1. Cardiac Pacing Unit, Cardiology Department, University Hospital of Geneva , Rue Gabrielle Perret Gentil 4, 1211 Geneva 14 , Switzerland
2. First Department of Cardiology and Electrocardiology and Arterial Hypertension, Jagiellonian University , Kopernika 17, 31-501 Kraków , Poland
3. Hospital Universitario y Politecnico La Fe , Avinguda de Fernando Abril Martorell 106, 46026 Valencia , Spain
4. Centro de Investigaciones Biomédicas en RED en Enfermedades Cardiovasculares (CIBERCV) , Av. Monforte de Lemos, 3-5 Pabellón 11, Planta 0 28029 Madrid , Spain
5. Cardiocenter, Third Faculty of Medicine, Charles University and University Hospital, Kralovske Vinohrady , Ruská 87, 100 00 Prague 10 , Czech Republic
6. Heart Centre, University Hospital Ghent , Corneel Heymanslaan 10, 9000 Gent , Belgium
7. The First Affiliated Hospital of Wenzhou Medical University , Nanbaixiang, Wenzhou 325000 , China
8. Bethel-Clinic , Burgsteig 13, 33617, Bielefeld , Germany
9. Department of Medicine, McGill University Health Center , 1001 Decarie Boulevard, H4A 3J1 Montreal (Quebec) , Canada
10. Brigham and Women's Hospital , 75 Francis St, Boston, MA 02115 , USA
11. Department of Cardiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Center , Universiteitssingel 50, 6229 Maastricht , the Netherlands
12. Geisinger Wyoming Valley Medical Center , 1000 East Mountain Blvd., Wilkes-Barre, PA 18711 , USA
13. National Heart and Lung Institute, Imperial College London , Guy Scadding Building, Dovehouse St, London SW3 6LY , UK
14. Arrhythmia and Electrophysiology Unit, Santa Maria della Misericordia General Hospital , Viale Tre Martiri 140, 45100 Rovigo , Italy