Cardiac Arrhythmia Service, Cardiology Division, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.
J Cardiovasc Transl Res. 2012 Apr;5(2):196-212. doi: 10.1007/s12265-012-9352-0. Epub 2012 Feb 24.
A decade of research has established the role of cardiac resynchronization therapy (CRT) in medically refractory, moderate to severe systolic heart failure (HF) with intraventricular conduction delay. CRT is an electrical therapy instituted to reestablish ventricular synchronization in order to improve cardiac function and favorably modulate the neurohormonal system. CRT confers a mortality benefit, improved HF hospitalizations, and functional outcome in this population, but not all patients consistently demonstrate a positive CRT response. The nonresponder rate varies from 20% to 40%, depending on the defined response criteria. Efforts to improve response to CRT have focused on a number of fronts. Methods to optimize the correction of electrical and mechanical dyssynchrony, which is the primary target of CRT, has been the focus of research, in addition to improving patient selection and optimizing post-implant care. However, a major issue in dealing with improving nonresponse rates has been finding an accurate and generally accepted definition of "response" itself. The availability of a standard consensus definition of CRT response would enable the estimation of nonresponder burden accurately and permit the development of strategies to improve CRT response. In this review, we define various aspects of "response" to CRT and outline variability in the definition criteria and the problems with its inconsistencies. We describe clinical, laboratory, and pacing predictors that influence CRT response and outcome and how to optimize response.
经过十年的研究，心脏再同步治疗（CRT）在药物难治性、中度至重度收缩性心力衰竭（HF）伴室内传导延迟中的作用已经确立。CRT 是一种电治疗方法，旨在重建心室同步，以改善心功能并有利地调节神经激素系统。CRT 为该人群提供了死亡率益处、改善 HF 住院和功能结局，但并非所有患者都始终表现出积极的 CRT 反应。根据定义的反应标准，无反应者的比率在 20%至 40%之间变化。改善 CRT 反应的努力集中在多个方面。除了改善患者选择和优化植入后护理外，还致力于优化电和机械不同步的纠正方法，这是 CRT 的主要目标，这也是研究的重点。然而，在提高无反应率方面的一个主要问题是找到“反应”本身的准确且普遍接受的定义。CRT 反应的标准共识定义的可用性将能够准确估计无反应者的负担，并允许制定改善 CRT 反应的策略。在这篇综述中，我们定义了 CRT 反应的各个方面，并概述了定义标准的可变性及其不一致性的问题。我们描述了影响 CRT 反应和结局的临床、实验室和起搏预测因素，以及如何优化反应。
