Setup and Pacemaker Modes

A medical device that maintains a heart rhythm is a complex device made from an inert medical titanium alloy. The device is a kind of mini computer that regulates the heart.

Tincture of the pacemaker, that is, the choice of the optimal mode to stimulate the heart depends on the indications for its installation. Programming is carried out during implantation. Further verification of the EX-setting is carried out at each scheduled cardiologist visit. If necessary, the doctor changes the functional mode of the device.

Pacemaker Modes

Medical devices that support the rhythm of the heart, there are several types:

• Single-chamber - stimulation of the ventricle or atrium.
• Two-chamber - stimulation of the ventricle and atrium.
• Three chambers - stimulation of both ventricles and right atrium.
• Four-chamber - impact on all organ chambers.

There are also wireless cardiac pacemakers and cardioverter-defibrillators. All of them work in different modes of stimulation, ensuring the normal functioning of the heart muscle.

In 1974, a special code system was developed that describes the functions of the EKS. In the future, the encoding began to be used to indicate the mode of operation of the device and consist of 3-5 letters.

1. The first symbol is the heart chamber for stimulation:

• A - auricle.
• V - ventricles.
• D - two-chamber systems acting on the atria and ventricles.

2. The second symbol indicates a camera that is being analyzed by the ECS (instrument sensitivity function). If the device has the letter O, then this indicates that the implant does not work in this mode.
3. The third symbol is the response of an EX to the spontaneous activity of the heart chamber.

• I - inhibition, that is, the generation of a pulse is inhibited by a specific event.
• T - pulse generation starts as a response to an event.
• D - the activity of the ventricles inhibits the impulse of the device, and the activity of the atria triggers the stimulation of the ventricles.
• О - no response to the event, that is, the ECS operates in the asynchronous stimulation mode with a fixed frequency.

4. The fourth letter is frequency adaptation, the answer. R is used if the mechanism has the function of adapting the frequency of stimulation to the physiological needs of the organism. Some EXs have sensors that monitor physical activity and respiration.
5. The fifth symbol is multifocal stimulation of the heart muscle.

• O - the absence of this function in the device.
• A, V, D - the presence of a second atrial or ventricular electrode.

Consider the most common modes of operation of the implant:

• VVI - Single-chamber ventricular stimulation on demand.
• VVIR - single-chamber ventricular stimulation on demand with frequency adaptation.
• AAI - single chamber atrial pacing on demand.
• AAIR - single-chamber atrial pacing on demand with frequency adaptation;
• DDD is a two-chamber atrioventricular bio-controlled stimulation.
• DDDR is a two-chamber atrioventricular bio-controlled stimulation with frequency adaptation.

The choice of the mode of adequate stimulation depends on the indications for the device installation. With low physical activity and no need for constant functioning of the FORMER, select the VVI mode. VVI and VVIR are used in the diagnosis of chronic atrial fibrillation. DDD and DDDR are optimal for AV block, left ventricular dysfunction.

Ddd pacemaker mode

The ECS operating in DDD mode indicates dual chamber atrioventricular bio-controlled stimulation. That is, the pacemaker is fully automatic and has a function of frequency adaptation.

Indications for DDD mode:

• AV blockade.
• Sinusova bradycardia.
• Stop the sinus node.
• Sinoatrial blockade.
• Pacemaker syndrome.
• Tachycardia with a circular motion mechanism.
• Atrial or ventricular premature beats.

Electrodes of the device are located in the atrial and ventricular chambers. Due to this, there is an effective correction of all conduction disorders, provided that there is no permanent arrhythmia. This mode is not set at a constant form of atrial fibrillation or flutter, as well as at slowed down retrograde.

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Pacemaker vvi mode

If the artificial pacemaker is in VVI mode, this indicates single-chamber ventricular stimulation on demand. This set of functions is typical primarily for single-chamber EKS, but other advanced models of pacemakers can work in the VVI mode.

Indications for VVI:

• Persistent atrial fibrillation.
• AV-blockade II and III degree in patients with cerebral pathologies or impaired locomotor function.
• Bradycardia attacks.

VVI begins to work when registering spontaneous depolarization, the frequency of which exceeds the programmed one. In the absence of spontaneous activity of the ventricles, the implant is in the “on demand” mode.

Pacemaker rhythm

Heart rate is completely dependent on the pulses generated in the sinus node. The sinus node is the main driver of the heart rate and parts of the conducting system. Normally, it generates pulses with a frequency of 60-100 beats per minute. Abbreviations occur at regular intervals.

If there is a violation of the time intervals between the individual contractions, this leads to a shortening of the systole (contraction) or a decrease in diastole (relaxation). The processes of stimulation of the heart rhythm are regulated by the endocrine hormones and the autonomic nervous system.

To eliminate problems with a serious disturbance of the heart rhythm, which may have congenital causes or occur due to certain diseases, patients undergo an operation to install an EKS. Pacemaker rhythm supports the physiological work of the heart, preventing various malfunctions. The frequency of contractions is set using the device mode, as is usually within the normal range for a healthy person.

Pacemaker Battery

Artificial heart rate driver is a complex device with many different functions. Its main task is to maintain the normal functioning of the heart. Duration of work EX-depends on the power source. The battery for a pacemaker is a miniature, but capacious battery, which lasts for 3-10 years.

Most instruments are based on a lithium ion battery. In some modern models, a solid type electrolyte based on titanium, platinum or lithium thiophosphate is used as a power source. Batteries are made from materials that are safe for health and life.

When the battery fails, the entire device is replaced. It should also be noted that before the implantation of the EX, the battery is tested for defects. This reduces the need for premature replacement of the device, that is, the re-operation.

Replacing the battery in the pacemaker

The time it takes to replace the battery in the pacemaker depends on the model of the artificial heart rate driver, its functionality and the established stimulation mode.

On average, the service life of the device is 5-10 years. But if the patient has his own heart rate and the ECS is switched on from time to time, then he can work without fail over 10-13 years.

If the battery fails, the patient is undergoing surgery to remove an old pacemaker and install a new device. During surgery, only the body or the body and electrodes can be replaced.

How to charge a pacemaker?

Artificial heart rate driver is a kind of mini computer. It consists of a strong body, electrodes and of course a battery. It is from the capacity of the power source depends on how long the device will last.

• The ECS is implanted under the skin in the clavicle and connected with wires to the heart muscle. It is not possible to connect a cord and recharge it to an already inserted pacemaker.
• Miniature size and optimal functioning mode, allow the device to operate smoothly for 5-10 years.
• A signal that the battery is coming to an end is a violation of the established stimulation mode. The process of replacing the battery is carried out with the removal of the device case and sewing in a new one.

That is, to date, there is no possibility of wireless charging EX. But in the 1960s, several models were created that had a power source based on the radioactive isotope - plutonium. The half-life of this element is about 87 years.

The idea of releasing pacemakers with such a battery was quickly abandoned. This is due to the high toxicity of plutonium and the need to extract the apparatus after the patient’s death, which entailed the problem of further isotope utilization. Another obvious reason for the absence of an eternal battery is the wear of the electrodes and the housing itself.

Pacemaker malfunction

Most often, failures in the work of an artificial heart rhythm driver are associated with the recognition of impulses or stimulation of organ chambers. The malfunction of the ECS occurs due to the following reasons:

• Battery drain.
• Offset electrode device.
• Violation of the integrity of the electrode.
• Fibrous changes around the end of the electrode.
• Perforation of the myocardium by the electrode.
• High threshold stimulation.
• Exposure to external factors: electromagnetic and magnetic radiation, mechanical trauma.

Problems with the pacemaker are detected with a pulse artifact without a seizure, or in the absence of artifacts with severe bradycardia. Observed a change in the frequency of stimulation, impaired synchronization function. The increase in the refractory period of the EKS is possible.

To restore the normal operation of the ECS, a comprehensive diagnosis of its state and reprogramming is carried out. In some cases, the device is changed to a new one.