1. From the Division of Cardiology (D.S.O., J.S.L., T.S., Y.M., Z.W., I.-K.J.) and Biostatistics Center (H.L.), Massachusetts General Hospital, Harvard Medical School, Boston; Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan (T.H., H.Y., T.Y, K.O.); and Division of Cardiology, Kyung Hee University, Seoul, South Korea (I.-K.J.).