Computerized tomography image correlation of His bundle/deep septal pacing location and outcomes: an analysis from the Canberra HIs bundle/deep septal Pacing Study (CHIPS)

Sreevilasam P Abhilash,Rajeev Kumar Pathak,Simon Stolcman,Prashanthan Sanders,Walter P Abhayaratna,Aakash Mahajan,Dennis H Lau,Ren Tan,Dong Seok Yi,Deep Chandh Raja,Moyazur Rahman

doi:10.1007/s10840-022-01133-z

Abstract

BackgroundLocalisation of the conduction system under fluoroscopy is not easy and the ideal location of the pacing leads in physiological pacing is still being debated.ObjectiveThe primary aim was to assess the lead locations using cardiac CT scan. Secondary aims were clinical outcomes including success and safety of the procedure and lead performance.MethodsOf the 100 consecutive patients who received physiological pacing, 34 patients underwent follow-up cardiac CT scan. The four different types of pacing were identified as His bundle (HBP), para-Hisian, left bundle branch (LBBP), and deep septal pacing.ResultsMost patients had successful HBP via the right atrium (RA) (87.5%) as compared to the right ventricle (RV) (12.5%). Lower thresholds were observed when leads were placed within 2 mm of the junction of the membranous and muscular ventricular septum. Unlike HBP, LBBP was possible at a wide region of the septum and selective capture of individual fascicles was feasible. LBBP showed deeper penetration of leads into the septum, as compared to deep septal pacing (70% vs. 45%). Approximately, 80% of patients did not have an intra-ventricular portion of the membranous septum.ConclusionsThe anterior part of the atrio-ventricular (AV) septum at the junction between the membranous and muscular septum via RA appeared to be the best target to successfully pace His bundle. LBBP was possible at a wide region of the septum and selective capture of individual fascicle was feasible. Adequate depth of penetration of lead was very important to capture the left bundle.

Highlights

Conventional right ventricular pacing is known to cause ventricular dyssynchrony, heart failure, and increased mortality
The present study primarily aimed to look at the pacing lead locations at the follow-up cardiac computerised tomography (CT) scan and correlate with the conduction system capture on the 12-lead electrocardiograms (ECG)
In 3 patients, the CT scans had to be excluded from analysis due to lead artefacts or poor-quality images

Summary

Introduction

Conventional right ventricular pacing is known to cause ventricular dyssynchrony, heart failure, and increased mortality. By maintaining conduction through the normal His-Purkinje system, ‘physiological pacing’ prevents ventricular dyssynchrony and may prevent pacing-mediated cardiomyopathy [1]. His bundle pacing (HBP) was described initially as the. LBBP showed deeper penetration of leads into the septum, as compared to deep septal pacing (70% vs 45%). Conclusions The anterior part of the atrio-ventricular (AV) septum at the junction between the membranous and muscular septum via RA appeared to be the best target to successfully pace His bundle. Adequate depth of penetration of lead was very important to capture the left bundle

Methods

Discussion

Conclusion