Six transition patterns and seven capture types in different left bundle branch bipolar pacing configurations

Area of Science:

• Electrophysiology
• Cardiovascular Pacing
• Cardiac Electrophysiology

Background:

• Left bundle branch pacing (LBBP) is an emerging technique for physiological pacing.
• Optimizing LBBP requires understanding different pacing configurations and their capture characteristics.
• Selective LBB capture is crucial for effective LBBP.

Purpose of the Study:

• To explore transition patterns and capture types during bipolar pacing for selective LBB capture.
• To evaluate the efficacy of different bipolar pacing configurations.
• To identify optimal pacing strategies for physiological pacing.

Main Methods:

• 67 patients underwent unipolar and bipolar pacing tests using selective LBB capture.
• Continuous pacing and recording techniques were employed.
• Electrophysiological characteristics of "Tip-Ring+" and "Ring-Tip+" configurations were analyzed.

Main Results:

• Six transition patterns and seven capture types were identified.
• "Ring-Tip+" bipolar pacing demonstrated a significantly lower threshold (1.57 vs. 2.84 V at 0.5 ms) for simultaneous LBB and ventricular septum capture compared to "Tip-Ring+".
• "Ring-Tip+" was the only configuration to achieve "LBBP + right ventricular septum pacing (RVSP)" capture.

Conclusions:

• "Ring-Tip+" bipolar pacing provides a lower threshold for simultaneous LBB and ventricular septum capture.
• The "LBBP + RVSP" capture type achieved with "Ring-Tip+" represents a potentially advantageous physiological pacing configuration.
• Further investigation and application of "Ring-Tip+" pacing are warranted.