hiPSC-CMs transfer experiment. (A) Design of the experiment, transfer procedure. (B) Immunocytochemistry of single cardiomyocytes after disaggregation. (C) Optical recording of the action potential of transferred cardiomyocytes with frequency of 130 Hz. The black curve shows the control action potential. Red is the action potential of cells after transfer. The numerical changes in APD80 under the action of isoprenaline and E4031 are shown in Figures (D,E), respectively (n = 3 is the number of different tissue samples). (F) shows activation maps of the hiPSC-CMs syncytium excitation wave for the control sample (above) and the sample obtained by transfer (below).