Egami Yasuyuki, Matsunaga-Lee Yasuharu, Yano Masamichi, Nishino Masami
Division of Cardiology, Osaka Rosai Hospital, Sakai, Osaka, Japan.
Indian Pacing Electrophysiol J. 2024 Nov-Dec;24(6):361-365. doi: 10.1016/j.ipej.2024.09.006. Epub 2024 Sep 18.
Macroreentrant atrial tachycardia (ATs) through epicardial conduction is depicted as a focal AT on 3-D mapping, i.e., pseudo-focal AT. A new feature of the Rhythmia mapping system (Boston Scientific), the "LUMIPOINT module", can highlight all electrocardiograms (EGMs) above a threshold determined by an adjustable confidence slider (CS). Lowering the CS (L-CS) may highlight undetected electrograms (EGMs) at the nominal CS setting, potentially enabling visualization of the critical isthmus of pseudo-focal ATs.
This study included 3 ATs after linear ablation of two left atrial roof-dependent ATs (cases 1 and 2) and one peri-mitral flutter (case 3). All ATs were diagnosed as pseudo-focal AT according to an electrophysiological study and the Rhythmia mapping system with the LUMIPOINT module. The L-CS method consisted of the following steps: 1. Set the LUMIPOINT activation window to the time difference before and after the linear ablation line. 2. Highlight the two regions before and after the linear ablation line. 3. Gradually lower the CS value from the nominal setting of 85 % by 5-10 %. By the L-CS method in cases 1-3, the 2-sided highlighted areas before and after the prior linear ablation lesion gradually expanded and eventually fused. EGMs at the fusion sites of the highlighted areas exhibited fragmented EGMs with a low voltage, where a single-shot ablation terminated the targeted ATs.
The L-CS method was useful for the visualization of residual gaps and identification of targeted ablation sites in cases of pseudo-focal AT after linear ablation of macroreentrant ATs.
通过心外膜传导的大折返性房性心动过速（ATs）在三维标测时表现为局灶性AT，即假性局灶性AT。Rhythmia标测系统（波士顿科学公司）的一项新功能“LUMIPOINT模块”，可以突出显示高于由可调置信度滑块（CS）确定的阈值的所有心电图（EGM）。降低CS（L-CS）可能会突出在标称CS设置下未检测到的电图（EGM），从而有可能使假性局灶性AT的关键峡部可视化。
本研究纳入了3例AT，分别为2例左心房顶部依赖性AT（病例1和2）和1例二尖瓣周围扑动（病例3）线性消融术后。根据电生理研究和带有LUMIPOINT模块的Rhythmia标测系统，所有AT均被诊断为假性局灶性AT。L-CS方法包括以下步骤：1. 将LUMIPOINT激活窗口设置为线性消融线前后的时间差。2. 突出显示线性消融线前后的两个区域。3. 从标称设置的85%开始，以5%-10%的幅度逐渐降低CS值。通过L-CS方法，在病例1-3中，先前线性消融灶前后的双侧突出区域逐渐扩大并最终融合。突出区域融合部位的EGM表现为低电压的碎裂EGM，单次消融可终止目标AT。
L-CS方法有助于在大折返性AT线性消融后的假性局灶性AT病例中可视化残留间隙并识别目标消融部位。
