1. Heart Failure Unit and Cardiology Department , Hospital Universitari Germans Trias i Pujol , Badalona , Spain
2. CIBERCV, Instituto de Salud Carlos III , Madrid , Spain
3. Heart Failure and Cardiac Regeneration (ICREC) Research Program, Health Sciences Research Institute Germans Trias i Pujol (IGTP) , Badalona , Barcelona , Spain
4. Biochemistry Service, University Hospital Germans Trias i Pujol , Badalona , Spain
5. Department of Cardiovascular Medicine , Mayo Clinic , Rochester , MN , USA
6. Cardiology Division , Massachusetts General Hospital Harvard Medical School, Harvard University , Boston , MA , USA
7. Department of Medicine , Universitat Autònoma de Barcelona , Barcelona , Spain
8. Heart Institute , Hospital Universitari Germans Trias i Pujol, Carretera de Canyet s/n , 08916 Badalona , Barcelona , Spain