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Updated: Jul 10, 2026
08:10
Estimating Bilateral Atrial Function by Cardiovascular Magnetic Resonance Feature Tracking in Patients with Paroxysmal Atrial Fibrillation
Published on: July 20, 2022
Atrial fibrillatory cycle length: computer simulation and potential clinical importance
Michel Haissaguerre1, Kang-Teng Lim, Vincent Jacquemet
1Hôpital Cardiologique du Haut-Lévêque and University of Bordeaux II, Bordeaux, France. jacques.clementy@pu.u-bordeaux2.fr
Summary
Atrial fibrillatory cycle length (AFCL) predicts atrial fibrillation (AF) duration and ablation success. Shorter AFCL indicates more complex AF requiring extensive ablation for termination.
Area of Science:
- Cardiac Electrophysiology
- Computational Biology
- Medical Device Technology
Background:
- Atrial fibrillatory cycle length (AFCL) is a recognized surrogate for local atrial refractoriness.
- Understanding AFCL's clinical utility is crucial for optimizing catheter ablation strategies.
Purpose of the Study:
- To evaluate the clinical potential of AFCL as a predictor in atrial fibrillation (AF).
- To correlate AFCL with AF characteristics and catheter ablation outcomes using computational modeling and human subject data.
Main Methods:
- Biophysical computer modeling of AF with multiple focal sources to assess AFCL dynamics.
- Analysis of electrophysiological data from 178 patients undergoing AF catheter ablation.
- Automated monitoring of AFCL in atrial appendages and correlation with procedure complexity and success.
Main Results:
- Computer simulations revealed an inverse relationship between the number of AF-maintaining sources and AFCL.
- Clinical data showed shorter AFCL correlated with longer AF duration and more extensive ablation required for termination.
- A critical AFCL of approximately 200 ms was identified for AF conversion, with AFCL prolonging exponentially during ablation stages.
Conclusions:
- AFCL is inversely associated with the number of AF-maintaining sources, as demonstrated by computational modeling.
- AFCL serves as a significant predictor of AF duration, type, and the ease of successful catheter ablation therapy.
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