Abstract:
Background : Increasing interest in physiological pacing has
been countered with challenges such as accurate lead deployment and
increasing pacing thresholds with His-bundle pacing (HBP). More
recently, left bundle branch area pacing (LBBAP) has emerged as an
alternative approach to physiologic pacing.
Objective : To compare procedural outcomes and pacing parameters
at follow-up during initial adoption of HBP and LBBAP at a single
center.
Methods : Retrospective review, from September 2016 to January
2020, identified the first 50 patients each who underwent successful HBP
or LBBAP. Pacing parameters were then assessed at first follow-up after
implantation and after approximately one year, evaluating for acceptable
pacing parameters defined as sensing R-wave amplitude >5
mV, threshold <2.5 V @ 0.5 ms and impedance between 400 and
1200 Ohms.
Results : The HBP group was younger with lower ejection fraction
compared to LBBP (73.2±15.3 vs 78.2±9.2 years, p=0.047; 51.0±15.9% vs
57.0±13.1%, p = 0.044). Post-procedural QRS widths were similarly
narrow (119.8±21.2 vs. 116.7±15.2ms; p = 0.443) in both groups.
Significantly fewer patients with HBP met the outcome for acceptable
pacing parameters at initial follow-up (56.0% vs 96.4%, p = 0.001) and
most recent follow-up (60.7% vs 94.9%, p = <0.001; at
399±259 vs. 228±124 days, p = <0.001). More HBP patients
required lead revision due to early battery depletion (0 vs 13.3%, at
an average of 664 days).
Conclusion : During initial adoption, as compared with LBBAP,
HBP is associated with a significantly higher frequency of unacceptable
pacing parameters, energy consumption, and lead revisions.