[Indications for His bundle and left bundle branch pacing].

His bundle pacing (HBP) allows ventricular excitation through the entire cardiac conduction system, resulting in a better synchronicity and efficacy of contraction compared to myocardial pacing. Due to better, dedicated implantation tools and exact practical implantation recommendations, HBP has developed into a form of stimulation that can be successfully applied with reasonable time and effort in >90% of patients. The rate of lead dislodgement and threshold increase is similar to conventional pacemaker systems. Despite a rather weak data base and a paucity of randomized trials, HBS represents an alternative to conventional right or biventricular pacing in the following conditions: (1) high-degree atrioventricular (AV) block with expected ventricular pacing >20% of the time, (2) AV block 1st degree with long PQ (alone or in combination with intermittent 2nd to 3rd degree AV block or sick sinus syndrome), (3) AV node ablation due to refractory atrial fibrillation, and (4) upgrade in pacing-induced cardiomyopathy. Moreover, HBP may be useful in context with cardiac resynchronization therapy (CRT). Left bundle branch block below the level of His represents a limitation of HBP. Therefore, more recently left bundle branch pacing (LBBP) has been introduced to correct left bundle branch block. LBBP seems to be possible in a wider anatomic area and may be easier to implant. However, LBBP requires active screw-in of the lead deep into the ventricular septum. Experience with this new technique is limited, particularly regarding long-term performance.