1. From the Clinical Pharmacology Unit (C.M.M., S.W., I.S.M., Y., I.B.W.), University of Cambridge, Addenbrooke’s Hospital, Cambridge, United Kingdom; Department of Medicine (D.E.N.), University of Edinburgh, Edinburgh Royal Infirmary, Edinburgh, United Kingdom; and the Department of Cardiology (B.M., J.R.C.), Wales Heart Research Institute, Cardiff, United Kingdom.