1. From the Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, MD (N.A.G., A.B., C.A.J., B.M., C.T., C.S.O., D.P.J., S.D.R., H.C., R.J.T.); Division of Cardiology, University Medical Center Utrecht, The Netherlands (A.S.J.t.R.); and Division of Cardiology, Department of Medicine, University at Buffalo, State University of New York (A.S.).