1. From the Division of Cardiology (H.A., T.S., J.D., M.M.Z., R.E., V.C., R.H.H., S.N., R.D.B., H.C., M.R.A., E.M., A.C.L., H.R.H.), Johns Hopkins University School of Medicine, Baltimore, Md; Laboratory of Cardiac Energetics (H.A., B.H., E.R.M.), National Heart, Lung, and Blood Institute, NIH, Bethesda, Md; Division of Cardiology (T.D.), University of Maryland, Baltimore; and Heart and Vascular Research Center (J.K.D.), MetroHealth Hospital, Case Western Reserve University, Cleveland, Ohio.