Mechanistically-based mapping of @entity1 XXXX .

@entity1 @entity74 @entity955 @entity299
UNASSIGNED: The mechanisms underpinning @entity1 @entity299 remain elusive. In his 1913 treatise on 'Dynamic Equilibrium in the Heart', Mines proposed that an activation wave front could propagate repeatedly in a circle, initiated by a stimulus in the vulnerable period. While the dynamics of activation and recovery are central to @entity299 , these physiological data are rarely used in clinical mapping. Fibrillation is a rapid irregular rhythm with @entity74 resulting from 2 fundamental mechanisms - sources in preferred cardiac regions or spatially diffuse self-sustaining activity, i.e. with no preferred source. On close inspection, however, this debate may also reflect mapping technique. Fibrillation is initiated from triggers by regional dispersion in repolarization, slow conduction and wavebreak, then sustained by non-uniform interactions of these mechanisms. Notably, optical mapping of action potentials in @entity955 ( @entity955 ) show spiral wave sources (rotors) in nearly all studies including @entity1 , while most traditional electrogram analyses of @entity955 do not. Techniques may diverge in fibrillation because electrograms summate non-coherent waves within an undefined field whereas optical maps define waves with a visually defined field. Also fibrillation operates at the limits of activation and recovery, that are well represented by action potentials while fibrillatory electrograms poorly represent repolarization. We conclude by suggesting areas for study that may be used, until such time as optical mapping is clinically feasible, to improve mechanistic understanding and therapy of @entity1 @entity299 . This article is protected by copyright. All rights reserved.
