Cycle Length Estimation Using Accurate Adaptive Detection of Local Activations in Atrial Intracardiac Electrograms

Abstract

The normal electrical potential propagates throughout the atria periodically. During atrial arrhythmias its prop-agation is modified because the substrate is not homoge-neous and new sources of punctual electrical activity appear. The periodic behavior of activation remains predom-inant, but becomes local in different parts of the atria. It is characterized by cycle length (CL) which measures the frequency of activation and can be computed from intrac-ardiac bipolar electrograms (EGM) recorded by a mapping catheter during the catheter ablation procedure. The CL value of different mapped zones is an extremely important resource for physicians when performing persis-tent Atrial Fibrillation (AF) ablation because it helps to identify pathological zones and define the ablation strat-egy. Thus, a reliable estimation of the CL of atrial tissue is essential. The complexity of this task stems from the large variability in EGM morphology influenced by mul-tiple wavefronts, fragmentation and added noise. In this work, we propose a cycle length estimator that can process the complex mapping signals recorded during atrial arrhythmias ablation and reliably provide the frequency of their periodic activity.