Barker Joseph, Sau Arunashis, Bajaj Nikesh, Jenkins Alex, Sharp Alex, Shi Xili, Li Xinyang, Karim Nabeela, Handa Balvinder, Chambers Richard, Betts Timothy, Peters Nicholas S, Wong Tom, Ng Fu Siong
National Heart and Lung Institute, Imperial College London, London, United Kingdom.
Department of Cardiology, Imperial College Healthcare NHS Trust, London, United Kingdom.
Heart Rhythm O2. 2025 May 11;6(8):1097-1105. doi: 10.1016/j.hroo.2025.05.002. eCollection 2025 Aug.
Adjunctive posterior wall isolation (PWI) to pulmonary vein isolation (PVI) has not demonstrated convincing benefit during atrial fibrillation (AF) ablation. To provide mechanistic insight for null PWI trials, we undertook Granger causality (GC) analysis of noncontact left atrial (LA) electroanatomic maps.
This study aimed to apply GC to intracardiac electrograms to uncover patient-specific AF dynamics and describe a proof-of-concept approach to targeted PWI after PVI.
A prospective cohort study was undertaken at Royal Brompton Hospital. Consecutive patients undergoing PVI with noncontact mapping (AcQmap; Acutus Medical) before and after PVI were included.
In 21 patients, causality pairing index, a GC measure of organization, was unchanged after PVI (overall, 0.087 ± 0.012 vs 0.086 ± 0.015; = .64) or by region (posterior wall [PW], 0.084 ± 0.020 vs 0.079 ± 0.017; = .20; rest of LA, 0.087 ± 0.013 vs 0.086 ± 0.016; = .80). Directional dispersion, quantifying conduction heterogeneity, was lower in the PW than the rest of the LA (0.093 ± 0.036 vs 0.11 ± 0.043; = .017) and increased after PVI (0.093 ± 0.036 vs 0.12 ± 0.043; = .045), whereas there was no change in the rest of the LA (0.11 ± 0.034 vs 0.11 ± 0.030; = .52). PW net outflow overall decreased after PVI (before, -0.0086 ± 0.047 vs -0.033 ± 0.054; = .011) with a minority of patients exhibiting a net positive outflow from the PW.
GC provides mechanistic insight into the null trials for PWI and identifies a minority of patients who may benefit. GC is positioned as a clinical decision tool to guide personalized persistent AF ablation strategies.
在心房颤动（AF）消融过程中，肺静脉隔离（PVI）联合后壁隔离（PWI）尚未显示出令人信服的益处。为了深入了解PWI无效试验的机制，我们对非接触式左心房（LA）电解剖图进行了格兰杰因果关系（GC）分析。
本研究旨在将GC应用于心内电图，以揭示患者特异性AF动态，并描述一种PVI后靶向PWI的概念验证方法。
在皇家布朗普顿医院进行了一项前瞻性队列研究。纳入在PVI前后接受非接触式标测（AcQmap；Acutus Medical）的连续PVI患者。
在21例患者中，因果配对指数（一种组织的GC测量指标）在PVI后未发生变化（总体上，0.087±0.012对0.086±0.015；P = 0.64），按区域分析也未变化（后壁[PW]，0.084±0.020对0.079±0.017；P = 0.20；LA其余部分，0.087±0.013对0.086±0.016；P = 0.80）。量化传导异质性的方向离散度在PW中低于LA其余部分（0.093±0.036对0.11±0.043；P = 0.017），且在PVI后增加（0.093±0.036对0.12±0.043；P = 0.045），而LA其余部分无变化（0.11±0.034对0.11±0.030；P = 0.52）。PVI后PW的总净流出量总体下降（之前，-0.0086±0.047对-0.033±0.054；P = 0.011），少数患者的PW呈现净正流出。
GC为PWI的无效试验提供了机制性见解，并识别出少数可能受益的患者。GC可作为一种临床决策工具，以指导个性化的持续性AF消融策略。
