Intraventricular blockade is a disease characterized by disturbances in the conduction of electrical impulses through the ventricles of the heart, due to the influence of various factors on the heart, but these factors may not exist. This pathology can develop in patients of different ages. In most cases, the disease is diagnosed in old age. Blockades can also occur in children, about 5 out of 100,000.
Features of the disease
To understand how and for what reasons intraventricular blockade develops, it is important to understand that in the myocardial system, which provides consistent, continuous and rhythmic electrical excitation of all cardiac structures, there are isolated muscle cells called Purkinje fibers and His bundles.
First education presentedcardiomyocytes, which are characterized by increased electrical excitability, while located in the ventricles. The left and right branches are called legs, the last of which has posterior and anterior branches. Decreasing in diameter, they seem to break up into a huge number of small branches, which are the Purkinje fibers.
Due to all sorts of organic or functional changes in the heart, obstacles appear in the path of electrical signals. In this case, the impulse does not pass further along the ventricles of the heart (in a particular situation). The areas located below, because of this, cannot contract and be excited. This becomes visible on the cardiogram.
Place of manifestation
Intraventricular blockade can occur anywhere in the ventricles. Therefore, the resulting violations are divided into non-specific and blockade of the bundle of His. Each of these subtypes has its own ECG criteria.
It is noteworthy that intraventricular blockade can develop even in an absolutely he althy person, without affecting his well-being. But it is still considered conduction disturbances along the right branch. When registering the left hemiblock, as well as with two- or three-bundle blockade of the terminal branches, it is considered that there is some kind of cardiac pathology.
Reasons
Causes of blockade of intraventricular conduction, as a rule, appear already in childhood. Diseases due to which this disorder develops can be asright and left hemiblock. In addition, blockades of terminal branches can have an effect.
These diseases include: cardiomyopathy, myocarditis, violations of the architectonics of the heart due to acquired or congenital defects, cardiosclerosis, heart tumors. But you should not panic ahead of time, as in both children and adolescents, incomplete and even complete blockade of the right leg is considered a normal condition, often occurring against the backdrop of a he althy heart.
In adulthood and old age, intraventricular heart block develops for completely different reasons. Almost half of all cases are associated with atherosclerotic lesions of the artery that feeds the myocardium in the area of the conducting bundle. This causes myocardial ischemia. In addition to chronic ischemia, acute myocardial infarction leads to this problem.
About a third of all cases are due to arterial hypertension. Also, congenital heart defects and rheumatism can be a common cause of intraventricular blockade.
Regardless of age, blockades are provoked by alcohol poisoning or its surrogates, hyperkalemia, as a rule, in renal failure, chest injuries, excessive use of certain drugs. For example, intraventricular blockade develops in case of poisoning with potassium-containing and some psychotropic drugs.
Symptoms
Often, this disease is asymptomatic. If there are any signs of intraventricular blockade, then they are due to the underlying pathology that led to this blockade. For example, in myocardial ischemiaheadaches appear, usually in the back of the head, retrosternal pain. Myocarditis is manifested by shortness of breath and discomfort in the chest.
If a patient has intraventricular block on the ECG, which is accompanied by certain suspicious complaints, then the patient should be urgently examined for cardiac pathologies.
Attention at full blockade
Special attention should be paid to the complete blockade if it occurs for the first time, and is also accompanied by pain in the left side of the chest or sternum. The fact is that it is almost impossible to recognize a complete left blockade on a cardiogram. For this reason, if a complete left blockade occurs, which is accompanied by burning or pressing pains in the chest, the patient must be checked for acute myocardial infarction, hospitalized as soon as possible in a cardiological hospital.
Non-specific intraventricular block, as a rule, also does not cause discomfort to the patient, but in most cases is accompanied by symptoms that can be attributed to the causative disease.
Diagnosis
In most cases, it is possible to diagnose this blockade only by making a cardiogram. A sign of right intraventricular blockade on the ECG is an expanded and altered M-shaped complex. At the same time, a jagged and deep tooth is observed along the left branches. Complete blockade differs from incomplete blockade in the duration of the complex. At fullblockade, the complex will be more than 0.12 s, and if it is incomplete, it will be below this indicator.
A sign of left intraventricular blockade on the ECG in an adult will be a deformed and dilated ventricular complex along the left chest leads. On the right, a jagged prong is found.
Local blockade of terminal branches
Local terminal branch block, also called local intraventricular block, may also develop. This type is usually caused mainly by acute infarction. Focal intraventricular block is characterized by an acute "damage block", which is represented by necrotic cardiomyocytes. They occur when there are obstacles in the path of electrical impulses, there is a lack of growth of the R wave to the fourth thoracic branch.
Intra-infarction local intraventricular blockade is formed right inside the area of myocardial necrosis, manifested by the splitting of the pathological Q wave. They are observed in the leads that are most characteristic of the affected area. Finally, peri-infarction local intraventricular blockade on the ECG in an adult can be identified by the focus of necrosis of cardiomyocytes. It appears as a jagged and deformed tooth.
It is important to remember that with local intraventricular blockade on the ECG it is impossible to see the Q wave. Its appearance clearly indicates the presence of acute myocardial infarction, which is veiled on the cardiogram by just this blockade.
Additional examinations
When diagnosingblockade, the patient, as a rule, requires additional examinations. For accurate and correct diagnosis, cardiologists are advised to use one or all of these three methods.
Ultrasound of the heart or echocardioscopy. This procedure is prescribed if there is a suspicion of myocarditis, heart disease, myocardial infarction. If the patient denies the fact of inpatient treatment, Echo-CS is considered mandatory, since otherwise the patient may suffer a heart attack on his legs, which will fatally affect his he alth.
Another way is coronary angiography. It is done to assess in detail the patency of the coronary arteries, as well as to determine whether there is a need for bypass or stenting.
Finally, 24-hour Holter ECG monitoring is often prescribed. It is especially useful for non-permanent blockade. This may be due to tachy-dependent blockade, that is, tachycardia, which manifests itself and aggravates during physical exertion.
Do I need to treat the blockade?
Given that this disease is often asymptomatic and does not always indicate cardiac pathology, many are wondering if it is worth treating at all.
According to the recommendations of doctors, treatment of blockades of this type is required only when the patient really has a pathology of the cardiovascular system, which leads to this problem.
For example, in acute myocardial infarction, surgery or therapy with conservative methods is recommended. In the latter case, analogues are assignednitroglycerin, analgesia with narcotic analgesics, massive antiplatelet and anticoagulant therapy. If myocarditis is established, anti-inflammatory therapy is carried out, and in case of cardiosclerosis, cardiac glycosides and diuretics are prescribed, especially if the disease develops against the background of chronic heart failure.
When a heart defect is the cause of the blockage, surgical correction is needed.
Danger of blockade
It should be understood that not every intraventricular block is a real danger. For example, if it is incomplete and single-beam, then you should not pay attention to it at all, especially if it is not provoked by some underlying disease.
Two-beam blockade in most cases is transformed into a three-beam blockade. The latter leads to complete blocking of conduction between the ventricles and atria. In this case, seizures, loss of consciousness are possible. In this situation, the life of the patient is in danger. There is a possibility of sudden cardiac arrest and death.
Possibility of death
Therefore, the most to be feared is a two-beam His blockade, which is combined with symptoms of a major cardiac disease. In this case, it is necessary to closely monitor the patient's condition, as there is a possibility of death.
When signs of second- or third-degree AV block appear on the cardiogram, the doctor decides to install a pacemaker. It is important that he beimplanted even in patients who do not experience severe seizures, as the threat to their lives still remains.
It should be noted that, in addition to AV block, intraventricular problems of this property cause ventricular fibrillation, ventricular tachycardia, which can also be fatal.
Prevention
In this case, the method of preventing sudden death from heart disease due to rhythm disturbances is actively practiced.
In fact, this type of prevention consists in regular visits to a cardiologist, an electrocardiogram, as well as a timely and prompt decision on the implantation of a pacemaker, if necessary.
As a preventive measure against this disease, as well as in order to generally reduce the likelihood of cardiovascular pathologies, it is recommended to avoid unpleasant stressful situations in life, flatly stop drinking alcohol and smoking, strive to lead a he althy lifestyle, exercise moderately physical education and sports.
Be sure to take medications, but in no case self-medicate, following the recommendations of your doctor in everything.
Doctor Visit
After suffering a heart attack or other serious cardiac pathology, it is necessary to regularly visit a cardiologist, at least in the first six months. This will fix your condition, identify complications, if any, and quickly eliminate them.
It is worth noting separately that any of the types of this blockade on the initialstage requires increased attention, mandatory consultation with your doctor.
First of all, you should go to a therapist or a cardiologist who will be able to advise you whether you really should be afraid of this disease, what examinations to undergo, in what way to build your therapy. After all, as we have already noted in this article, this ailment can be both completely harmless and seriously threaten your life and he alth. In the latter case, inpatient treatment will be required, possibly surgery.
