1. Department of Signal Theory and Communications, Telematics, and Computing, Universidad Rey Juan Carlos, Fuenlabrada, Madrid, Spain
2. Cardiac Bioelectricity and Arrhythmia Center, Washington University in St. Louis, St. Louis, MO, USA
3. Arrhythmia Unit, Hospital Clínico Universitario Virgen de la Arrixaca, El Palmar, Murcia, Spain