Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan, USA.
J Am Coll Cardiol. 2010 Sep 14;56(12):969-79. doi: 10.1016/j.jacc.2010.04.043.
The purpose of this study was to assess the value of implantable cardioverter-defibrillator (ICD) electrograms (EGMs) in identifying clinically documented ventricular tachycardias (VTs).
Twelve-lead electrocardiograms (ECG) of spontaneous VT often are not available in patients referred for catheter ablation of post-infarction VT. Many of these patients have ICDs, and the ability of ICD EGMs to identify a specific configuration of VT has not been described.
In 21 consecutive patients referred for catheter ablation of post-infarction VT, 124 VTs (mean cycle length: 393 ± 103 ms) were induced, and ICD EGMs were recorded during VT. Clinical VT had been documented with 12-lead ECGs in 15 of 21 patients. The 12-lead ECGs of the clinical VTs were compared with 64 different inducible VTs (mean cycle length: 390 ± 91 ms) to assess how well the ICD EGMs differentiated the clinical VTs from the other induced VTs. The exit site of 62 VTs (mean cycle length: 408 ± 112 ms) was identified by pace mapping (10 to 12 of 12 matching leads). The spatial resolution of pace mapping to identify a VT exit site was determined for both the 12-lead ECGs and the ICD EGMs using a customized MATLAB program (version 7.5, The MathWorks, Inc., Natick, Massachusetts).
Analysis of stored EGMs by comparison of receiver-operating characteristic curve cutoff values accurately distinguished the clinical VTs from 98% of the other inducible VTs. The mean spatial resolution of a 12-lead ECG pace map for the VT exit site was 2.9 ± 4.0 cm(2) (range 0 to 17.5 cm(2)) compared with 8.9 ± 9.0 cm(2) (range 0 to 35 cm(2)) for ICD EGM pace maps. The spatial resolution of pace mapping varied greatly between patients and between VTs. The spatial resolution of ICD EGMs was < 1.0 cm(2) for ≥ 1 of the target VTs in 12 of 21 patients and 19 of 62 VTs. By visual inspection of the ICD EGMs, 96% of the clinical VTs were accurately differentiated from previously undocumented VTs.
Stored ICD EGMs usually are an accurate surrogate for 12-lead ECGs for differentiating clinical VTs from other VTs. Pace mapping based on ICD EGMs has variable resolution but may be useful for identifying a VT exit site.
本研究旨在评估植入式心脏复律除颤器（ICD）心电图（EGM）在识别临床记录的室性心动过速（VT）中的价值。
接受心肌梗死后 VT 导管消融治疗的患者常无法获得自发性 VT 的 12 导联心电图（ECG）。这些患者中有许多人都装有 ICD，ICD EGM 识别特定 VT 形态的能力尚未得到描述。
在 21 例连续接受心肌梗死后 VT 导管消融治疗的患者中，诱发了 124 次 VT（平均周长：393±103ms），并在 VT 期间记录 ICD EGM。21 例患者中有 15 例的临床 VT 通过 12 导联 ECG 记录。将临床 VT 的 12 导联 ECG 与 64 次不同的可诱导 VT（平均周长：390±91ms）进行比较，以评估 ICD EGM 区分临床 VT 和其他诱导 VT 的能力。通过起搏映射（12 个匹配导联中的 10-12 个）确定 62 次 VT（平均周长：408±112ms）的出口部位。使用定制的 MATLAB 程序（版本 7.5，The MathWorks，Inc.，马萨诸塞州纳提克）确定 12 导联 ECG 和 ICD EGM 识别 VT 出口部位的空间分辨率。
通过比较接收器工作特征曲线截断值分析存储的 EGM，可准确区分临床 VT 和 98%的其他可诱导 VT。用于 VT 出口部位的 12 导联 ECG 起搏图的平均空间分辨率为 2.9±4.0cm2（范围 0 至 17.5cm2），而 ICD EGM 起搏图为 8.9±9.0cm2（范围 0 至 35cm2）。起搏图的空间分辨率在患者之间和 VT 之间差异很大。12 个患者中有 12 个，62 个 VT 中有 19 个的目标 VT 中的至少 1 个的 ICD EGM 空间分辨率<1.0cm2。通过对 ICD EGM 的直观检查，96%的临床 VT 与之前未记录的 VT 准确区分。
存储的 ICD EGM 通常是区分临床 VT 和其他 VT 的 12 导联 ECG 的准确替代方法。基于 ICD EGM 的起搏图具有可变的分辨率，但可能有助于识别 VT 出口部位。
