1. Noninvasive Cardiac Imaging Laboratory, University of Chicago Medical Center , 5758 S. Maryland Ave., MC 9067, Chicago, IL 60637 , USA
2. Department of Cardiology, Northwestern Medicine Central DuPage Hospital , Winfield, IL , USA
3. Philips Healthcare , Cambridge, MA , USA
4. Health Research Institute, MedStar Health and Georgetown University , Washington, DC , USA