Bradyarrhythmias is a term that describes too slow heart rhythms, and therefore low heart rate, then the professional term is bradycardia, i.e. a heart rate of less than 60 per minute. Bradyarrhythmias are also often characterized by irregular heartbeat. Find out what diseases can cause him to work too slowly, how bradyarrhythmias develop, and what treatments are available.

Bradyarrhythmiasand conduction disturbances are a similar group of disorders in which the heart beats too slowly, but the mechanism is slightly different. In the case of bradycardia and bradyarrhythmias, the production of impulses in the sinus node is too slow, which may be due to damage to the sinus, heart disease or systemic diseases.

Diagnostics of bradyarrhythmias should also take into account non-cardiac causes. If reversible causes of too slow heart rate are excluded, in many cases it is necessary to implant a pacemaker.

Bradyarrhythmia - causes

Too slow heartbeat, i.e. bradycardia, is a symptom that may occur in the course of many diseases. The immediate cause is a decreased frequency of stimulus production in the sinus node - this can result in sinus bradycardia or the formation of so-called escape rhythms. The reasons for a too slow heartbeat or a temporary complete stop of its heartbeat can be, among others:

  • thyroid disease
  • electrolyte disturbances - incorrect levels of calcium, potassium and sodium in the plasma
  • neurological diseases
  • previous cardiac surgeries
  • hypoglycemia
  • hypothermia
  • connective tissue diseases
  • drugs, e.g. beta-blockers used in arterial hypertension

Cardiological diseases include: ischemic heart disease, myocarditis, congenital heart defects, atrioventricular blocks.

It is very often the so-called sick sinus syndrome, i.e. a disease involving damage to this structure, in which it becomes insufficient - it produces too little stimulation.

Another possibility is so-called chronotropic failure, which also results from disease of the sinus node itself, and involves the heart not speeding up sufficiently during exercise.

The group of bradyarrhythmias also includes the so-called rhythmssubstitutes that we deal with in the case of damage to the sinus node. In such cases, impulses are generated from lower centers - e.g. the atrioventricular node, thus ensuring minimal heart rate, but it beats slower than in normal conditions.

Bradyarrhythmia - symptoms

Bradycardia is a condition in which the heart beats too slowly, i.e. below 60 beats per minute. Sometimes it does not cause any symptoms, and their occurrence and severity depend on many factors: age, physical activity or other diseases, especially cardiological ones.

The most common ailments in people with bradyarrhythmias are:

  • easy fatigue,
  • dizziness,
  • fainting,
  • palpitations,
  • less fainting.

In exceptional situations, there are less specific symptoms:

  • concentration disorders,
  • imbalance,
  • blurred vision,
  • shortness of breath.

If a bradyarrhythmia is so severe that it causes a temporary cardiac arrest, so-called MAS syndromes (loss of consciousness, breathing difficulties, seizures) develop.

Bradyarrhythmia - diagnosis

In diagnostics, a carefully collected history is very important: about the situations in which the loss of consciousness takes place, how long it lasts, what symptoms accompany it, other diseases and the medications used are also of great importance.

The diagnosis of bardyarrhythmia includes a series of tests:

  • electrocardiogram (EKG)
  • Holter EKG test - 24-hour ECG monitoring

Event recorders, i.e. devices recording the heart's electrical activity in times of worse well-being, and implantable recorders are used less frequently.

In special cases, it may be necessary to perform an invasive electrophysiological test.

All these tests are aimed at detecting arrhythmias, then it is necessary to look for its causes, which can be helped by a series of tests:

  • stress test
  • echocardiography
  • coronary angiography
  • Chest X-ray
  • laboratory tests: electrolytes, thyroid hormones, blood count

If other causes are excluded, conduction in the conduction system is appropriate, a sick sinus node syndrome is diagnosed.

In the case of impulse conduction disturbances, it is referred to as atrioventricular blocks.

Bradyarrhythmia - treatment

Pharmacological treatment of bradycardia is very difficult and basically impossible,because there are no drugs that stimulate the work of the heart that can be used orally for a long time.

First of all, it is necessary to exclude reversible causes - electrolyte disturbances, thyroid diseases or the influence of medications used.

Sometimes you can stop taking certain medications that can slow the heart rate - so-called beta-blockers, used in high blood pressure, ischemic heart disease or heart failure.

If the cardiological cause of the symptoms is confirmed, and discontinuation of these drugs does not reduce the severity of the bradyarrhythmia, pacemaker implantation is necessary.

These devices, however, are reserved for patients who have proven to have specific symptoms related to bradycardia: fainting, dizziness, or a few seconds' breaks in their work.

The implanted pacemaker controls the heart function and, if necessary, stimulates it to work, it is a permanent and effective treatment of bradycardia.

Cardiac arrhythmias: causes and symptoms

Cardiac arrhythmia - symptoms, effects, diagnosis, treatment

Supraventricular arrhythmia: causes, symptoms, types, treatment

How does the conductive system work?

The conductive system is the structure responsible for the so-called automatism of the heart - a process not found in other organs of the human body. It involves the heart's own stimulation to work by generating electrical impulses and then conducting them.

In the first place, the stimulus is produced in the sinus node, this is due to the slowly occurring depolarization in its cells. When a certain value of the electric potential is exceeded, an impulse is created which then propagates through the atria, stimulating them to contract.

Then the stimulus is conducted through the atrioventricular node - between the atria and ventricles, then the bundle branches of His and Purkinje fibers. This way the impulse reaches the ventricles, which results in their electrical activation and contraction.

Such action of the conductive stimulus system in terms of stimulating and conducting stimuli ensures adequate stimulation of the heart, and thus its proper work and maximum effective contraction.

Disturbances in these processes can cause diseases - including bradyarrhythmias. Depending on the site of damage to the conductive system, these are: sinus node dysfunction, atrioventricular blocks and intraventricular blocks.

About the authorBow. Maciej GrymuzaA graduate of the Faculty of Medicine at the Medical University of K. Marcinkowski in Poznań.He graduated from university with an over good result. Currently, he is a doctor in the field of cardiology and a doctoral student. He is particularly interested in invasive cardiology and implantable devices (stimulators).

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Category:

Cardiology