1. From the Division of Heart Rhythm Services, Department of Cardiovascular Diseases (A.S., P.A.N., V.K., B.Q., Z.I.A., P.B., S.J.A., P.A.F., M.J.A.), Division of Pediatric Cardiology, Department of Pediatric and Adolescent Medicine (R.K.R., J.M.B., S.J.A., M.J.A.), and Department of Molecular Pharmacology and Experimental Therapeutics (J.M.B., M.J.A.), Windland Smith Rice Sudden Death Genomics Laboratory, and Division of Biomedical Statistics and Informatics (C.G.S.), Mayo Clinic, Rochester, MN; Czech...