Session P71.1

Effects of Anaesthesia on Atrial Fibrillation Organization during Catheter Ablation Procedures

R Cervigón*, J Moreno, C Heneghan, J Mateo, C Sánchez

Universidad de Castilla-La Mancha
Cuenca, Spain

Radio-frequency ablation is a powerful therapeutic strategy for the restoration of sinus rhythm in patients suffering from atrial fibrillation (AF). However, the effect of anaesthetic agents on atrial electrophysiological properties during the procedure has not been previously fully investigated. . In this paper, we analyze intra-atrial recordings and extract physiological information which discriminates between the states “before” (baseline) and “during” anaesthetic infusion (propofol) in 27 patients with AF. These features were extracted using time-domain and frequency-domain analysis methods, as well as using some approaches from complex system theory and chaos theory (sample entropy). The frequency domain measurements showed that the average AF cycle length, an index of atrial refractoriness, is increased as an effect of anaesthesia (171.9±24.96 vs. 174.7 ± 22.66 ms. p=0.121), implying that atrial activation might be altered. In concordance, the organization index measurement measured during propofol infusion is slightly more organized than at baseline state (0.56±0.12 vs. 0.59±0.11, p=0.062). Using time-domain analysis, the cross-correlation function was calculated at the closest inter-electrode distance; as a result, it is possible to remark that during the anaesthetic infusion the correlation is greater in the right atrium (RA), with the opposite effect observed in the left atrium (LA), (ANOVA coupled with the Student-Newman-Keuls test, LA (0.507±0.075 (basal) vs. 0.491± 0.083 (propofol) and RA 0.511± 0.065 (basal) vs. 0.527±0.060 (propofol) p= 0.008). The same effects may be corroborated using the coherence sensitivity at the closest inter-electrode distance: (LA 0.282±0.114 (basal) vs. 0.260±0.090 (propofol) and RA 0.232±0.077 (basal) vs. 0.251±0.075 (propofol), p=0.008) and also with the SampEn of the time series (LA 0.077±0.002 (basal) vs. 0.080±0.001 (propofol) and RA 0.066±0.003 (basal) vs. 0.063±0.003 (propofol) p=0.023). A more pronounced difference at basal and propofol states is shown in paroxysmal AF subjects (LA 0.084±0.003 (basal) vs. 0.088± 0.007 (propofol) and RA (0.071±0.005 (basal) vs. 0.065±0.005 (propofol), p=0.007). The proposed methodology may provide additional insights to the understanding of the anti-arrhythmic role of the anaesthetic, by suggesting increased parasympathetic activation at atrial level, specifically during paroxysmal AF. In addition, the multiple site recordings allow the examination of the complexity of the arrhythmia over space, showing differences between LA and RA that may be helpful in the ablation procedure.

(Abstract Control Number: 104)