Why the study?
Alternating organised and disorganised periods during AF are routinely observed, but their mechanistic significance remains unclear.
Do the temporal dynamics of organised AF events exhibit power-law distributions indicative of self-organised criticality, and how do they differ between paroxysmal and persistent AF or with flecainide?
Do the temporal dynamics of organised AF events exhibit power-law distributions indicative of self-organised criticality, and how do they differ between paroxysmal and persistent AF or with flecainide?
Answers are grounded in this paper and cite their sources.
Atrial fibrillation dynamics operate near a critical state consistent with self-organised criticality, with differences between paroxysmal and persistent AF that can be modulated by flecainide.
Background Alternating organised and disorganised periods during atrial fibrillation (AF) are a phenomenon routinely observed in the electrophysiology lab, yet their mechanistic significance remains unclear. We hypothesised that the temporal distribution of organised and disorganised events differs between paroxysmal AF (PAF) and persistent AF (PsAF) and that power-law conformance of these distributions may serve as a marker of self-organised criticality (SOC). Purpose To investigate whether the temporal dynamics of organised AF events exhibit power-law distributions indicative of SOC, and to assess phenotype-specific differences between PAF and PsAF. Methods In a prospective multicentre study, one-minute pre-ablation AF recordings (16-pole HD-grid) from patients undergoing catheter ablation for AF were analysed at predefined atrial sites. Signal analysis was repeated following intravenous flecainide infusion in a subset of patients to quantify its impact on power-law signatures and electrogram characteristics. Organisation was quantified by phase transformation and mean phase coherence. Episodes of AF organisation were defined as more than two seconds of organised electrograms on a stable multi-polar catheter. Electrophysiological properties (Dominant Frequency, Shannon Entropy, and AFCL) were compared between organised and disorganised domains. Power-law conformance, indicative of SOC, was evaluated using the Akaike Information Criterion (AIC). Results Across 7,111 organised episodes from 117 patients (54 PAF, 63 PsAF), organised event durations exhibited power-law distributions in both PAF (α=1.07; ΔAIC=44.1) and PsAF (α=1.11; ΔAIC=11.1). Tail analysis (>50th percentile) revealed persistence of power-law only in PAF (ΔAIC=40.5). Periods of disorganisation were characterised by higher dominant frequency (DF: 5.33±1.05 vs 5.02±1.03Hz, P<0.001), greater Shannon entropy (ShEn: 2.82±0.26 vs 2.37±0.35, P<0.001), and shorter AF cycle length (AFCL: 200±44 vs 211±51ms, P<0.001). Flecainide prolonged AFCL, reduced DF and ShEn, and strengthened power-law fit for organised events. Conclusion AF dynamics operate near a critical state consistent with SOC. Differences in tail properties between PAF, PsAF, and under flecainide may explain spontaneous termination and identify therapeutic targets. Modulating criticality could represent a powerful new mechanism to restore rhythm stability.
No takes yet. Share an insight, caveat, or question.
Tonchev et al. (2026) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: