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Cardiac patients are often diagnosed with blockade right leg bunch of His. This pathology It is characterized by a violation of the passage of a nerve signal through the heart. This human organ has the following important properties:

excitability;
conductivity;
automatism;
the ability to shrink.

The bundle of His is important element conduction system, thanks to which the signal passes through all the tissues of the myocardium.

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Etiology of the disease

The conduction system includes the sinoatrial node (located in the right atrium), the atrioventricular node (localized in the interatrial septum), the His bundle and Purkinje fibers. The bundle of His connects the atria and ventricles of the heart. It consists of a base (trunk) and 2 legs (left and right). Difficulty in conducting an impulse causes a violation of the contractility of the heart.

Most often this violation occurs against the background of other diseases. This disorder is diagnosed in 0.6% of people. With age, the incidence increases. Among people over 55 years of age, the frequency of this dysfunction of the heart is 20 cases per 1000. In old age (after 60 years), the blockade of the legs of His is detected in 1-2% of people.

Distinguish between complete and partial blocking of conduction. In the first case, the signal does not pass through the heart. Not complete blockade characterized by a decrease in the speed of the signal. There are also permanent and transient blockades. In the absence of proper treatment, this pathological condition can lead to serious consequences up to asystole (cardiac arrest and death of a person).

Reasons for the development of the disease

The causes of conduction disturbances are different. There are the following etiological factors:

heart failure;
cardiomyopathy;
congenital heart defects (coarctation of the aorta);
acquired defects (mitral and tricuspid insufficiency, stenosis of the bicuspid and tricuspid valves);
heart surgery;
injuries of the chest cavity;
myocarditis;
autoimmune diseases;
high blood pressure;
uncontrolled medication (diuretic, antiarrhythmic drugs, cardiac glycosides);
violation of the electrolyte state of the blood;
alcohol intoxication;
the impact of drugs;
smoking;
dysfunction of the autonomic nervous system;
atrial septal defect;
infective endocarditis;
acute myocardial infarction;
aortic valve defects;
cor pulmonale;
myocardial dystrophy.

The cause of the blockade of the anterior branch of the left leg of the His bundle (LBVLNPG) may be hormonal disorders. This is possible with pathology of the thyroid gland (hyperthyroidism), adrenal glands or diabetes. Difficulty in conduction is possible against the background of a lack of oxygen. This is observed in pulmonary pathology (asthma, pneumonia, chronic obstructive bronchitis).

In young children, signs of this pathology are often observed against the background of congenital anomalies. The cause may be an open foramen ovale and mitral valve prolapse. Complete blockade of the left leg of the bundle of His is most often due to congenital malformations. Sometimes blockades occur for no reason. They are called idiopathic.

Most common cause conduction disorder is oxygen starvation myocardium (ischemia) and necrosis of a separate part of the heart. This is possible against the background of IHD (angina pectoris, myocardial infarction). Risk factors include smoking, alcoholism, self-treatment heart disease, intoxication of the body, the presence of foci chronic infection, stress, heavy physical work, atherosclerosis of the heart vessels.

The most frequent manifestations

Symptoms are not always pronounced. With the right blockade, when signal transmission along 1 bundle is difficult, symptoms are often absent. Incomplete blockade is almost always detected incidentally during electrocardiography. Similar condition occurs in healthy, trained individuals. In this situation, it is not regarded as a pathology.

Complete blockade is often accompanied by dizziness, weakness, fatigue, shortness of breath, decreased performance, pain in the heart. These disorders are often symptoms of the underlying disease. The blockade of the anterior branch of the left leg of the bundle of His also proceeds with meager symptoms. The blockade is most difficult when 3 bundles are involved in the process at once.

The frequency of contractions in this case is 20-40 beats per minute. This causes a disturbance cerebral blood flow and sometimes sudden cardiac death. Blockade of the right leg is easy to identify in the process of electrocardiography. On the cardiogram, the expansion of the S wave and the increase in the QRS complex in the left leads are determined. In the right assignments pathological complexes are found.

What is the danger of the disease?

The consequences of blockade of the right leg can be serious for a person. Incomplete blockade of the right leg does not pose a great danger. With complete blockade, the impulse is conducted along the left side of the heart on the left side of the septum between the ventricles. Severe consequences possible when several legs and branches are involved in the process at once.

In this case, the following complications are possible:

sudden stop hearts;
ventricular tachycardia;
ventricular fibrillation;
progression of the underlying disease;
acute disorder cerebral circulation(stroke);
thromboembolism.

Such consequences are largely due to the underlying disease.

Diagnostic measures

Treatment of such patients is carried out only with obvious signs blockade. The diagnosis is made on the basis of the results of the following studies:

electrocardiography;
listening to the heart;
blood and urine tests;
daily ECG monitoring;
Ultrasound of the heart.

The blockade of the bundle of His on the ECG has specific signs. Diagnosis is aimed at identifying the underlying heart disease (defects, coronary artery disease). Mandatory laboratory research. Hormone testing can reveal non-cardiac causes of conduction disturbances. Daily monitoring of the work of the heart is mandatory.

Such persons must wear a special device that records the work of the heart. A person should keep a diary. When evaluating the data obtained, it is possible to establish a relationship between heart failures and physical activity, stress, or other factors. Of great importance are the results of a survey of the patient. Ultrasound and MRI can detect organic damage to the heart (enlarged chambers, defects).

Scheme of treatment of patients

There is no medicine that would restore normal cardiac conduction. In the absence of symptoms, treatment is not required. Therapeutic measures focused on the underlying disease. The following drugs may be used:

antihypertensives ( ACE inhibitors or calcium channel blockers)
antianginal agents (nitrates of short and long action);
means that reduce platelet aggregation (Trombo ACC, Cardiomagnyl, Aspirin);
adrenomimetics;
glucocorticoids;
NSAIDs;
antibiotics;
blockers (Bisoprolol).

For overall strengthening vitamins and antioxidants are prescribed to the body. Can be used for sedation herbal remedies(motherwort, St. John's wort). With existing heart failure, cardiac glycosides are prescribed. Diuretics and antibiotics are often included in the treatment regimen for heart disease. All patients should normalize their lifestyle: quit smoking and alcohol, limit the use of sweets, salt and fatty foods, enrich their diet fresh fruit and vegetables, exclude stressful situations.

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Incomplete blockade of the right leg of the bundle of His - is it a "technical" diagnosis or a disease?

Such an unusual name for the diagnosis attracts, most likely, the word "blockade". In itself, this, of course, is alarming, but it does not say anything concrete to a non-specialist. In order to understand the meaning of this complex term, one must remember such an unusual anatomical structure as the conduction system of the heart.

This formation is designed to correctly distribute the impulses that go down from the sinus node. Conducting system human heart responsible for the correct and synchronous contraction of the atria, as well as the ventricles. It is clear that the heart is a pump that "drives blood in one direction."

The general direction of blood is:

from the left ventricle, blood is ejected into the aorta, the largest artery in the body;
then, through a system of branching arteries of a smaller caliber, the blood enters the capillaries, while the speed of its current slows down;
gas exchange occurs in the capillaries, and the process of tissue respiration occurs: oxygen is given to the tissues, and carbon dioxide is taken in;
then, through the venous vessels of an ever-increasing caliber, the blood enters the system of hollow veins, and ends up in the right atrium, which is the main "collector" of venous blood;
from the right atrium, the blood is sent to the right ventricle, and from there to the lungs, to enrich the venous blood with oxygen and turn it into scarlet, arterial blood.

Bundle of His - what is it and why is it needed?

As can be seen, arterial and deoxygenated blood in our heart does not mix, and the chambers of the heart contract strictly synchronously: first, ventricular systole occurs, and the atria at this time “rest”, filling with blood. The ventricles then fill with blood during diastole, which is ejected from the atria.

For normal contraction the heart needs the atria to contract together, like the ventricles, in pairs. And between them there must be strict synchronicity.

In the event that such a synchronous contraction does not occur, it is possible various options the appearance of the pathology of the conduction of an electrical impulse, which are called blockades. These conditions can be life-threatening.

It is known that in the skin of the heart there is a special conducting system, in the form of special bundles. nerve cells. They form knots and bundles that help conduct impulses from the overlying parts of the heart to the underlying ones. There are patterns of impulse conduction, and there is a strict order.

One of these bundles is the His bundle, which is otherwise referred to as the atrioventricular bundle. It passes in the thickness of the interventricular septum, and splits there into two legs - into the left and right. As the name implies, the right leg goes to the right ventricle, and the left one goes to the myocardium of the left ventricle.

These legs end with special Purkinje fibers that branch in the muscle tissue of the corresponding ventricles. The impulse is conducted through the structures of the His bundle at different speeds, which is, on average, 1-3 meters per second, which is quite noticeable with a beam length of 15-18 mm.

In addition to arrhythmias, blockades of impulse conduction to the underlying parts of the heart can often be detected if, for some reason, there is a complete or incomplete blockage of impulse conduction along one of the legs of this bundle. What is this pathology, and how does it manifest itself?

Incomplete blockade of the right leg of the bundle of His - what is it?

It is important to know that in addition to the bundle of His, which is the main pathway for conducting an impulse, in the myocardium there is also a bundle of Kent, Maheim fibers, and two "alternative tracts" - James and Bershenmanshe. All these paths can serve as additional pathways, therefore, with blockades of the bundle of His, the heart still contracts, nothing terrible happens.

Clinically, this is manifested by the presence of intraventricular blockade syndrome, or by slowing down or stopping the conduction of an electrical impulse to the myocardium of the right ventricle. This occurs when the conduction of the right leg is disturbed.

If a we are talking about an incomplete blockade of the right leg, this indicates that the impulse passes, but its conduction is slowed down. In the event that the impulse does not pass at all to the myocardium, then they speak of a complete blockade. In this case, the right ventricle is still excited and contracting, the person lives, and may not experience any discomfort.

It's just that excitation of the right ventricle begins "in a roundabout way." In other words, the wave of depolarization comes through the left ventricle, and left half(lying on the other side) of the interventricular septum.

Causes of the blockade

It is known that various signs of incomplete blockade of the right leg of the bundle of His, determined by ECG, are found in absolutely healthy people, more often men who do not show any complaints. The frequency of occurrence of this pathology in the population is quite high - 1-2% of the total population.

If we talk about the complete blockade of the right leg, then it occurs in conscripts on average, in 0.2% of all cases, and over the age of 40, this figure rises to 5%. This means that every 20th adult male has some kind of conduction disorder.

As for diseases, a complete blockade is caused by diseases in which overload of the right heart can occur. These include:

Chronic cor pulmonale (this is a condition in which blood circulation in the lungs is difficult, and the preload on the right side of the heart increases). This condition develops in lung diseases: pneumosclerosis, and in many other diseases;
Coronary artery disease (IHD) of the heart, or, especially when combined with arterial hypertension, or (hypertension);
In acute and often with posterior diaphragmatic or apical localization of the necrosis zone;
Sometimes a complete blockade occurs in completely healthy people, but this is rare. Much more often in healthy people, an incomplete conduction disorder is detected.

If we talk about incomplete blockade, then exactly the same reasons lead to it, and diseases that only occur in a “softer” form. In old age, these are all sorts of myocarditis, cardiosclerosis, chronic ischemia myocardium.

One of the important causes of incomplete conduction disturbance is the development of myocardial hypertrophy. In this case, the delay in the conduction of the impulse occurs because there is simply “a lot” of myocardium, and therefore it seems that the impulse passes slowly.

This situation can develop in people with sports heart, as well as in persons with pulmonary hypertension, because it is in them that the myocardium of the right ventricle should be stronger.

In some cases, incomplete blocking of impulses of the right leg develops with an overdose of cardiac glycosides and beta-blockers, with the treatment of certain antiarrhythmic drugs, for example, quinidine, as well as with severe dehydration (with intestinal infections).

How dangerous is an incomplete blockade of the right leg of the bundle of His? The prognosis for this condition is not at all determined by this formulation of the diagnosis. As stated above, crucial has a degree of development of the underlying disease, as well as the risk of developing a complete atrioventricular block (in which the atria and ventricles can contract each in its own rhythm, disorganized).

It is the latter fact that can lead to the development of ventricular arrhythmias.

It should be noted that the blockade, especially incomplete, does not mean the automatic presence of arrhythmia. Simply, in the presence of predisposing and adverse factors, this can happen, and then the blockade of the leg, albeit incomplete, can increase the risk of sudden cardiac death.

Thus, the probability of the appearance of a complete atrioventricular block in persons with partial conduction disorders of the legs of the bundle of His is 1% per year.

Of course, this figure takes into account conditions in which there is a pronounced cardiac pathology. It is in the presence of AV blockade that treatment will already be required, which may consist in the installation of a pacemaker.

How does the blockade manifest itself?

Incomplete blockade of the right leg of the bundle of His may not affect the heart in any way. All clinical guidelines say that if the blockade has not reached the state of trifascicularity, then it does not manifest itself in any way. That is, in order for any manifestations of the blockade itself to arise (provided that there is no organic disease), then it is necessary that immediately, jointly arise:

blockade of the left leg of the bundle of His;
complete or incomplete atrioventricular block.

In the vast majority of cases, options for incomplete conduction disturbance of only one leg (it doesn’t matter, right or left) is a phenomenon that can only be determined on an ECG, for example, during examination during a physical examination.

In the same case, if the patient's MC has some kind of heart disease, then the whole clinic is due to the main complaints, for example, with emphysema or postinfarction cardiosclerosis, and the blockade of the bundle branch block is a "small and secondary" diagnosis, which practically does not play its own roles.

The only option in which you can suspect the presence of a blockade before electrocardiography is the usual auscultation of the heart, or listening to it with a phonendoscope. The doctor may suspect this by ear if there is a splitting of tones that is not felt by the patient.

The next stage is the usual, routine, during which a special form of ventricular complexes is determined in the first chest leads, as well as a slight increase in the duration of the gastric QRS complex to 0.11 seconds. It is clear that this increase in time arises due to the "circular path", and the indirect following of the impulse along the blocked leg of the His bundle.

Holter monitoring is also shown, in which functional or transient options for the development of the blockade can be identified. This can happen, for example, due to an overdose of some medicines during the treatment of diseases.

In the event that the blockade of the leg occurred against the background cardiac disease, then an intracardiac electrophysiological study is performed. Its main task is to determine whether there are indications for the placement (implantation) of a permanent pacemaker.

Can I go in for sports and serve in the army?

With incomplete blockade of the right leg of the bundle of His, sport is not contraindicated. Indeed, cardiologists are concerned about those conditions that increase the risk of sudden cardiac death, as well as various undiagnosed valvular defects, especially aortic stenosis, which, when the load on the heart increases, can lead to unpredictable complications.

Isolated and asymptomatic conduction disorders, especially in young age do not lead to a significant increase in complications. AT last resort, you can perform Holter monitoring, which will be carried out against the background of sports training.

If the analysis of the results does not reveal progression of the volume of the blockade, the appearance of arrhythmia, or signs of an atrioventricular junction disorder, then contraindications to sporting events does not occur. All that remains is to undergo an ECG annually in order to timely know the state of affairs with intraventricular conduction.

As regards military service, then, as we remember, in the absence of an unambiguous interpretation, the entire emphasis is on “functional dysfunction”. In this case, given the absence of pronounced organic damage and the asymptomatic course, such a young man will be drafted into the army in category B-4, that is, "fit with minor restrictions."

This actually means that he is unfit for the elite units of the RF Armed Forces, that is, where it is more or less prestigious to serve. As a result, he will be sent somewhere to the infantry, or to the signal troops, where, of course, no restrictions will be observed, since the “automatic” definition of the type of troops is already and will serve as a guarantee that such restrictions have already been made.

About the treatment of blockade of the right leg of the bundle of His

As you probably guessed, you need to treat only those options for the blockade, in which there is increased risk development of cardiac death, or there is a pronounced desynchronization in the work of the upper (atria) and lower (ventricles) parts of the heart. As a rule, in this case, we are talking about patients who have clinically significant and reliable signs heart failure.

Such patients are usually admitted to the Department of Interventional Cardiac Surgery and Arrhythmology, or to diagnostic department cardiology hospital. Hospitalization is needed in order to:

choose a good drug therapy if there is a diagnosed arrhythmia against the background of the blockade;
exclude acute myocardial infarction in the event of an acute blockade of the bundle of His bundle (this is always suspicious, but, however, then the left leg is affected, and not the right one);
conduct an electrophysiological intracardiac study;
implant a pacemaker, or perform cardiac synchronization.

To reassure young people and their parents, it is safe to say that a pacemaker is not “just like that” installed. For this, there must be very strict indications, for example:

Alternating blockade of the legs (when there is a "walking" violation of either the left or the right leg;
Atrioventricular blockade of the 3rd degree with the presence of syncope.
Blockade of the legs that occurred in acute myocardial infarction;
Severe heart failure of the 3rd or 4th functional class, despite the correct treatment.

Thus, it becomes clear that it is not the blockade of the right leg of the His bundle that is “treated” at all, but those conditions and diseases that it can aggravate or provoke.

In conclusion, it must be said that in order to avoid confusion and ambiguous interpretation, if there are signs of blockade during the ECG, it is advisable for the patient to undergo an ultrasound of the heart. Only then will it be possible to assess the thickness of the interventricular septum, and to draw a conclusion about the presence or absence of the right ventricle.

Only in this case the diagnosis of blockade of any of the legs will have a valid diagnostic value, since it will be set taking into account the presence or absence of myocardial hypertrophy.

A patient with characteristic symptoms goes to the ECG and sees the following entry in the results: "Complete blockade of the right leg of the His bundle." A lot of questions immediately arise: how dangerous is it, what does it lead to. What is it in general: a disease or a symptom? You shouldn't worry too much, the first thing you need to do is figure it out.

The heart is a complex system

The legs of the bundle of His are a component of the conduction system of the myocardium. They are responsible for bringing the impulses of excitation to the ventricles. The following legs of the bundle of His are distinguished:

left;
right front;
back - it is thicker than others.

Left and right are branches of the back. The legs are interconnected by a mesh of anastomoses. The entire bundle has atypical muscle fibers in its structure. The extreme parts of the legs branch out and create another element of the heart - the Purkinje fibers.

The key task of the bundle is to transmit an electrical impulse to the ventricles from the right atrium. There may be an incomplete or complete violation of the conduction of the impulse, both on the right and on the left leg, and on both at the same time.

Note! RBBB often does not manifest itself clinically, which means that treatment is not carried out.

The risk of RBBB increases with age. If in young people this phenomenon occurs in 0.6%, then for age group older than 55 years, the average is 2%. Blockade of the right leg of the bundle of His is more common in men.

Why is it developing?

The blockade of PNPG is caused by various pathological conditions:

heart defects, including congenital and acquired;
cardiomyopathy, myocardial dystrophy;
ischemia of the heart;
myocarditis of viral and bacterial origin;
myocardial infarction, cardiosclerosis;
rheumatic affections of the heart;
thromboembolism;
chronic lung pathologies that provoke a condition such as cor pulmonale;
underdevelopment of PNPG.

There are other reasons that do not relate to pathological conditions of the myocardium, among them:

chronic pathologies of the respiratory organs, which are accompanied by obstructive processes;
muscular dystrophy;
overdose of cardiac glycosides, diuretics and some other medicines;
smoking for a long period;
alcoholism;
ANS dysfunction;
diseases of the endocrine system;
diabetes;
anemia.

Bundle of His placement

In children, blockade occurs due to small anomalies of the heart, unclosed oval window mitral valve prolapse. If there is no organic lesions heart, this condition is considered normal.

Read also: , arguments of experts

Classification

BNPG are classified according to different features. If we consider it from the position of the conduction of impulses, then it is incomplete when the impulse slows down, but still passes. Complete blockade is called the absolute cessation of impulse transmission.

Separation by the number of non-conductive beams:

Single-beam - the right leg suffers more often, but conduction may disappear only in the left or only in the back.
Two-beam - covers the branch of the left; one branch of the left and right leg.
Three-beam - there is an incomplete or complete blockade of the right and left legs.

Classification by type of development:

Intermittent - during the cardiogram, it appears and disappears.
Constant - can be traced during the study constantly.
Transient - blockade of the right leg of the His bundle on the ECG appears from time to time.
Alternating. This form is characterized by manifestations of the blockade on the right, then on the left leg.

signs

In order to start treatment in a timely manner and not suffer from the consequences, it is important to notice the pathological condition in time. Often RBBB passes without symptoms, especially do not "like" themselves to show single-beam blockade. These are often detected by chance during a planned ECG. If complete blockade of RBBB occurs, symptoms occur, although they are generally not accompanied by serious myocardial damage. Among the signs:

Atypical heart sounds on auscultation.
Vertigo.
Pre-fainting and fainting states.
Feeling short of breath, shortness of breath.
Poor tolerance to any load, fatigue.
A rare manifestation is pain in the heart, a feeling of interruptions in the functioning of the organ.

If the blockade was provoked by the disease, then the manifestations characteristic of it are noted.

ECG blockade back and right legs

Diagnostic methods

If these symptoms appear, it is recommended to go to the doctor for a consultation. Most likely, he will immediately send for an ECG. If the results of the cardiogram showed an incomplete blockade of the right leg, and at the same time the patient does not have any other cardiac pathologies, the condition is considered normal. Additional methods are not assigned.

If a two-beam blockade is found, a detailed examination is needed. When diagnosing a blockade of the two left branches, which is detected for the first time, immediate hospitalization is required. In a similar way, the pathology of the myocardium of an extensive type reveals itself. Often, two-beam blockade masks the manifestation of myocardial infarction. If a left blockade held for a long time, hospital treatment no need.

Three-beam blockade is an indication for immediate hospitalization and a detailed examination.

In addition to the ECG, other methods for tracking are used:

Holter mount. Helps to identify transient blockade.
Transesophageal ECG. Due to the fact that the electrode approaches as close as possible to the heart, it is possible to determine the blockade if it was not shown by the cardiogram.
EchoCG - ultrasound of the heart.
MSCT () is the determining measure if other methods have given controversial results.

Treatment

With RBBB specific treatment medicines are not needed, but only if there is no underlying heart or other disease. The following groups of drugs are often prescribed:

Vitamins. These include thiamine, riboflavin, a nicotinic acid.
Antioxidants.
Herbal sedatives.
Lipid-containing products that help normalize the amount of cholesterol in the blood.
In the case of chronic insufficiency - diuretics and glycosides.
In the presence of hypertension - antihypertensive drugs.
With ischemia - ananginal drugs.
With inflammation of the membranes of the heart - antibiotics, NSAIDs.

Sometimes drug treatment is ineffective to avoid negative consequences. surgical intervention. The operation consists in the installation of a pacemaker. Complete blocks often develop in acute phase myocardial infarction, so temporary electrical stimulation is required.

Treatment for RBBB is often necessary

Consequences and complications

by the most dangerous consequence this conduction disorder becomes sudden death. This is possible with a complete blockade. As for the less critical consequences, this is the development of heart failure. May occur:

Acute disorders of cerebral circulation, which leads to a stroke.
The aggravation of the underlying pathology, which provoked the blockade.
Thromboembolism against the background of blood clotting. Blood clots form not only in the heart, but also in other organs and limbs.

Conclusion

The blockade of the right leg of the bundle of His is not considered dangerous if it is not accompanied by other cardiac pathologies. If there are any, it is required to keep the condition under control and regularly undergo an ECG.

ECG with blockade of the left leg of the bundle of His, causes of the development of pathology, methods of treatment

Blockade of the legs of the bundle of His (right and left): incomplete and complete, what does the ECG say, the reasons, is it dangerous or not?

Almost every one of us, having received a record of an electrocardiogram, will try to decipher it on our own and will certainly look at the conclusion written by the cardiologist. It’s good if no suspicious terms are found there, but even in the midst of complete well-being and in the absence of at least some “heart” symptoms, a record of the blockade cannot but alert.

It is clear that such a phenomenon will cause concern, because something is blocked in the very heart - the main organ that provides nutrition to our entire body. However, not every blockade is considered a disorder, there are also types of it that not only do not interfere normal life, but are well within the norm. Incomplete (partial) blockade of the right leg of the His bundle, (RBBB) is just the case when panic is unnecessary, however, other types of similar intracardiac blocks should not be ignored.

Getting acquainted with the conclusion of cardiography, the patient may find there a record of the blockade of any of the legs of the bundle of His (BPH). This disorder is asymptomatic, diagnosed when recording a cardiogram, but a detailed examination in most of its owners reveals deviations not only of a functional, but also of an organic nature.

The attitude towards blockades of the legs of the bundle of His is ambiguous: some of their varieties are considered a variant of the norm, others are always serious problem, fraught with serious complications, and therefore the attention of cardiologists to this kind of violations is close, and the patient is subjected to a comprehensive examination.

cardiac cycle; the bundle of His bundle provides impulse conduction through the ventricles of the heart

The conduction system of the heart is a kind of modified muscle cells, which acquired during development the ability to transmit electrical signals to cardiomyocytes. Thanks to the coordinated and consistent work of the components of these pathways, the heart contracts rhythmically.

The bundle of His provides excitatory nerve signals to the ventricular myocardium. It originates from the atrioventricular junction, then goes at the top of the interventricular septum, branches below into the right and left legs (LPG). The left leg (LNPG) gives the anterior and posterior branches to the left ventricular myocardium. Right (PNPG), respectively, provides conduction in the myocardium of the right ventricle. The final link of the pathways is the small Purkinje fibers, which carry signals to the main pump of our body and are scattered in the thickness of the muscles to its most remote areas.

Current obstruction nerve impulse can appear in any part of the ventricular myocardium, provoking a block in one leg, one of the branches of the left leg of the bundle of His, two legs at the same time. The volume of the block determines the symptoms - from its absence to total conduction disorder and severe arrhythmia.

Causes and types of ventricular blocks

Scale of defeat neural pathways defines type of blockade

Single-beam - it is difficult to transmit a signal along the right leg of the bundle of His, one of the branches of the left;
Two-beam - blocked branches of the left leg or right leg with one of the branches of the left;
Three-beam - all three paths are involved at once.

Blockade of a section of bundle fibers is complete and incomplete. With partial, only one of the branches suffers, but the work of the rest is preserved. The myocardium receives signals from another source in a roundabout way, but they are somewhat delayed.

Depending on the course, the blockade happens constant,transient and intermittent. Intermittent blockade appears and disappears, which can be traced during the recording of one cardiogram. A transient conduction disorder is seen on a fragment of an electrocardiogram. Sometimes during the recording of the cardiogram, a change in the block of different branches and legs is traced - an alternating blockade.

Defined 3 degrees of NPG block:

At the first degree, the signals reach the cardiomyocytes with a delay.
In the second case, part of the signals does not reach the muscle tissue.
With a total blockade III degree nerve signals do not go to the ventricular myocardium, so it contracts by itself at a very low rate.

Blockade of the conducting ventricular tract is not independent disease. This is a manifestation of another pathology. Quite often, in quite healthy people, an incomplete blockade of RBBB is detected, which is considered normal.

The reasons for the appearance of a conduction block in the heart are very diverse. Among them are directly heart problems, the use of certain drugs, electrolyte imbalance, autonomic and hormonal disorders.

Cardiac causes that provoke a block of fibers of the bundle of His are:

- acute in the form of necrosis () or chronic with cicatricial growths in the myocardium ();
- anomalies in the septa of a congenital nature, narrowing, insufficiency of valve openings, coarctation of the aorta;
Postponed cardiac surgery;
Thickening of the left ventricle with.

As non-cardiac factors that cause block, indicate:

Medicinal effects - use for a long time and without the supervision of a specialist, which can be abused by patients with a cardiological profile;
shifts;
Smoking, alcoholism;
Endocrine pathology;
Prolonged hypoxia and dilation right half hearts with bronchopulmonary diseases (asthma, bronchitis).

If the underlying cause of the block of branches of the bundle of His is not clarified by a comprehensive examination, they speak of an idiopathic disorder.

As mentioned, incomplete blockade of the right bundle branch block is often the norm, if no other changes in the organ are found. Often it is found in childhood and adolescence and can occur in combination with small anomalies - an open interatrial window.

Video: opinion of a cardiologist on incomplete blockades of the right leg of the bundle of His in children

Unlike disorders associated with a change in conduction along the right pedicle, blockades of the branches of the left peduncle are ALWAYS caused by structural heart lesions, therefore not considered as a natural state.

One of the main mechanisms for the formation of a pathological blockade is a mechanical obstacle to the propagation of a nerve signal, in particular, the growth connective tissue with hypoxia, hypertrophy of the heart chambers. Dilatation of organ cavities in chronic insufficiency can be considered another important link in pathogenesis.

So, despite the possible harmlessness (with local detection of incomplete RBBB), damage to the right leg can also accompany a pathology that occurs with excessive load and dilation right side of the body(cor pulmonale, ischemia, tricuspid valve insufficiency).

Blockade of the left leg of the bundle of His is found in cardiosclerosis due to atherosclerotic blockage of the heart arteries, aortic valve disease, necrosis and inflammation of the myocardium, contributing to change in the left side of the heart.

Symptoms of blockade of the legs of the bundle of His

If the distribution of nerve signals over the components of the His bundle is difficult, there may be no symptoms, and if they are, then, as a rule, they are caused by the disease that served as the root cause of the formation of the block, and are extremely non-specific. In other words, it is impossible to guess from the symptoms about the type of conduction disturbance, and in some cases it is extremely difficult to even suspect the presence of a blockade.

Incomplete (partial) blockade, the difficulty in the propagation of signals along one of the branches, provided that the others are functioning, do not cause subjective symptoms. This is an ECG finding prompting further investigations. Some patients experience shortness of breath, pain in the heart, interruptions in its rhythm, fatigue, which, however, do not have a direct connection with the intraventricular block, but characterize a specific disease.

Symptoms of a complete blockade are:

Feeling of irregularity in the work of the heart, palpitations;
Dizziness, fainting;
Soreness in the chest.

With LNPH block, patients feel dizziness, pain in the heart, palpitations. This leg is completely blocked in severe violations - acute macrofocal infarction, cardiomyopathy.

The blockade of three branches at the same time is complete and incomplete. With partial blockade of conduction, some of the signals still reach cardiomyocytes along intact fibers, but with a delay, with complete blockade, the ventricular myocardium contracts due to ectopic foci located outside the conduction pathways, and the ventricles lag far behind the atria.

low frequency ventricular contractions does not allow the organ to provide normal hemodynamics, and among the symptoms, dizziness and episodes of loss of consciousness due to inadequate cerebral circulation come first. Against the background of heart failure, sudden cardiac arrest can occur, leading to the death of the patient.

The blockade of the legs of the bundle of His is dangerous due to organ failure, recurrent attacks with a risk and a possible predisposition to heart attack due to a decrease in blood delivery through coronary arteries, even without atherosclerosis developed in them.

The consequences of intraventricular block can be paroxysmal tachycardia, ventricular fibrillation, cardiac arrest. With a long block suffers systemic circulation with increasing congestion in the organs. Dangerous complications are thromboembolism, for the prevention of which special treatment is indicated.

ECG with blockade of the legs of the bundle of His

The most informative way to detect intraventricular blockades is electrocardiography, which shows changes characteristic of the pathology. Separate forms Conduction disorders are diagnosed with Holter monitoring. Diagnosing NPH blockades is not an easy task, so it is better to entrust it to a specialist, but we will try to figure out a little what and why deviations occur on a regular ECG.

Normally, the distribution of the electrical wave goes evenly from the atrial myocardium to the ventricular one and from left to right, without encountering obstacles anywhere. The passage of nerve signals from the septum to the most distant parts of the heart muscle in healthy people lasts less than 120 ms. With a block, its transmission is inhibited, which means that the depolarization of the ventricular myocardium will also be slowed down. As a result, the muscle needs more time to depolarize and contract, which means that the ventricular QRS complex will begin to lengthen.

Expansion of the ventricular complex to 0.12 seconds or more indicates that the nerve signals do not come through the main NGV, but in a bypass way, respectively, the ventricles contract with a delay.

When the cardiogram shows the correct sinus rhythm along with the phenomena of beam blockades, the P wave is preserved in front of all QRS, indicating that the source of contractility is the sinus node, from where the atria are excited. With ectopia of the source of contractility in the ventricular myocardium, these teeth will not be.

Video: ECG lesson for NPG blockades

Blockade of the right leg of the bundle of His on the ECG

Blockade of the right bundle branch block (RBBB) is perhaps the most common finding in cardiography in athletes; it occurs in many healthy people, in people who do not suffer from cardiac pathology. However, it is usually incomplete and asymptomatic. With excessive load and dilatation of the right chambers of the organ in conditions of cardiac or pulmonary pathology, the block acquires abnormal features.

When it is difficult to transmit signals through RBBB, the right ventricular myocardium and part of the septum receive signals from the RBBB, but excitation comes here later. With incomplete RBBB, the signals along the leg go, but longer than normal, so the ventricular complexes are unusual appearance, but have a normal width.

RBBB on ECG

With complete blockade of the right bundle branch block, the septum depolarizes in the correct direction, from left to right. The cardiogram shows an R wave in V1 and a Q wave in the sixth (left ventricular) wave. After the septum has received its impulse, the excitation of cardiomyocytes is distributed over the left ventricular myocardium, the S wave is recorded on the ECG in the first thoracic and R in the sixth leads.

When the left ventricle is already engulfed in contraction and enters systole, the signal does reach the right ventricle, which depolarizes later, and an additional R in the I chest lead and a deep S in V6 can be traced on the ECG. This is how a specific form of the ventricular complex, RSR1, is formed.

The manifestations of RBBB are:

QRS expansion up to 120 ms or more;
change in the outlines of the QRS: in V1-2, the serration of RSR1 is visible;
the axis of the heart deviates to the right;
high-amplitude and extended R in chest I, wide S in I and left ventricular leads.

Blockade of the left leg of the bundle of His on the ECG

Complete or partial blockade of LDL is almost always a problem associated with structural restructuring of muscle tissue. With this disorder, there is no signal transmission along the LDL, due to which the septum depolarizes in the opposite direction - from right to left. The ECG shows a Q wave in the I chest lead and a small R in V6.

LBBB on ECG

The right ventricular myocardium is depolarized first, then the excitation moves to the entire left ventricular section - R appears in the I chest lead and S in V5-6 in the form of a notch. As the left chamber contracts, an S appears in the first chest lead, and an additional R appears in the sixth.

The most revealing picture of LBBB is observed in the sixth chest lead, which is responsible for the work of the left half of the organ. Here one can observe a prolonged and deformed QRS with a serrated apex, similar to the letter M or W.

About the complete blockade of the left leg of the bundle of His they will say:

wide, deformed, W-shaped ventricular complexes with a width of 120 msec in the I standard and left chest leads;
extended and deep S in the III and first chest leads;
lack of Q in the left chest leads;
the ST segment and the T wave are opposite to the direction of the main ventricular wave;
the electric axis is shifted to the left.

Incomplete blockade of the left leg of the bundle of His appears when the signal does not pass through one of the branches of the leg. On the ECG there will be changes similar to a complete block, but the QRS is not lengthened.

The block of the anterior branch of the LBPH can occur in certain localizations of infarction, sclerosis and pathology with a strong thickening of the left ventricular myocardium - hypertension, some defects, dystrophy and inflammation.

For anterior branch blockLNPG significant left-sided direction of the axis of the heart is indicative, the lengthening of the ventricular complex is subtle or not traced. The S wave is high-amplitude in the left chest leads, becoming serrated.

Blockade of the posterior branch of the LBB gives a right-sided location of the axis, some expansion of the QRS, deepening of S in the left leads. It appears with infarcts of the posterior wall and the diaphragmatic part of the left ventricle, cardiomyopathies and inflammation.

Difficulties in identifying blocks of the intraventricular pathways are often caused by their combination with another cardiac pathology, which gives significant ECG signs - heart attack, hypertrophy, etc., but it is important to remember one feature: with blockade of the legs, there is no Q wave in those leads that characterize the blocked leg . If this prong appears in them, then there is every reason to suspect necrosis of the heart muscle against the background of a conduction block.

Two- and three-beam blockade of the legs of the bundle of His on the ECG

In some cases, there is a block of two pathways at once. The combination of RBBB and left anterior ramus causes QRS prolongation to 0.12 seconds, S-wave notching, T-wave inversion, and left heart axis deviation.

In the case when RBBB is combined with a lesion of the posterior branch of the LBBB, the axis of the heart is directed to the right, and the signs described above for each type of block can be traced on the ECG. Such a conduction disorder speaks of deep and severe changes in the heart muscle.

With a partial violation of conduction in three branches of the intraventricular pathways at once, an atrioventricular blockade of the I or II degree is diagnosed on the ECG. In the first degree, conduction deteriorates, but all impulses reach the ventricular muscle, and in the second, some of the impulses and, accordingly, ventricular contractions drop out.

If the three-beam block is complete, then the impulse from the atria does not pass to the ventricular myocardium, a complete third-degree AV block develops, in which the atria and ventricles contract uncoordinated, in a different rhythm. The ventricular rhythm is irregular and rare, decreasing to 40 per minute.

Diagnosis and treatment of intraventricular blockades

The doctor receives the bulk of information about the degree of conduction disturbance in the bundle of His and its branches from the ECG described above, because it is impossible to listen to or establish it by symptoms. To clarify the diagnosis, a transesophageal ECG recording may be performed.

If the blockade has developed against the background of organic changes in the heart, then the patient is shown an ultrasound examination, if necessary, MRI and scintigraphy can be performed.

Treatment of intraventricular blockade is nonspecific and is directed at the main disease that caused conduction disorders. If the blockade is partial and does not cause any symptoms, then observation with periodic ECG monitoring is sufficient.

Antibiotics and anti-inflammatory in case of myocarditis.

With severe violations of intraventricular conduction with frequent attacks loss of consciousness and cerebral ischemia surgery, consisting in setting . Temporary pacing is carried out in the first two weeks of myocardial infarction when combined with total left-sided blockade.

With a diagnosed blockade of the intraventricular system, it is worth considering the management healthy lifestyle life, even if it is incomplete RBBB with asymptomatic course. Dosed physical activity is an indispensable condition for asymptomatic blockade.

In the case of an existing cardiac pathology that caused a two- or three-beam blockade, the patient should exclude stressful situations, psycho-emotional and physical overload, bad habits. It is important to rest more, normalize nutrition and regimen.

The issue of compatibility of blockades of the legs of the bundle of His and sports worries many parents and adult athletes. It happens that impaired conductivity is detected by chance, with the complete well-being of the subject. The issue of sports in such cases should be decided by a cardiologist.

Incomplete RBBB is detected in almost a third of athletes and, in the absence of changes in the heart itself, cannot be a reason to stop playing sports. However dynamic surveillance still won't hurt.

According to the recommendations of experts, asymptomatic NPH blockades, without impaired function of the atrioventricular node and not provoking arrhythmias, should not be an obstacle to sports. In the case of arrhythmia, structural changes in valves and myocardium diagnosed by echocardiography, physical activity should be limited. At severe disorders rhythm sport is excluded completely.

The prognosis for intraventricular blockade depends on the degree of blockage. In the case of an asymptomatic course, it can be considered favorable, and with the development of arrhythmia against the background of an already existing organic cardiac pathology, it is always serious. Heavy blockades can be deadly, creating risk of sudden death.

Conduction disturbance may contribute to hemodynamic disturbances due to reduced contractile activity myocardium and stroke volume, as a result, blood delivery to the heart itself and other internal organs. All patients with bundle branch blockade should be examined as fully as possible, if necessary, consulted with an arrhythmologist, after which all the recommendations of the attending physician should be followed to prevent dangerous complications.

Video: a lesson on the blockade of the legs of the bundle of His on the ECG

Various pathologies of the heart muscle often put the patient in lung condition bewilderment, because the doctor does not explain the etiology and consequences of a particular condition. Incomplete blockade of the right bundle branch of His is a fairly common conclusion in an ECG. Especially in children who have no symptoms and signs of pathology. What causes can lead to this pathology and in which case treatment is required - you can find out from this article. What is an incomplete blockade of the right leg of the His bundle in the understanding of cardiology - associated with a violation autonomic function central nervous system pathology, under certain circumstances, does not pose a threat to the health and life of the patient. But how this could be dangerous in the future development of the blockade is a separate question. To understand the essence of the issue, one should delve into the anatomy of the heart and its innervation system.

What is the bundle of His and its legs

What is the system of innervation and what role does it play in ensuring the smooth operation of organs and systems, there is no need to tell, everything is clear and without long explanations. If the nerve impulse does not pass, then the inevitable failure of the function occurs. In medicine, the His bundle is a small area of the myocardium in which there are not typical shapes myocytes. It is subdivided into a trunk and two legs: right and left, responsible for the innervation of the anterior and posterior divisions heart muscle. The trunk of the bundle of His is located in the upper parts of the heart, between the two ventricles, and its legs descend to the atria in the form of Purkinje fibers. They are responsible for the innervation of muscle tissue, stimulate contractility myocytes. By and large, this is the coordinator of the synchronous work of the atria and ventricles. At the moment of atrial contraction, the impulse is transmitted to the ventricles.

Incomplete blockade of the right leg of the bundle of His is more common in children and people who have stepped over the age limit of 50 years. Runs without symptoms or signs. Treatment is required only if serious damage conductive fiber and the occurrence of persistent forms of arrhythmia of the heart rhythm.

Types and causes of blockade of the legs of the bundle of His

Types of pathology are divided according to the localization of pathological changes. It can be single-beam, two-beam or three-beam blockade. The patient's condition with a single-beam blockade of the right or left bundle branch of His remains normal. With the defeat of the 2nd and 3rd beams, various clinical symptoms may appear. According to the nature of functional disorders, the following types are distinguished:

complete and incomplete blockade of the nerve impulse;
permanent progressive or remission;
intermittent disturbance with periods of improvement and deterioration of the state of the system nerve conduction;
the transitional form is characterized by the fact that the manifestation of the pathology is not recorded at every ECG reading;
alternating blockade of the legs of the bundle of His differs in that pathological changes can appear alternately on the left and right legs.

The reasons for the incomplete blockade of the right and left legs of the His bundle may be hidden behind a number of pathological disorders, including those affecting the central nervous system. The most common risk factors are:

coronary heart disease in patients over the age of 40;
alcoholic and toxic cardiomyopathy;
diseases of the metabolic system and a decrease in the blood level of certain trace elements (potassium, magnesium);
the presence of scar tissue at the location of the bundle of His (after myocardial infarction, rheumatism, systemic lupus erythematosus, myocarditis);
acquired and birth defects hearts in the form of stenoses and prolapses, coartation and defects;
hypertrophy of cardiac muscle tissue against the background hypertension without compensating it with pharmacological preparations;
thromboembolism of the coronary and pulmonary blood vessels;
bronchial asthma with concomitant respiratory failure;
chronic bronchitis and emphysema;
pulmonary heart.

In children with the appearance on the ECG of signs of incomplete blockade of the legs of the bundle of His, an extended examination is required to exclude intrauterine malformations. This may be an abnormal chord in the cavity of the left ventricle, valve prolapse, or an oval atrial septal defect of the open type.

In the absence of the above organic pathologies, incomplete blockade of the right leg of the His bundle refers to the variants of the norm and is associated exclusively with the peculiarity of the functioning of the autonomic nervous system. However, constant dispensary observation to rule out progression pathological changes. Incomplete block of the left leg of the bundle of His is never a variant of the physiological norm and requires adequate treatment in view of the danger of this condition.

Primary signs and classic symptoms of incomplete bundle branch block

Primary signs of incomplete blockade of the right leg of the bundle of His may not appear and the patient feels completely healthy. Severe clinical symptoms may occur with complete blockade of the left bundle branch block and require urgent medical care. In most cases, there are manifestations of the disease that provokes the development of this pathology - these are:

shortness of breath physical activity and at rest;
sensation of palpitations and violations of its rhythm;
muscle weakness and fatigue;
and dizziness;
heart rhythm disturbances;
pain, feeling of heaviness in the chest.

The diagnosis is based on the result of an ECG, in controversial cases Holter monitoring is indicated. Confirmation of the diagnosis is carried out using ultrasound and computed tomography.

At sudden appearance symptoms, you should immediately call an ambulance team, as this may indicate the development of ischemia in back wall myocardium (heart attack). The danger to the life of the patient is a three-beam partial and complete blockade of the legs of the bundle of His, it may be accompanied by the development of Morgagni-Edams-Stokes attacks. During such attacks, the blood supply is disrupted. cerebral structures, the patient suddenly loses consciousness, he has a sharp decrease in heart rate. Probability lethal outcome very high. This condition is associated with a complete lack of synchronization of the work of the atria and ventricles. Against this background, a pathological focus arises. nervous excitement in myocardial tissues. It can provoke an attack of atrial fibrillation and ventricular paroxysm. Bradycardia appears with a heart rate of less than 40 beats per minute.

Diagnosis is based on ECG results. If for the first time a blockade of the left leg of the His bundle is detected, then the patient is urgently sent to a specialized hospital with the possibility of resuscitation. Additional examinations are carried out to identify the disease leading to the blockade. Adequate supportive treatment with the help of pharmacological drugs is prescribed. With incomplete blockade of the right leg of the bundle of His, treatment is often not required, but the patient is recommended to have an ECG performed regularly (at least 2 times a year).

On the ECG, the blockade of the bundle branch of His can manifest itself in the following variations;

in V1 and V2 of the right leads, pathological Rsr complexes appear, and in leads V5 and V6, the QRS complex due to the wide S wave is more than 0.12 s.
V5,V6, I with deformed complexes without a Q wave and splitting of the apex of R indicates blockade of the left leg;
with a total lesion of three legs, pronounced signs of antrioventricular blockade appear.

Patients are assigned a set of diagnostic examinations:

a biochemical detailed blood test reveals an imbalance of trace elements, elevated cholesterol levels;
ultrasound reveals the expansion of the heart muscle, conduction disturbance;
daily monitoring will tell about the form of the blockade;
transesophageal cardiography is used in controversial situations.

Possibilities of treatment of bundle branch blockade in modern conditions

AT modern conditions at high level development of cardiology the condition is quite successfully treated. But the main measures are aimed at eliminating the pathogenic factor (the underlying disease). Treatment options for bundle branch block depend on general condition patient, a factor preceding the development of pathology, the presence of concomitant diseases of the cardiovascular and respiratory systems.

Treatment of incomplete blockade of the right leg of the bundle of His is usually not carried out, the condition of the patients does not suffer, it is possible to independently restore the violation of the conduction of the nerve impulse. In the case of a two-beam blockade, the following pharmacological preparations can be used:

vitamin complexes (nicotinic acid and B vitamins);
improving blood supply to the heart muscle ("Mexidol", "Carnitine", "Preductal");
restoring the function of nerve conduction (motherwort, valerian, "Afoobazol");
antiplatelet agents to reduce the risk of blood clots (aspirin, chimes, cardiomagnyl);
statins to normalize blood cholesterol levels;
cardiac glycosides and nitrates;
drugs that normalize blood pressure levels.

Continuous intake of potassium and magnesium supplements is recommended, vitamin complexes, antiarrhythmic drugs if there is evidence. At infectious processes prescribed antibiotics a wide range actions.

In severe cases, emergency surgery is indicated to install a pacemaker. An artificial pacemaker increases the patient's life expectancy to the physiological norm and significantly improves his quality of life.

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