Abstract and Introduction
Abstract
Aims: This study aims to determine procedural characteristics, acute success rates, and medium-term outcomes of consecutive patients undergoing His bundle pacing (HBP); and learning curves of experienced electrophysiologists adopting HBP.
Methods and Results: Consecutive HBP patients at three hospitals were recruited. Clinical characteristics, acute procedural details, and medium-term outcomes were extracted from electronic medical records. Two hundred and thirty-three patients [mean age 74.6 ± 10.1 years, 48% female, 68% narrow QRS, 71% normal left ventricular ejection fraction (LVEF), 55.8% atrioventricular block] underwent HBP. Acute procedural success was 81.1% (mean procedural and fluoroscopic times of 105.5 ± 36.5 and 13.8 ± 9.3 min). Broad QRS was associated with lower HBP success (odds ratio 0.39, P = 0.02). Fluoroscopic and procedural times decreased and plateaued after 30–40 cases per operator. Implant HBP threshold was 1.3 ± 0.7 V at 1.0 ± 0.2 ms and R wave was 5.0 ± 3.9 mV. During follow-up, loss of HBP occurred in a further 12.4% and 11.3% of patients experienced a ≥1 V increase in HBP threshold. Five (2.6%) patients required HBP revision for pacing difficulties. About 8.6% of patients had a >50% decrease in R wave but lead revision for sensing issues was not necessary. On an intention to treat basis, 56.7% of patients in whom HBP was attempted had persisting HBP capture and thresholds of <2 V.
Conclusion: Physicians adopting HBP should be cognizant of the learning curve and preferentially select non-dependent patients with normal QRS and LVEF, to minimize risk of lead revision. Further rises in HBP threshold may increase battery drain and need for reoperations, important considerations when choosing HBP for cardiac resynchronization therapy.
Introduction
Long term and high burden of right ventricular apical pacing (RVP) cause ventricular dyssynchrony and is associated with a higher incidence of atrial fibrillation (AF), pacing-induced cardiomyopathy, heart failure (HF), and mortality.[1–3] His bundle pacing (HBP) can reproduce physiological ventricular activation to mitigate the adverse effects of RV pacing.[4–6]
The feasibility of selectively His bundle capture using a fixed screw-in pacing lead and to reproduce intrinsic QRS in HF patients with AF was demonstrated by Deshmukh et al.[7] more than 2 decades ago. However, early attempts were technically challenging and required lengthy procedures. With greater clinical experience and technical refinement, procedural success, and pacing parameters improved. In an observational study, HBP was associated with a reduction in death, HF hospitalization, or need for upgrade to biventricular pacing (BVP) compared to RVP in patients requiring permanent pacemakers.[4] This led to an increased adoption of HBP globally by electrophysiologists already experienced in pacing. In this study, we aim to determine procedural characteristics, clinical outcomes, learning curves, and clinical predictors of successful HBP amongst early adopters of HBP in Southeast Asia.
Europace. 2022;24(4):606-613. © 2022 Oxford University Press
Copyright 2007 European Heart Rhythm Association of the European Society of Cardiology (ESC). Published by Oxford University Press. All rights reserved.
