Catheter Guidance System for RF Ablation of Arrhythmias

描述（由申请人提供）：射频（RF）导管消融术是心律失常患者的既定治疗方法。房室结折返性心律失常的RF消融已经非常成功，因为房室结的已知解剖结构使得能够精确识别心律失常的起源部位，从而递送消融能量。室性心动过速（VT）的消融带来了更大的挑战，因为心律失常的起源可能在心室中的任何地方，并且用于定位该部位的现有技术通常需要患者在心律失常中维持相当长的一段时间。这些因素联合收割机限制了手术主要用于治疗心律失常期间血流动力学稳定的患者的缓慢VT。 在本快速通道项目的第I阶段，将证明新导管导引系统的概念可行性，该系统将消融导管的头端引导至心律失常的起源部位，并缩短定位该部位所需的时间，使患者仅需维持心律失常几次搏动。该系统将采用创新的“逆算法”分析代码，该代码使用单个等效移动偶极子（SEMD）来模拟体表电极的心电图（EGG）电位和消融导管头端输送的电流脉冲。通过在VT的几次搏动期间处理身体表面电位，系统将在生物电源最局部化时识别对应于心律失常源的SEMD位置。然后，使用相同的算法，通过分析输送到位于头端的电极的低能偶极电流脉冲产生的电位，真实的识别导管头端的位置。该系统还将包括实时图形显示，允许临床医生快速引导导管头端至心律失常源，以精确输送射频能量。 即使在ECG信号中存在真实水平的噪声的情况下，初步工作已经表明，从体表电位估计SEMD位置是一项突破性创新，其将允许精确、快速地将消融导管引导到脑电病灶。第I阶段将证明开发的试验板系统的可行性，以证明将消融导管引导到体模躯干内电源位置的能力。这项工作将作为第二阶段完整原型制导系统的开发和体内测试的基础。

DESCRIPTION (provided by applicant): Radio frequency (RF) catheter ablation is an established treatment for patients with cardiac arrhythmias. RF ablation of atrio-ventricular nodal reentrant arrhythmias has been highly successful, since the known anatomy of the atrio-ventricular node enables precise identification of the site of origin of the arrhythmia and thus delivery of the ablative energy. Ablation of ventricular tachycardia (VT) presents a greater challenge, since the origin of the arrhythmia could be anywhere in the ventricles, and existing techniques used to locate the site usually require that patients be maintained in arrhythmia for a significant period of time. These factors combine to limit the procedure primarily to treatment of slow VTs in patients who are hemodynamically stable during arrhythmia. In Phase I of this Fast-Track project, concept feasibility will be demonstrated for a new catheter guidance system that will direct the tip of an ablation catheter to the site of origin of an arrhythmia and reduce the time needed to locate the site such that a patient need only be maintained in the arrhythmia for a few beats. The system will feature an innovative "inverse algorithm" analysis code that uses a single equivalent moving dipole (SEMD) to model both electrocardiograph (EGG) potentials from body-surface electrodes and the current pulses delivered from the tip of an ablation catheter. By processing body surface potentials during a few beats of VT, the system will identify the SEMD location that corresponds to the source of the arrhythmia when the bioelectrical source is most localized. Using the same algorithm, it will then identify, in real time, the location of the catheter tip from analysis of potentials resulting from low-energy dipolar current pulses delivered to electrodes located at the tip. The system will also include a real-time graphical display that will allow a clinician to quickly guide the catheter tip to the source of the arrhythmia for precise delivery of RF energy. Even in the presence of realistic levels of noise in the ECG signals, preliminary work has shown that estimation of the SEMD location from body surface potentials is a breakthrough innovation that will allow for precise, rapid guidance of ablation catheters to arrhythmic foci. Phase I will prove feasibility in a breadboard system developed to demonstrate the ability to guide an ablation catheter to the location of an electrical source within a phantom torso. This work will serve as the foundation for development and in-vivo test of a full prototype guidance system in Phase II.