Atrial fibrillation driver identification through regional mutual information networks: a modeling perspective

Abstract

Purpose: Effective identification of electrical drivers within remodeled tissue is a key for improving ablation treatment for atrial fibrillation. We have developed a mutual information, graph-based approach to identify and propose fault tolerance metric of local efficiency as a distinguishing feature of rotational activation and remodeled atrial tissue.

Methods: Voltage data were extracted from atrial tissue simulations (2D Karma, 3D physiological, and the Multiscale Cardiac Simulation Framework (MSCSF)) using multi-spline open and parallel regional mapping catheter geometries. Graphs were generated based on varied mutual information thresholds between electrode pairs and the local efficiency for each graph was calculated.

Results: High-resolution mapping catheter geometries can distinguish between rotational and irregular activation patterns using the derivative of local efficiency as a function of increasing mutual information threshold. The derivative is decreased for rotational activation patterns comparing to irregular activations in both a simplified 2D model (0.0017 ± 1 × 10^-4 vs. 0.0032 ± 1 × 10^-4, p < 0.01) and a more realistic 3D model (0.00092 ± 5 × 10^-5 vs. 0.0014 ± 4 × 10^-5, p < 0.01). Average local efficiency derivative can also distinguish between degrees of remodeling. Simulations using the MSCSF model, with 10 vs. 90% remodeling, display distinct derivatives in the grid design parallel spline catheter configuration (0.0015 ± 5 × 10^-5 vs. 0.0019 ± 6 × 10^-5, p < 0.01) and the flower shaped open spline configuration (0.0011 ± 5 × 10^-5 vs. 0.0016 ± 4 × 10^-5, p < 0.01).

Conclusion: A decreased derivative of local efficiency characterizes rotational activation and varies with atrial remodeling. This suggests a distinct communication pattern in cardiac rotational activation detectable via high-resolution regional mapping and could enable identification of electrical drivers for targeted ablation.

Keywords: Atrial fibrillation; Cardiac mapping; Electrical drivers; Local efficiency; Mutual information; Rotational activation.