Role of substrate and triggers in the genesis of cardiac alternans, from the myocyte to the whole heart: implications for therapy.
Role of substrate and triggers in the genesis of cardiac alternans, from the myocyte to the whole heart: implications for therapy.
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DOI：
10.1161/circulationaha.111.033563
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发表时间：
2012-01-24
期刊：
影响因子：
37.8
通讯作者：
Armoundas AA
中科院分区：
文献类型：
--
作者：
Merchant FM;Armoundas AA
1908年，赫林首先描述了心电交替现象，这是一种在心电波形中的搏动振荡现象。1对交替现象的兴趣主要集中在心脏动作电位(AP)复极阶段的交替，也称为复极交替(RA)。更具体地说，RA与恶性室性心律失常和心源性猝死(SCD)的风险增加有关，涉及范围广泛的病理生理条件，包括缺血性和非缺血性充血性心力衰竭伴左室射血分数受损和最近的心肌梗死。结构正常的心脏在变时性刺激4、5或显著代谢应激条件下也可产生2，3心脏交替。6鉴于已经发表了几篇关于RA的机制和微伏T波交替(MTVA)测试的临床风险分层方面的综合综述论文7-10，在本报告中，我们试图提出一个新的框架，说明“适当的”底物和“适当的”触发事件如何协同作用于从细胞到全心水平产生心脏交替的机制，并提出使用RA指导治疗的新方面。
Electrocardiographic alternans, a phenomenon of beat-to-beat oscillation in electrocardiographic (ECG) waveforms, was first described by Hering in 1908. 1 Much of the interest in the alternans phenomenon has focused on alternans during the repolarization phase of the cardiac action potential (AP), also known as repolarization alternans (RA). More specifically, RA has been associated with an increased risk for malignant ventricular arrhythmias and sudden cardiac death (SCD) across a wide range of pathophysiological conditions, including both ischemic and nonischemic congestive heart failure with impaired left ventricular (LV) ejection fraction and recent myocardial infarction. 2, 3 Cardiac alternans can also be produced in structurally normal hearts under conditions of chronotropic stimulation4, 5 or significant metabolic stress. 6Given that several comprehensive review papers7–10 have been published on the mechanisms of RA and the clinical risk-stratification aspects of microvolt T-wave alternans (MTWA) testing, in the present report we have attempted to present a novel framework for how an “appropriate” substrate and an “appropriate” trigger event may synergistically contribute to the mechanisms that generate cardiac alternans from the cellular to the whole-heart level, and we propose novel aspects of the use of RA to guide therapy.