Bilateral Bundle Branch Area Pacing to Achieve Physiological Conduction System Activation

BACKGROUND–Left bundle branch pacing (LBBP) is a technique for conduction system pacing, but it often results in right bundle branch block (RBBB) morphology on the electrocardiogram. This study was designed to assess simultaneous pacing of the left and right bundle branch areas to achieve more synchronous ventricular activation. METHODS–In symptomatic bradycardia patients, the distal electrode of a bipolar pacing lead was placed at the left bundle branch area via a trans-ventricular septal approach. This was used to pace the left bundle branch area, while the ring electrode was used to pace the right bundle branch area. Bilateral bundle branch area pacing (BBBP) was achieved by stimulating the cathode and anode in various pacing configurations. QRS duration, delayed right ventricular activation time (dRVAT), left ventricular activation time (LVAT) and inter-ventricular conduction delay were measured. Pacing stability and short-term safety were assessed at three-month follow-up. RESULTS–BBBP was successfully performed in 22 of 36 patients. Compared with LBBP, BBBP resulted in greater shortening of QRS duration (109.3±7.1 ms vs. 118.4±5.7 ms, P