1. Department of Cardiac Surgery, Hospital Germans Trias i Pujol, Badalona, Spain
2. Department of Cardiac Surgery, Complejo Hospitalario Universitario A Coruña, CHUAC, A Coruña, Spain
3. Department of Cardiac Surgery, Hospital Infanta Cristina - Badajoz, Badajoz, Spain
4. Department of Cardiac Surgery, Hospital Universitario Vall d’Hebron, Barcelona, Spain
5. Department of Cardiac Surgery, Hospital Universitari Bellvitge, Hospitalet de Llobregat, Spain
6. Department of Cardiac Surgery, Hospital Universitario Virgen de la Arraixaca, Murcia, Spain
7. Department of Cardiac Surgery, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
8. Department of Cardiac Surgery, Hospital Universitario Gregorio Marañon, Madrid, Spain
9. Department of Cardiac Surgery, Hospital Universitario La Princesa, Madrid, Spain
10. Department of Cardiac Surgery, Hospital Universitario Dr. Negrin, Las Palmas, Spain
11. Department of Cardiac Surgery, Hospital Universitario Puerta de Hierro, Madrid, Spain
12. Department of Cardiac Surgery, Hospital Universitario Virgen de la Salud – Toledo, Toledo, Spain
13. Department of Cardiac Surgery, Hospital Universitario Marques de Valdecilla (HUMV), Santander, Spain