Decoding left bundle branch block: insights into the future of his-purkinje conduction system pacing

His bundle pacing (HBP) has the unique ability to deliver and replicate normal infra-nodal conduction (1). It has therefore been used in variety of pacing indications including pacing for bradycardia pacing and in patients undergoing atrioventricular (AV) node ablation (2,3). Furthermore, in some patients who have underlying bundle branch block (BBB), HBP has been able to narrow the QRS and reverse the conduction abnormality (4). This has enabled HBP to be studied in patients requiring biventricular pacing (BVP) for cardiac resynchronisation therapy (CRT) including those with failed left ventricular (coronary venous) lead placements or those who have not responded to BVP (5,6). Outcomes in general, have been positive with significant success in this group albeit in small non-randomised studies.