1. From the Division of Cardiology, Department of Medicine, University of Western Ontario, London, ON, Canada (J.A.W., G.W.); and Imaging Laboratories, Robarts Research Institute (J.A.W., M.R.), Lawson Health Research Institute (J.A.W., J.B., R.T.T., F.S.P.), and Department of Medical Biophysics (R.T.T., R.S.P., G.W.), Western University, London, ON, Canada.