1. Cardiocentro Ticino Institute, Ente Ospedaliero Cantonale, Lugano, Switzerland
2. Cardiac Intensive Care Unit, Arrhythmia and Electrophysiology and Experimental Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
3. Department of Cardiology, Ospedale San Giovanni, Via Ospedale 12, 6500 Bellinzona, Switzerland
4. Service of Clinical Epidemiology & Biometry, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
5. Department of Molecular Medicine, Section of Cardiology, University of Pavia, Pavia, Italy