Three-dimensional reconstruction of the structure of the cardiac layer, compiled from confocal images (20 confocal slices). (A) Sample received by transplant (transferred on 18th day, stained on 50th day). The top pictures display DAPI and alpha-actinin separately in depth-coding, showing the exact coordinate along the vertical axis. The lower figures show a qualitative picture of the relative positions of these two markers. Figure (B). Presents the structure of the control sample (stained on 50th day). (C) Comparison of the structure and distribution of conductive cells of control samples and transferred ones (amplitude charts, sample size - 15 mm). A qualitative comparison is presented in the upper figures, where black is the non-conductive zone of the sample and white is the conductive zone. The color is determined in accordance with the maximum amplitude of the intensity fluctuations in the dependence of the optical mapping experiment. A numerical comparison of data is presented in the diagram (D). **p-value <0.001 (n = 10, m = 11).