Basic/Translational Science -> Computer Modeling/Simulation D-AB02 - Machine Learning and Computational Modeling: A Step Towards Precision Medicine? (ID 16) Abstract Plus

D-AB02-05 - Fibrosis Explains AF Recurrences After Catheter Ablations. A Simulation Study (ID 1403)

 A. Gharaviri: Nothing relevant to disclose.


Background: AF recurrences in more than 20% of patients after PVI, despite proven non PV reconnections, is suggesting that non-PV foci may play an important role in AF initiation in this subset of patients. It was shown clinically that the extent of fibrosis (FIB) in a patient is well correlated with the PVI outcome.
Objective: We hypothesised that an increase in FIB level leads to an increase in AF recurrence likelihood after PVI and PVI plus linear ablations (PVI+).
Methods: The effect of FIB on AF initiation likelihood after PVI and PVI+ was simulated in a highly detailed 3D model of the human atria with realistic electrophysiology and fibre orientations. The model geometry was based on MR images and histo-anatomical studies. Both catheter ablation (CAB) strategies, radiofrequency and cryoablation, were simulated. AF was initiated in each simulation by a train of stimuli applied to 20 different locations, outside of ablated area, in both atria.
Results: In simulations without PVI, an increase in FIB level led to a significant increase in AF initiation likelihood. In simulations with 0% and 50% FIB, PVI (created by either strategies) and PVI+ caused a significant reduction in AF initiation likelihood. In simulations with 70% FIB, all CAB patterns failed to reduce AF initiation likelihood significantly.
Conclusion: A computer model in which fibrosis degree was increased showed an increase in AF initiation prior to CABs and an increase in AF initiation rate after CABs. These results suggest that in addition to isolation of PV ectopic foci, PVI reduces AF initiation and maintenance by reducing atrial mass in moderately remodelled atria, but fails to do so in severely remodelled atria.