Instillation of TiO
-NPs and in vivo recordings of cardiac electrical performance. A. Time-scale (hours) of the experimental protocol. B. Representative EGs recorded from an 8×8 epicardial electrode array. Each waveform of the grid represents the time-course of extracellular potential at the corresponding position. The scheme on the right hand side explains the EG parameters, as measured from their root mean square (RMS)-derived signals. Magenta thin trace represents the first time derivative, whose minimum value is taken as a marker of the end of the QT interval C. Representative activation time maps (isochrones, ms) from Vehicle (left) and NPR (right), showing differences in longitudinal (red arrows) and transverse (blue arrows) propagation.