[Rhythmogenesis in the sinoatrial unit of the heart].

The most significant experimental data about the formation of a uniform rhythm of the sinoatrial unit of the heart for both the intact sinoatrial unit of the heart and cardiomyocytes in cellular structures are presented. The basic mathematical models for studying the processes of synchronization in the sinoatrial unit of the heart are described, including equations of Noble, Bonhoffer, and van der Pol and modified axiomatic models. The basic results obtained using the mathematical models are presented. The major reasons influencing the formation of a uniform rhythm were revealed: the form of a potential pacemaker in the phase of slow diastolic depolarization, its porosity, the force of connection between pacemaker and electric capacity of pacemakers. A study of rhythmogenisis on the basis of the modified axiomatic model was carrud out. The method allows one to calculate the uniform rhythm of the sinoatrial unit of the heart in view of the mutual influence of pacemaker cells, including the force of connection, electric capacity of cells, their possible clusterization. It was shown that generally the uniform rhythm of the sinoatrial unit of the heart is formed on an intermediate level of all pacemaker cells.