Blind analysis of atrial fibrillation electrograms: A sparsity-aware formulation

The problem of blind sparse analysis of electrogram (EGM) signals under atrial fibrillation (AF) conditions is considered in this paper. A mathematical model for the observed signals that takes into account the multiple foci typically appearing inside the heart during AF is firstly introduced. Then,...

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Detalles Bibliográficos
Autores: Luengo García, David, Monzón García, Sandra, Trigano, Tom, Vía Rodríguez, Javier, Artés Rodríguez, Antonio
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universidad de Cantabria (UC)
Repositorio:UCrea Repositorio Abierto de la Universidad de Cantabria
Idioma:inglés
OAI Identifier:oai:repositorio.unican.es:10902/9924
Acceso en línea:http://hdl.handle.net/10902/9924
Access Level:acceso abierto
Palabra clave:Biomedical signal processing
Atrial fibrillation electrograms
Sparsity-aware learning
LASSO regularization
Spectral analysis
Descripción
Sumario:The problem of blind sparse analysis of electrogram (EGM) signals under atrial fibrillation (AF) conditions is considered in this paper. A mathematical model for the observed signals that takes into account the multiple foci typically appearing inside the heart during AF is firstly introduced. Then, a reconstruction model based on a fixed dictionary is developed and several alternatives for choosing the dictionary are discussed. In order to obtain a sparse solution, which takes into account the biological restrictions of the problem at the same time, the paper proposes using a Least Absolute Shrinkage and Selection Operator (LASSO) regularization followed by a post-processing stage that removes low amplitude coefficients violating the refractory period characteristic of cardiac cells. Finally, spectral analysis is performed on the clean activation sequence obtained from the sparse learning stage in order to estimate the number of latent foci and their frequencies. Simulations on synthetic signals and applications on real data are provided to validate the proposed approach.