X-RAY BACKSCATTER IMAGING OF VENTRICULAR ACTIVATION

缺血性心脏病和心肌病是主要的心脏疾病 在美国，导致成年人猝死的疾病。 死亡通常是室性心动过速变性所致 变成了纤颤。外科和经导管消融治疗 都是从这种心律失常的治疗中出现的。这些 治疗需要脑室的激活标测来定位 在手术切除或消融前出现异常的电通路。 术中标测是目前选择的方法 找到这样的小路。术中标测程序， 然而，它们是复杂、耗时和侵入性的。有，因为 因此，有相当大的动机将其程度降至最低 必然性。一种可定位的非侵入性测绘技术 手术前异常的电信号通路 相当大的价值。这项提议的目的是发展 这种基于后向散射x-的检测的技术 射线。背向散射X射线将被用来产生高精度 自由壁的位移、速度和加速度图 心脏。然后将使用这些高时间分辨率地图 以确定电异位活动的位置。后向散射 标测过程是非侵入性的，既不需要切割，也不需要 注射，并使用最低水平的辐射。 该提案的具体目标是：a)制定必要的 用于高精度墙体动力学测量的硬件和软件 使用辐射后向散射测量技术，以及b) 使用该硬件和软件进行中的激活映射研究 一种室性心律失常的起搏犬模型。的最终目标 该方案是一种无创的高精度激活标测 适用于在人体上启动测试的技术。

Ischemic heart disease and cardiomyopathy are major cardiac disorders leading to sudden death in adults in the United States. Death usually results from ventricular tachycardia degenerating into fibrillation. Surgical and trans-catheter ablation therapies have emerged from the treatment of such arrhythmias. These treatments require activation mapping of the ventricles to locate aberrant electrical pathways prior to surgical excision or ablation. Intraoperative mapping is currently the method of choice for locating such pathways. Intraoperative mapping procedures, however, are complex, time consuming, and invasive. There is, as a result, a considerable incentive to minimize their extent and necessity. A non-invasive mapping technique capable of locating aberrant electrical pathways prior to surgery, would be of considerable value. The purpose of this proposal is to develop such a technique based upon the detection of backscattered x- rays. Backscattered x-rays will be used to create high precision displacement, velocity and acceleration maps of the free walls of the heart. These high temporal resolution maps will then be used to locate site of electrical ectopic activity. The backscatter mapping procedure is non-invasive, requires neither cutdowns nor injections, and uses minimal levels of radiation. The specific aims of the proposal are: a) to develop the necessary hardware and software for measuring high precision wall dynamics using a radiation backscatter measurement technique, and b) to use that hardware and software for activation mapping studies in a paced canine model of ventricular arrhythmias. The end goal of this proposal is a non-invasive high precision activation mapping technique suitable for initiating testing in humans.