His bundle pacing-is it the final frontier of physiological pacing ?-A single centre experience from the Indian sub-Continent.

BACKGROUND: Long term right ventricular pacing can have deleterious effects on left ventricular (LV) function. His bundle pacing (HBP), a novel procedure can probably circumvent this setback. We investigated if (1) HBP is associated with pacing induced LV dysfunction by using LV global longitudinal strain (GLS) and (2) intermediate term performance of the Select Secure (3830) lead in the His bundle location. This report is probably the first on HBP in the Indian population.

METHODS: 61 patients, with normal LV ejection fraction (EF) with a guideline based indication for permanent pacing underwent a HBP pacemaker implantation using the His Select Secure 3830 lead; with lead guided mapping for locating the His bundle. The patients underwent GLS assessment; evaluation of the His lead parameters - sensing, impedance and capture thresholds immediately after implantation and at 6 months in addition to the standard follow up.

RESULTS: At 6 month follow up, the average GLS did not show significant variation from baseline in patients requiring ventricular pacing more than 40% and was similar, irrespective of selective or non selective His bundle pacing. All the patients had stable pacemaker parameters - with little change in capture threshold, lead impedance or sensing of the His bundle lead - implying electrical and mechanical stability on intermediate term follow-up.

CONCLUSION: HBP is a feasible procedure in the hands of an experienced operator, with stable lead performance. It does not appear to be associated with pacing mediated left ventricular dysfunction at intermediate term follow up. It should probably become the default method of permanent pacing.