Department of Cardiovascular Medicine, Tokyo Medical and Dental University Hospital, Tokyo, Japan.
Department of Cardiovascular Medicine, Tokyo Medical and Dental University Hospital, Tokyo, Japan; Division of Advanced Arrhythmia Research, Tokyo Medical and Dental University Hospital, Tokyo, Japan.
Heart Rhythm. 2024 Aug;21(8):1382-1389. doi: 10.1016/j.hrthm.2024.03.002. Epub 2024 Mar 7.
Unipolar electrograms (uni-EGMs) are an essential part of intracardiac mapping. Although Wilson central terminal (WCT) is conventionally used as a reference for signals, avoidance of contamination by far-field and nonphysiologic signals is challenging.
The aim of the study was to explore the impact of an intracardiac indifferent reference electrode close to the recording electrodes, in lieu of WCT, on electrograms.
Sinus node activation was mapped in patients undergoing catheter ablation by a multielectrode array with a close indifferent electrode (CIE) embedded in the distal end of the catheter shaft. An equal number of points was sequentially acquired at each site with use of CIE as a reference first and subsequently with WCT. Uni-EGMs, bipolar EGMs, and the earliest activation area (defined as the area activated in the first 10 ms of the beat) were compared between CIE- and WCT-based activation maps.
Seventeen patients (61 ± 18 years; 76% male) were studied. Uni-EGM voltages acquired with CIE were significantly larger than (n = 11) or comparable to (n = 4) those acquired with WCT. When points from the entire cohort were analyzed altogether, unipolar voltages and their maximum negative dV/dT and bipolar voltages recorded with CIE were significantly larger than those recorded with WCT (2.36 [1.42-3.79] mV vs 1.96 [1.25-3.03] mV, P < .0001; 0.40 [0.18-0.77] mV/s vs 0.35 [0.15-0.71] mV/s, P < .0001; and 1.46 [0.66-2.81] mV vs 1.33 [0.54-2.64] mV, P < .0001, respectively). The earliest activation area was significantly smaller in CIE-based activation maps than in WCT-based ones (0.3 [0.7-1.4] cm vs 0.6 [1.0-1.8] cm, P = .01).
CIE-based maps were associated with an approximately 20% increase in unipolar voltage and may highlight the origin of a focal activation more clearly than WCT-based ones.
单极电图（uni-EGMs）是心内标测的重要组成部分。尽管威尔逊中心终端（WCT）通常被用作信号参考，但要避免远场和非生理信号的污染仍然具有挑战性。
本研究旨在探讨在记录电极附近使用心内无关参考电极（CIE）替代 WCT 对电图的影响。
通过多电极阵列对接受导管消融的患者进行窦房结激活标测，该多电极阵列在导管轴的远端嵌入了一个紧密的无关电极（CIE）。首先使用 CIE 作为参考，然后使用 WCT，依次在每个部位获取相同数量的点。比较 CIE 和 WCT 激活图之间的 uni-EGM、双极 EGM 和最早激活区（定义为在搏动的前 10 毫秒内激活的区域）。
研究了 17 名患者（61 ± 18 岁；76%为男性）。使用 CIE 获得的 uni-EGM 电压明显大于（n = 11）或与 WCT 获得的 uni-EGM 电压相当（n = 4）。当对整个队列的点进行分析时，使用 CIE 记录的单极电压及其最大负 dV/dT 和双极电压明显大于使用 WCT 记录的电压（2.36 [1.42-3.79] mV 比 1.96 [1.25-3.03] mV，P<0.0001；0.40 [0.18-0.77] mV/s 比 0.35 [0.15-0.71] mV/s，P<0.0001；1.46 [0.66-2.81] mV 比 1.33 [0.54-2.64] mV，P<0.0001）。CIE 激活图上的最早激活区明显小于 WCT 激活图上的激活区（0.3 [0.7-1.4] cm 比 0.6 [1.0-1.8] cm，P=0.01）。
基于 CIE 的图谱与单极电压增加约 20%有关，并且可能比基于 WCT 的图谱更清晰地突出局灶性激活的起源。
