1. Unit of Electrophysiology, Belcolle Hospital, 01100 Viterbo, Italy
2. Cardiology Department, University of Rome Sapienza, 00100 Rome, Italy
3. Cardiology Unit, University Hospital of Northamptonshire, Northampton NN1 5BD, UK
4. Department of Medical-Surgical Sciences and Biotechnologies, Sapienza University of Rome, 04100 Latina, Italy
5. Mediterranea Cardiocentro, 80133 Naples, Italy
6. Unit of Cardiology and Electrophysiology, San Carlo di Nancy Hospital, 00100 Rome, Italy
7. Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy
8. Department of Medicine, Di Lorenzo Clinic, 67052 Avezzano, Italy
9. Department of Medical Biotechnologies, Division of Cardiology, University of Siena, 53100 Siena, Italy