Clinical realization of anatomical and physiological properties of the sinoatrial node

Diseases of the sinoatrial node (SАN) are characterized by its inability to perform the function of the dominant pacemaker. This review presents data from recent studies of the anatomy and physiology of the SАN, which demonstrate the presence of structural and functional heterogeneity of the SAN and its components, describes the structure and function of the conducting intra-nodal pathways, the “novel paranodal area”, and also discusses the phenomenon of a shift in the site of excitation generation and the presence of a “non-firing mode” of cardiomyocytes. The authors critically discussed the genetic mechanisms of the development of sick sinus node syndrome (SSS), justified a multidisciplinary approach and further anatomical, morphological and physiological studies that play a fundamental role in the development of therapy and diagnosis of related diseases.