Peri-procedural transmural electrophysiological imaging of scar-related ventricular tachycardia

项目摘要 室性心动过速（VT）是心脏病患者死亡和致残的重要原因。 大多数危及生命的室性心动过速发作是由电气“短路”引起的， 心肌瘢痕内存活组织的通道。瘢痕相关VT的重要治疗是靶向和 破坏这些慢传导通道有效的消融需要能够描绘出 电路的形态，以识别慢传导通道。不幸的是，传统的 在导管标测中，高达90%的室性心动过速回路寿命太短，无法标测。对于10%的“可映射”VT， 它们的数据仅在消融期间可用并且限于一个心室表面。这种不足之处， 功能性室性心动过速数据在很大程度上限制了我们目前对瘢痕相关室性心动过速和消融策略的了解， 降低了临床医生识别消融靶点和评估消融结果的能力。这个目标 建议开发一种新技术，以提供消融前和消融后功能性VT数据-与 3D LGE-MRI疤痕数据-通过术前识别消融靶点改善VT消融， 消融失败的术后机制说明。它建立在快速增长的临床兴趣， 心电图成像（ECGi）是一种新兴技术，其通过以下方式获得心脏电活动： 体表心电图的逆向重建其具体目标包括： 1)开发并确认用于标测瘢痕相关VT回路的围手术期ECGi。 2)将LGE-MRI瘢痕整合到ECGi中，以改善VT回路的电解剖研究。 3)对瘢痕相关性室性心动过速消融前后的MRI-ECGi进行临床评价。 这些研究将在40例因既往心脏病导致VT的前瞻性队列中进行。 梗塞这项研究建立在我们先前建立的透壁ECGi技术基础上， 在美国国立卫生研究院探索性拨款的支持下产生的有希望的初步数据。它进一步得到以下方面的支持： 每个分包商实验室之前的技术和临床进展，包括基于相机的躯干 建模（Siemens）、壁内标测和消融（NSHA）以及VT中的LGE-MRI瘢痕成像（UPenn）。的 这项研究的结果将产生关于瘢痕相关的电解剖机制的新知识， 室性心动过速和消融失败的机制。它将实现3D功能的术前和术后标测 所有诱导性室性心动过速的回路，提高临床医生识别消融靶点和评估消融的能力 结果。最后，它将及时提供下一代ECGi技术，以进一步发展我们的通用技术。 能够在更广泛的心脏中进行更安全、更有效的心脏电生理学研究 疾病

Project Summary Ventricular tachycardia (VT) is an important cause of mortality and morbidity in patients with heart diseases. The majority of life-threatening VT episodes are caused by an electrical "short circuit", formed by a narrow channel of surviving tissue inside myocardial scar. An important treatment for scar-related VT is to target and destroy these culprit slow-conducting channels. Effective ablation requires the ability to delineate the morphology of the circuit in order to identify the slow-conducting channels. Unfortunately, with conventional catheter mapping, up to 90% of the VT circuits are too short-lived to be mapped. For the 10% “mappable” VTs, their data are available only during ablation and limited to one ventricular surface. This inadequacy of functional VT data largely limits our current knowledge about scar-related VT and ablation strategies, and reduces the ability of clinicians to identify ablation targets and assess ablation outcome. The goal of this proposal is to develop a novel technique to provide pre- and post-ablation functional VT data – integrated with LGE-MRI scar data in 3D – to improve VT ablation with pre-procedural identification of ablation targets and post-procedural mechanistic elucidation of ablation failure. It builds on the rapidly increasing clinical interest in electrocardiographic imaging (ECGi), an emerging technique that obtains cardiac electrical activity through inverse reconstructions from body-surface ECGs. Its specific objectives include: 1) To develop and validate a peri-procedural ECGi for mapping scar-related VT circuits. 2) To integrate LGE-MRI scar into ECGi for improved electroanatomical investigations of VT circuits. 3) To perform clinical evaluation of pre-ablation and post-ablation MRI-ECGi of scar-related VT. These investigations will be carried out on a prospective cohort of 40 patients with VT due to previous infarction. This research builds on our previously established technical foundation for transmural ECGi and promising preliminary data generated under the support of our exploratory NIH grant. It is further supported by previous technical and clinical advances in each of the subcontractors' lab, including camera-based torso modeling (Siemens), intramural mapping and ablation (NSHA), and LGE-MRI scar imaging in VT (UPenn). The outcome of this research will generate new knowledge about the electroanatomical mechanism of scar-related VT and the mechanism behind ablation failure. It will enable pre- and post-procedural mapping of 3D functional circuits of all inducible VTs, improving the ability of clinicians to identify ablation targets and assess ablation outcome. Finally, it will timely deliver the next generation of ECGi techniques to further our general technical capability for safer and more efficient cardiac electrophysiological studies in a broader variety of heart diseases.