Heart block is a heart rhythm disturbance that is associated with slowing or interruption of an electrical pulse to the cardiac conduction system.
In place of the blockade can be divided into:
atrial (sinoatrial), when the slowing of nerve impulses occurs at the level of atrial muscle atrio-ventricular - a violation of the atrioventricular node intraventricular - at the bundle of His and his legs.
Atrial blockade occur when conduction disturbance in the conduction system of atrial muscle. Against the background of normal rhythm is to reduce loss of myocardium and there is a pause equal to approximately two cuts. At a constant form of a blockade it is difficult to distinguish from the merely slow the heart rate - bradycardia. This type of blockade is possible in healthy subjects and in patients with coronary heart disease, inflammatory diseases of the heart muscle, poisoning, overdose of certain drugs (cardiac glycosides, quinidine, verapamil). In severe degree of blockade of the patient may be fainting and even seizures loss of consciousness with convulsions. Sometimes a block can move to another violation of the rhythm - atrial or atrial flutter.
Treatment of atrial blockades in good health the patient is not required. Sometimes appointed bellataminal, Belloidum, ephedrine. If the patient has bouts of unconsciousness or heart rate less than 40 per minute is implantation of an artificial pacemaker.
Violations of the atrio-ventricular conduction (atrioventricular block) occurs in violation of the electrical impulse from the atria into the ventricles at the atrioventricular node. Such conduction disturbances occur in many diseases of the heart, most often in rheumatic lesions, coronary heart disease, myocardial infarction, cardiosclerosis, congenital heart defects, cardiomyopathy. Occasionally, a rhythm disturbance occurs in healthy people have trained pilots and kosmonavtov.Predserdno-ventricular block is of three degrees:
I degree. In this case all the impulses from the atria reach the ventricles, but holding them slowed down. Diagnosed with a blockade of the change of teeth on the electrocardiogram. Treatment of atrioventricular block first degree depends on the underlying disease, and sometimes requires a pacemaker.
Grade II. In the second degree atrioventricular block, not all impulses from the atria to the ventricles are carried out and drop some ventricular contractions. On the electrocardiogram are first signs of a slowdown of the complexes or normal, and then recorded only prong that corresponds to the reduction of atrial and ventricular reduction is absent. Could fall every fifth, fourth, third, etc. reduction. Blockages that occur with no slowing of the previous can go to the full atrioventikulyarnuyu blockade. Treatment of second degree of the blockade also significantly depends on the underlying disease. Sometimes the use of atropine, izadrin. If the heart rate decreased significantly applied constant electrical stimulation of the heart - a pacemaker.
Grade III. Complete atrioventricular block. At the same time an electrical impulse from the atria to the ventricles is not done at all, and the atria and ventricles in the right rhythm, but independently of each other. The frequency of atrial contractions are usually high, and the ventricles at a slow pace of 30-50 per minute. In this type of blockade of the patient may experience bouts of Morgagni-Adams-Stokes equations, when the mind is disturbed, may be convulsions, cyanosis (blueness) of the person, the pain in the heart. Pulse and heart rate, respectively, at this point are not available. Seizures occur because of a temporary cessation of circulation. The prognosis for such a degree atrioventricular block serious. Patients unable to work, they develop heart failure. In attacks of Morgagni-Adams-Stokes equations may have to do chest compressions and artificial ventilation legkih.Vozniknovenie conduct such attacks, or at least their initial symptoms (attacks of dizziness, weakness) is an absolute indication for continuous electrical stimulation.
Implantation of a pacemaker is needed and those patients whose heart rate is less than 50 beats per minute even when they have no complaints. Patients with implanted pacemakers should be kept under medical supervision.
Violations of the ventricular conduction occur mainly in bundle branch block on which the electrical impulse is conducted in the ventricle, and his legs - left and right. To give the appearance of ventricular blocks ischemic heart disease, myocardial infarction, myocarditis, cardiomyopathy, infectious endocarditis, disturbances of electrolytes (potassium, calcium, chlorine) in the blood.
Sometimes there are inherent blockade of one of the bundle-branch block, right more often, or bundle-branch block branches. Congenital block usually does not affect the quality of life and do not lead to any disease of the heart. Ventricular block is usually easily diagnosed by electrocardiogram. They are typically looking complexes. By themselves, bundle branch block legs are not dangerous for the patient's life is determined by the value of their clinical progression and the possibility of transition to complete atrioventricular block, or they may serve as an indicator of the heart of a pathological process. Very rarely trifastsikulyarnaya blockade, when conducting an electric pulse is blocked on all branches, then it may be necessary in a constant pacemaker.