Spectral Analysis Identifies Sites of High-Frequency Activity Maintaining Atrial Fibrillation in Humans

Mapping of Rotors in Atrial Fibrillation: From Animal Models to Humans

“…Mapping and analysis of the spatio-temporal organization of wave propagation during fibrillation can provide important clues about its underlying mechanisms. Mapping data recently published by our group support the hypothesis that acute AF in the structurally normal sheep heart [4][5][6][7][8][9] and in some patients [10] is not a totally random phenomenon.…”

“…An additional adenosine infusion performed while measuring activity at a secondary HDF site also showed an increase in DF, but to a lesser extent. Interestingly, in this patient the arrhythmia terminated during post-mapping ablation at the primary HDF site, supporting again the critical role of such sites as AF drivers [10]. Compared to baseline, adenosine significantly accelerated the primary and secondary HDF sites in these patients from about 5.0 to 6.7 Hz [25], demonstrating that the sites involved in the maintenance of AF are clearly affected by adenosine.…”

“…Some clinical studies have been able to demonstrate rotor activity in humans; however, in general a direct visualization of rotors in patients is more challenging than in animals. We therefore have focused our analysis in humans on the distribution of DFs during AF to gain mechanistic and therapeutic insight [10,25,55,56]. Using electro-anatomic mapping and Fourier spectral methods we generated three-dimensional, whole-atrial DF maps on which HDF sites were ablated and resulted in significant slowing of the arrhythmia and termination of sustained AF in 87% of patients with paroxysmal AF [10].…”

“…We determined the effects of adenosine infusion on DF at varying locations of both atria with the idea that adenosineinduced acceleration reveals reentry as the mechanism of AF maintenance and rules out an automatic or triggered mechanism. We generated baseline DF maps of the LA using novel real-time spectral analysis software that allowed determination of the specific high DF (HDF) sites likely to harbor the AF drivers [10] in paroxysmal AF patients. Then the adenosine effect was measured at the primary and secondary HDF sites in the LA.…”

“…To characterize the activation patterns on the surface of the atria we have used a combination of high-resolution video imaging techniques and bipolar electrograms recordings [23]. The chapter focuses on describing the electrical activation of the atria in space and time and makes extensive use of spectral and phase analyses to provide a solid and impartial quantification of the complex patterns of propagation as observed during AF in both animals [5,24] and patients [10,25]. …”