Atrioventricular block

The atrioventricular block (AVB) is one of dangerous disturbances of conductivity of heart, consisting in a delay of the impulse passing through the atrioventricular node which is between an auricle and ventricles. AVB to 20-40 beats per minute, a loss of consciousness and the phenomena of heart failure is followed by sudden sharp delay of a cordial rhythm. According to the statistics WHO, 17% of sudden death because of sudden heart failure, come from AVB.

AVB is classified by 3 degrees:

The first degree — clinically is not shown, characterized by a small delay of passing of impulses and can be revealed only when carrying out an electrocardiography. On this degree treatment is not carried out, but in order that there was no development into higher degrees, observance of the preventive measures consisting in careful use of antiarrhytmic drugs, etc. cardiacs is required.

The second degree is characterized by the fact that the part of electric impulses does not pass to ventricles. There are interruptions in cardiac performance, a sudden loss of consciousness. Statement of the diagnosis requires an ECG.

The third degree is a total atrioventricular block, is characterized by complete cessation of passings of impulses to ventricles which sharply slow down reductions. The patient can be unconscious in a dangerous state which can lead to death.

Since the second degree, operational treatment of an atrioventricular block and installation of an electrocardiostimulator is required.

Symptoms of an atrioventricular block

Атриовентрикулярная блокадаDisturbances of passability of impulses can be caused by organic diseases, such as a myocardial infarction, a cardiomyopathy, coronary heart disease, heart diseases, myocardites, etc. which can lead to defeat of atrioventricular connection, the weakest link of the carrying-out cordial system. Also, reception of some medicines, from group of β-blockers, cardiac glycosides, antiarrhytmic means, etc., and also, intensive sports activities can be the reasons.

At the first stage noticeable symptoms of an atrioventricular block are absent. At manifestations of disturbance of conductivity of heart, the patient complains of the general weakness, fast fatigue, dizziness, an asthma. At bradycardia, the patient has heat inflow, blackout, feeling of a close loss of consciousness, lowering of arterial pressure.

Diagnosis of an atrioventricular block

At an assessment of the anamnesis existence postponed in the past of a myocardial infarction and other cardiac pathologies, the drug intake fact which break atrioventricular conductivity becomes clear. Auscultation of a cordial rhythm is carried out, the frequency of a pulsation of cervical veins in comparison with carotid and beam arteries is defined.

Also diagnosis of an atrioventricular block by an ECG research method with daily monitoring, for the purpose of an assessment of degree of bradycardia and blockade is carried out. Existence of communication with activity of the patient or drug intake is defined. Electrophysiologic research of heart (EFI) is conducted to define indications to implantation of a pacemaker, etc. If necessary, additional laboratory researches on existence of associated diseases are conducted.

Treatment of an atrioventricular block

At 1 degree treatment is not required, treatment 2 and 3 degrees of AVB consists in implantation of a constant electrocardiostimulator which will recover and will support normal rate of cordial reductions. After that, the illness is eliminated. In critical states use a temporary electrocardiostimulator.

Section: Cardiology