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.