Lalani Gautam G, Trikha Rishi, Krummen David E, Narayan Sanjiv M
University of California Medical Center, Veterans Affairs San Diego.
Circ J. 2014;78(10):2357-66. doi: 10.1253/circj.cj-14-0478. Epub 2014 Sep 10.
Outcomes for patients with atrial fibrillation (AF) have changed little despite many advances in technology. In large part, this reflects fundamental uncertainty about the mechanisms for AF in humans, which must reconcile diverse observations. Despite the complexity of AF, many electrophysiologists have witnessed modulation of 'chaotic' AF after the first few ablation lesions, or before lines are complete or trigger sites are isolated, and numerous analyses demonstrate temporospatial stability in AF. These common observations challenge the concept that AF is driven by spatially disorganized, widespread mechanisms. Using mathematical techniques applied to other complex systems, evidence is rapidly accumulating that human AF is largely sustained by localized rotors and focal sources. Elimination of sources by Focal Impulse and Rotor Modulation (FIRM)-guided ablation has been shown by independent laboratories to substantially improve success compared with pulmonary vein isolation alone. These data advance our mechanistic understanding of AF. Randomized trials are underway to verify the relative efficacy of ablation at AF sources (substrate) vs. conventional trigger ablation. The renewed focus on AF substrates is a paradigm shift, but also a re-alignment of concepts for AF towards those for other cardiac arrhythmias that are generally defined by sustaining mechanisms (substrates).
尽管技术取得了诸多进展，但心房颤动（AF）患者的治疗结果变化不大。这在很大程度上反映了人类房颤机制存在根本的不确定性，而这必须协调各种不同的观察结果。尽管房颤情况复杂，但许多电生理学家都见证了在最初几次消融损伤后，或在消融线完成之前或触发点隔离之前，“混乱”房颤的调制，并且大量分析表明房颤存在时空稳定性。这些常见观察结果对房颤由空间上无序、广泛机制驱动这一概念提出了挑战。运用应用于其他复杂系统的数学技术，越来越多的证据表明人类房颤在很大程度上由局部转子和局灶性起源维持。独立实验室已表明，与单纯肺静脉隔离相比，通过局灶性冲动和转子调制（FIRM）引导的消融消除起源可显著提高成功率。这些数据推进了我们对房颤机制的理解。正在进行随机试验以验证房颤起源（基质）消融与传统触发点消融的相对疗效。对房颤基质的重新关注是一种范式转变，也是房颤概念朝着那些通常由维持机制（基质）定义的其他心律失常概念的重新调整。
