Assessing the ability of substrate mapping techniques to guide ventricular tachycardia ablation using computational modelling
Assessing the ability of substrate mapping techniques to guide ventricular tachycardia ablation using computational modelling
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DOI：
10.1016/j.compbiomed.2021.104214
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发表时间：
2021-01-18
影响因子：
7.7
通讯作者：
Bishop, Martin J.
中科院分区：
文献类型：
--
作者：
Campos, Fernando O.;Orini, Michele;Bishop, Martin J.
背景：确定梗死后室性心动过速（VTs）的消融靶点仍然具有挑战性，通常需要心律失常诱导来描绘重入回路。这对病人有风险，可能不可行。底物定位已成为一种更安全的发现心律失常区域的策略。然而，室速复发仍然很常见。目的：利用计算机模拟来评估不同基底映射方法识别VT出口位置的能力。方法：建立猪梗死后心脏三维计算模型，模拟室速和心律。根据心内膜电图特征和再入脆弱性指数（RVI，一种结合激活（AT）和复极时间的指标，用于识别组织对再入的易感性）构建电解剖图。由于我们的模型中的疤痕跨界性不是均匀的，因此在分析中使用了来自所有信号（包括密集疤痕区域）的参数。将起搏期间每个电解剖图获得的潜在消融目标与VT测图检测到的出口位置进行比较。结果：模拟数据显示，对双极电图施加电压切断可以描绘疤痕，但不能描绘VT电路。电图分划与瘢痕跨壁性相关性最高。RVI识别出最接近VT出口的区域，但AT梯度结合电压切断优于RVI。所有指标的性能都受到起搏位置的影响。结论：底物定位可以提供梗死信息，但应考虑对激活的方向性依赖。激活-复极化指标在安全识别VT靶时很有用，即使是非跨壁疤痕。
Background: Identification of targets for ablation of post-infarction ventricular tachycardias (VTs) remains challenging, often requiring arrhythmia induction to delineate the reentrant circuit. This carries a risk for the patient and may not be feasible. Substrate mapping has emerged as a safer strategy to uncover arrhythmogenic regions. However, VT recurrence remains common.Goal: To use computer simulations to assess the ability of different substrate mapping approaches to identify VT exit sites.Methods: A 3D computational model of the porcine post-infarction heart was constructed to simulate VT and paced rhythm. Electroanatomical maps were constructed based on endocardial electrogram features and the reentry vulnerability index (RVI a metric combining activation (AT) and repolarization timings to identify tissue susceptibility to reentry). Since scar transmurality in our model was not homogeneous, parameters derived from all signals (including dense scar regions) were used in the analysis. Potential ablation targets obtained from each electroanatomical map during pacing were compared to the exit site detected during VT mapping.Results: Simulation data showed that voltage cut-offs applied to bipolar electrograms could delineate the scar, but not the VT circuit. Electrogram fractionation had the highest correlation with scar transmurality. The RVI identified regions closest to VT exit site but was outperformed by AT gradients combined with voltage cut-offs. The performance of all metrics was affected by pacing location.Conclusions: Substrate mapping could provide information about the infarct, but the directional dependency on activation should be considered. Activation-repolarization metrics have utility in safely identifying VT targets, even with non-transmural scars.