Department of Biomedical Engineering, King's College London, London, UK.
BioTechMed-Graz, Graz, Austria.
J Cardiovasc Electrophysiol. 2023 Apr;34(4):984-993. doi: 10.1111/jce.15847. Epub 2023 Feb 14.
Conduction system pacing (CSP), in the form of His bundle pacing (HBP) or left bundle branch pacing (LBBP), is emerging as a valuable cardiac resynchronization therapy (CRT) delivery method. However, patient selection and therapy personalization for CSP delivery remain poorly characterized. We aim to compare pacing-induced electrical synchrony during CRT, HBP, LBBP, HBP with left ventricular (LV) epicardial lead (His-optimized CRT [HOT-CRT]), and LBBP with LV epicardial lead (LBBP-optimized CRT [LOT-CRT]) in patients with different conduction disease presentations using computational modeling.
We simulated ventricular activation on 24 four-chamber heart geometries, including His-Purkinje systems with proximal left bundle branch block (LBBB). We simulated septal scar, LV lateral wall scar, and mild and severe myocardium and LV His-Purkinje system conduction disease by decreasing the conduction velocity (CV) down to 70% and 35% of the healthy CV. Electrical synchrony was measured by the shortest interval to activate 90% of the ventricles (90% of biventricular activation time [BIVAT-90]).
Severe LV His-Purkinje conduction disease favored CRT (BIVAT-90: HBP 101.5 ± 7.8 ms vs. CRT 93.0 ± 8.9 ms, p < .05), with additional electrical synchrony induced by HOT-CRT (87.6 ± 6.7 ms, p < .05) and LOT-CRT (73.9 ± 7.6 ms, p < .05). Patients with slow myocardium CV benefit more from CSP compared to CRT (BIVAT-90: CRT 134.5 ± 24.1 ms; HBP 97.1 ± 9.9 ms, p < .01; LBBP: 101.5 ± 10.7 ms, p < .01). Septal but not lateral wall scar made CSP ineffective, while CRT was able to resynchronize the ventricles in the presence of septal scar (BIVAT-90: baseline 119.1 ± 10.8 ms vs. CRT 85.1 ± 14.9 ms, p < .01).
Severe LV His-Purkinje conduction disease attenuates the benefits of CSP, with additional improvements achieved with HOT-CRT and LOT-CRT. Septal but not lateral wall scars make CSP ineffective.
希氏束起搏（HBP）或左束支起搏（LBBP）形式的传导系统起搏（CSP）正在成为一种有价值的心脏再同步治疗（CRT）方法。然而，CSP 传递的患者选择和治疗个性化仍然描述不足。我们旨在使用计算模型比较 CRT、HBP、LBBP、HBP 联合左心室（LV）心外膜导联（希氏优化 CRT [HOT-CRT]）和 LBBP 联合 LV 心外膜导联（LBBP 优化 CRT [LOT-CRT]）在具有不同传导疾病表现的患者中的起搏诱导的电同步。
我们在 24 个四腔心几何图形上模拟心室激活，包括近端左束支传导阻滞（LBBB）的希氏-浦肯野系统。我们通过将传导速度（CV）降低到健康 CV 的 70%和 35%来模拟室间隔瘢痕、LV 外侧壁瘢痕以及轻度和重度心肌和 LV 希氏-浦肯野系统传导疾病。电同步通过激活 90%心室的最短间隔（双心室激活时间 90%[BIVAT-90]）来测量。
严重的 LV 希氏-浦肯野传导疾病有利于 CRT（BIVAT-90：HBP 101.5±7.8ms 与 CRT 93.0±8.9ms，p<.05），HOT-CRT（87.6±6.7ms，p<.05）和 LOT-CRT（73.9±7.6ms，p<.05）诱导额外的电同步。与 CRT 相比，CV 较慢的心肌患者从 CSP 中获益更多（BIVAT-90：CRT 134.5±24.1ms；HBP 97.1±9.9ms，p<.01；LBBP：101.5±10.7ms，p<.01）。室间隔而不是外侧壁瘢痕使 CSP 无效，而 CRT 能够在存在室间隔瘢痕的情况下使心室再同步（BIVAT-90：基线 119.1±10.8ms 与 CRT 85.1±14.9ms，p<.01）。
严重的 LV 希氏-浦肯野传导疾病减弱了 CSP 的益处，通过 HOT-CRT 和 LOT-CRT 可进一步改善。室间隔而不是外侧壁瘢痕使 CSP 无效。
