“…The benefits of biventricular pacing have also been reported in patients with CCAVB who developed congestive heart failure or DCM after RV pacing. 10, 15 Actually, strategies using LV single-site pacing or CRT have been increasingly applied worldwide, even in infants, with favorable results. However, there are currently no guidelines for selection of patients or timing for revision of pacing site or upgrading of pacing mode or devices.…”