1. From the Hypertrophic Cardiomyopathy Center, Division of Cardiology, Tufts Medical Center, Boston, Mass (M.S.M., J.J.F., J.E.U.); Department of Medicine, Pediatrics, and Molecular Pharmacology, Experimental Therapeutics/Divisions of Cardiovascular Diseases and Pediatric Cardiology, and the Mayo Clinic Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minn (J.M.B., M.J.A.); Departments of Medicine (Cardiovascular Division) (T.H.H., W.J.M.) and Radiology (W.J.M.), Beth...