1. From the Division of Cardiovascular Medicine (Z.P., H.-Y.C., M.P., S.S., A.J.M., R.C., S.S.), The Gill Heart Institute, University of Kentucky, Lexington; the School of Medicine (J.S.L.), The University of North Carolina at Chapel Hill; and the Department of Biostatistics (R.C.), College of Public Health, University of Kentucky, Lexington and the Department of Veterans Affairs Medical Center, Lexington, KY (S.S.S.).