Parasystole
Description:
The parasystole — a special kind of ectopic arrhythmias, is characterized by existence of the geterotopny center which functions irrespective of the main pacemaker. Some authors carry a parasystole to the combined arrhythmias, proceeding from features of a pathogeny.
It is clinically shown in the form of extrasystoles or ectopic tachycardia (paroxysmal or not paroxysmal).
Parasystole symptoms:
1. Independence of ectopic complexes of the main rhythm. It is shown by inconstancy of an extrasystolic interval. (However if the parasystolic rhythm is dominating, this interval can be constant.)
2. Constancy of the shortest interectopic interval or existence of the common temporary divisor in distances between extrasystoles. Fluctuation of duration of interectopic intervals is usually not exceeded by 130 ms.
3. Existence of drain reductions (fusion beats) which are formed at simultaneous emergence of impulses of the main and ectopic pacemakers. At the same time various sites of a myocardium are excited from different sources of a rhythm.
Ventricular parasystole (ECG)
Parasystole reasons:
The parasystolic center generates impulses in a certain rhythm which fluctuations are insignificant. Impulses from the parasystolic center, finding a myocardium out of a refractory phase, cause its excitement and reduction.
The parasystolic center is protected from penetration of impulses of the basic (usually sinus) rhythm by so-called blockade of an entrance. Blockade of an exit also is characteristic of this disturbance of a rhythm that interferes with distribution of ectopic impulses from the parasitolichesky center.
The parasystolic center can be localized in:
* auricles;
* atrioventricular connection;
* ventricles.
Treatment of the Parasystole:
Different types of antiaritmik are applied to treatment.
