1. Department of Cardiac Surgery; Central Universitary Hospital of Asturias; Oviedo Spain
2. Department of Cardiology; Central Universitary Hospital of Asturias; Oviedo Spain
3. Department of Cardiac Surgery, College of Medicine; University of Arizona; Tucson Arizona
4. Department of Cardiology; Hospital of Cabueñes; Gijón Spain
5. Department of Cardiology; Hospital San Agustín; Avilés Spain