Atrial cardiac pacemaker

Схематическое изображение проводящей системы сердца (выделено синим цветом):

(1) синусо-предсердный узел,

(2) предсердно-желудочковый узел

In pathological conditions, the role of the pacemaker can be performed by other areas of the heart, rather than with sinus rhythm driver. Muscle cells of the heart generate impulses by themselves, without any external influences (automata). The sinus-atrial node suppresses all lower sections of the conducting system by more frequent pulses, but if it is damaged by the pacemaker, the atrioventricular node, which generates pulses with a frequency of 40-50 per minute, can become a rhythm driver.

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