Left ventricular work asymmetry indicated by septal and lateral work (upper panels) and by the lateral wall to septal work difference (lower panels). Left ventricular work is evenly distributed at baseline in all patients. Pacing induced a significant lateral-to-septal work difference in RVP patients. LBBP, left bundle branch pacing; LW-SW, lateral-to-septal; RVP, right ventricular pacing. *P < 0.01 vs. LBBP; ^†P < 0.05 vs. baseline.