Late dislodgement of left bundle branch pacing lead and failure of left ventricle capture management algorithm

Figures

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  Fig. 1. Left bundle branch capture. Threshold testing in bipolar mode demonstrates transition from anodal capture + nonselective left bundle branch pacing (LBBP) to nonselective LBBP and subsequent selective LBBP. Note the retrograde His (H) electrograms and prolongation of stimulus to His intervals from 70 ms during anodal capture to 90 ms with LV septal capture to 140 ms during selective LBB capture.

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  Fig. 2. Twelve lead ECG at baseline (A) and following left bundle branch pacing (B).

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  Fig. 3. Device interrogation and chest radiograph. A. Left ventricular (LV) pacing impedance and capture threshold trends from device interrogation in November 2021 is shown. While the pacing impedance remained stable, the capture threshold appeared to have increased from 1.25V in May 2021 to 1.75V on August 2021, following which no further daily measurements have been performed. B. Chest X-ray post device implant shows normal appearing leads with adequate slack on all 3 leads. C. CXR one year later, demonstrates dislodgement of the LBBP lead with no slack while the right ventricular and right atrial leads appear stable. While line in figures B and C were drawn on the LBBP lead to better visualize the lead.

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  Fig. 4. Device interrogation showing ventricular non-capture. Electrograms from the device on presentation are shown. Atrial sensed events are followed by biventricular (BV) pacing and ventricular fibrillation (TF) sensed events. Right ventricular (RV) lead was programmed to minimal output (0.5V @ 0.05 ms) to facilitate left ventricle (LV) only pacing. However, due to LV lead dislodgement, there is ventricular non-capture followed by native conduction with long delay and a sensed ventricular (TF, 260–270 ms) event that falls in the ventricular fibrillation (VF) zone. This pattern repeats itself resulting in 20/40 sensed events continuously falling in VF zone.