A Novel Pacing Strategy With Low and Stable Output: Pacing the Left Bundle Branch Immediately Beyond the Conduction Block.

This report demonstrates the feasibility of pacing the left bundle branch (LBB) immediately beyond the conduction block to functionally restore the impaired His-Purkinje conduction system in a patient with heart failure and left bundle branch block (LBBB). The pacing required only a low pacing output (0.5 volts/0.5 ms) to correct the LBBB with accompanying right BBB on the electrocardiogram. Over 1-year of follow-up, the patient had a significant improvement in clinical outcome and echocardiographic measurements. The case shows a novel pacing strategy for patients with BBB that affects many patients with heart failure.