Wu Suhua, Kerwin Walter F, Peter C Thomas, Gang Eli S, Ma Hong
Department of Cardiology, First Affiliated Hospital, Sun Yat-Sen University, No. 58 Zhongshan road 2, GuangZhou 510080, China.
Acta Cardiol. 2007 Apr;62(2):163-9. doi: 10.2143/AC.62.2.2020237.
Ventricular tachycardia (VT) may be haemodynamically unstable or non-sustained, interfering with detailed activation mapping. Non-contact mapping permits beat-by-beat analysis of VT, projected upon a 3-dimensional reconstructed geometry of the cardiac chamber. Objective - The aim of the present study is to determine the utility of non-contact endocardial mapping to guide ablation of haemodynamically unstable VT or non-sustained VT.
Eighteen VTs in 17 patients were induced (cycle length 336 +/- 58 ms) and mapped. Three patients were mapped during premature ventricular complexes (PVCs) because sustained VT could not be induced. Analysis of the archived non-contact activation maps was performed to identify the exit point and/or the diastolic pathway of theVT reentry circuit. The endocardial exit points (10 +/- 16 ms before QRS) were defined in 17/18 VTs (94%). A diastolic pathway was identified in 5/6 ischaemic VTs. The earliest activation sites were identified in all 3 patients with PVCs. Radiofrequency current was applied around the exit point or to create a line of block across the diastolic pathway. Catheter ablation was performed in 17/18 VTs, including 3 patients mapped using only PVCs. Ablation was successful in 16/18 VTs (89%) and in 1 5/17 patients (82%). Catheter ablation was not performed in one patient (peri-hisian VT) and was unsuccessful in one patient (mapped during PVCs).
Non-contact endocardial mapping is useful to guide radiofrequency catheter ablation of untolerated or non-sustained VTs.
室性心动过速（VT）可能在血流动力学上不稳定或为非持续性，这会干扰详细的激动标测。非接触式标测允许逐搏分析VT，并将其投影到心腔的三维重建几何结构上。目的——本研究的目的是确定非接触式心内膜标测在指导血流动力学不稳定的VT或非持续性VT消融中的实用性。
在17例患者中诱发了18次VT（周长336±58毫秒）并进行标测。3例患者在室性早搏（PVC）期间进行标测，因为无法诱发持续性VT。对存档的非接触式激动标测进行分析，以确定VT折返环的出口点和/或舒张期路径。在17/18次VT（94%）中确定了心内膜出口点（在QRS波之前10±16毫秒）。在5/6次缺血性VT中识别出舒张期路径。在所有3例PVC患者中均识别出最早激动部位。在出口点周围施加射频电流或创建一条穿过舒张期路径的阻滞线。18次VT中的17次进行了导管消融，包括3例仅使用PVC进行标测的患者。18次VT中的16次（89%）以及17例患者中的15例（82%）消融成功。1例患者（希氏束周围VT）未进行导管消融，1例患者（在PVC期间进行标测）消融失败。
非接触式心内膜标测有助于指导对无法耐受的或非持续性VT进行射频导管消融。
