BioLab3, Biomedical Engineering Laboratory, Roma Tre University, Rome, Italy.
Arrhythmology Unit, Hospital Fatebenefratelli Isola Tiberina-Gemelli Isola, Rome, Italy.
J Interv Card Electrophysiol. 2023 Apr;66(3):647-660. doi: 10.1007/s10840-022-01339-1. Epub 2022 Sep 30.
Spatial differences in conduction velocity (CV) are critical for cardiac arrhythmias induction. We propose a method for an automated CV calculation to identify areas of slower conduction during cardiac arrhythmias and sinus rhythm.
Color-coded representations of the isochronal activation map using data coming from the RHYTHMIA™ Mapping System were reproduced by applying a temporal isochronal window at 20 ms. Geodesic distances of the 3D mesh were calculated using an algorithm selecting the minimum distance pathway (MDP). The CV estimation was performed considering points on the boundary of two spatially and temporally adjacent isochrones. For each of the boundary points of a given isochrone, the nearest boundary point of the consecutive isochrone was chosen, the MDP was evaluated, and a map of CV was created. The proposed method has been applied to a population of 29 patients.
In all cases of perimitral atrial flutter (16 pts out of 29 (55%)), areas with significantly low CV (< 30 cm/s) were found. Half of the cases present regions with low CV located in the anterior wall. No case with low CV at the so-called LA isthmus was observed. Right atrial maps during common atrial flutters showed low CV areas mainly located in the inferior inter-atrial septum. No areas of low CV were observed in subjects without a history of atrial arrhythmia while pts affected by paroxysmal AF showed areas with a limited extension of low CV.
The proposed software for automated CV estimation allows the identification of low CV areas, potentially helping electrophysiologists to plan the ablation strategy.
传导速度（CV）的空间差异对心脏心律失常的诱导至关重要。我们提出了一种自动计算 CV 的方法，以识别心脏心律失常和窦性节律期间传导较慢的区域。
使用来自 RHYTHMIA™ Mapping System 的数据，通过应用 20 毫秒的时间等时窗口，再现等时激活图的彩色编码表示。使用选择最短距离路径（MDP）的算法计算 3D 网格的测地距离。考虑两个空间和时间上相邻等时线边界上的点来进行 CV 估计。对于给定等时线的每个边界点，选择相邻等时线的最近边界点，评估 MDP，并创建 CV 图。该方法已应用于 29 名患者的人群。
在所有间隔性心房扑动（29 例中的 16 例（55%））的情况下，都发现了 CV 明显较低（<30cm/s）的区域。半数病例的低 CV 区域位于前壁。在所谓的 LA 峡部没有观察到低 CV 区。在常见的心房扑动期间，右心房图显示低 CV 区域主要位于下房间隔。在没有心房心律失常病史的患者中未观察到低 CV 区，而阵发性 AF 患者则显示出低 CV 区的扩展有限。
提出的自动 CV 估计软件允许识别低 CV 区，这可能有助于电生理学家规划消融策略。
