1 Division of Cardiology, Cardiocentro Ticino Institute, Ente Ospedaliero Cantonale (EOC), Via Tesserete 48, 6900 Lugano, Switzerland.
2 Unit of Cardiology, IRCCS Policlinico St. Orsola-Malpighi, Department of Experimental, Diagnostic and Specialty Medicine-DIMES, University of Bologna, 40138 Bologna, Italy.
3 Department of Cardiology, Division of Heart and Lungs, University Medical Center Utrecht, Utrecht University, 3584 CX Utrecht, The Netherlands.