Left bundle branch pacing with and without anodal capture: impact on ventricular activation pattern and acute haemodynamics

Figures

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  Figure 1. Activation during non-selective left bundle branch capture without anodal capture. Activation starts with local myocardial capture. The RV activates from base to apex (i.e. not consistent with right bundle activation), and the latest activated area is the basal free wall (which appears to activate from a wavefront propagating from the posterior wall). The left ventricle activates in a physiological fashion from apex to base. LAD, left anterior descending artery; LV, left ventricular; RV, right ventricular.

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  Figure 2. Non-selective left bundle branch capture with anodal capture. The RV is activated early, compared with capture without anodal capture. Right ventriclar activation occurs from base to apex (i.e. different to intrinsic activation via the right bundle). Activation of the basal lateral wall of the RV is advanced compared with LBBP without anodal capture. Right ventriclar activation appears to occur via a single wavefront (rather than the two wavefronts observed during capture without anodal caputure). The left ventricle activates in a physiological fashion from apex to base. LAD, left anterior descending artery; LV, left ventricular; RV, right ventricular.

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  Figure 3. Comparison of activation times with and without anodal capture. (Left) QRS duration (12-lead ECG) produced by non-selective LBBP without and with anodal capture, there was a modest reduction in QRS duration associated with anodal capture. (Middle) TVAT (measured with multi-electrode mapping) with and without anodal capture, there was a modest reduction in TVAT with anodal capture. (Right) LVAT (measured with multi-electrode mapping) with and without anodal capture, there was no difference in LVAT between the two configurations. ECG, electrocardiogram; LVAT, left ventricular activation time; NSLBBP, non-selective left bundle branch pacing; TVAT, total ventricular activation time.

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  Figure 4. Comparison of activation time between non-selective LBBP without anodal capture and LBBP with AV delay programmed to allow fusion with intrinsic right bundle activation. (Left) TVAT (measured with multi-electrode mapping) with and without fusion with intrinsic right bundle conduction, there was a modest reduction in TVAT with fusion with right bundle branch conduction. (Right) LVAT with and without fusion with intrinsic right bundle conduction, there was no difference in LVAT between the two configurations. LVAT, left ventricular activation time; NSLBBP, non-selective left bundle branch pacing; RBB, right bundle branch; TVAT, total ventricular activation time.

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  Figure 5. Acute haemodynamic comparison of LBBP with and without anodal capture. We found no difference in acute haemodynamic response during left bundle pacing with and without anodal capture. NSLBBP, non-selective left bundle branch pacing.

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  Figure 6. Pacing threshold for non-selective LBBP with and without anodal capture. Achieving anodal capture in addition to left bundle area capture required significantly higher pacing outputs. NSLBBP, non-selective left bundle branch pacing.