Cardiac pacemaker. Installing a pacemaker

In medical practice Increasingly, there are patients for whom a pacemaker is vital necessity. The device helps to cope with heartbeat disorders that would previously lead to disability and early death patient.

Cardiac disorders inevitably lead to the loss of functionality of others. internal organs, including the central nervous system, due to lack of oxygen. A pathological condition can develop with a too slow pulse rate (bradycardia), arrhythmia complicated by tachycardia, and organ blockade, in which the conduction of electrical impulses fails.

The need for a pacemaker and indications for installation occur in the following diseases:

• Weak sinoatrial node syndrome, in which the heart rate drops to 40 or less. It also includes sinus blockade, bradycardia and bradyarrhythmia (attacks of reduced rhythm frequency are replaced by episodes of tachycardia).
• Atrioventricular blockade (impaired atrioventricular conduction) 2-3 degrees.
• Pathology of the carotid sinus - plummet the frequency of heart beats during irritation of the place of expansion of the internal carotid artery. May be provoked active movement head or squeezing the neck with clothing. Manifested severe dizziness and fainting.
• The need for drug therapy(for example, "Amidarone") for normalization contractile function hearts with various blockades and arrhythmias.
• Other types of bradycardia, which are accompanied by convulsions and / or loss of consciousness due to a short-term complete stop of the electrical system of the heart (asystole).
• Paroxysmal ventricular tachycardia.

• Atrial fibrillation.
• Regular cases of extrasystoles with high probability transition to ventricular fibrillation, left ventricular failure, often resulting from a heart attack.

The installation of a pacemaker is indicated in cases where it is impossible to cope with life-threatening conditions for the patient. medical methods.

What are pacemakers?

To have an idea about the installation method and the types of devices, it is necessary to understand what a pacemaker is and what is the principle of its operation.

A pacemaker (pacer), also called an artificial pacemaker, is a device that supports or enforces normal frequency heart rate, suppresses other foci of excitation of the impulse and monitors the patient's own pulse.

The structure of the EX

Modern models of artificial pacemakers resemble mini-computers: they consist of electrodes, a complex microcircuit and a battery, which allows them to work on average for about 10 years. New pacemakers are also designed for a long service life - up to 12-15 years.

With the help of a microcircuit, the device recognizes the electrical potential of the myocardium - in other words, the cardiogram. Electrodes with sensitive head are implanted into the thickness of the heart muscle, transmitting information about impulses and returning electric charges, normalizing the beat rhythm.

The dimensions of the instrument vary depending on the model and functions, and average weight is about 50 g. Setting up the EKS is performed by a computer programmer within the medical institution where the operation was carried out to implement it.

Classification

Pacemakers are divided by purpose and the number of electrodes. By purpose, they are classified into:

• Pacemakers (pacemakers), which are used for bradycardia to ensure the normal rate of blood ejections.
• Cardioverter-defibrillators, which, in addition to the function of a pacemaker with rare contractions of the heart, are able to recognize the state of fibrillation and restore the normal beat rate using a strong electrical discharge of 12-35 J or special stimulation circuits.

According to the number of electrodes, the EX-s are divided into:

• Single chamber. The pacing lead is placed in the left ventricle and initiates contraction of other cavities. It is rarely used, since if the atrial and ventricular rhythms coincide, the blood circulation of the heart is disturbed. Useless for supraventricular arrhythmias.
• Two-chamber. Equipped with two electrodes, which are placed in the ventricle and atrium. Well control and coordinate the rhythm of contractions of the cavities.
• Three-chamber. They are the most optimal and physiological. Three electrodes are located in the two ventricles and the right atrium, respectively. Such models are actively used in dyssynchronous contractions of the left and right ventricles.

Pacing is also classified by duration. EX is installed for the following types impact:

• Permanent. Epicardial implantation is performed only on open heart special devices.

• Temporary. It is used before the installation of a permanent pacemaker, with drug overdose or transient failure heart rate. To stabilize the patient's condition, if necessary, resuscitation is used external or endocardial pacing. Placement of electrodes on the sternum is less effective than conducting them along the central venous catheter directly into the atrium or ventricle.
• Diagnostic. Transesophageal stimulation is used to eliminate attacks of atrial arrhythmias, as well as to check the functionality of the heart in case of suspected paroxysmal tachycardia, pathology sinus node, violation of atrioventricular conduction, ischemic heart disease.

The ability to select the rhythm from the outside allows the use of a pacemaker as a replacement for bicycle ergometry and treadmill test in diagnosing the causes of angina pectoris.

Labeling of pacemakers

For abbreviation three-letter (ICHD) and five-letter (NBG) codes are used. The marking indicates the number of electrodes and the presence of additional functions. The letters of the code sequentially indicate:

1. Localization of implanted electrodes (A - atrial, V - ventricular, D - both cavities).
2. detectable camera.
3. Response to the received impulse (stimulation - I, suppression - T, both functions - D, no response - O).
4. Adaptation to the requirements of the patient's body to the frequency of contractions (load). Rate-adaptive pacemakers are labeled with the letter R.
5. The presence and parameters of other functions in tachycardia.

Contraindications

There are no absolute contraindications for implantation of a heart pacemaker, neither in terms of age, nor in terms of vital signs. The decision is made by surgeons and cardiologists regarding each clinical case. The operation may be recommended even for those patients who are already in the intensive care unit due to a heart attack. This is possible if the cessation of blood supply to a section of the heart muscle is accompanied by complete atrioventricular blockade or severe arrhythmia.

The date of the intervention may be postponed due to several clinical circumstances (indications) if the patient does not need an immediate pacemaker. These include:

• Fever or symptoms of infectious diseases.
• Aggravation chronic pathologies internal organs (asthma, peptic ulcer gastrointestinal tract).
• Mental disorders that exclude normal contact with the patient and reduce the likelihood of successful rehabilitation.

Preparation and tests before the intervention

List of required diagnostic procedures varies depending on the urgency of the operation and the standards of a particular clinic. Commonly performed preoperative and cardiac tests are:

Preparation for the operation includes consultation of the following doctors:

• Arrhythmologist.
• Otolaryngologist and dentist (they exclude or treat foci of infection).
• Other specialists, if available chronic diseases kidneys, central nervous system, endocrine system.

A few days before the intervention, doctors may request that NSAIDs and anticoagulants be discontinued. In parallel with this, it is necessary to lighten the diet, and on the day of the procedure, starting from midnight, do not eat or drink anything.

How is implantation performed?

The cardiac activity stimulator is installed with local anesthesia of the sternum, less often under general anesthesia. The whole procedure lasts 1-2 hours and includes the following steps:

1. After all diagnostic procedures, the patient is taken to the operating room. Local anesthesia of the sternum over the left clavicle is performed.
2. An incision is made in the skin and vein under the collarbone. The electrodes are passed through the vessel to the cavities of the heart. The progress of the detectors is controlled by X-rays.
3. When they reach the right chambers, the surgeon looks for the best place to stimulate by checking the heartbeat parameters on the ECG. Upon completion of the search, the electrodes are fixed in the wall of the organ with "antennae" or a corkscrew-like fastening.
4. After installing the detectors in subcutaneous tissue a bed is being prepared for the EKS case. Having placed the device, doctors connect electrodes to it, stitch the wound and apply sterile dressing. At the site of the seam, a noticeable scar later remains.

After the operation, the arrhythmologist programs the pacemaker by setting the cardiogram recording modes, cardiac muscle stimulation, load analysis parameters and selection of the degree of stimulation activity. Also in the settings, an emergency mode is set, which operates when the battery is low.

Within 6-10 days, the patient is observed in the hospital, receiving therapy from analgesics, anticoagulants and antibacterial drugs.

How long does a stimulator last?

The pacemaker is installed permanently, however, the duration of uninterrupted operation of one source of impulses does not exceed ten years. The service life of the EX is on average 8-10 years: it is determined by the capacity of the battery. After a complete discharge or failure of the stimulator due to non-compliance with safety standards or manufacturing defects, the device must be replaced. Often the electrodes last longer than the generators of electrical impulses, therefore, when reoperation can only install a new titanium case with a chip and a battery.

The warranty covers the first 3-5 years of operation of the device.

What is the cost of the operation?

If it is necessary to implant a heart pacemaker, the cost of the operation can be paid according to the quota, that is, the patient can do it free of charge, excluding the cost of travel, stay in a medical facility and accommodation during preparation for the procedure and rehabilitation. Due to the high demand for pacemakers, scheduled installation is done one by one.

The price of electrostimulators varies depending on the manufacturer and device configuration. Single-chamber pacemakers will cost the patient 10-70 thousand rubles, two-chamber - 80-200, three-chamber - up to 450. The cost of electrodes, as well as the costs of implantation itself, are often considered separately.

Complications

Side effects after surgery, which can lead to a worsening of the patient's condition, are rare. According to statistics, complications are observed in 6.2% of elderly patients (over 65 years old) and 4.5% of people younger than this age. The probability of fatal consequences is orders of magnitude lower than these values. When installing a pacemaker, there is a risk:

• Infectious infections - suppuration of the incision, fistula formation, sepsis.
• Displacement of electrodes-detectors.
• Intracardiac bleeding.
• Stimulation of extracardiac muscles, diaphragm.
• Loss of the analyzing function of the EX, leading to failures of stimulation.
• Edema of the upper limb.
• Pneumothorax.
• Block large blood vessels.
• Fracture detector.
• Early end of battery life.

Most of these complications can be avoided with the correct implantation of the device, the use of quality equipment and adequate post-operative care. To protect yourself, you should pay attention to patient reviews about pacemakers from a certain manufacturer, as well as about operations by a particular doctor.

Lifestyle after surgery

Life with a pacemaker is full and differs from the reality of a healthy person only in a number of aspects. Following the recommendations, the patient can work, do household chores and even get involved in sports.

In this case, it is necessary to observe safety precautions:

• Visit a cardiac surgeon and arrhythmologist once a quarter for 1 year after the implantation of the stimulator, once every six months - during the second and annually - in the future.
• Monitor your health status (well-being, blood pressure, pulse rate).
• Refuse bad habits(alcohol, nicotine), to establish a balance of work and leisure.
• Avoid some diagnostic methods (ultrasound of the sternum, MRI) and physiotherapy (impact magnetic fields warmth).
• Consult with a cardiologist before minimally invasive interventions (electrocoagulation, operations with electric scalpel incisions, fragmentation of stones in internal organs).
• Do not stay near high voltage power sources for a long time.
• Avoid blows to the sternum and falls.
• Mobile phone and sources electromagnetic radiation(including household ones) when using, it is desirable to place it on the other side of the body relative to the device, at a distance of more than 25-30 cm from it.

The patient needs to carry a document confirming the installation of the pacemaker with him: this will avoid detector checks that are dangerous for the operation of the device.

The patient's performance is determined medical commission, taking into account the presence or absence of complications (IHD, CHF). A patient may be given a disability group if work at a particular workplace can cause serious harm to him or the device (contact with electric welding equipment, steel-smelting machines).

The presence of a pacemaker is not absolute contraindication for bearing a fetus. But the patient should be observed by a cardiologist during the entire period of pregnancy and follow all the doctor's recommendations on nutrition and exercise. Childbirth takes place only through caesarean section operation is scheduled.

Physical activity should be moderate, without tension in the sternum. During the rehabilitation period (up to 3 months), sports are prohibited along with any intense loads upper body.

For life banned martial arts due to the risk of blows to the device area, extreme sports, football, rugby, basketball, hockey, shooting, bodybuilding with weights on the pectoral muscles.

Bath and sauna are allowed only after consultation with a doctor in the absence of complications, after the end of rehabilitation. Visits should be infrequent and gentle.

Forecast

The use of pacemakers in medicine has made it possible to significantly increase the life expectancy of patients with arrhythmia, heart block, and weakness of the sinus node. With bradyarrhythmias and supraventricular tachycardias, the efficiency of device installation reaches 100%. With atrial and ventricular fibrillation, the pacemaker helps 80-99 patients out of 100.

Knowing not only your own indications for the installation of a pacemaker, but also what it is, what advantages and disadvantages the operation for its implantation brings, you can more confidently accept correct solution. EX allows you to eliminate unpleasant symptoms cardiac pathologies and in time to stop life-threatening conditions.

In polyclinics, doctors are increasingly confronted with patients for whom life with a pacemaker has become normal domestic problem. They do not complain about their health, continue to work in their specialty, cope with moderate physical exertion.

It is wonderful when a person who was previously bedridden due to arrhythmia attacks receives a pacemaker to get rid of the pathology.

Purpose of the device

At healthy people contraction of the heart muscle occurs under the influence of transmission nerve impulses. The path passes from the sinus node in the right atrium to interventricular septum and further diverging deep into the fibers. Thus, the provision correct rhythm.

The coordinated activity of the main node with the sympathetic and vagus nerves allows you to adapt the number of contractions to specific situation: during physical work, stress, the organs and the brain need more oxygen, so the heart should contract more often, while sleeping, a rarer rhythm is enough.

Arrhythmias occur for various reasons. Electrical impulses change direction, additional foci appear, each of which "claims" to be a pacemaker.

Medications do not always lead to successful outcome. There are cases when a combined pathology in a person precludes the use of medications. In such a situation, the installation of a pacemaker comes to the rescue. He is capable of:

• "force" the heart to contract in the right rhythm;
• suppress other foci of excitation;
• monitor the person's own heart rate and intervene only in case of irregularities.

How is the device set up?

Modern types of pacemakers can be compared to a small computer. The device weighs only 50 g. The coating is made of titanium compounds. A complex microcircuit and a battery are built inside, providing autonomous power supply to the device. The life of one battery is 10 years. This means that you will have to replace the pacemaker with a new one. The latest modifications of the device work from 12 to 15 years.

Strong electrodes come from the device for direct contact with the myocardium. They transfer the discharge to muscle tissue. The electrode is equipped with a special sensitive head for sufficient interaction with the heart muscle.

All materials from which the device is made are suitable for the body, do not have allergic properties, do not deteriorate during body movements, heart contractions.

Pacemaker operation

To understand how a pacemaker works, imagine an ordinary battery, which is often used in everyday life. We always set it depending on the poles of the charge. In the device, a discharge occurs only when the heart's own contractions become rare with bradycardia or chaotic with a disturbed rhythm.

The necessary rhythm is imposed on the heart by the force of the discharge, therefore the device is also called an artificial pacemaker. In older models, a significant disadvantage was the setting of a constant number of contractions, for example, 72 per minute. Of course, this is enough for a calm, measured life, slow walking. But it is not enough in cases of acceleration of movements, if you have to run, during unrest.

A modern heart pacemaker "does not offend", adapts to its needs and physiological fluctuations in the frequency of contractions. Conductors not only transmit impulses to the myocardium, but also collect information about the established heart rate. The attending physician can check the operation of the device in specific situations.

Varieties of devices

The need for an artificial pacemaker can be temporary or permanent. Temporary pacemaker placement is necessary for the duration of the patient's stay in the hospital, to treat short-term problems:

• bradycardia after heart surgery;
• elimination of overdose medicines;
• relieving an attack of paroxysmal flicker or ventricular fibrillation.

Pacemakers for the treatment of long-term problems with arrhythmias are produced by different companies, they have their own differences. In practice, they can be divided into three types.

There are no obstructions to blood outflow when electrodes are placed in 2 chambers

Single-chamber - differs in one single electrode. It is placed in the left ventricle, while it cannot influence atrial contractions, they occur on their own.

Model disadvantage:

• in cases of coincidence of the rhythm of ventricular and atrial contractions, blood circulation inside the heart chambers is disturbed;
• not applicable for atrial arrhythmias.

Dual-chamber pacemaker - endowed with two electrodes, one of them is placed in the ventricle, the second - in the atrial cavity. Compared to single-chamber models, it has advantages because it is able to control and coordinate both atrial and ventricular rhythm changes.

Three-chamber - the most optimal model. It has three electrodes that are implanted separately into the right chambers of the heart (atrium and ventricle) and into the left ventricle. This arrangement leads to the maximum approximation to physiological pathway the passage of a wave of excitation, which is accompanied by the support of the correct rhythm and the necessary conditions for synchronous contraction.

The choice of the desired model is determined by the type of arrhythmia, the patient's condition. The attending cardiac surgeon can always advise the patient and relatives on the optimal therapeutic effect device in a particular situation.

Why are devices coded?

For convenient use different models without detailed descriptions destination, a letter classification is used, proposed jointly by American and British scientists.

• the value of the first letter determines in which parts of the heart the electrodes are implanted (A - in the atrium, V - in the ventricle, D - in both chambers);
• the second letter reflects the camera's perception of an electric charge;
• the third - the functions of starting, suppressing, or both;
• the fourth - indicates the presence of a mechanism for adapting abbreviations to physical activity;
• fifth - includes a special functional activity with tachyarrhythmias.

The most common types are VVI and DDD.

When coding, they do not pay attention to the last two letters, so you have to additionally find out the functions of the device.

Indications for implantation of an artificial pacemaker

Persistent cardiac arrhythmias have many causes. Most often, severe heart attacks and widespread cardiosclerosis lead to failures. These changes are especially severe in old age, when the body no longer has enough strength to restore and compensate for losses.

Not less often, cardiac surgeons have to deal with dangerous attacks without a clear cause (idiopathic arrhythmias).

• confidence in the weakness of the sinus node;
• the presence of such types of arrhythmias as extrasystole, paroxysmal tachycardia, atrial fibrillation, if developing frequent seizures ventricular fibrillation;
• complete with bouts of loss of consciousness;
• the need to take drugs against the background of the blockade to support the contractile function of the myocardium in cases of heart failure.

The operation is indicated if medical methods fail to cope. There are no contraindications for this manipulation.

How is temporary pacing performed?

There are simplified models for temporary pacing. Depending on the localization of the place where the electrodes are placed, there are types of stimulation:

• endocardial,
• epicardial,
• outer,
• transesophageal.

The most effective is the endocardial option. The device is placed next to the patient, the electrode as a probe is inserted through the catheter into subclavian vein under the control of X-ray or ultrasound equipment. On the electrocardiogram correct installation rise in the ST interval is recorded. Bursts of energy and ECG-picture are controlled by the monitor.

In the case of external stimulation, adhesive electrodes are applied to the patient's skin. It is carried out when it is impossible to use the intracardiac method.

Epicardial installation - make special electrodes only on the open heart during cardiac surgery

Intraesophageal stimulation is limited to the temporary elimination of supraventricular arrhythmias.

After the patient is taken out of dangerous state the electrodes are removed and the heart is allowed to work at its own pace.

Progress of permanent pacemaker implantation

The operation to install a pacemaker for a long time is performed without opening the chest. use local anesthesia. Through an incision in the subclavian region, the electrodes are inserted through the subclavian vein into the heart chambers, then under the skin to pectoral muscle hem the device itself.

Checking the correctness of the installation is carried out using X-ray control, a cardiac monitor. In addition, the surgeon needs to make sure that the pacemaker is working and fully captures the atrial impulses in the specified mode.

At the end, several sutures are placed on the skin and the incision site is closed with a sterile napkin.

The replacement of the pacemaker is carried out after the expiration of the service life of the device according to the same principle as the initial installation.

How to evaluate the correct operation of the pacemaker?

The frequency of the imposed rhythm is monitored on the monitor, it must correspond to the programmed one. All artifacts (vertical bursts) must be accompanied by ventricular complexes. Insufficient frequency is possible when the battery is discharged. Contractility hearts are easy to check by a clear pulse on the ulnar artery.

If the natural frequency of the rhythm is detected higher than programmed, a reflex increase in tone is used. vagus nerve(massage of the carotid zone or Valsalva test with straining while holding the breath).

During the operation, some actions of the medical staff are important:

• carrying out electrocoagulation of vessels to stop bleeding can affect the operation of the pacemaker, therefore it is recommended to monitor the short pulsed effect of the coagulator;
• anesthesiologists know the list of drugs that can mask electrical impulses from the myocardium and block pacing;
• if the patient's condition is accompanied by a violation of the concentration of potassium in the blood, the electrophysiological properties of myocardial cells are disturbed and the threshold of sensitivity to stimulation increases, this should be taken into account when selecting parameters.

How is the postoperative period?

During the rehabilitation period after implantation of the stimulator, the patient needs to get used to slight restrictions in physical activity, movements involving the muscles of the shoulder girdle, and constant “listening” to the heart.

If the skin at the site of the seam is inflamed, moderate pain, fever are possible. Malfunctions in setting up the device can be signaled by increased shortness of breath, the appearance of pain in chest growing weakness.

It is difficult to predict in advance how long a patient will live with the installed device. It is necessary to use the average terms indicated in the instructions.

Indications for the installation of a pacemaker (or artificial pacemaker, IVR) are absolute and relative. The indications for the installation of a pacemaker are said every time there are serious interruptions in the rhythm of the heart muscle: long pauses between contractions, a rare pulse, atrioventricular blockade, syndromes hypersensitivity carotid sinus or weakness of the sinus node. Patients with such diseases are those people who need to have a pacemaker installed.

The reason for the occurrence of such deviations may be a violation of the formation of an impulse in the sinus node ( congenital diseases, cardiosclerosis). Bradycardias usually occur in one of four possible causes: sinus node pathology, AV node pathology (AV blocks), pedicle pathology (fascicular blocks) and autonomic depression nervous system(manifested by neurocardial syncope).

Absolute indications for an operation to install (use) a pacemaker include the following diseases:

• bradycardia with clinical symptoms(dizziness, fainting - syncope, Morgagni-Adams-Stokes syndrome, MAC);
• recorded decrease in heart rate (HR) to values ​​less than 40 during physical exertion;
• episodes of asystole on the electrocardiogram (ECG) lasting more than 3 seconds;
• persistent atrioventricular block II and III degree in combination with two or three-beam blockade or after myocardial infarction in the presence of clinical manifestations;
• any kind of bradyarrhythmia (bradycardia), life threatening or health of the patient and in which the heart rate is less than 60 beats per minute (for athletes - 54 - 56).

Indications for setting a pacemaker are rarely heart failure, in contrast to the arrhythmias of the heart that accompany it. In severe heart failure, however, we can talk about non-synchronous contractions of the left and right ventricles - in this case, only the doctor decides on the need for an operation to set up a pacemaker (pacemaker).

Relative indications for pacemaker implantation:

• atrioventricular block II degree type II without clinical manifestations;
• atrioventricular blockade of the III degree in any anatomical area with a heart rate at a load of more than 40 beats per minute without clinical manifestations;
• syncope in patients with two- and three-beam blockade not associated with ventricular tachycardia or complete transverse blockade, with the inability to accurately determine the causes of syncope.

In the presence of absolute readings before the implantation of a pacemaker, the operation is performed on the patient as planned after examination and preparation or urgently. in this case no. In the presence of relative readings on the implantation of the stimulator, the decision is made individually, taking into account, among other things, the age of the patient.

The following diseases are not indications for the installation of a pacemaker by age: atrioventricular blockade of the 1st degree and atrioventricular proximal blockade of the 2nd degree of type I without clinical manifestations, drug blockades.

It should be noted that each country in the world has its own recommendations for the installation of pacemakers. Russian recommendations largely repeat the recommendations American Association cardiologists.

When is a pacemaker placed on the heart?

A pacemaker is placed only in cases where there is a real risk to the life and health of the patient. Today, both single-chamber devices and two- and multi-chamber devices are used. Single-chamber "drivers" are used (to stimulate the right ventricle) and in sick sinus syndrome, SSS (to stimulate the right atrium). However, more and more often they put it with SSSU.

SSSU manifests itself in one of four forms:

• symptomatic - the patient has already lost consciousness or had any dizziness;
• asymptomatic - the patient has bradycardia on the ECG or daily monitoring(on the "holter"), but the patient does not express complaints;
• pharmacodependent - bradycardia is present only against the background of usual doses drugs with a negative chronotropic effect, (antiarrhythmic drugs and beta-blockers). With the abolition of drugs, the clinic of bradycardia completely disappears;
• latent - there is no clinic or bradycardia in the patient.

The last two forms are recognized initial stage sinus node dysfunction. The patient can wait up to several years with the implantation of the pacemaker, but this is only a matter of time - the operation becomes from an emergency planned one.

What other heart conditions are treated with a pacemaker?

In addition to the heart diseases described above, a pacemaker is used to treat dangerous arrhythmias: ventricular tachycardia and ventricular fibrillation to prevent sudden cardiac death. In the presence of atrial fibrillation, indications for the installation of a pacemaker are urgent (in this case, the patient is already losing consciousness or there is a tachybradyform). And the doctor cannot prescribe drugs to increase the rhythm (risks of fibrillation attacks) and cannot prescribe antiarrhythmic drugs(intensifies the brady component).

Risk sudden death in case of bradycardia with attacks, MAC is considered low (according to statistics - about 3% of cases). In patients diagnosed with chronic bradycardia, the risk of syncope and sudden death is also relatively low. With such diagnoses, the installation of a pacemaker is largely preventive in nature. Such patients, due to adaptation to their heart rate, rarely complain of dizziness or fainting, but they have a whole layer concomitant diseases, from which the installation of the IVR will no longer save.

Timely implantation of a pacemaker helps to avoid the development of brady-dependent heart failure, atrial fibrillation, arterial hypertension. According to experts, at present, up to 70% of operations are carried out precisely for preventive purposes.

With a transverse blockade, implantation of the pacemaker is mandatory, regardless of the cause, symptoms, nature of the blockade (transient or permanent), heart rate. Here are the risks lethal outcome for the patient are extremely high - the IVR setting allows you to increase the survival rate of patients to values ​​close to those of healthy people. The operation is an emergency one.

In two cases:

• complete blockade that appeared during acute infarction myocardium;
• complete blockade resulting from cardiac surgery

it is possible to wait up to 2 weeks (it is possible to resolve the problem without installing the EX). With congenital complete blockade, indications for implantation of a pacemaker are already in adolescent children. Congenital blockade develops in utero (the cause is mutations of 13 and 18 chromosomes). In this case, children do not have MAS attacks, because. they are fully adapted to their bradycardia.

Unfortunately, bradycardia only increases with age, by the age of 30 (the average life span of a patient with a similar disease) Heart rate may drop to 30 beats per minute. The installation of a stimulator is mandatory, it is planned. Emergency implantation is performed in case of syncope. If the heart rate is critical, then the operation is performed even at the age of several days or months.

Treatment of blockade in a child depends on whether it is congenital or not. If it is congenital, then it is registered at the maternity hospital, and the diagnosis is known even during pregnancy. If acquired, it is considered that it was obtained as a result of the myocardium. In the second case adolescence not expected - the pacemaker is implanted regardless of age.

The beginning of the 20th century was marked by the rapid development of technology in all areas of human life.

innovative medical research conducted in the 1920s showed the ability of the myocardium to contract under the influence of electric current impulses.

The essence of the research was able to revolutionize the treatment of certain heart diseases, which was proved by the external device for maintaining the rhythm created in 1927.

However, due to the large size and relatively small resource of electronic components of that time, the development of pacemakers was frozen for decades.

The device in its modern sense was created only in 1958 by Swedish scientists and was named Siemens-Elema. Since then, the design and principle of operation of pacemakers have been improved every year - the devices become more functional, reliable and durable.

Purpose and device of the device

To understand how a modern pacemaker works, you need to understand what it is. A pacemaker (EX) or, as it is also called, an artificial pacemaker (IVR), is a microprocessor-based device equipped with an independent power source and located in a sealed metal case, most often made of a titanium alloy.

The design of the device includes:

1. Frame- serves to accommodate the internal elements of the pacemaker and isolate them from body tissues.
2. Control and communication unit– necessary for coordination of modules operation, exchange of information with control and diagnostic devices.
3. memory block– stores statistical information about the operation of the device.
4. Sensor block- is able to detect changes in the work of the heart and correct the effects of the pacemaker.
5. Working block- generates and transmits electrical impulses to the heart.
6. Battery- serves as a power source for the remaining elements of the pacemaker, is equipped with mechanisms to save energy and disable non-basic functions when the charge drops below the threshold level.

The functions of the pacemaker are to perceive the heart's own rhythm, detect pauses and other failures in its work and eliminate these failures by generating impulses and transmitting them to the corresponding chambers of the heart.

If the own rhythm is stable and corresponds to the needs of the body, impulses are not generated.

An optional feature of some high-tech stimulants is the prevention of arrhythmia, tachycardia and other disorders through special work programs.

What are pacemakers?

IN currently There are many varieties of pacemakers that differ from each other in design, functionality and other criteria. Classification of devices can be carried out according to various signs, but the main ones are the design features that characterize the specifics of stimulation.

Depending on them, there are:

• Single chamber pacemakers - affect one atrium or one ventricle;
• Two-chamber - affect the atrium and ventricle at the same time;
• Three-chamber - affect both atria and one of the ventricles;
• Cardioverter-defibrillators (ICD, IKVD) - are used in case of high risk complete cessation of circulation.

To understand in which cases a particular pacemaker model should be used, its letter code, which takes into account design features and functionality of the device.

It includes 3-5 letters of the Latin alphabet, which, depending on serial number on the label indicate:

1. Stimulated camera.
2. Camera detected by the device.
3. The nature of the response of the heart to an impulse.
4. Frequency adaptation parameters of the device.
5. Type of device response to tachycardia.

The main letters used in the labeling of the pacemaker are the first letters English words: Atrium (atrium), Ventricle (ventricle), Dual (two, both), Single (one), Inhibition (suppression), Triggering (stimulation), Rate-adaptive (rate adaptation). The final code that marks the types of pacemakers may look like this: AAI, VVIR (aka PEX), DDDR, etc.

Considering the classification of IVR, one cannot ignore the temporary pacemaker. It is an external device that is connected to the patient's heart by a resuscitator in the event of a sudden cessation of natural cardiac activity or frequent dangerous fainting.

Indications for installation

The most common heart conditions for which a pacemaker is recommended are:

• Arrhythmia;
• Sick sinus syndrome;
• Atrioventricular block.

Arrhythmia is pathological condition, which is characterized by a change in the frequency and sequence of stages of excitation and contraction of the heart. When arrhythmia is disturbed normal functioning body and there are a number of serious complications.

Arrhythmias can be caused different reasons but the most common are:

• Ischemic heart disease;
• Heart failure;
• Cardiomyopathy and myocarditis;
• Heart defects (both congenital and acquired);
• Mitral valve prolapse;
• Toxic effects, including smoking, alcoholism, drug use;
• Mixed effects, manifested by atrial fibrillation or ventricular fibrillation (heart rate increases to 250 beats / min. or more).

Not everyone has a pacemaker listed cases. Some violations allow you to do without surgical intervention, acting on the source of the problem medicines or other factors.

Sick sinus syndrome (SSS) reflects disturbances in the functioning of the sinoatrial mechanism for controlling the rhythm of heart contractions.

Arrhythmias and blocks associated with SSS include:

• A fall minimum heart rate up to 40 beats / min. and below, and heart rate under load - up to 90 beats / min. and below;
• Pauses between contractions exceeding 2.5 seconds;
• Alternating bradycardia and tachycardia;
• Severe sinus bradycardia;
• Bradysystolic mitral arrhythmia;
• "Migration" of the atrial driver;
• Sinoauricular blockade, etc.

Features of the operation

The operation to install a pacemaker refers to minor surgical interventions and is performed in an X-ray operating room. The first step is to determine the installation location.

The most common options are:

• Left subclavian region– for right-handers, left-handers with tissue damage right side chest;
• Right subclavian region - for left-handers, right-handers with tissue damage on the left side of the chest;
• Other places connected by veins to the chambers of the heart - if classic options for some reason are not possible.

Let's see how the operation goes. The algorithm usually includes the following sequence of actions:

For an experienced surgeon, 20-30 minutes is enough for all this, however, with an atypical installation site or connecting several cameras at once, the time for surgical intervention may increase.

Device installation cost

There is no definite answer to the question of how much such an operation costs - it all depends on the reputation and prices of the clinic, the features of the technologies used in it. In Moscow heart health clinics, the cost of the operation will be from 100 to 600 thousand rubles, in St. Petersburg the price fluctuates - from 60 to 300 thousand. Provincial clinics are ready to do the work for 25-100 thousand rubles.

But it is important to understand that these amounts take into account only the installation of the device. For the pacemaker itself, you will need to pay another 2,500-10,000 dollars.

Patients who are treated under the quota can receive a full range of services for 3500-5000 dollars.

This amount includes:

• Accommodation and maintenance in the clinic;
• The cost of a pacemaker;
• The cost of consumables;
• Payment for the work of doctors and medical staff.

Patients with serious cardiac arrhythmias who have general health insurance are provided with a pacemaker free of charge.

How to live with a pacemaker?

Despite the possibility of returning, in fact, to the old life, a patient with a pacemaker should still adhere to some rules.

The first and main thing is to regularly timely visit a doctor who conducts further monitoring of the patient.

The following sequence of visits is usually assigned:

1. Three months after the installation of a pacemaker.
2. Six months after the first postoperative visit.
3. Once every six to twelve months by agreement with the doctor for a scheduled examination.
4. Unscheduled - in cases of sensation of electrical discharges, the return of symptoms of the disease, the appearance of signs of inflammation at the installation site of the device.
5. After the expiration of the life of the pacemaker declared by the manufacturer (usually it is 6-15 years).

Like any implantable medical device, a pacemaker has its pros and cons. About the pros, that is positive influence a lot has already been said about the device for the work of the heart and the body as a whole. But it's important to remember that living with a pacemaker after surgery means paying attention to details that previously seemed unimportant.

You will have to refrain from such types of work and actions:

Being close high-voltage power lines, powerful wireless transmitters;

Checking with a metal detector and passing through magnetic frames at the airport, shops;

Carrying out MRI, lithotripsy, physiotherapy, as well as ultrasound in the immediate vicinity of the device installation site.

There will also be a number of restrictions in everyday life. Special care should be taken when working with electrical appliances, and especially with powerful power tools, to avoid any electric shock. The mobile phone should be kept at a distance of no closer than 20-30 cm from the place where the pacemaker is installed.

It is also recommended not to bring a camera, player and other portable electronics near the device. Otherwise, patients with a pacemaker live full life, getting rid of the problems associated with a violation of the rhythm of the heart.

In what cases is it necessary to replace the device and how is it carried out?

During a scheduled visit to the doctor, the pacemaker is diagnosed and, if necessary, reprogrammed. However, in some cases it may be necessary to replace the device.

Such cases include:

• End of the warranty period;
• Low remaining battery power;
• Occurrence of unrecoverable faults.

A special case is the replacement of the stimulator to install a more modern and functional model. The process of replacing a pacemaker is similar to the process of installing it, it is also carried out under local anesthesia. During the operation, the condition of the electrodes is monitored and, if necessary, new ones are installed.

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