Blocking L-Type Calcium Current Reduces Vulnerability to Re-Entry in Human iPSC-Derived Cardiomyocytes Tissue

Abstract

[EN] Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have proven to be crucial in pharmacological assessment. Nevertheless, their response to drugs when coupled forming a tissue is not fully understood. Thus, the aim of this study was to determine whether blocking L-type Ca+2 current (¿"#$) in a hiPSCCMs tissue could be considered as a potential antiarrhythmic procedure. To analyze the effects of ¿"#$ block, the maximum conductance of ¿"#$ (¿"#$) was decreased (block conditions) and compared to control. In both situations, control and block, the tissue was stimulated following a cross-field protocol to generate re-entries. A phase analysis was performed and specific parameters, such as re-entry frequency (¿'(()*'+), excitation wavelength, vulnerable window (VW), and cellular excitability, were evaluated. Induced re-entries, where ¿"#$ was reduced by 70% showed a 6.9% and a 47.83% decrease in ¿'(()*'+ and in the width of the VW, respectively. Our results suggest that blocking calcium channels could be considered as an antiarrhythmic strategy in a hiPSC-CMs tissue.