1. From the Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O.); Gilead Sciences, Inc, Foster City, CA (J.L.H., R.F.-F., C.B., L.B.); Department of Preclinical and Clinical Pharmacology and Center of Molecular Medicine, University of Florence, Florence, Italy (R.C.); Veterans Affairs Palo Alto Health Care System and Stanford University, Palo Alto, CA (J.M.); and Hypertrophic Cardiomyopathy Center, Division of Cardiology, Tufts Medical Center, Boston, MA (M.S.M.).