[1] Sacred Heart Catholic Univ, Dept Cardiovasc & Pulm Sci, Rome, Italy
[2] Isola Tiberina Gemelli Isola, Operat Unit Diagnost Intervent Cardiol, Rome, Italy
[3] Fdn Policlin Univ A Gemelli IRCCS, Dept Cardiovasc Med, Rome, Italy
[4] Univ Siena, Univ Hosp Le Scotte, Dept Med Sci Surg & Neurosci, Div Internal Med,Electroimmunol Unit, Siena, Italy
[5] Virginia Commonwealth Univ, Pauley Heart Ctr, Richmond, VA USA
[6] Univ Virginia, Robert M Berne Cardiovasc Res Ctr, Charlottesville, VA USA
[7] Univ Virginia, Div Cardiol, Charlottesville, VA USA
[8] Virginia Commonwealth Univ, Dept Kinesiol & Hlth Sci, Richmond, VA USA
[9] Virginia Commonwealth Univ, Div Pulm & Crit Care, Richmond, VA USA