Abstract 13235: Reentrant Sources in Persistent AF Are Located in Regions with Specific Spatial Patterns of Fibrosis
Introduction: Fibrosis is associated with increased risk of persistent atrial fibrillation (psAF), but it remains unknown how the specific distribution of fibrosis determines the preferential locations of atrial reentrant sources (RSs).
Hypothesis: We hypothesized that RSs in psAF patients persist in fibrotic regions with distinct spatial characteristics that can be quantitatively assessed.
Methods: Late Gadolinium Enhancement LGE-MRI and noninvasive electrocardiographic imaging (ECGI) data were acquired from patients with psAF. Patient specific, biophysically accurate atrial models were developed from images (Fig A). A dynamic pacing protocol was used to induce psAF in models. Locations of persistent RSs in simulations (reentries lasting >2s) were compared to ECGI data to validate each model. Then, at each point in the model atria, we computed local spatial metrics for the volume within a 2.5 mm radius: fibrosis density (proportion of LGE tissue by volume), fibrosis clustering (diffuse or patchy) by Moran’s I, and complexity of fibrosis pattern by Shannon entropy.
Results: In all patient-specific models, persistent RS locations were the same as those detected by ECGI (within 2 cm of each other, as in Fig B). At such locations, fibrosis characteristics were distinct from those in the rest of the atria (p 0.6, clustering > 0.8, and complexity > 0.8 occupied only 3.25% of atrial volume (Fig D), suggesting that a limited amount of tissue had the specific fibrosis pattern that favored RS persistence.
Conclusion: Persistent RSs in psAF are harbored by fibrotic regions with distinct spatial characteristics. Identifying such regions can help determine the optimal targets for ablation of psAF.
Author Disclosures: S. Zahid: None. P.M. Boyle: None. P. Malamas: None. F. Vadakkumpadan: None. R. Dubois: Ownership Interest; Modest; CardioInsight. Consultant/Advisory Board; Modest; CardioInsight. E.J. Vigmond: Ownership Interest; Modest; CardioSolv, LLC. M. Haissaguerre: Other Research Support; Modest; CardioInsight. Ownership Interest; Modest; CardioInsight. M. Hocini: Other Research Support; Modest; CardioInsight. Ownership Interest; Modest; CardioInsight. P. Jais: Other Research Support; Modest; CardioInsight. Ownership Interest; Modest; CardioInsight. H. Cochet: None. N.A. Trayanova: Ownership Interest; Modest; CardioSolv, LLC.
- © 2014 by American Heart Association, Inc.