Left bundle branch pacing guided by premature ventricular complexes during implant

Figures

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  Figure 1. A: Left bundle branch pacing (LBBP) for nonischemic cardiomyopathy (NICM) with left bundle branch block (LBBB). (i) Premature ventricular contractions (PVCs) with changing morphology from QS to qR pattern (PVC1) in lead V1 noted during rapid rotation. (ii) Left bundle branch (LBB) paced QRS mimicked PVC1 with duration of 124 ms and peak left ventricular activation time (pLVAT) of 78ms. (iii) Final 12-lead electrocardiography (ECG) after correcting right bundle branch delay by AV interval optimization (QRS duration 108 ms). B: LBBP for NICM with LBBB. (i) PVCs with changing morphology from QS to rSR pattern (PVC2) in lead V1 noted during rapid rotation. (ii) LBB paced QRS morphology mimicked VES1 with duration of 122 ms and pLVAT of 65 ms. (iii) Nonselective (first 2 beats) to selective LBB capture (last 2 beats) at near threshold output. (iv) Final 12-lead ECG after RBB delay correction by optimizing the AV delay (QRS duration 98 ms). His d = distal His bundle electrogram; LBB = pacing lead electrogram bipolar; LBU = pacing lead electrogram unipolar.

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  Figure 2. Left bundle branch pacing (LBBP) and atrioventricular junction ablation. A: Premature ventricular contractions (PVC) with changing morphology during lead rotation. B: Left bundle branch (LBB) paced QRS mimicked PVC3 with duration of 124 ms and peak left ventricular activation time 65 ms. C: Pacing lead electrogram (LBB) showing sharp LBB potentials (LB Po) preceding the local ventricular electrogram. D: Nonselective (first 2 beats) to selective (last 2 beats) capture of LBB. His d = distal His bundle electrogram; His p = proximal His bundle electrogram; His Po = His bundle potential; LBB = pacing lead electrogram bipolar; LBU = pacing lead electrogram unipolar; RVA = right ventricular electrogram.

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  Figure 3. Left bundle branch pacing for complete heart block. A: Premature ventricular contractions (PVCs) during left bundle branch (LBB) lead placement. B: Paced QRS morphology mimicked PVC4 with duration of 114 ms and peak left ventricular activation time of 70 ms. C: Pacing lead electrogram showing sharp LBB potential (LB Po) preceding the local ventricular electrogram. D: Final 12-lead electrogram (ECG) after right bundle branch delay correction by anodal capture (QRS duration 100 ms). His d = distal His bundle electrogram; His p = proximal His bundle electrogram; His Po = His bundle potential; LBB = pacing lead electrogram bipolar; LBU = pacing lead electrogram unipolar; RVA = right ventricular electrogram.