1. Arrhythmia Section, Cardiovascular Clinic Institute, Hospital Clínic, University of Barcelona, 170 Villarroel Street, Barcelona, Catalonia, Spain
2. Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
3. Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Catalonia, Spain