1. Department of Internal Medicine, University and Hospital of Fribourg, Chemin des Pensionnats 2-6, 1708 Fribourg, Switzerland
2. Department of Cardiology, University and Hospital of Fribourg, Chemin des Pensionnats 2-6, 1708 Fribourg, Switzerland
3. Department of Cardiology, University and Hospital of Geneva, Rue Gabriel-Perret-Gentil 4, 1205 Geneva, Switzerland