Introduction. The treatment of congenital complete AV block (CCAVB) is burdened by RV-associated ventricular dysfunction at long-term in a subgroup of patients. Methods and Results. Two CCAVB adolescents with mild systolic dysfunction associated to VVIR pacing reached elective pacemaker replacement after 10±1 years. They were upgraded to physiologic stimulation by restoring AV synchrony and ventricular activation via His bundle pacing (HBP). At 9-months follow-up both had reverse left ventricular (LV) remodeling: LV end-diastolic volume index decreased from 89±4 to 70±7 ml/m2, LV end-systolic volume index decreased from 49±1 to 32 ml/m2, LVEF increased from 43±1% to 53±4%. Conclusions. HBP can improve LV function in CCAVB adolescents. It should be considered in the setting of LV dysfunction associated to RV pacing, and should be explored as first-choice treatment from late childhood onward.