1. Multidisciplinary Cardiovascular Research Centre and Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, U.K.
2. Division of Cardiovascular and Diabetes Research, Multidisciplinary Cardiovascular Research Centre, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, U.K.
3. Department of Medical Physics and Engineering, Leeds Teaching Hospitals NHS Trust, Leeds, U.K.
4. National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD