Discussion
This UHF-ECG study describes in detail the time delays between the activation of ventricular segments during RV pacing and shows: (1) pacing of the basal interventricular septum with conductive system engagement produces the smallest ventricular dyssynchrony compared to other myocardial captures of the right ventricle and (2) pacing of RV septal inflow area results in less LV ventricular dyssynchrony than septal RVOT pacing, although no differences in QRSd were observed between them.