Creating Order From Chaos

Abstract

> It’s always seemed like a big mystery how nature, seemingly so effortlessly, manages to produce so much that seems to us so complex. Well, I think we found its secret. It’s just sampling what’s out there in the computational universe. > > –Stephen Wolfram, 2010 Pathogenesis of nearly all arrhythmia relies on a fundamental premise—that there exists within the cellular milieu regions of unexpected or unwanted heterogeneous conduction that may allow for initiation and propagation of wave fronts along a nonstandard pattern. The simplest paradigm for this may be atrioventricular reentrant tachycardias wherein 2 paths exist, both capable of propagating signals in either the antegrade or retrograde direction, but with fundamentally different conductive properties that ultimately allow for development of reentry with an appropriately timed stimulus. This appropriately timed stimulus, or trigger, has for the past 3 decades been the focus of electrophysiologists in the treatment of more complex arrhythmias that exist outside the ability of our modern day understanding and technology to map and ablate. Where a single circuit exists, mapping and ablation is straightforward, and we must prove it exists and that it participates in the tachycardia, identify its location, and then determine the best means by which to ablate it. However, in the case of atrial fibrillation, understanding, identifying, and determining an ideal ablative solution for the substrate is eminently more difficult. This is because the propagation and continuation of atrial fibrillation is fundamentally dependent on the continuous activity of many sites simultaneously. Thus, we have often referred to atrial fibrillation almost as chaos, throwing up arms at the seemingly inexplicable and indescribable complexity and focused instead on the elimination of triggers, whether by pulmonary vein isolation or targeting other sites, rather than the myocardial substrate responsible for arrhythmia maintenance as we would with any other simpler arrhythmia, such …