1. Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, USA
2. Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Mayo Clinic, Rochester, MN, USA
3. Cardiology Department, Health Research Institute of the Balearic Islands (IdISBa), Hospital Universitari Son Espases, Palma, Spain
4. Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
5. Facultad de Medicina, Universitat de les Illes Balears (UIB), Palma de Mallorca, Balearic Islands, Spain
6. Medical Statistics Department, London School of Hygiene & Tropical Medicine, London, UK