Substrate Mapping & Ablation of Ventricular Tachycardia

描述（由申请人提供）： 在有心源性猝死风险的冠心病患者中，恶性心室肌功能不全和心源性心脏病患者中， 心动过速（VT）的治疗与植入式除颤器和抗心律失常药物的组合 毒品虽然有效地预防心脏性猝死，但这种策略受到以下因素的困扰： 药物副作用和毒性，以及器械相关医源性并发症。理想 室性心动过速的治疗是消除心律失常。这可以通过以下方式实现： 通过手术切除梗死的致瘤组织，疗效大于90%; 然而，这是一种与显著发病率和死亡率相关开放性外科手术。 射频（RF）导管消融是一种有效的微创替代方法，但在很大程度上 仅限于血流动力学耐受的VT-占所有VT的不到10%。然而，在这方面， 室性心动过速的导管消融方法正在经历范式转变。而不是试图 为了精确识别心动过速期间VT回路的关键部分， 在窦性心律下进行以识别致炎组织。然后，一种概率方法 使用战略性放置的线性射频损伤进行导管消融。虽然这种策略 在小型非随机研究中已被证明是成功的， 输送射频消融的方法未知。此外，基底烧蚀在主要 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）比较标准非灌注与盐水灌注射频消融 基质标测和消融导管在多个ICD患者中的应用 电击（THERMO COOL IDE试验），和B）检查底物标测和RF的作用 ICD电击一级预防中的消融（SMASH-VT试验）。此外， 一个新的三维绘图系统，以迅速确定致癌底物， 在具有诱导性VT的愈合的心肌梗死的猪模型中检查。最后利用 这种先进的标测系统，以确定基板，导管介导的效果， 冷冻消融将与在诱导导管上使用盐水灌注导管的射频消融进行比较 VT的发生率。

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.