A step forward toward conduction system pacing–based cardiac resynchronization therapy, albeit a small one

Starting from the very first clinical reports of the deep septal pacing technique by Mafi-Rad et al. and Huang et al., it became clear that the activation of the left ventricle (LV) during pacing near the left conduction system (the method known as left bundle branch area pacing – LBBAP) results in paced QRS that, in contrast to the conventional right ventricular pacing technique, has none of the features of left bundle branch block.1;2 On the contrary, the reported LBBAP paced QRS complexes showed rapid activation over the LV and demonstrates right bundle branch block pattern.