1. Specialization School of Cardiology, University of Siena, Viale Mario Bracci 16, 53100 Siena, Italy
2. Cardiovascular Diseases Unit, Le Scotte Hospital, University of Siena, Viale Mario Bracci 16, 53100 Siena, Italy
3. National Institute for Cardiovascular Research, Via Irnerio 48, 40126 Bologna, Italy
4. Department of Clinical, Internal, Anesthesiology and Cardiovascular Sciences, Sapienza University of Rome, Viale del Policlinico, 155, 00161 Rome, Italy