Defibrillation of Ischemic Ventricular Fibrillation

缺血性心室颤动的除颤

• 批准号: 6333860
• 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
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-05-01 至 2005-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6333860
• 关键词: electric countershock heart resuscitation; heart electrical activity; myocardial ischemia /hypoxia; nonhuman therapy evaluation; swine; ventricular fibrillation

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（申请人的逐字描述）：心源性猝死是一种 是美国死亡的主要原因。为了努力攻击这个 问题中，生存链的概念被提出作为一种解决问题的方法。 描述成功复苏所需的任务。早期的 除颤对于提高出院后的生存率至关重要 心脏停搏。人们对除颤的功效知之甚少 急性缺血时出现自发性心律失常。更大的震动 需要阻止自发发生的心室颤动 存在急性缺血而不是停止电诱导心室 非缺血性心脏中的颤动。我们将研究激活模式 成功和失败的除颤电击后心脏有四次 旨在模拟缺血性心室不同方面的条件 颤动：（1）急性局部缺血引起自发性心室颤动 颤动，(2) 急性局部缺血，随后发生电诱发 室颤，（3）急性局部缺血引起自发性 心室颤动进而导致长时间的全身缺血，以及 (4)急性局部缺血引起自发性心室颤动 陈旧性心肌梗塞的情况。我们将检验以下假设： 缺血引起的自发性心律失常、除颤 电击必须做三件事：（1）停止所有颤动波前，（2）不 重新启动颤动，并且（3）停止原始心律失常的触发。我们 还将检验以下假设：是否存在一个主要决定因素 急性缺血引起的自发性心律失常很容易除颤 取决于心律失常的起始机制和持续时间 心律失常。为了测试这些假设，我们将使用电气绘图技术 绘制室性心律失常的起始图，然后绘制前几个 除颤电击后的电击后激活。经过 了解除颤电击如何成功或失败 在这种条件下，我们将能够更好地开发新的 除颤技术有望提高患者的生存率 患有心源性猝死的患者。