Department of Physiology, Maastricht University, 6211 LK Maastricht, The Netherlands University Heart Center, Department of Cardiology and Electrophysiology, University Hospital Hamburg-Eppendorf, 20246 Hamburg, Germany
Department of Physiology, Maastricht University, 6211 LK Maastricht, The Netherlands Department of Cardiothoracic Surgery, Maastricht University Medical Centre, 6202 AZ Maastricht, The Netherlands.
Europace. 2014 Nov;16 Suppl 4:iv135-iv140. doi: 10.1093/europace/euu247.
Mapping and interpretation of wave conduction patterns recorded during simultaneous mapping of the electrical activity on both endocardial and epicardial surfaces are challenging because of the difficulty of reconstruction of reciprocal alignment of electrodes in space. Here, we suggest a method to overcome this difficulty using a concept of maximized endo-epicardial phase coherence.
Endo-epicardial mapping was performed in six humans during induced atrial fibrillation (AF) in right atria using two sets of 8 × 8 electrode plaques. For each electrode, mean phase coherence (MPC) with all electrodes on the opposite side of the atrial wall was calculated. Localization error was defined as a distance between the directly opposing electrode and the electrode with the maximal MPC. Overall, there was a linear correlation between MPC and distance between electrodes with R(2) = 0.34. Localization error obtained for electrodes of the plaque in six patients resulted in a mean 2.3 ± 1.9 mm for 25 s electrogram segment length. Eighty-four per cent of the measurements resulted in error smaller than 3.4 mm. The duration of the recording used to compute MPC was negatively correlated with localization error; however, the effect reached plateau for segment durations longer than 15 s.
Application of the concept of maximized endo-epicardial phase coherence to electrograms during AF allows reconstruction of reciprocal alignment of the electrodes on the opposite side of the atrial wall. This approach may be especially useful in settings where the spatial position of endo- and epicardial electrodes for intracardiac mapping cannot otherwise be determined.
在同时记录心内膜和心外膜表面电活动时，由于难以重建电极在空间中的相互对准，因此对记录的波传导模式进行映射和解释具有挑战性。在这里，我们建议使用最大化心内膜-心外膜相位相干性的概念来克服这一困难。
在使用两套 8×8 电极板在右心房中诱发心房颤动（AF）期间，在 6 个人中进行了心内膜-心外膜标测。对于每个电极，计算与心房壁相对侧的所有电极的平均相位相干性（MPC）。定位误差定义为直接相对电极与具有最大 MPC 的电极之间的距离。总体而言，MPC 与电极之间的距离之间存在线性相关性，R² = 0.34。在 6 名患者的斑块电极上获得的定位误差导致 25 秒电描记片段长度的平均 2.3 ± 1.9 毫米。84％的测量结果误差小于 3.4 毫米。用于计算 MPC 的记录持续时间与定位误差呈负相关；然而，对于大于 15 秒的片段持续时间，效果达到了平台期。
在 AF 期间应用最大化心内膜-心外膜相位相干性的概念来记录电图，可以重建心房壁相对侧电极的相互对准。在其他情况下无法确定心内标测的心内膜和心外膜电极的空间位置的情况下，这种方法可能特别有用。
