From the Department of Medicine, Vanderbilt University, Nashville, TN (M.B.S., J.M., T.E., Z.Y., J.D., S.K.G., P.S., A.K., S.P.W., D.M.R., C.R.E., D.D.); Department of Electrophysiology, Heart Center Leipzig, Leipzig, Germany (A.B., L.U., A.A., P.S., G.H., D.H.); Cardiac Arrhythmia Service and Cardiovascular Research Center, Massachusetts General Hospital, Boston (S.A.L., H.S., P.T.E.); and Department of Medicine, University Hospital Munich, Munich, Germany (M.F.S.). (At 2015-04)