International Circulation: There is relative little clinical data available about catheter ablation of ventricular tachycardia compared to atrial fibrillation. What are the indications for ablation in patients with VT?

　　《国际循环》：导管消融治疗室性心动过速的临床数据与房颤相比要少很多。室速患者消融的指征是什么呢?

　　Young－Hoon Kim: The indications for ablation of VT are firstly， symptomatic documented wide QRS tachycardias which are diagnosed as ventricular tachycardias regardless of the stability of hemodynamics. Also， we need to consider the cause and mechanism for the patient’s VT. We need to identify the underlying disease such as myocardial infarction， cardiomyopathy， and also genetically determined diseases like arrhythmic right ventricular cardiomyopathy or others. In those cases， if the patient has a sustained monomorphic VT， he is going to be a good candidate for VT catheter ablation. Also， patients with recent frequent PVCs or non-sustained VT， especially with a lower ejection fraction from the early stage of cardiomyopathy will also be good candidates for catheter ablation. In these patients the post-ablation ejection fraction is significantly improved. In conclusion， symptoms， hemodynamics， underlying diseases， and recent frequent PVCs which are more than 20% in 24 hour monitoring are indicators for catheter ablation in patients with VT. Also， the high-risk patient who has already had ICD implantation with frequent shocks can be considered because frequent shocks significantly reduce the quality of life， hemodynamics， and also introduces a high risk of mortality in patients after implantation of ICD. Catheter ablation would reduce the shock frequency or even eliminate shocks.

　　Young－Hoon Kim教授：室性心动过速(VT)导管消融术的适应证，首先是有症状的宽QRS波心动过速被诊断为VT，而不论其血液动力学的稳定性。其次，我们需要考虑VT患者发病的原因和机制，识别是否由心肌梗死、心肌病或遗传性疾病如致心律失常性右心室心肌病或其他疾病导致。在那些情况下，如果患者有持续性单形性VT，他就是VT导管消融术的候选者。另外，近期频发室性期前收缩或者非持续性VT，尤其是心肌病早期阶段射血分数较低的患者，同样也适合导管消融术，术后射血分数可以明显增加。总之，症状、血流动力学、基础疾病和近期频发室性期前收缩(24小时动态监测大于20%)，都是VT导管消融术的适应证。另外，安装ICD后频繁电击的高危患者，可以考虑导管消融，因为频繁电击严重降低了生活质量、恶化血流动力学指标、增加ICD植入后死亡率。导管消融术能降低电击的频率，甚至根除电击。