Substrate Mapping & Ablation of Ventricular Tachycardia

描述(由申请人提供)： 在有心脏性猝死风险的冠心病患者中，恶性室壁 心动过速(VT)用植入式除颤器和抗心律失常药联合治疗 毒品。虽然这一策略在预防心源性猝死方面很有效，但也受到了 药物副作用和毒性，以及与设备相关的医源性并发症。理想 室性心动过速的治疗方法是消除心律失常。这可以通过以下方式实现 手术切除梗死性致心律失常组织的有效率大于90%； 然而，这是一种与显著的发病率和死亡率相关的开放式外科手术。 射频导管消融术是一种有效的、侵入性较小的选择，但在很大程度上 仅限于血流动力学耐受的室性心动过速--占所有室速的不到10%。然而， 导管消融室性心动过速的方法正在经历一种范式的转变。与其试图 准确识别心动过速期间室速回路的关键部位，“底物标测”是 在窦性节律下进行，以识别致心律失常的组织。然后，一种概率方法 TO导管消融是使用战略性放置的线性射频损伤进行的。虽然这一战略 在小型非随机研究中被证明是成功的，最安全和最有效的 射频消融的方法尚不清楚。另外，基质消融在一期手术中的作用。 ICD电击的预防尚不清楚。我们现在建议进行前瞻性随机 临床试验：a)比较标准的非灌溉射频消融术和盐水灌溉射频消融术 基质标测消融导管在多发性ICD治疗中的应用 电击(Thermo Cool IDE试验)，以及b)检查衬底映射和射频的作用 消融在ICD休克一级预防中的作用(SMASH-VT试验)。此外，还可以提高 一种新的三维标测系统将用于快速识别致心律失常的底物 在可诱导性室性心动过速的治愈心肌梗死猪模型中进行检查。最后，使用 这种先进的标测系统能够识别底物、导管介导的效果 冷冻消融与使用盐水冲洗导管的射频消融在诱导性上进行比较。 VT在这个动物模型系统中的作用。

DESCRIPTION (provided by applicant): In patients with coronary artery disease at risk for sudden cardiac death, malignant ventricular tachycardia (VT) is treated with a combination of implantable defibrillators and antiarrhythmic drugs. While effective in preventing sudden cardiac death, this strategy is plagued with medication side-effects and toxicities, and device related iatrogenic complications. The ideal treatment for VT would be eradication of the arrhythmia. This can be accomplished with greater than 90% efficacy through surgical resection of the infarcted arrhythmogenic tissue; however, this is an open surgical procedure associated with significant morbidity and mortality. Radiofrequency (RF) catheter ablation is an effective less-invasive alternative, but is largely limited to hemodynamically-tolerated VT-which accounts for less than 10% of all VT. However, the approach to catheter ablation of VT is undergoing a paradigm shift. Instead of trying to precisely identify the critical portions of the VT circuit during tachycardia, "substrate mapping" is performed in sinus rhythm to identify the arrhythmogenic tissue. Then, a probabilistic approach to catheter ablation is undertaken using strategically-placed linear RF lesions. While this strategy has proven to be successful in small non-randomized studies, the safest and most efficacious method to deliver the RF ablation is not known. Also, the role of substrate ablation in the primary prevention of ICD shocks is unknown. We now propose to conduct prospective randomized clinical trials: a) comparing the standard non-irrigated to the saline-irrigated RF ablation catheter for substrate-mapping and ablation in the treatment of patients with multiple ICD shocks (the THERMO COOL IDE trial), and b) examining the role of substrate-mapping and RF ablation in the primary prevention of ICD shocks (the SMASH-VT trial). Furthermore, the abilitv of a new 3-dimensional mapping system to rapidly identify the arrhythmogenic substrate will be examined in a porcine model of healed myocardial infarction with inducible VT. Finally, using this advanced mapping system to identify the substrate, the effect of catheter-mediated cryoablation will be compared to RF ablation using a saline-irrigated catheter on the inducibility of VT in this animal model system.