1. From the Department of Cardiology (M.H., J.A.C.L., I.M.K., K.F., D.S., H.A., J.R., J.E.M., H.C., S.N.), Department of Radiology (S.L.Z.), The Johns Hopkins University School of Medicine, Baltimore, MD; and Department of Biostatistics (V.Z.), Department of Epidemiology (S.N.), The Johns Hopkins Bloomberg School of Public Health, Baltimore, MD.