MEMS Sensors for Arrhythmia Detection and Interventions

描述（由申请人提供）：尽管几十年的深入研究，继发于心室颤动（VF）的猝死仍然是美国和其他发达国家死亡的主要原因。最近，关于VF的机制提出了几个有希望的假设。然而，目前还不可能利用现有的实验技术来确定哪种（或哪种）理论最适用于VF。为了解决这一问题，我们建议：1)构建一个能够以高时空分辨率和最小组织损伤评估心脏激活和复极化的纳米元件心脏测绘系统；2)采用一种新颖的相位映射技术对映射数据进行分析，目的是识别窦性心律、室性心动过速和室性心动过速期间的相位奇点的位置和数量；3)利用相位奇异性数据来区分三种可能的VF机制-具有纤颤传导的锚定转子，弯曲转子或多转子。MEMs技术将用于构建具有集成电极的微型机械针状结构，该结构可通过超声波激活，以最大限度地减少插入过程中的组织损伤。该电极阵列将用于绘制固定起搏和VF期间体外犬心室心肌、正常和急性缺血猪心脏的激活和复极图。映射数据将使用快速傅立叶解调技术进行分析，以识别VF期间的奇异点和波矢量。二维和三维心肌的计算机模型也将用于生成替代数据集，以测试分析算法。这项研究的结果将导致三个关键领域的重大进展：以前所未有的空间分辨率绘制心脏电活动的设备的开发；应用更新和更复杂的技术来分析大型地图数据集；在关于室性心动过速和纤颤发生的新假设的背景下解释高分辨率制图数据。综上所述，这些数据采集、分析和解释方面的进展有望带来新的、更有效的方法来识别和治疗有致死性室性心动过速风险的患者。

DESCRIPTION (provided by applicant): Despite decades of intensive investigation, sudden death secondary to ventricular fibrillation (VF) remains a leading cause of mortality in the US and other developed countries. Recently, several promising hypotheses regarding the mechanism for VF have been introduced. However, it has not been possible using currently available experimental techniques to determine which theory (or theories) is most applicable to VF. To address this issue, we propose to: 1) construct a cardiac mapping system from nanofabricated components that is capable of assessing cardiac activation and repolarization with high spatial and temporal resolution and with minimal tissue damage; 2) use a novel phase mapping technique to analyze the mapping data, with the objective of identifying the location and number of phase singularities during sinus rhythm, ventricular tachycardia and VF; 3) use the phase singularity data to distinguish between three putative mechanisms for VF - an anchored rotor with fibrillatory conduction, a meandering rotor or multiple rotors. MEMs technology will be used to construct microscale mechanical needle-like structures with integrated electrodes that are ultrasonically activated, to minimize tissue damage during insertion. The electrode arrays will be used to map activation and repolarization in canine ventricular myocardium in vitro and in normal and acutely ischemic pig hearts in situ during fixed pacing and during VF. The mapping data will be analyzed using a fast Fourier-demodulation technique to identify singularities and wave vectors during VF. Computer models of 2- and 3-D myocardium also will be used to generate surrogate data sets for testing the analysis algorithms. The results of this study will lead to significant advances in three key areas: development of devices to map cardiac electrical activity with unprecedented spatial resolution; application of newer and more sophisticated techniques to analyze large mapping data sets; interpretation of high resolution mapping data within the context of novel hypotheses regarding the genesis of ventricular tachycardia and fibrillation. Taken together, these advances in data acquisition, analysis and interpretation are expected to lead to new and more effective means of identifying and treating patients at risk for the development of lethal ventricular tachyarrhythmias.