A single-centre experience of His bundle pacing without electrophysiological mapping system: implant success rate, safety, pacing characteristics and one-year follow up

Figures

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  Figure 1. ECG shows transition of non-selective His bundle (NSHB) pacing to selective His bundle pacing from the pacing system analyser strip at a sweep speed of 50 mm/s. The marker channel is in the middle of tracing, in which ‘AP’ indicates pacing at the His bundle region. The ECG tracing (lead II) is above the marker channel. The intracardiac electrogram is below the marker channel. The local electrogram (arrow) is discrete from the pacing stimulus compared with the preceding beat, suggesting selective His bundle pacing with loss of ventricular capture. The corresponding surface ECG QRS (arrow head) is narrower (120 ms) than the previous QRS complex (160 ms). Therefore, the NSHB capture threshold is 0.6 V at 1 ms.

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  Figure 2. ECG of the same patient in Fig. 1 shows a transition from selective His bundle (SHB) pacing to ventricular pacing based on the pacing analyser strip, which has a sweep speed of 50 mm/s. The marker channel is in the middle of the tracing in which ‘AP’ indicates pacing at the His bundle region. The ECG tracing (lead II) is above the marker channel. The intracardiac electrogram is below the marker channel. There is no discrete local electrogram (arrow) at pacing compared with the preceding beat, suggesting pure ventricular capture because of loss of SHB capture threshold. The corresponding surface ECG QRS (arrowhead) is wider (200 ms) than the previous QRS complex (120 ms). Therefore, the SHB capture threshold is 0.3 V at 1.0 ms. The RV capture threshold is <0.2 V at 1.0 ms.

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  Figure 3. Graph shows reduced fluoroscopy time and radiation between two timeframes. DAP: dose area product

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  Figure 4. Graph shows improvement in procedure time and mean number of acute lead displacement between two timeframes.