Recent Insights into the Mechanisms Underlying Persistent Atrial Fibrillation

innovationsincrm.com: 8/1/12

Atrial fibrillation (AF) is a gradually progressive atrial disease process manifesting as the most common heart rhythm disorder. Early in its clinical course, the arrhythmia may be frequently triggered by rapid firing of impulses from focal sources. Almost all cases of true paroxysmal AF are caused by ectopic signals that originate in the thoracic veins, especially the pulmonary veins, allowing catheter-mediated elimination of sources, with clinical success rates of 70–85%.¹By contrast, atrial tissue that has widespread electrostructural alterations resulting from oxidative stress, inflammation, and atrial fibrosis is largely the source of persistent forms of AF wherein the clinical outcome of drug therapy and/or ablation is variably low.

In addition to focal sources, widely spread, biatrial substrate plays a large role in initiating and sustaining persistent AF. The improvement in the outcomes of therapy for persistent AF needs better understanding of the underlying complex mechanisms. Below, we present recently developed insights into the mechanisms of persistent AF from invasive and non-invasive mapping techniques. read more