АВТОМАТИЯ СЕРДЦА: ФИЗИОЛОГИЧЕСКИЕ МЕХАНИЗМЫ, РЕГУЛЯЦИЯ И КЛИНИЧЕСКОЕ ЗНАЧЕНИЕ.

The automatization of the heart is its fundamental ability to independently generate electrical impulses that initiate heart contractions, without external stimulation from the nervous system. This review is devoted to a comprehensive review of this phenomenon. The main driver of the rhythm is normally the sinoatrial (CA) node, whose cells have unique electrophysiological properties, in particular, the ability to slow spontaneous diastolic depolarization (phase 4 of the action potential). This process is based on the complex dynamics of ion currents, including the "funny" current (If), calcium currents (ICa,T, ICa,L) and potassium currents (IK). The review examines in detail the ionic mechanisms of pacemaker activity, the hierarchy of pacemakers (CA node, atrioventricular node, Gis-Purkinje system) and the phenomenon of suppression of the underlying centers of automatism (overdrive suppression). The mechanisms of regulation of heart rate by the autonomic nervous system (sympathetic and parasympathetic), humoral factors (adrenaline, thyroid hormones) and other influences (temperature, ion balance, hypoxia) are highlighted. The clinical significance of automation is discussed, including pathological conditions such as CA node dysfunction (sinus node weakness syndrome), ectopic foci of automatism, atrial and ventricular arrhythmias associated with abnormal automation, as well as approaches to their diagnosis (ECG) and treatment (antiarrhythmic drugs, artificial pacemakers). In conclusion, modern research directions in this field are considered, including the study of the genetic basis of automatism disorders and the development of biological rhythm drivers.