ECG of the heart is a violation of intraventricular conduction. Manifestations on the ECG. Features of a two-bundle blockade of the right leg with the left anterior branch

Let's consider the problems of slowing intraventricular conduction: what it is, what are the causes of development, how to treat. Every person should know the answer to these questions, since heart pathologies have no limitations. All of us are susceptible to heart disease. The heart is an organ without which life is impossible; it must be protected.

Exists certain time, during which the electrical impulse starting in the sinus node must reach the ventricular myocardium. If this time is disrupted, various complications in the functioning of the heart may occur. Slowing of intraventricular conduction is a pathology associated with a disturbance in the conduction of impulses along the pathways in the ventricles, the so-called bundles of His.

The danger is that if such impulses are completely blocked, then there is high probability cardiac arrest. In medicine, this process is called complete blockade. However, incomplete blockade is more often diagnosed when the impulse is carried out slowly. Slowing of intraventricular conduction in children Heart disease worries not only adults, but also children. Violations of intraventricular conduction of the heart are diagnosed even in infants. The main reasons for the development of pathology:

• birth injury;
• prematurity;
• Congenital heart defect;
• lack of oxygen for the myocardium;
• open oval window in heart;
• general intoxication of the body.

A slowdown in intraventricular conduction is manifested by a decrease in the heart rate and disturbances in ECG readings. Some children may experience heart pain, general weakness, and dizziness. Fixed sharp changes moods. For any manifestations of pathology, you must contact a cardiologist. Violations are often detected by chance during an examination using an ECG machine.

As for the danger of such a condition, the forecasts are different. In some children, the conduction disorder is not life-threatening, and symptoms go away as they get older. But if there is a complete blockade of a chronic nature, then the following complications are possible:

• fainting;
• ischemia of the heart muscle;
• heart failure;
• sudden cardiac arrest.

The cardiologist will first rule out all heart diseases, in which case the child does not need treatment. But if heart pathologies are detected, therapy will be aimed at eliminating the cause. On initial stage appointed drug therapy. If it turns out to be ineffective, then ventricular electrical stimulation is performed.

Reasons for the development of pathology

Slowing of conduction inside the ventricles is complete and incomplete blockade of the bundle branches. The disease develops in three stages. The first two often do not appear and are not expressed on the electrocardiogram (ECG). In the third stage, the pulse slows to 40 beats per minute or less. This condition is called "bradycardia". The ECG shows impaired ventricular function. This slowdown requires urgent medical adjustment.

There are many reasons for the development of pathology. Many patients do not seek treatment in a timely manner medical care, do not treat cardiovascular diseases, have bad habits. In everyone's life there are stresses that weaken the nervous system. All causes of violation are divided into three groups:

1. Organic.
2. Functional.
3. Medicinal.

Organic

Group organic reasons includes cardiovascular diseases, in which the structure of the entire cardiac conduction system changes. These include:

• myocarditis - inflammation of the heart muscle;
• myocardial infarction – necrosis ( irreversible change) area of ​​the heart muscle of an ischemic nature;
• myocardial hypertrophy – pathological growths and compactions;
• cardiac ischemia – insufficient blood circulation in the tissues of the heart (primarily in the myocardium);
• cardiosclerosis is a myocardial pathology characterized by the proliferation of connective scar tissue;
• cardiomyopathy - damage to the heart muscle of unknown origin, in which the size of the heart increases, heart failure develops, and heart rhythm and conduction are disrupted;
• violation of the bronchopulmonary system: asthma, obstructive bronchitis.

Functional

This group of reasons does not cause failures of cardio-vascular system. There is an imbalance of the sympathetic (responsible for increasing the heart rate) and parasympathetic (responsible for slowing the heart rate) systems. If their balance is disturbed, an abnormal heart rhythm is recorded.

Medicinal

Blockades that have arisen due to medicinal reasons are difficult to treat and differ from others in particular severity. Pathology occurs due to the use of drugs (antiarrhythmics) that affect heart rhythm and contractions.

Important! Blockage can also occur in completely healthy person, if there is a congenital open oval window in the heart.

Clinical picture

There are no independent signs of slowing intraventricular conduction. Symptoms depend on the disease that caused the rhythm disturbance. With this disorder the following symptoms are observed:

• shortness of breath at rest;
• frequent dizziness (impaired blood circulation in the brain);
• swelling of the lower extremities;
• sensations of heart sinking;
• feeling of lack of air, anxiety, fear;
• sudden mood swings;
• memory gaps;
• bradycardia – disturbance of sinus rhythm;
• falling out of the blue;
• general weakness, fatigue.

ECG readings will vary depending on the specific cardiovascular disease. Partial conduction disturbance may not be accompanied by any symptoms. Complete blockade is characterized by:

• slow heartbeat;
• pain in the heart area;
• loss of consciousness.

In case of severe heart pain, cold sweat, or malaise, the pulse can be felt slowly: less than 45-50 beats per minute. If the ECG shows a complete block, a heart attack may be developing. acute stage. This condition requires urgent hospitalization. If a person discovers any symptoms of slowed intraventricular conduction or they were detected on an ECG, it is necessary to urgently consult a doctor. Only he will be able to correctly decipher the cardiogram, which will help to promptly identify dangerous heart diseases.

Diagnosis of the disease

If any symptoms occur - dizziness, malaise, heart pain, fainting - you should contact a cardiologist. At the first appointment, the specialist collects the patient’s medical history: learns about all his chronic and previous diseases and operations, receives information about close relatives.

Measurement of pulse, pressure, listening and tapping (percussion) of the heart is carried out. Using such methods, it is possible to determine changes in the boundaries of the heart, rhythm and frequency of contractions. The doctor will definitely prescribe an ECG. For a more accurate diagnosis, blood tests, urine tests (general and biochemical), and hormone tests may be needed to exclude diseases not related to the cardiovascular system.

But one ECG may not show problems with conduction, then a number of other methods are used:

1. Electrography of the His bundles makes it possible to identify the blockade and clarify its localization.
2. Monitoring ECG using the Holter method is often used, carried out throughout the day and giving a general picture of the work of the heart, in particular, the conduction of impulses.
3. Bicycle ergometry is prescribed - a method of identifying the conductivity of impulses during physical activity.
4. Ultrasound examination (ultrasound) or echocardiography (ECHO), showing the anatomical structures of the heart and identifying possible diseases.
5. If ultrasound or ECHO provide insufficient information, then magnetic resonance imaging (MRI) is prescribed. This examination makes it possible to obtain accurate information about the heart and determine the condition of the blood vessels. Provides a three-dimensional image of the organ in different planes, which helps the doctor identify even the beginning of pathology

Treatment

If according to the results diagnostic studies no pathologies of the cardiovascular system have been identified, the cardiologist prescribes vitamins and medications that improve myocardial function. These include: “Preductal”, “Antisten”. If there is a complete blockade, the question arises about installing a pacemaker. As for elderly patients, hospitalization is required during the initial examination. Within the hospital there will be carried out necessary examinations. If a disease is detected that provokes a slowdown in intraventricular conduction, various methods therapy depending on the pathology, for example:

• for ischemia, coronary lytics are prescribed - antianginal drugs that improve blood supply to the myocardium by dilating the coronary arteries;
• inflammatory processes require a course of antibiotic or hormonal therapy;
• For chronic heart failure, diuretics are prescribed.

Effective treatment for slowing intraventricular conduction is only possible if the cause is eliminated. There will be no reason - the symptoms will disappear.

Possible complications

Advanced forms of intraventricular conduction lead to irreversible consequences. A partial blockade is not dangerous to health, but failure to consult a doctor in a timely manner can lead to it developing into a complete blockade.

With a complete blockade, the following complications are possible:

• heart failure;
• stroke;
• heart failure;
• bradycardia;
• disturbance of ventricular contractions (fibrillation).

In order to prevent complications leading to death, it is necessary to adhere to certain preventive measures.

Prevention

It is much easier to prevent any disease than to treat it. This is especially true of the heart - vital important body. The first rule for preventing any heart disease is to maintain healthy image life, abandonment bad habits, the presence of moderate physical activity. It is very important for heart health to avoid stressful and conflict situations, nervous strain, mental disorders.

At the first symptoms, consult a doctor for help. Treat all diseases in a timely manner. Close people and relatives of people suffering from cardiovascular pathologies must study the rules of first aid. During heart attack Every minute counts and can cost your life.

Even completely healthy people are recommended to undergo an ECG twice a year. This procedure will help indicate malfunctions of the heart and identify pathologies even in the absence of any symptoms. Slowing of intraventricular conduction is not separate disease. Most often it manifests itself against the background of heart disease. Heart disease does not always make itself felt initial stages. Therefore, each sign must be regarded as a “bell” - a signal from the body about existing problems.

Changes in cardiac activity can occur against the background of non-conduction within the ventricles of the heart. First you need to decide what it is - intraventricular conduction.

Description of the intraventricular conduction system

The intraventricular conduction system is represented by the His bundle, the main, anterior and posterior branches of the left leg, and the right leg. Gradually branching into smaller ones, the branches of the legs pass into the network of Purkipie fibers, which passes through the heart muscle.

Heart contractions occur due to nerve impulses arising in the sinus node and passing through the entire conduction system. A normal impulse causes the left and right ventricles to contract synchronously. The entire process of passing the pulse lasts 0.12 seconds. If any obstacles arise in the system, the path of the impulse and the heart rate are disrupted.

Obstacles in the intraventricular conduction system are called blockages.

Focal intraventricular conduction disturbances are a failure of impulse transmission that occurs distal to the bundle branches. At the same time, conductivity in the Purkiepie network is disrupted and asynchronous contraction of muscle cells in the walls of the ventricles is observed.

Focal blockade occurs in a limited area and it is in this place that conduction is disrupted. Often focal disorders observed together with blockades of the left leg, especially its anterior branch. The combination of blockades creates difficulties in diagnosis and has negative impact on the course of the underlying disease.

Causes of violations

There are functional, organic, medicinal causes the appearance of focal disturbances of intraventricular conduction:

1. Functional reasons - in this case, the activity of the conduction system is disrupted, but its integrity is maintained. The nervous system influences the intraventricular conduction system. Her sympathetic division stimulates cardiac activity, and parasympathetic inhibits it. Normally, both departments work in balance. If the activity of the parasympathetic department predominates due to any reason, a blockade may occur.
2. Organic reasons - change the structure of the intraventricular conduction system. The changes may be reversible. They arise as a consequence of congenital heart defects, cardiomyopathy, coronary heart disease, and after surgery.
3. Medicinal causes - some medical supplies in case of overdose or when prescribed without taking into account contraindications and individual characteristics patient contribute to the appearance of blockade.

Symptoms of impaired conductivity

When cardiac conduction is impaired, the following symptoms most often appear:

• Cardiopalmus;
• Interruptions of heart rhythm;
• Heart stopping;
• Dizziness, fainting;
• Dyspnea;
• Reduced performance, fatigue, weakness;
• Rare pulse.

Diagnosis of disorders

The main method for diagnosing focal disturbances of intraventricular conduction is electrocardiography.

More informative method is Holter monitoring. The essence of diagnosis is that electrocardiography is recorded continuously on a memory card located in a wearable cardiac recorder. After computer processing of the recording, you can get a conclusion about heart rate, its violations, changes.

Another option for diagnosing conduction abnormalities is His bundle electrography. It is necessary because this is an examination that, unlike conventional electrocardiography, can determine the localization of blockades and allows one to analyze the process of the passage of impulses.

Exercise testing provides an opportunity to determine participation nervous system in the occurrence of violations.

Treatment of impaired conductivity

Treatment depends on several factors:

• The reasons for the violation;
• The influence of the nervous system on the occurrence of blockades;
• Level of conduction disturbance.

First, the disease that caused the blockade is determined. The treatment should be aimed at eliminating the cause of the failure. In this case, it is necessary to avoid influences that worsen the passage nerve impulse in heart. Drugs that slow down atrioventricular conduction are prescribed with caution. What it is? This is the period of time during which a nerve impulse from the sinoatrial node reaches the ventricles through the cardiac conduction system.

If the influence of the parasympathetic nervous system is established, then drugs are prescribed to reduce its activity.

No treatment is required if leg blocks occur. But they may be the first symptoms of heart disease - coronary disease, myocarditis, heart failure.

If it is not possible to determine the disease and identify the cause that caused focal disturbances in intraventricular conduction, then outpatient observation, including ECG monitoring. Due to the fact that the distal type of blockade is dangerous, it is necessary to install a permanent pacemaker.

Preventative measures for the appearance inside ventricular blocks is timely treatment diseases that cause them, and adequate use of antiarrhythmic drugs.

Video on the topic

Violation of intraventricular conduction of the heart - what is it? If, during the examination of a patient with complaints of pain in the heart muscle, this disease is detected, clearly visible on an ECG (electrocardiogram), then the patient is progressing to a 2nd or 3rd degree blockade.

Show all

Types of illness

Violation of ventricular conduction is very dangerous. It is divided into 2 main subspecies:

1. 1. The impulse does not pass through one or another area of ​​the heart muscle. This causes a blockage that is life-threatening to the patient.
2. 2. The impulse moves in the desired direction, but passes with some delay. The slowdown causes an incomplete blockage of the heart.

Such complete or partial blocks appear on the so-called bundle branches.

If a local disturbance of intraventricular conduction occurs due to right side His bundle, then the rhythm is disturbed normal contraction right ventricle. If this occurs along the left bundle branch, then the left ventricle suffers accordingly. Along with this there may be Various types lesions due to intraventricular nonconduction of impulses. They are as follows:

1. 1. Weak local lesions.
2. 2. Complete blocking of the left ventricle, characteristic when acute heart attack myocardium.
3. 3. Nonspecific lesions due to blockade of intraventricular impulses.

All of them have their own specifics of diagnosis and treatment, and in some forms of diseases of this type the treatment process is not carried out at all.





Causes of the disease

The causes of the disease can be completely different. The following are considered the main ones:

1. 1. In an absolutely healthy person, it is relatively common to experience local violations intraventricular conduction on the right leg of the so-called bundle of His.
2. 2. If the child’s foramen ovale remains open on the heart muscle, this can lead to local disruption of intraventricular conduction of the heart in children.
3. 3. Complete blocking of any of the bundle branches is possible. This may occur due to the occurrence of diseases of the heart muscle such as myocardial hypertrophy (thickening and growth of the heart) during the development of valve defects, acute infarction of the heart muscle, and coronary heart disease. The same problems can occur during diseases of the bronchi and lungs, for example, with obstructive bronchitis, bronchiectasis, during development bronchial asthma. WITH similar phenomena doctors encounter during the onset of myocarditis, cardiomyopathy, post-infarction cardiosclerosis.
4. 4. In some cases, a nonspecific violation of intraventricular conduction is possible, which occurs due to incorrect, uncoordinated operation of one or more cardiac muscle systems. Typically, this can cause a slowdown in heart contractions in case of incomplete blockade, and in the case of complete failure of the control impulse, a practical stop of the myocardium is possible. Such disorders occur due to the appearance of a prophet of the heart, the formation of scars or cicatrices on it, and splitting in the ventricles themselves. Most often this occurs due to inflammatory processes or organic effects. It may also be a consequence of improper use of certain medications.





Main symptoms

Signs of the development of such a lesion with partial or complete failure of control impulses to pass through the heart muscle are as follows:

1. 1. With partially impaired conduction, most people may feel practically nothing, since this condition in many cases does not manifest itself clinically.
2. 2. If a person has a complete blockage of the passage of impulses on the branches of the His bundle, then signs such as pain in the chest, rare impulses, possible total loss consciousness.
3. 3. When examining a patient who complains of sudden, severe pressing pain behind the sternum, sudden, unfounded weakness, the appearance of cold sweat; the electrocardiogram usually reveals complete blockade of the left ventricle. This makes it possible to determine the development of acute myocardial infarction, which is usually disguised as failure of the impulse. The patient is fixed rare pulse, he often feels ill. It can be quite difficult to determine the first time the presence of a heart attack in a person using an electrocardiogram, therefore, if this lesion is suspected, patients are urgently hospitalized.





Symptoms in nonspecific cases of the disease

With such a violation of the passage of impulses, most often no signs of the disease are detected, since the shifts on the electrocardiogram are so small that they are very difficult to identify. But there are still some signs, if you notice them, you should urgently take the patient to the doctor. Typically, the patient's disease manifests itself as follows:

1. 1. A person complains of fairly frequent dizziness.
2. 2. The patient develops noticeable shortness of breath, which does not disappear even if he is at rest.
3. 3. Often a patient with a nonspecific impulse transmission disorder complains of an incomprehensible cold in the area of ​​the heart muscle.
4. 4. Such a person gets tired in a fairly short period of time, and he does not have enough strength to complete the task.
5. 5. If you measure the pulse of such a patient, it turns out that it has slowed down significantly.
6. 6. A person begins to complain of memory impairment. He cannot remember much, sometimes even what he did recently.
7. 7. During daylight hours, the patient may experience several mood swings.
8. 8. A sick person is overwhelmed by an incomprehensible feeling of fear. He has disturbing thoughts for which there are no prerequisites. Usually the patient complains to his family about the fear of death that haunts him even in his sleep.
9. 9. A nonspecific disturbance in the conduction of impulses in the ventricles of the heart muscle can suddenly manifest itself in the form of a person falling on a completely level place.



If the patient has at least one of these signs, then an urgent need to call a doctor, as hospitalization may be required.

Diagnosis of pathology

If a person has symptoms of these diseases, then an urgent examination by a cardiologist or arrhythmologist is necessary. After a preliminary external examination and recording the patient’s complaints, they will refer the patient to undergo laboratory research for the purpose of making a diagnosis. In this case, they are usually prescribed following types checks and tests:

1. 1. Electrocardiograms are monitored using the Holter technique. It is needed in order to identify the failure of impulses over 24 hours.
2. 2. The patient must undergo special tests with the results recorded on an electrocardiogram. For these purposes, exercise bikes and treadmills are used for testing. The patient can walk on a treadmill or pedal a stationary bicycle, while electrocardiogram electrodes will be attached to it. This makes it possible to establish an accurate connection between impaired conductivity and the load on the patient.
3. 3. At the next stage, the heart muscle is examined using ultrasound equipment, which can reveal pathology in the structure of the heart and assess the performance of the myocardium.



1. 1. Vitamin and mineral complexes.
2. 2. drugs that will significantly improve blood supply to the heart, for example, ATP, Preductal and others.

If a patient is diagnosed with complete blockade of the ventricles due to failure of the impulse to pass through, then a pacemaker may be required, otherwise bradycardia occurs in the heart muscle, which can lead to complications and even death.

For nonspecific disturbances in the transmission of impulses, no drugs usually help. Therefore, doctors prescribe to patients special diet and long rest. This inhibits negative processes, which allows the patient to live longer.

If a nonspecific lesion is not treated, the disease progresses rapidly, and this can cause the following consequences:

1. 1. Sudden death (with complete blockade).
2. 2. Development of heart failure.
3. 3. The appearance of other serious diseases.
4. 4. Impaired blood circulation in the brain. In this case, a stroke develops.
5. 5. Surgery may be required.
6. 6. Blood clots begin to form en masse on the vessels.

If the disease is detected in time, then when a person switches to healthy image life (diet, giving up cigarettes, stopping drinking alcohol, sometimes medications may be needed) it is possible to stop the development of the disease.



With partial disruption of the passage of impulses, the prognosis is most often favorable.

If there is a complete blockage in any area or the entire heart muscle, sudden cardiac arrest may occur with fatal. In some cases, ventricular fibrillation occurs. Therefore, the prognosis is unfavorable.

Intraventricular conduction disorders are asymptomatic for a long time: they are detected during routine examination. Sometimes transmission problems nervous excitement through the ventricles appear suddenly due to various pathologies hearts.

Intraventricular conduction disorders of the heart: what is it? Let's try to find out the causes, features of the course of this pathological condition and treatment options.

Heart: its tasks and structure

The transmission of nerve impulses is the primary function of the heart muscle. Nervous excitation is gradually transmitted from the sinus node to the area of ​​the ventricles and atria.

The supply of impulses from one structure to another occurs thanks to a special plexus of cells located deep in the interventricular septum. It is called the bundles of His. They are divided into legs: right and left. The left leg is front and back.

Interruption of the transmission of nerve impulses is included in the concept of “blockade”. It can be organic or functional.

The essence of blockades

By “intraventricular blockade” we mean selective or absolute cessation of the supply of impulses along the legs of His.

Excitation reaches the contractile structures of one or both ventricles with a delay. Therefore, the processes of repolarization and depolarization of the ventricles occur intermittently. Pathological changes are displayed in the ECG results.

What are the types of intraventricular conduction disorders?

The type of blockade depends on the localization of the pathological process:

• One bundle – there is a delay in nerve transmission in 1 bundle (left anterior, posterior or right leg);
• Two bundles - the transmission of impulses is disrupted in 2 bundles (one-sided - left leg, two-sided - right leg with anterior or posterior left);
• Three beams – pulse delay is observed in 3 beams.

Ventricular block can be:

• Full;
• Incomplete (partial slowdown of excitation conduction).

Problematic intraventricular conduction is also divided into:

• Focal - local pathological changes are not observed on all ECGs;
• Arborization – problems with conductivity in the terminal sections of Purkinje fibers.

Depending on the nature of blockade deviations, there are:

• Persistent;
• Transient (transmission of impulses is sometimes normal, sometimes not);
• Alternating (one type of blockade is observed, then another).

Causes of intraventricular conduction abnormalities

Malfunctions in the functioning or structure of the heart, which often cause internal interventricular block:

• Ischemic heart damage;
• Excessive enlargement of the heart muscle;
• Obstruction from the left ventricle;
• Myocarditis;
• Constant high blood pressure;
• Cardiosclerosis (local and general damage).

Intraventricular conduction disturbances are observed when:

• Drug intoxication;
• Thromboembolism pulmonary artery;
• Thyrotoxicosis;
• Nonspecific electrolyte imbalance;
• Obstructive pathology of chronic pulmonary tissues.

Indicators of intraventricular conduction disturbances on the ECG

The elements by which data are assessed when examining the heart on an ECG depend on the type of blockade.

They will be different:

• Vector of the cardiac muscle axis;
• Shape of the ventricles;
• Localization in chest and conventional leads;
• Duration of intervals;
• The width of the teeth.

Blockade of both bundles is considered as a condition that foreshadows the development of blockade in 3 bundles. Such a blockade on ECG results sometimes manifests itself as a two-bundle blockade (depending on the location of the affected area).

When interpreting the results, the doctor always compares the data from the latest ECG with the data obtained earlier.

A change in the shape of the ventricles does not always indicate a problem with the transmission of nervous excitation. It occurs with excessive development of the right ventricle, as well as with acute cor pulmonale.

Prevalence of intraventricular conduction disorders

Deviations in ventricular conduction occur in adult patients, more often in the elderly. The most common blockade is that affects the left bundle (superior anterior fascicle).

Less often in practice, doctors are faced with problematic conduction of the impulse along the right bundle branch. The posterior bundle experiences difficulty transmitting excitation extremely rarely.

Typical clinical symptoms interventricular excitability is absent in disorders. Changes are visible only on the ECG.

Statistics indicate that intraventricular blocks occur in 2.4% of cases among all heart diseases diagnosed using an ECG.

Some blocks (right leg) do not require special therapy. Other clinical cases(blockade of three bundles at once) need serious treatment, as they lead to death.

Ventricular blocks in children

In a child, problematic intraventricular conduction indicates congenital defects. Sometimes it is a consequence genetic abnormalities. Local delays in the transmission of nerve impulses along the right leg are not a deviation, but normal condition for children.

Heart blockade in young patients results in shortness of breath and general weakness, which progresses to fainting. Symptoms occur against the background nervous overstrain, heavy physical activity.

Fainting is accompanied by blueness skin, lack of pulse, convulsions. Temporary asystole is observed. It can be short-term or long-term. The latter threatens the child's life.

The mechanism of blockade in the right leg and its causes

With absolute right bundle branch block, impulses reach the right ventricle and the adjacent septum through the left ventricle and its septum. The latter are among the first to receive excitation, and then slowly transmit it to the right ventricle.

Partial blockade of the right leg is characterized by natural way pulse transmission, however, the quality of this transmission is significantly reduced due to a decrease in speed.

Absolute blockade occurs when there is excessive load on the right ventricle.

This is observed when:

• Ischemic disease (chronic) in combination with hypertension;
• Congenital malformations of one or another structure of the heart;
• Mitral valve stenosis;
• Chronic disease of the lung tissue;
• Heart attack conditions.

Partial blockade is caused by:

• Sclerotic, inflammatory disorders in the heart, electrolyte abnormalities;
• Use of certain medications based on quinidine, digitalis.

Mechanism of blockade of the left anterior branch

The mechanism is associated with obstructed conduction of excitation along the walls of the left ventricle (anterior, lateral). Initially, it is fixed in the left posterior branch, the ventricular septum, the lower part back wall. Next, the impulse, passing from bottom to top, reaches the left ventricle (its anterior lateral part).

This type of blockage occurs due to diseases of the left heart chamber:

• Myocarditis;
• Aortic defect;
• Local cardiosclerosis.

The mechanism of a two-bundle blockade of the right leg with the left anterior branch

Due to the fact that the problems of a two-fascicle blockade lie in damage to the right leg and the left anterior bundle at once, the features of impulse transmission are as follows:

• Initially, excitation comes to the left ventricle (posterior wall);
• It then reaches the anterior and lateral portions of the left ventricle;
• Finally, the impulse appears in the right ventricle.

Such blockades occur due to:

• Heart defects;
• Heart attack conditions;
• Ventricular lesions of various origins.

Mechanism of blockade of the right leg with the left posterior branch

Through a branch (left anterior) not affected by the pathological process, excitation spreads to the walls of the left ventricle, then to its lower parts. At the very end, the impulse covers the right ventricle.

These abnormalities are provoked by pathologies affecting the walls of the left ventricle.

Mechanism of three-bundle blockades

This blockade is characterized by the spread of the nerve impulse from the atria to the ventricles along a branch that is less affected by the pathological process. Symptoms of atrioventricular block are observed.

The blockade appears due to organic damage in the myocardium.

Symptoms of intraventricular conduction disorders

All types of blockades, except three-bundle, have nonspecific symptoms. However, patients still feel unwell: their health changes for the worse.

With blockade of 3 bundles, 3 degrees of severity are distinguished:

• 1 – excitement passes, but slowly;
• 2 – some of the impulses are delayed, and the rest pass through areas that are only locally changed.
• 3 – passage of excitation through the ventricles is impossible.

The ventricular rhythm becomes less frequent: 20-40 beats/min.

The patient has:

• Exercise intolerance. They are accompanied by weakness throughout the body, shortness of breath, and discomfort in the heart area.
• Fainting states.
• Decreased heart rate.

Complications of three-bundle block include:

• Cardiogenic shock.
• Specific attacks during which the patient faints, and after a couple of minutes comes to his senses. Frequently repeated attacks lead to memory impairment.
• Sudden death due to cessation of cardiac activity.
• Severe renal failure.

Features of treatment

Long-term intraventricular block does not require treatment. Pathological changes in the intraventricular localization, detected for the first time, require establishing the reasons for the appearance with hospitalization of the patient.

If the cause of the pathological condition is myocarditis or pulmonary embolism, this means that treatment should be aimed at eliminating these diseases.

If the cause of intracardiac blockade lies in myocardial ischemia, then doctors prescribe medications that:

• Improve blood supply to the heart muscle;
• Will help cope with the signs of atherosclerosis.

In this clinical situation the following are used:

• Coronarolytics;
• β-blockers.

Myocardial infarction requires the following actions on the part of physicians:

• Prescribing medications that can limit the focal spread of necrosis;
• Carrying out manipulations to reduce the area of ​​ischemia;
• Elimination of associated complications.

In case of inflammatory origin of intraventricular conduction disorders, the following is recommended:

• Antibacterial agents;
• Hormonal drugs.

For chronic heart failure, doctors prescribe in small dosages:

• Diuretics;
• "Digitalis".

It is dangerous to ignore a three-fascicle blockade. It can lead to asystole when sinus rhythm goes to “no”, and electrical activity stops.

Treatment of two-bundle and three-bundle blockades is carried out using the installation of an electrical pacemaker. It comes in two types: temporary and permanent. A patient needs a temporary device when a blockade suddenly develops in several bundles at once.

Find out how the installation is carried out

A permanent pacemaker is installed according to indications:

• When 2 bundles of one leg are affected. He is characterized by decreased heart rate, heart failure, and symptoms of angina pectoris.
• When 2 legs are affected and signs of atrioventricular block are present.
• With blockade of impulses along the right and left legs (posterior section).
• With a blockade of both legs, which is fixed for 3 weeks after a heart attack.
• During fainting attacks.

Probable predictions

Making a prognosis regarding intraventricular blocks is problematic. This pathological condition not independent: it is closely related to the underlying disease.

Only based on the characteristics and severity of the underlying disease, on the results of the treatment, can we talk about the future fate of the patient.

There are some statistics regarding blockades:

• Problems with the conduction of the left bundle increase the likelihood of death by 6 times.
• Worsening of symptoms is observed with double-bundle lesions of the ventricles.
• If at acute development myocardial infarction, the appearance of one or another blockade is noticed, then death occurs in 50% of cases. Blockade in this situation indicates the spread of the area of ​​necrosis.
• The most difficult to predict case is three-bundle block. She has high risk the appearance of asystoles, and thereby increased risk mortality.

A cardiologist deals with the problem of ventricular blocks. When pathological process observed when emergency conditions(myocardial infarction), the patient is treated in an intensive care unit.

In no case should blockades be considered as an independent disease separate from cardiogenic pathologies. Determining the type of blockade is necessary so that the doctor can select correct option treatment.

Self-treatment or use folk remedies may worsen the course of the disease and lead to serious complications, even death.

Video: Atrial flutter. Heart rhythm disturbances.

Blockade of the legs of His (right - PNPG, left - LBP), their branches or Purkinje fibers reduces the speed of intraventricular conduction. This leads to disruption of local contraction muscle fibers or decrease cardiac output. An ECG is required for diagnosis. Treatment is medicinal in the presence of clinical manifestations.

Read in this article

What is intraventricular conduction of the heart?

The cardiac impulse is formed in the cells of the sinus node, passes through the atrioventricular junction and is directed to the ventricles, in which the pathways are represented by the His bundle. It first runs along the septum, then divides into branches, the right one descends to the ventricle of the same name, and the left one is divided into anterior and posterior, simulating contractions of the left ventricle.

Directly to muscle layer The conducting cells of the heart are small Purkinje fibers.

When the speed of pulse propagation decreases, . This is not an independent disease, but occurs when the heart muscle is damaged, pulmonary pathology, or electrolyte imbalance.

Causes of conduction disorders

Factors leading to disruption of intraventricular conduction are most often associated with cardiac pathology, but noncardiac diseases also occur. The structure of the reasons for the development of blockade differs in children, adolescents and adults.

In adults

The most common disease with disturbances in the propagation of impulses in the myocardium is ischemia of the heart muscle (,). The occurrence of His bundle block also occurs in the following conditions:

• overdose of potassium or beta-blockers.

In teenagers

A decrease in the conduction of impulses along the ventricular part of the myocardium is diagnosed when:

• infective endocarditis;
• acquired;
• symptomatic arterial hypertension;
• myocardial dystrophy;

Incomplete blockade of PNPG in a teenager without clinical signs considered as a physiological state.

In children

There are congenital variants of His bundle block; they usually do not affect the functioning of the heart or the well-being of the child. More dangerous are violations with congenital defects:

Symptoms of local and local disturbances on the ECG

Most bundle blockades are detected only on an ECG without any symptoms or against the background of the main manifestations of the disease that caused this deviation. With ineffective blood circulation, weakness, dizziness, and fainting appear. They are associated with low blood release into the arterial network due to asynchronous contraction of muscle fibers.

PNPG blockade

The right ventricle is excited by signals coming from the left side of the heart. This is manifested by an expanded S, high, wide R, the ventricular complex acquires a qRS configuration, it is lengthened to 0.11 seconds.

LBP blockade

With complete damage, there is no movement of signals along the trunk or two branches at once. The spread of excitation to the left ventricle comes from the right through the Purkinje cells. Electric axis deviated to the left, QRS wide and deformed.

The anterior part of the pedicle is responsible for contraction of the anterolateral wall. During blockade, impulses approach from the posterior wall in the direction from the apex of the heart to the base. When the posterior branch is blocked, the excitation waves go in the opposite direction. Characterized by an increase in ventricular complexes on the electrocardiogram.

Double bundle lesions

Conduction disturbances along the PNH and the anterior part of the LPPH can be suspected by an expanded QRS, S notch, negative T waves, displacement of the heart axis in left side. If the right leg and the posterior branch of the left are affected, then the ECG shows signs of PNPG block and axis deviation to the right. This combination is often found with common injuries ( massive heart attack, myocarditis).

Three-bundle conduction disorders

If all three branches are blocked, then the waves pass along the less destroyed one and join. When signals stop completely, the atria function in normal rhythm, and the ventricles contract with their own (idioventricular) periodicity. The ECG shows different duration PQ intervals. Often, a complete three-fascicular block leads to atrial fibrillation or stopping contractions.

If the results of standard ECG recording were not convincing enough, then the transesophageal method or Holter monitoring or rhythmocardiography can be used. To detect the cause of conduction blockades, patients are prescribed cardiac ultrasound, MRI, MSCT, and positron emission tomography.

Watch the video about cardiac conduction disorders:

How to treat intraventricular conduction disorders of the heart

If the patient’s condition is stable and the blockade has been in place for a long time special treatment is not carried out. To improve myocardial conductivity, the underlying disease must be treated.

Depending on the origin of this pathology, treatment may be prescribed. antihypertensive drugs, nitrates. With a rare ventricular rhythm and atrioventricular block, a pacemaker may be required.

In case of acute development of blockade of the legs of His, the following is prescribed for a temporary effect:

• anticholinergics (Atropine, Platiphylline);
• adrenergic stimulants (Norepinephrine, Isadrin);
• corticosteroids for inflammatory process(Dexamethasone, Hydrocortisone);
• diuretics to reduce potassium levels (Lasix);
• temporary cardiac pacing.

Prognosis for patients

Blockade of the LBP when both branches are affected may be a sign of extensive destruction of the heart muscle during a heart attack, therefore its addition is regarded as one of the risk factors for cardiovascular death.

When blocking PNPG and asymptomatic forms of other localization, such arrhythmia proceeds benignly. Deterioration of ECG indicators, the occurrence of atrioventricular block, hypertension, myocardial hypertrophy, and circulatory failure increase the possibility of cardiac decompensation.

A decrease in intraventricular impulse conduction occurs with myocardial pathology, pulmonary hypertension, developmental defects. It manifests itself in the form of His bundle blocks (one-, two- and three-bundle lesions). Symptoms are absent or determined by an underlying disease.

Asymptomatic cases are not subject to therapy, and in case of acute development of blockade, conduction improvement is achieved by administering medications. If the contraction rhythm is rare, a pacemaker is required.

Read also

The detected bundle branch block indicates many abnormalities in the functioning of the myocardium. It can be right and left, complete and incomplete, branches, anterior branches. Why is blockade dangerous in adults and children? What are the ECG signs and treatment?