Limitations
This was a UHF-ECG analysis of ventricular depolarization patterns from different types of ventricular pacing during implant procedures. The data acquisition for UHF-ECG analysis was performed immediately after lead fixation in a predefined location and confirmation of ventricular capture. It is possible that during lead fixation in the para-hisian area, damage to the conductive tissue occurred in some patients, which could have influenced the paced ventricular depolarization pattern. Data were not compared to any other invasive or noninvasive electrocardiographic methods, and no hemodynamic or echocardiographic measurement of mechanical dyssynchrony was performed.