1. From the Division of Cardiology (K.E.W., M.L.A., L.L.M., L.L.D.), Department of Medicine and Department of Physiology, University of California, Los Angeles School of Medicine; Molecular Disease Branch (J.M.H.), National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Md; and Division of Cardiology (T.D., R.D.), Harbor-University of California, Los Angeles Medical Center.