[1] Osped S Maria Annunziena, Unita Epidemiol, Azienda Sanit Firenze, Florence, Italy
[2] Azienda Osped Univ Careggi, Dipartimento Cuore & Vasi, Florence, Italy
[3] Cooperat Leonardo, Florence, Italy
[4] European Hosp, Dept Cardiovasc Sci, Div Cardiol, Rome, Italy
[5] Azienda Osped Univ Careggi, Dipartimento Diagnost Lab, Florence, Italy
[6] Northwestern Univ, Sch Med, Cardiol Clin Serv, Chicago, IL USA
[7] Vet Affairs Med Ctr, Div Cardiol, San Diego, CA 92161 USA
[8] Vet Affairs Med Ctr, Dept Med, San Diego, CA 92161 USA
[9] Univ Calif San Diego, San Diego, CA 92103 USA