1. From the Department of Cardiology, Guy’s and St. Thomas’s Hospital, London, United Kingdom (N.C., C.A.R., J.B., M.C., M.O., M.W., R.R., J.G.); Department of Cardiovascular Imaging, Division of Imaging Sciences and Biomedical Engineering, King’s College, London, United Kingdom (N.C., M.B., R.R.); Department of Mechanical Engineering, University College London, London, United Kingdom (B.H., D.W.); and Neurocardiology Unit, University College London Hospitals, London, United Kingdom (P.T.).