decide on an individual basis whether carrying is possible.

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The cause of AV blockages can be isolated disease of the conducting system (Lenegra's disease), myocardial infarction (blockade, as a rule, manifests itself in this case in the first 24 hours), coronary heart disease (IHD), congenital and acquired heart defects, long-term hypertension, cardiosclerosis, some endocrinological diseases, etc. The causes of AV blockages can also be functional (taking certain types of medications, intense sports).

Functional causes of AV heart block, such as taking β-blockers, cardiac glycosides (digitalis), antiarrhythmic drugs (quinidine), intravenous administration of drotaverine and papaverine, calcium channel blockers (diltiazem, verapamil, corinfaroma), lithium mud, can be eliminated by refusal from taking medications. In general, the functional causes of the onset and development of AV blockages are caused by an increase in the tone of the parasympathetic part of the nervous system.

The causes of AV block in children are congenital heart defects and certain diseases of the mother during pregnancy (for example, systemic lupus erythematosus in the mother). Often the congenital form of atrioventricular block in children is caused by the absence of sections of the conducting system (between the AV node and the ventricles, between the atrium and the AV node, between both legs of the His).

Causes of AV block of 1 degree

Atrioventricular block 1 and 2 degrees in isolated cases is observed in young trained people (athletes, pilots, military, etc.). The cause of AV block of the 1st degree in this case is the increased activity of the vagus nerve - the blockade manifests itself, as a rule, in sleep and disappears during physical activity. Such a manifestation of it is considered as a variant of the norm and does not require treatment.

The reason for the appearance of AV block of the 1st degree may be the use of drugs that reduce the heart rate (HR). Such drugs should be taken with caution when AV block appears. The disease itself (deviation) can only be detected on an electrocardiogram (ECG).

Causes of AV blockade 1 tbsp. without background myocardial damage are not sought, treatment is not prescribed, however, the patient is recommended to undergo a regular medical examination, because the disease tends to progress. In most cases, AV block 1 tbsp. is transient (transient), clinically does not manifest itself, and its cause may be vegetative-vascular dystonia of the hypotonic type.

The causes of transient AV blockade are often the abuse of medications, including their incorrect combination with each other. Increased physical activity leading to increased activity of the vagus nerve is also the cause of transient AV block during sleep.

Causes of AV blockade 2 degrees Mobitz type I and II

At the heart of AV blockade is 2 tbsp. Mobitz I and II types often lie organic diseases:

• Ischemic heart disease - with ischemia, the myocardium experiences a prolonged lack of oxygen (hypoxia), in connection with which microscopic areas of tissue appear that do not conduct electrical impulses (and do not fully contract). If such foci are concentrated near the borders of the atria and ventricles, an obstacle appears in the path of impulse propagation - a blockade arises and develops;
• myocardial infarction (acute and subacute) - a similar mechanism, but areas of dead tissue also appear;
• heart defects (congenital or acquired) - a serious violation of the structure of muscle fibers, leading to structural changes in the chambers of the heart, cardiomyopathies;
• arterial hypertension (long-term) - leads to hypertrophic or obstructive left ventricular cardiomyopathy.

The causes of atrioventricular blockade of the 2nd degree can also be in isolated diseases of the cardiac conduction system - Lenegra's disease and Lev's disease, calcification of the valve rings, infiltrative myocardial diseases - amyloidosis, sarcoidosis, hemochramosis. The cause of congenital AV block 2 tbsp. can become systemic lupus erythematosus in the mother. Congenital heart defects - an atrial septal defect of the ostium primum type and transposition of the main arteries - can also cause stage 2 AV block. Mobitz 1 and 2 types.

Inflammatory diseases also become causes of 2nd degree AV blockade: infective endocarditis, myocarditis (Lyme disease, Chagas disease, rheumatism, measles, tuberculosis, mumps). Endocrinological diseases such as diabetes mellitus (especially type 1), hypothyroidism, as well as gastric ulcer, primary adrenal insufficiency are also the reasons for the appearance of 2nd degree AV block.

The causes of 2nd degree AV block can be: metabolic disorders - hyperkalemia, hypermagnesemia, damage to the AV node during heart operations, cardiac catheterization, catheter destruction, mediastinal radiation, neuromuscular diseases (for example, atrophic myotonia). The causes of 2nd degree AV block can be craniocerebral trauma, intoxication and poisoning, infectious diseases, and fevers.

Tumors (mesothelioma, melanoma, lymphogranulomatosis, rhabdomyosarcoma), collagenoses (rheumatoid arthritis, systemic scleroderma, systemic lupus erythematosus, Reiter's syndrome, ankylosing spondylitis, polymyositis) can also act as causes of stage 2 AV block. Neurogenic causes of transient and permanent grade 2 AV block in young and old people can be triggered by diseases such as carotid sinus syndrome or vasovagal reactions.

In general, the causes of 2nd degree AV block are the development of idiopathic fibrosis and sclerosis of the cardiac conduction system in various diseases. This also includes a whole list of diseases associated with rheumatic processes in the myocardium, syphilitic damage to the heart, cardiosclerosis, interventricular septal infarction, diffuse connective tissue diseases.

Regardless of the causes of 2nd degree AV block, treatment, as a rule, boils down to the installation of a pacemaker. Medication is not self-administered. In rare cases - when medication is the cause of the disease - treatment is reduced to drug withdrawal.

Causes of complete AV block (grade 3)

The causes of grade 3 AV block (complete block) are the same as grade 2. Not infrequently AV block 2 tbsp. goes into a complete blockade. Treatment - installation of a pacemaker.

Ailments of the heart and blood vessels are now found especially often among the population of different ages. Such diseases pose a serious threat to health and even life, and are provoked by a variety of factors, including congenital predisposition, and improper lifestyle, and pathological effects of other diseases. One of the fairly common ailments of the cardiovascular system is considered to be atrioventricular blockade, which may differ in severity. In short, this condition is called simply av blockade, we will consider the ailment of the 1st, 2nd and 3rd degrees in more detail, and also discuss its treatment and talk about how prevention is carried out.

About what kind of AV blockade is (degree of condition)

AV block is a form of blockade of conducting a natural electrical impulse through the atrioventricular node located between the atria and ventricles. There are three degrees of such a pathological condition, depending on whether the electrical impulse is carried out slowly, periodically, or completely blocked.

With AV block of the first degree, each impulse from the atria reaches the ventricles, but its conduction is delayed literally for a fraction of a second - at the time of passage through the atrioventricular node. Such a pathological condition does not make itself felt in any way. It occurs in highly trained athletes as well as adolescents and young adults who have high vagus nerve activity. In addition, 1st degree AV block can occur against the background of rheumatism, heart damage, sarcoidosis, etc.

AV block of the 2nd degree is manifested by the fact that not every impulse reaches from the atria to the ventricles. In this case, a rare and often irregular contraction of the heart is observed. Sometimes this blockade will eventually transform into a grade 3 blockade.

With AV block of 3 degrees, the conduction of the natural impulse from the atria to the ventricles completely stops. The heart rate, as well as the heart rate, are set at the same time by the atrioventricular node or directly by the ventricles. The lack of natural stimulation by the sinus node leads to the fact that ventricular contraction occurs very rarely - less than forty times per minute. Thus, grade 3 AV block is a dangerous arrhythmia that can negatively affect the pumping function of the heart. At the same time, the patient experiences fainting, dizziness and heart failure. In the event that the contraction of the ventricles occurs more than forty times per minute, the symptoms are less serious, however, patients are tormented by fatigue, hypotension (during the lifting of the trunk), as well as shortness of breath.

How AV block is corrected (treatment)

If a patient has 1 degree AV block, which is not accompanied by negative symptoms, he is shown only dynamic observation. In the event that the violation is triggered by the consumption of medicines, for example, cardiac glycosides, anti-arrhythmia drugs or beta-blockers, it is important to adjust their dosage or completely cancel them.

Second-degree AV block requires treatment of the disease, and third-degree ailment is an occasion for serious observation and prolonged therapy.

If AV blockades are of cardiac origin (developed against the background of a heart attack, myocarditis, cardiosclerosis, etc.), the patient is prescribed therapy with beta-adrenostimulants, for example, isoprenaline or orciprenaline. Over time, a pacemaker is implanted.

First aid drugs (if necessary, to stop the attacks of Morgagni-Adams-Stokes) are izadrin or atropine. The first is administered sublingually, and the second is administered subcutaneously. To correct the phenomena of congestive heart failure, diuretics are used, as well as cardiac glycosides (only with caution) or vasodilators. For symptomatic treatment, medications such as theopeca, belloid, and corinfar are commonly used.

A radical method of therapy for AV blockade is the installation of the so-called pacemaker. Such surgery helps to restore the normal rhythm as well as the heart rate. The decision on surgical correction is made after consultation with a cardiac surgeon.

How AV block is prevented (prevention)

The main preventive measure for AV blockade is systematic observation by a cardiologist, especially in old age. Such monitoring implies, first of all, the removal of an ECG - electrocardiogram, as well as monitoring the heart rate in case of any suspicion of any violations. Prevention of AV blockade also implies maintaining a healthy lifestyle, giving up bad habits, as well as proper nutrition, rich in potassium and magnesium.

Additional Information

The prognosis for patients with AV block depends on the extent of the disorder and the type of underlying disease. The most serious prognosis is typical for patients with grade 3 AV block. Such patients are disabled and develop heart failure.

At the same time, early implantation of a special pacemaker makes it possible to increase the life expectancy of patients with such a diagnosis by an order of magnitude, and also significantly improve their quality of life. Also, timely implantation helps to prevent the worsening of the degree of AV blockade.

Ekaterina, www.site

P.S. The text uses some forms characteristic of oral speech.

In order for the heart to supply blood to every cell of the body, it must contract at the correct rhythm and with a frequency of 55-60 to 80-90 beats per minute. The rhythm should be regular, with equal intervals between contractions, because the lack of oxygen carried with the blood, even for more than 30 seconds, can already affect the functioning of cells, and first of all, brain cells. The onset of oxygen starvation (hypoxia) of the brain is especially important for conditions such as heart block.

Blockade II and III degree, complete intraventricular blockade, three-bundle blockade (both right and both branches of the left leg of His) almost always occur with organic damage to the heart tissue. Diseases that cause inflammatory or scarring processes in the myocardium include:

Prevention is competent medical treatment of the underlying disease, timely determination of indications for implantation of a pacemaker.

Forecast

The prognosis for blockade I degree in the absence of organic heart damage is favorable.
For complete blockages, the prognosis is determined by the nature of the underlying disease, the degree of dysfunction of the heart and the stage of chronic heart failure. The frequency and number of seizures of MES are not predictors of mortality, that is, they do not affect the prognosis - in some patients, seizures may occur frequently, while in others, a single seizure in a lifetime can be fatal.

The prognosis for patients in the acute period of myocardial infarction, complicated by the development of complete left or right His bundle blockade, is extremely unfavorable.

Physician therapist Sazykina O.Yu.