Estimation of the correlation length of activation processes during atrial fibrillation

Atrial tissue wavelength critically determines susceptibility to atrial fibrillation (AF), but this measurement is not obtainable in humans. The authors speculated that wavelength also determines the extent of spatial organization during AF and developed a quantitative measure of this organization (the spatial correlation length, L_c ) by determining the distance over which activation sequences measured at equally spaced sites within the human atria are well-correlated during AF. L_c varied among patients, was highly reproducible within single patients, and changed predictably with administration of anti-arrhythmic drugs (AAD). Quantitative assessment of the extent of spatial organization of activation sequences during AF may allow for estimation of electrophysiologic changes underlying the susceptibility to AF, and may provide an objective measure of AAD action in vivo