1. Cardiology Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, 55 Fruit St, Yawkey 5E, Boston, MA 02114-2750, USA
2. Cardiovascular Imaging Research Center, Departments of Medicine and Imaging, Massachusetts General Hospital, 165 Cambridge St., Boston, MA 02114, USA
3. BioMedical Engineering and Imaging Institute, Icahn School of Medicine at Mount Sinai, 1470 Madison Ave., New York, NY 10029, USA
4. Department of Cardiovascular Medicine, Case Western Reserve University, 10900 Euclid Ave., Cleveland, OH 44106, USA