A single-center trial of electrographic flow mapping and concomitant voltage mapping in sinus rhythm and atrial fibrillation (FLOW EVAL-AF)

Background: Electrographic flow (EGF) mapping reconstructs atrial electrical wavefront propagation, potentially revealing sources of atrial fibrillation (AF). Electrographic flow consistency (EGFC) measures the concurrence of wavefront patterns and may provide insights into atrial substrate health. This study aimed to compare EGF patterns during atrial fibrillation (AF) with sinus rhythm (SR) and explore the correlation between EGFC and regional bipolar voltage.

Methods: In this single-center, prospective study, AF patients underwent mapping of the atria using bipolar voltage and EGF mapping. Mapping was performed during both AF and SR using a 16-electrode grid catheter (bipolar mapping) and a 64-pole basket catheter (EGF mapping). EGFC was computed as the average modulus of individual EGF vectors, reflecting flow pattern consistency.

Results: Ten patients were enrolled. EGF identified 11 sources with a mean source activity of 32 ± 9% during AF. Eight out of eleven sources in AF converted to passive "sinks" when mapped in SR. EGFC was significantly lower during AF compared to SR (0.74 ± 0.14 vs 1.0 ± 0.11 AUs, P < 0.01), consistent with EGFC quantifying the more chaotic wavefront propagation during arrhythmia. No spatial correlation between areas of high EGFC during AF and SR was observed. EGFC correlated with bipolar voltage across rhythms and atria (r = 0.647, P < 0.0001).

Conclusion: EGF patterns varied by rhythm with AF showing lower EGFC values. EGFC correlated with bipolar voltage across rhythms and atria, suggesting its potential as an atrial myopathy marker akin to high-density voltage mapping and offering insights into atrial substrate health. Trial registration ClinicalTrials.gov Identifier: NCT06260670.