1. Clinica Mediterranea; Napoli Italy
2. Heart Lung Centre; Leiden University Medical Centre; Leiden Netherlands
3. Department of Cardiology, Cardiovascular Institute, Hospital Clınic de Barcelona; University of Barcelona; Barcelona Spain
4. Department of Electrophysiology; Heart Center Leipzig; Leipzig Germany
5. Department of Cardiology; Institute for Clinical and Experimental Medicine; Prague Czech Republic
6. Arrhythmia Department and Electrophysiology Laboratory; State Research Institute of Circulation Pathology; Novosibirsk Russia
7. ANMCO Research Centre; Florence Italy
8. EURObservational Research Programme; European Society of Cardiology; Sophia-Antipolis France
9. Division of Cardiology, Department of Medical Sciences, Citta della Salute e della Scienza; University of Turin; Turin Italy
10. Arrhythmia Center; Sheba Medical Center, Ramat Gan, and Sackler Faculty of Medicine, Tel Aviv University; Tel Aviv Israel
11. Department of Invasive Cardiac Electrophysiology; Acibadem City Clinic Tokuda Hospital; Sofia Bulgaria
12. Department of Cardiology, Institution of Medical Science; Uppsala University; Uppsala Sweden