Defibrillation of Ischemic Ventricular Fibrillation

缺血性心室颤动的除颤

基本信息

批准号：
6727538
负责人：
GREGORY P WALCOTT
金额：
$ 21.53万
依托单位：
UNIVERSITY OF ALABAMA AT BIRMINGHAM
依托单位国家：
美国
项目类别：
财政年份：
2001
资助国家：
美国
起止时间：
2001-05-01 至 2006-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/6727538
关键词：
electric countershock heart resuscitation heart electrical activity myocardial ischemia /hypoxia nonhuman therapy evaluation swine ventricular fibrillation

项目摘要

DESCRIPTION (the applicant's description verbatim): Sudden Cardiac Death is a major cause of mortality in the United States. In an effort to attack this problem, the concept of a Chain of Survival has been presented as a way to characterize the tasks necessary for a successful resuscitation. Early defibrillation is central to improved survival rates following out of hospital cardiac arrest. Very little is known about defibrillation efficacy of spontaneous arrhythmias in the presence of acute ischemia. A much larger shock is needed to halt ventricular fibrillation that occurs spontaneously in the presence of acute ischemia than to halt electrically induced ventricular fibrillation in the non-ischemic heart. We will study the activation patterns following successful and failed defibrillation shocks with the heart in four conditions designed to model different aspects of ischemic ventricular fibrillation: (1) acute regional ischemia causing spontaneous ventricular fibrillation, (2) acute regional ischemia followed by electrically induced ventricular fibrillation, (3) acute regional ischemia causing spontaneous ventricular fibrillation which in turn causes prolonged global ischemia, and (4) acute regional ischemia causing spontaneous ventricular fibrillation in the setting of an old myocardial infarction. We will test the hypothesis that, in the setting of an ischemically induced spontaneous arrhythmia, a defibrillation shock must do three things: (1) stop all fibrillation wavefronts, (2) not restart fibrillation, and (3) stop the trigger of the original arrhythmia. We will also test the hypothesis that a major determinant of whether or not a spontaneous arrhythmia caused by acute ischemia can be easily defibrillated depends upon the mechanism of initiation of the arrhythmia and duration of the arrhythmia. To test these hypotheses, we will use electrical mapping techniques to map the initiation of ventricular arrhythmias, and then map the first few post-shock activations following delivery of a defibrillation shock. By developing an understanding of how a defibrillation shock succeed or fails under these conditions, we will be in a better position to develop new defibrillation techniques that will hopefully increase survival rates of patients suffering an episode of sudden cardiac death.

描述（申请人的描述逐字描述）：突然心脏死亡是一个美国死亡率的主要原因。为了攻击这一点问题，已经提出了生存链的概念表征成功复苏所需的任务。早期的除颤是改善医院后生存率的核心心脏停搏。关于除颤功效知之甚少在存在急性缺血的情况下自发性心律不齐。更大的冲击需要停止自发发生在急性缺血的存在比停止电引起的心室非缺血性心脏的纤颤。我们将研究激活模式成功并在四人中对心脏的除颤冲击失败。旨在模拟缺血性心室不同方面的条件纤颤：（1）急性区域缺血，引起自发性室纤颤，（2）急性区域缺血，然后是电诱导的心室纤颤，（3）急性局部缺血，引起自发的心室纤颤，反过（4）在旧心肌梗塞的设置。我们将检验以下假设。不变诱导的自发性心律不齐的设置，一种除颤冲击必须做三件事：（1）停止所有颤音波前，（2）不重新启动纤颤，（3）停止原始心律不齐的扳机。我们还将检验以下假设急性缺血引起的自发性心律不齐很容易被除颤取决于心律不齐的起始机制和持续时间心律不齐。为了检验这些假设，我们将使用电气映射技术绘制心室心律不齐的启动，然后绘制前几个发射后激活进行除颤冲击后激活。经过对除颤冲击如何成功或失败有了了解在这些条件下，我们将有更好的位置发展新的除颤技术，这些技术有望提高生存率患者患有心脏突然死亡的发作。