Background: This study aims to evaluate the impact of catheter ablation for atrial fibrillation (AF) on left atrial (LA) flow dynamics and geometrical changes.
Methods: This exploratory study included computational flow simulations from 10 patients who underwent catheter ablation for AF. Complete cardiac cycle dataset was simulated before and after ablation using computational fluid dynamics. The study main endpoints were the changes in LA volume, LA velocity, LA wall shear stress (WSS), circulation (Γ), vorticity, pulmonary vein (PV) ostia area, and LA vortices before and after ablation.
Results: There was an average decrease in LA volume (11.58 ± 15.17%) and PV ostia area (16.6 ± 21.41%) after ablation. A non-uniform trend of velocity and WSS changes were observed after ablation. Compared with pre-ablation, 4 patients exhibited lower velocities, WSS distributions, and a decreased Γ (> 8.5%), while 6 developed higher velocities and WSS distributions. These geometrical changes dictated different flow mixing in the LA and distinct vortex patterns, characterized by different spinning velocities, vorticities, and rotational directions. Regions with q-criterion > 0 were found to be dominant in the LA, indicating prevalent rotational vortex structures.
Conclusion: Catheter ablation for AF induced different geometrical changes on the LA and the PVs, therefore influencing flow mixing and vortex patterns in the LA, in addition to overall velocity and WSS distribution. Further exploration of the impact of catheter ablation on intracardiac flow dynamics is warranted to discern patterns that may correlate with clinical outcomes.
Keywords: Atrial fibrillation; Catheter ablation; Hemodynamics; Left atrium.
© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.