1. From the Division of Cardiology (R.B.P., J.N., V.R., M.C., K.P., H.S., J.J.G., L.I., A.H.K.), Feinberg School of Medicine, Northwestern University, Chicago, Ill; the Division of Cardiology (A.A.A.-A., T.N., M.S.L.), Tufts Medical Center, Tufts University School of Medicine, Boston, Mass; and the Institute of Cardiac Sciences (A.A.A.-A.), Sheikh Khalifa Medical City, Abu Dhabi, United Arab Emirates.