Characteristics of paced waveforms and current of injury prior to septal perforation during left bundle branch area pacing

Figures

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  Figure 1. Paced intra-cardiac waveforms with progression of the lead from the left subendocardium to microperforation and macroperforation (illustrated on the top of the panel). Note the fall in paced COI amplitude, which approaches, but does not drop to <5 mV, with appearance of a deep and broad Q-wave before macroperforation and loss of capture (last two spikes) followed by a sensed beat (with a deep Q-wave and COI amplitude <5 mV). In the bottom panel, the paced COI amplitudes during LBBAP implantation leading to macroperforation in all analysed patients can be appreciated, at four timepoints: septal entry, maximum amplitude obtained during lead advancement, paced COI amplitudes at 10 beats prior to perforation, and the last paced beat before perforation. The stars, coloured according to the corresponding line, indicate the amplitude of paced COI when the first Q wave occurred. Values are presented as median (Quartile 1–Quartile 3). COI, current of injury; CSP-UF, conduction system pacing unfiltered channel (0.5–500 Hz); LBBAP, left bundle branch area pacing.